United States      Solid Waste and    Pesticides and   EPA530-R-92-010
            Environmental Protection  Emergency Response  Toxic Substances  PB92-162 551
            Agency        (OS-305)      (TS-799)     April 1992
£EPA      Preliminary Use and
            Substitutes Analysis of
            Lead and Cadmium in
            Products in Municipal
            Solid Waste
                                       Printed on Recycled Paper

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 PRELIMINARY USE AND SUBSTITUTES
 ANALYSIS FOR LEAD AND CADMIUM IN
PRODUCTS IN MUNICIPAL SOLID WASTE
                  Prepared by:

           Economics and Technology Division
          Office of Pollution Prevention and Toxics
           U.S. Environmental Protection Agency

                  Prepared for:

                Office of Solid Waste
           U.S. Environmental Protection Agency
                 January 27, 1992

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               CERTIFICATION
ICF Incorporated certifies that the ink used to
print this document is completely free of lead
and/or cadmium.  The Xerox* toner and developer
products used to produce this report do not
intentionally contain lead and/or cadmium nor do
they contain these elements as impurities or
byproducts.
                  - ii -

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                              TABLE OF CONTENTS
 SUMMARY REPORT 	   x

  I.   INTRODUCTION  	   1

      A.  Limitations	'.-	3
      B.  References   	4

 II.   PLASTICS   	   5

      A.  Overview of  Plastics  Industry  	   6
      B.  Additives Used  in  the Processing  of  Plastics   	7
      C.  Consumption  of  Lead-  and  Cadmium-containing Products  in
         Plastics  	20
      D.  Potential Substitutes for Lead- and  Cadmium-containing
         Additives for Plastics   	  27
      E.  References   	44

III.   PIGMENTS	46

      A.  Overview of  the Pigment Industry   	46
      B.  Uses  of  Lead- and  Cadmium-containing Pigments    	  46
      C.  Consumption  of  Lead and Cadmium in Pigments    	46
      D.  Potential Substitutes of  Lead- and Cadmium-containing
         Pigments  	46
      E.  References   	53

 IV.   SOLDER	54

      A.  Overview of  the Soldering Industry   	54
      B.  Solder Use Areas	  55
      C.  Consumption  of  Lead and Cadmium in Solder    	61
      D.  Potential Substitutes for Lead- and  Cadmium-containing
         Solders    	65
      E.  References   	78

  V.   LEAD-ACID BATTERIES   	  81

      Reference	    82

 VI.   NICKEL-CADMIUM  BATTERIES   	  83

      A.  Overview of  the Battery Industry   	83
      B.  Use of Nickel-cadmium Batteries	84
      C.  Consumption  of  Cadmium in Nickel-cadmium Batteries   	  85
      D.  Potential Substitutes for Nickel-cadmium Batteries   	  87
      E.  Limitations  on  Substitution    	  91
      F.  References   	94
                                    - iii  -

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                               TABLE OF CONTENTS
                                   (Continued)

                                                                           Page

 VII.  GLASS AND CERAMIC PRODUCTS  	 95

       A.   Overview of Glass/Ceramic Products   	 95
       B.   Uses  of Lead and Cadmium in  Glass/Ceramic  Products   ....... 95
       C.   Consumption of Lead and Cadmium in  Glass/Ceramic  Products   .  .   103
       D.   Potential Substitutes  for Lead  and  Cadmium in
           Glass/Ceramic Products  	   106
       E.   References  	   113

VIII.  BRASS AND BRONZE PRODUCTS	115

       A.   Overview of Copper  Alloys Industry   	   115
       B.   Consumption of Lead in Brass and Bronze    	116
       C.   Potential Substitutes  for Lead  in Brass  and Bronze   	117
       D.   References  	122

  IX.  CADMIUM-PLATED PRODUCTS 	   123

       A.   Overview of the Plating Industry  	123
       B.   Consumption of Cadmium in Electroplating  	   125
       C.   Potential Substitutes  for Cadmium in Metallic Coatings   ....   125
       D.   References  	131

   X.  COLLAPSIBLE TUBES  	   T32

       A.   Overview of Tube Industry	132
       B.   Use of Lead Tubes   	132
       C.   Consumption of Lead in Tubes  	132
       D.   Potential Substitutes  for Lead  Tubes   	132
       E.   References  	136

  XI.  OTHER PRODUCTS	137

       A.   Foil  Wine Wrappers   	137
       B.   Used  Oil   	137
       C.   Rubber (Elastomer)  Products    	   139
       D.   Printing Inks    	146
       E.   Electric Blankets and  Heating Pads   	150
       F.   References  	152
                                     - iv -

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                                LIST OF TABLES
                                                                          Page
Table SR-1. Discards of Lead and Cadmium by Use Area in MSW in
            1986	
                                                                xi
Table SR-2. Lead and Cadmium Pigments and Potential Substitutes 	  xiv

Table SR-3.
Lead- and Cadmium-based Heat Stabilizers and Potential
Substitutes 	 	
                                                                            xv
Table SR-4. Potential Substitute Solders and Processes for Lead-
            and Cadmium-Containing Solder for Consumer Electronic,
            Consumer Can, and Light Bulb Applications	xviii

Table SR-5. Potential Substitutes for Nickel Cadmium Batteries   	 xx

Table SR-6. Potential Substitutes for Lead and Cadmium in Glass
            and Ceramics	xxiii
Table SR-7. Potential Substitutes for Lead-based Brass and Bronze
            Products  	
                                                               XXV
Table SR-8. Potential Substitutes for Cadmium Plating  	  xxvii

Table SR-9.
Table  1.


Table  2.

Table  3.


Table  U.


Table  5.


Table  6.


Table  7.


Table  8.

Table  9.
Potential Substitutes for Miscellaneous Products
Containing Lead or Cadmium	xxx

Discards of Lead and Cadmium by Use Area in MSW in
1986	2

Representative Thermoplastic and Thermosetting Resins 	  6

Lead and Cadmium Inorganic Pigments and Their
Performance Properties   	 12
Representative Cadmium and Lead-based Heat Stabilizers
and Their Properties   	
Advantages/Disadvantages of Lead-based Heat
Stabilizers  	
15
17
 Current  and Declining uses of Lead-based Heat
 Stabilizers	18

 Advantages/Disadvantages of Cadmium-based Heat
 Stabilizers	21

 Uses  for Cadmium-based Heat Stabilizers	22

 Discards of Lead  in  Pigments for Plastic in MSW	23
                                     - v -

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                                LIST OF TABLES
                                  (Continued)
                                                                           Paee
Table 10.   Discards of Cadmium in Pigments for Plastic  in MSW	25

Table 11.   Discards of Lead in Stabilizers for PVC in MSW	26

Table 12.   Discards of Cadmium in Stabilizers for PVC in MSW	28

Table 13.   Potential Substitutes for Lead and Cadmium Pigments
            and Their Performance Properties  	  31

Table 14.   Costs:  Lead- and Cadmium-based Pigments and
            Potential Substitutes 	  32

Table 15.   Potential Substitutes for Lead-based Heat Stabilizers
            in Rigid PVC Products	35

Table 16.   Potential Substitutes for Lead-based Heat Stabilizers
            in Flexible PVC Products	38

Table 17.   Potential Substitutes for Cadmium-based Heat
            Stabilizers in Rigid PVC Products 	 40

Table 18.   Potential Substitutes for Cadmium^based Heat
            Stabilizers in Flexible PVC Products  	 41

Table 19.   Costs of Lead,  Cadmium,  and Potential Substitute Heat
            Stabilizers	42

Table 20.   Discards of Lead in Pigments for Plastic in MSW	47

Table 21.   Discards of Lead in Pigments for Rubber Products in
            MSW	48

Table 22.   Discards of Lead in Pigments for Ink and Miscellaneous
            Products in MSW	49

Table 23.   Discards of Cadmium in Pigments for  Plastic in MSW	50

Table 24.   Discards of Cadmium in Pigments for  Glass,  Ceramics,
            and Miscellaneous Products in MSW	51

Table 25.   Discards of Cadmium in Pigments for  Rubber  Products  in
            MSW	52

Table 26.   Discards of Lead in Solder in MSW	63

Table 27.   Advantages and Disadvantages of Potential Substitute
            Solders for Consumer Electronic Applications   	 67
                                    -  vi -

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                                LIST OF TABLES
                                  (Continued)
                                                                          Page
Table 28.   Advantages and Disadvantages of Substitute Processes
            and Solders for Consumer Can Applications  	 74

Table 29.   Advantages and Disadvantages of Potential  Substitute
            Solders for Light Bulb Applications	76

Table 30.   Discards of Cadmium in Nickel-cadmium Batteries in
            MSW	86

Table 31.   Advantages and Disadvantages of Substitute Batteries
            for Nickel-cadmium Batteries   	 93

Table 32.   Properties Lead Imparts to Glass/Ceramic Products 	 97

Table 33.   Discards of Lead in Glass and  Ceramics in  MSW	104

Table 34.   Discards of Cadmium in Pigments* for  Glass, Ceramics
            and Miscellaneous Products in  MSW	105

Table 35.   Potential Substitutes for Lead and Cadmium in Glass
            and Ceramics	107

Table 36.   Discards of Lead in Brass and  Bronze in MSW	118

Table 37.   Potential Substitutes for Lead-based Brass and Bronze
            Products	  120

Table 38.   Cost:  Lead-based Brass and Bronze Products  and Their
            Potential Substitutes 	  121

Table 39.   Discards of Cadmium in Plated  Parts  for Home
            Appliances and Electronics in  MSW	126

Table 40.   Characteristics of Potential Substitutes for Cadmium
            Plating	128

Table 41.   Costs  of Cadmium Plating and Potential Substitutes  	  129

Table 42.   Discards of Lead in Collapsible Tubes in MSW	133

Table 43.   Potential Substitutes for Collapsible Lead Tubes  	  134

Table 44.   Discards of Lead in Foil Wine  Wrappers in  MSW	138

Table 45.   Discards of Lead in Used Oil in MSW	140

Table 46.   Potential Substitutes for Alkyl lead Anti-knock Agents
            Used  as  Oil Lubricants	141

                                    - vii  -

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                                LIST OF TABLES
                                  (Continued)
Table 47.   Discards of Lead Pigments Used in Rubber Products in
            MSW	143

Table 48.   Discards of Cadmium in Pigments Used for Rubber
            Products in MSW	144

Table 49.   Potential Substitutes for Representative Lead- and
            Cadmium-based Vulcanizing Agents  	  146

Table 50.   Discards of Lead in Printing Inks in MSW	148

Table 51.   Advantages and Disadvantages of Potential Substitute
            Ink Pigments for Lead-containing Printing Ink
            Pigments	149

Table 52.   Discards of Cadmium in Electric- Blankets in MSW	151
                                   -  viii  -

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                               LIST OF FIGURES


                                                                          Paee

Figure 1.   Comparison of Through-Hole and Surface Mount
            Technologies  	

Figure 2.   Melting Temperature of Common Soldering Alloys  	  69
                                     - ix -

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                                SUMMARY REPORT




      The use of lead- and cadmium-containing articles that ultimately are




disposed of in municipal solid waste (MSW) facilities is the focus of a joint




project by the Office of Toxic Substances and the Office of Solid Waste.




Disposal of lead- and cadmium-containing products is a concern because




incineration of these items concentrates the metals in the ash residue which,




when landfilled, may lead to groundwater contamination.




      The Pollution Prevention Act of 1990, passed by Congress on October 27,




1990, asserts that, "pollution should be prevented or reduced at the source




wherever feasible (EPA 1990)."  This report identifies lead- and cadmium-




containing products that are disposed of in MSW, and provides information




regarding potential substitutes for these metals in various applications.  The




identification of technically feasible substitutes for lead and cadmium in




products found in MSW can be an important preliminary step towards pollution




prevention.




      In 1989, EPA issued a report entitled "Characterization of Products




Containing Lead and Cadmium- in Municipal Solid Waste in the United States,




1970 to 2000."  The current report examines technologically feasible lead and




cadmium substitutes for each of the products identified in the 1989 report.




To provide perspective on the sources of lead and cadmium in MSW, Table SR-1




provides estimates for 1986 discards of both metals in each product use area.




A full copy and/or the Summary Report of this document, "Preliminary Use and




Substitutes Analysis for Lead and Cadmium in Products in Municipal Solid




Waste," may be obtained by calling the EPA Resource Conservation and Recovery




Act  (RCRA) hotline number:  (800) 424-9346.
                                     -  x -

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  Table SR-1.  Discards of Lead and Cadmium by Use Area in MSW  in  1986
Product Area
Lead Acid Batteries
Plastics
Pigments3
Solder
Nickel/Cadmium Batteries
Glass and Ceramic Products
Brass and Bronze Products
Plated Products
Collapsible Tubes
Rubber Products
Other Products6
Lead Discards
(tons)
138,043
3,174
1,131
8,369
- 0
60,714
321
0
639
70
671
Cadmium Discards
( tons )
0
564
70
0
927
29
0
185
0
6
1
a Discards of pigments do not include pigments  consumed in plastics,
glass/ceramic products, or rubber products.   These discards are
covered in the sections on plastics,  glass/ceramic products,  and
rubber products.

b Other products  include used oil,  foil wine  wrappers,  electric
blankets and heating pads, and television and radio chassis.   279
tons of lead were discarded as part of television and radio chassis,
but future discards are expected to be zero  due to a change in
technology which has discontinued the use of lead in these products.

Sources:  EPA 1989, Franklin 1990.
                                 - xi -

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LIMITATIONS




      This report should be considered as a preliminary analysis due to the




limitations of its scope.  EPA has not performed primary research to identify




the substitutes for lead and cadmium described in this report.  Only




substances identified in published sources or by industry contacts and that




were known or considered to be potential substitutes have been included in




this analysis.  Because this report characterizes substitutes for both lead




and cadmium products, lead and cadmium are not considered as substitutes for




each other although this sometimes may be technically feasible.  Furthermore,




the substitution in this report  is based only on technical feasibility and




does not quantitatively assess economic factors that affect substitution or




the effect of potential substitutes on end products (e.g., different service




lives for substitute products).  While some information is provided on the




cost of potential substitute compounds, no economic analysis has been




performed to estimate the impacts of substituting for lead and/or cadmium




products.  This report, therefore, is not intended to draw conclusions about




the viability of actual substitution.  No economic analysis has been performed




to estimate the impacts of substituting for lead and/or cadmium products.




      In addition,  toxicities of substitutes are not discussed in this report




and  toxicity was not a criterion for identifying potential substitutes. Many




of the  classes  of chemicals  assessed have intrinsic toxicities that would be




of great concern  in other parts  of the manufacturing processes where there




would be human  or environmental  exposure to more bio-available forms of the




chemical or chemicals.   A more  focused, in-depth substitute characterization




 for  each chemical substitute in  each use area would be required to adequately




 assess  the hazard presented  by potential substitutes.
                                    - xii -

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LEAD AND CADMIUM SUBSTITUTES

       The range of consumer products that contain lead and/or cadmium and are

disposed of in MSW facilities is quite broad.  The remainder of this report

focuses on potential substitutes for lead-and cadmium-containing products in

each of the following areas:

                  plastics  (pigments and heat stabilizers);
                  pigments ;
                  solder;
                  lead-acid batteries;
                  nickel-cadmium batteries;
                  glass and ceramic products;
                  brass and bronze products;
                  cadmium-plated products;
                  collapsible tubes; and
                  other products (foil  wine  wrappers, used
                  oil,  rubber products,  and electric
                  blankets/heating pads).

      Plastics

      Lead- and cadmium-containing additives are used in plastics as both

pigments and heat stabilizers.   Table SR-2 lists lead and cadmium pigments and

their possible substitutes.   Table SR-3  lists lead-  and cadmium-based heat

stabilizers and their potential substitutes.

      For many of the lead-  and cadmium-based colorants,  potential substitutes

that provide similar hues have  been identified.   However,  for specific

applications hue may not be  the most important factor influencing the choice

of a pigment.   For example,  while some  organic pigments match the hue of

cadmium pigments, individual substitute  pigments may not be adequate in terms

of brilliance, lightfastness,  or high-temperature stability for  some

applications.   Furthermore,  the costs of these substitutes may be
       Pigments containing lead and/or  cadmium  are used  in paint, ink, paper,
rubber, glass,  and plastic products.   The discussion of  pigments  is  summarized
separately, but the majority of information on  pigments  is contained in  the
plastics section.

                                   -  xiii -

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                                          Table SR-2.  Lead and Cadmium Pigments and Potential Substitutes
Hue*
Lead and Cad*ium Pigments
                                   Potential Substitutes
                                                                                                   Performance
Yellow
 Lead chromate
 Cadmium sulfide
 CadmiuM sulfide and Zinc
                                                 Nickel titanium (NiTi)(inorganic)
                                                 Honoazo (organic)
                                                 Pyrazolone derivative (dye)
                                          General suitability, but greatly
                                          reduced tinting strength

                                          Suitable for low density polyethylene,
                                          and polystyrene. Not suitable for PVC.

                                          Suitable for polymethyl methacrylate,
                                          unplasticized PVC, and polystyrene.
Red
 Lead molybdate
 Cadmium/sulfide selenide
Iron oxide (inorganic)

Honoazo naphthol (organic)



Azo dye (dye)


Ouinacridone (organic)




Perylene (organic)
General suitability

Caution is needed in the case of high
density polyethylene articles
sensitive to distortion.

Suitable for polymethyl methacrylate,
unplasticized PVC, and polystyrene.

Suitable for polystyrene, PVC, low
density polyethylene. Caution' is needed
in high density polyethylene articles
sensitive to distortion.

Suitable for polystyrene, PVC, and low
density polyethylene.  Caution is needed
in high density polyethylene articles
sensitive to distortion.
* Potential substitutes are based on similar hue or color (i.e., any of the substitutes in a color group is assumed to be able to substitute for any
lead- or cadmium-based pigment with the same hue).  In  some cases  this may not be  the most important characteristic (e.g., heat stability may be an
important factor).

b For dyes, lightfastness and heat stability depend on  the plastic to be colored.

Sources:  Plastic Additives Handbook 1987.  Bayer Nobay  1989. and BASF 1989.
                                                                      -  xiv -

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                                    Table SR-3.  Lead- and Cadmium-based Heat Stabilizers and Potential Substitutes
      Stabilizer
Potential Substitutes
                                                                                                              Performance Comments
Lead Stabilizers
     Tribasic lead sulfate
     Dibasic lead phosphite
     Dibasic lead ph thaiate
     Dibasic lead stearate
     Normal lead stearate
     Dibasic lead carbonate
Organotin stabilizers




Barium/zinc stabilizers


letIone*
Suitable for a wide range of rigid and
flexible PVC applications although different
organotin stabilizers have different areas
of sui tabiIi ty.

Suitable for flexible PVC applications such
as shoes, sandals and soles.

Technically feasible substitute for cable
insulation and jacketing but not as a one-
for-one substitute for lead-based heat
stabilizers.
CadMiiM Stabilizers
     Bariu*ycadmiuM decanoate
      (and other fatty acid salts)
     BariuM/cadmiuM alkyl phenols
     Bari UN/cadmium benzoates
Zinc/calcium stabilizers
Organotin stabilizers
                                                    Barium/zinc stabilizers
Suitable for a wide range of flexible PVC
applications.

Suitable for a wide range of rigid and
flexible PVC applications although different
organotin stabilizers have different areas
of suitability.

Suitable for a wide range of rigid and
flexible PVC applications
     PVC = polyvinyl  chloride.

* Teflon* is a different class  of substitute  in  that  it would replace the end-product, PVC coatings, used for wire and cable insulation.

Sources:  Argus 1989a.  1969b,  1989c;  and Bedford 1989.
                                                                      -  xv  -

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significantly higher than their lead- and cadmium-containing counterparts.




Although the majority of companies no longer supply lead-based pigments,




cadmium pigments are still produced because their performance characteristics




are difficult to reproduce.




      Potential substitute products that can replace lead- and cadmium-




containing heat stabilizer products continue to be investigated due to the




toxicity of lead and cadmium compounds and the availability of an increasing




number of technically superior alternate products.  Lead and cadmium heat




stabilizers have seen widespread use because of their relatively low cost




compared to newer substitute products.




      The replacement of lead-based heat stabilizers in electrical cable




insulation and jacketing (power wiring,  telephone cable, and cords and




connectors for appliances and other consumer items)  has been difficult due ta




the critical properties of weathering, humidity resistance,  and thinness of




the jacket that lead imparts.  Potential substitutes for cadmium-containing




stabilizers have been identified.




      Pigments




      A pigment is defined as a substance that imparts  color to other




materials.   Pigments are normally insoluble in the material  in which they are




dispersed and usually are classified as  either organic  or inorganic.




      Pigments are used in a wide variety of products:   paint,  ink,  plastic,




paper, rubber, and glass.  The discussion of pigments  found  in the  Plastics




section above is applicable to lead- and cadmium-containing  pigment




substitution in general.




      Solder




      Solder is used in a variety of products to form both electrical  and




structural bonds between various types of materials.  The most  common  use of





                                    - xvi  -

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solder is to attach electrical components to printed circuit boards (Arconium




1989).  Tin/lead soldering alloy is the most common soldering alloy currently




in use (Kapp 1989).  The chief reason tin/lead solder is used to produce




consumer electronics is low cost (Talco 1989).   Products containing solder




that enter the municipal waste stream include consumer electronics, cans, and




light bulbs.




      Cadmium-containing solder is not used commonly to manufacture consumer




electronics.  Manufacturers avoid the use of cadmium because of health-related




concerns including the generation of poisonous  fumes during the soldering




operation (IPC 1989a, Keeler 1987, Indium 1989c).   Cadmium-containing solder




also is not used in the manufacture of cans,  but has been used in the past in




light bulb manufacturing (NFPA 1989, Sylvania 1989b).




      Four types of potential substitute solder alloys have been identified




for consumer electronics applications (see Table SR-4).   All of these solders




employ exotic metals making them much more expensive than tin/lead solder.




The characteristics of the potential substitute solder alloys differ from




tin/lead solder in terms of melting temperature, required flux type,  ability




to wet the surfaces to be soldered, and bond strength.




      Lead-acid Batteries




      Batteries are classified as primary and secondary cells.   Primary




battery cells are also known as "fuel cells"  because the active chemicals are




used in an irreversible reaction.  This type of cell typically is disposed of




after use.  By contrast, secondary battery cells may be recharged because




their chemistry is based on a highly reversible reaction.   After charging,




however, the materials do not return exactly to their previous (charged)




state, limiting the number of times the secondary battery can be reused.










                                   - xvii -

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         Table SR-4.  Potential Substitute Solders and Processes for  Lead-  and Cadmium-containing Solder  in Consumer  Electronic,  Consumer  Can,
                                                             and Light Bulb Applications
         Application Area
Potential Substitutes
            Performance Comments
         Consumer Electronics
Bismuth/tin solder
                                         Tin/silver solder
                                          Indium/tin solder
                                          Indium/silver solder
Suited to surface mount assembly technology.  Some bismuth alloys may
have unacceptably low melting temperatures for use in consumer
products.

Can be used to solder silver-plated base metal without significantly
solubilizing the silver.  Less ductile than indium and bismuth solder
alloys.  Higher cost than tin/lead solder.

Suited to surface mount assembly technology. Compatible with gold and
other precious metals.  Lou melting point not suitable for high
temperature applications.  As much as 20 times the cost of tin/lead
solder.

Suited to surface mount assembly technology.  Compatible with gold and
other precious metals.  Low melting point not suitable for high
temperature applications.  As much as 20 times the cost of tin/lead
solder.
         Consumer Can
         Light Bulb
Crimping process*

Welding process*

Tin solder


Indium-based solder
Eliminates the need for solder.

Eliminates the need for solder.

Eliminates the possibility of lead leaching into canned food products.
Nay be used in non-food cans.  More expensive than tin/lead solder.

More expensive than tin/lead solder.  Oxidizes when used in light bulb
manufacturing process. Tin/zinc solderOoes not flow as well as tin/lead
solder.
* Welding and crimping processes are  in a different class of substitutes in that they would replace the soldering process used for consumer cans.

Sources:  AOL 1990;  CHI 1989a,  1989b;  Indium 1989b. 1989c; IPC 1989b; Kapp 1989; Keeler 1987; Nanko 1979; NFPA 1989b; Sylvania 1989b, 1989c.
                                                                    -  xviii  -

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      Lead-acid batteries are currently the most commonly used type of




rechargeable battery.  These batteries are used for starting, ignition, and




lighting in virtually all motorized vehicles, and are used in other




applications where rechargeable portable power is desired (e.g.,  consumer




electronics such as power tools).   Lead-acid batteries continue to be widely




used because,  based on performance and cost of potential alternatives, no




acceptable substitutes currently exist.  Technologies that were examined for




this report include nickel-zinc, nickel-iron, and silver-zinc batteries




(nickel-cadmium batteries are not considered to be substitutes within the




scope of this analysis).




      Nickel-zinc batteries have a lower power density than lead-acid




batteries, a limited lifetime, relatively poor reliability,  and are two to




three times the cost of an equivalent sized lead-acid battery.  Nickel-iron




batteries also have a relatively low power density,  as well as poor low-




temperature performance and charge retention.  Silver-zinc batteries cost 20-




to 100 times as much as an equivalent sized lead-acid battery.  They also have




a limited lifetime and decreased performance at low temperatures  (Palmer




1988).




      Nickel-cadmium Batteries




      Nickel-cadmium (Ni-Cd) batteries are a type of secondary cell often used




in applications that consume large amounts of power (e.g., portable stereos




and photographic strobes).  Table SR-5 presents potential substitute batteries




that have been identified.  The potential substitutes examined are lithium,




silver-zinc, nickel-zinc, nickel-hydrogen, and primary (alkaline,  lithium,  and




carbon-zinc) batteries.  With the exception of primary batteries,  none of




these substitutes have been used much in consumer products because of




technical complications, reduced service life, and high cost.  In addition,
                                    -  xix  -

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       Table  SR-5.   Potential  Substitutes  for Nickel Cadmium Batteries
        Potential Substitute
        Performance Comments
Lithium Battery
Silver-Zinc Battery
Nickel-Zinc Battery
Nickel-Hydrogen Battery
Primary Battery
    (alkaline,  lithium,  and  carbon-
    zinc)
Less than half the lifetime of
nickel cadmium battery.  Sensitive
to abuse.

Less than one-fifth the lifetime of
nickel-cadmium battery.

Less than one-tenth the lifetime o-f
nickel-cadmium battery.

High atmospheric pressure required
in cell.

Not able to be recharged;  must be
replaced.
 Sources:  Yardney 1989a, 1989b; SAFT 1989a; Chemical Business 1989.
                                     - xx  -

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many of these technologies are currently  in an  embryonic  stage  of  development




and their costs are quite high.  As experimentation and development  proceeds,




the limitations and the costs of these substitute products may  be  reduced.




      One of the more promising technologies is the rechargeable lithium  cell




which is already used to a very limited extent  in some consumer applications.




According to one supplier, rechargeable lithium batteries have  greater charge




capacity than Ni-Cd batteries of a comparable size (SAFT  1989a, Moli 1989).




However, lithium batteries are currently much more expensive (at least twice




the price) than Ni-Cd batteries and they are more sensitive to  abuse such as




overcharging.  Advantages of lithium rechargeable batteries include their




light weight, ability to provide energy in sub-freezing temperatures, and very




high efficiency.  Possible applications for lithium batteries include portable




cellular phones, lap-top computers, portable radios,  and military applications




(Panasonic undated).




      Another battery technology currently in use is  the silver-zinc system.




This system,  which has a high energy density,  is used primarily (90 percent of




the time)  for military and space applications  (Kirk-Othmer 1978, SAFT 1989c) .




There are  many limitations that may restrict its use  in consumer applications




such as high cost and limited service  life.




      The  nickel-zinc cell is a potential  substitute  that  offers a  charge




density greater than that available from nickel-cadmium batteries,  but  at  a




lower cost than silver-zinc.   Although its performance is  not as high as  its




silver-based counterpart,  it is also not subject to the wide  fluctuations  in




price resulting from speculation in precious metals markets.




      An additional battery system that currently is  found only  in  exotic




applications  (e.g.  satellite applications) is  the  nickel-hydrogen cell.  The




hydrogen in the cell is in the gaseous form, and the  operating pressure is





                                    - xxi  -

-------
much higher than other cells, ranging from 3-20 times atmospheric pressure, as




compared to 0-3 atmospheres for a nickel-cadmium cell.  Because of these high




operating pressures, construction is labor-intensive and very expensive.




      Glass and Ceramic Products




      The use of lead in glass products is primarily due to  its good




performance properties and low cost relative to potential substitutes.  As an




intermediate, lead monoxide adds to the brilliance of glass  products, and as a




modifier, it lowers the melting temperature, thereby simplifying glass




processing.  Lead-containing glass also can shield high energy radiation and




the high refractive index of lead yields excellent properties for optics and




for hand-formed art ware.  Cadmium in glass and ceramic products is used as a




pigment in a glaze, as a colorant in the glass itself, or as a phosphor (EPA




1989).




      Table SR-6 lists potential substitutes for lead and cadmium in glass and




ceramic products.  The potential substitutes for lead- and cadmium-based




glass/ceramic products usually involve switching to alkaline earth metals




 (primarily strontium and barium) and zirconium, that are expensive in




comparison to lead and cadmium.  The performance properties  of the potential




substitutes for lead-based glass/ceramic products lack the refractive indices,




 the  radiation absorption characteristics, and the ease of processing of lead-




based glass/ceramic products.  There are also reports of supply problems with




 strontium  and zirconium  (Corning 1989c).




       Brass and Bronze Products




       Lead is generally  added  to brass to improve the free machining




 characteristics of  the alloy.  Lead also may be present as an impurity in some




 brass products due  to  the  lead content of scrap materials used in the
                                    -  xxii  -

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                                     Table SR-6.  Potential  Substitutes  for  Lead and Cadmium in Glass and Ceramics
    Lead and Cadmium Use
                                                     Potential Substitute
                                                                                                                 Performance Comments
 Glass
    Television Parts:

       Neck and funnel
        (28 and 22 percent PbO
       respectively)

       Faceplate (panel)
        (2X PbO)

    Leaded Glass:

       X-ray shielding


       Neon/fluorescent tubing

       Light bulb
       Optical Glass
Ceramics
    Glazes/enamels
   PZT/PZLT  (68X PbO)
 Strontium
 Barium
 Zirconium
 Thicker glass


 Strontium/barium

 Cerium

 Alkaline earth metals

 Barium/zinc oxides
 zinc, lithium, and barium oxides


 Zirconium dioxide


 Chrome tin salt

 Barium lead titanate
 (10X lead)


Quartz


Rochelle Salts
 Processing problems, lower durability,
 larger quantity required.
                                                     Supply problem, marginal cost difference  (6
                                                     percent higher).
 Expensive;  increased space requirements and
 decreased visual  clarity.

 Processing  problems
             *
 Under  development; processing problems.

 Under  development; processing problems.

 Lower  achievable  index of  refraction  than
 with lead.  Commercially available.


 Satisfactory brilliance and alkali
 resistance; some application problems.

 Color  instability.

 Not as piezoelectrically efficient; cannot
 be used in temperatures over 100°C; 25
 percent less expensive.

 Not as piezoelectrically efficient; 3-4
 times more expensive.

Not effective in humid environment; more
piezoelectrically efficient.
Sources:  Blanche 1989;  Corning 1989a,  1989b,  1989c, 1989d; Degussa 1989; Piezo Kinetics 1989; Sylvania 1989a.
                                                                    -  xxiii  -

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manufacture of brass products.  Lead is present, therefore, in virtually all




kinds of brass at least to a small degree.  Leaded bronze may contain up to 30




percent lead.  The lead is included because it  improves workability and




conformability (Copper Development Association  1989) .




      Two methods can be used to substitute away from lead  in brass and




bronze.  Alternative metals can be incorporated with copper to create alloys




with similar properties to lead-containing products, or alternative materials




(e.g., plastics or steel) can be used  in  the final products.




      Table  SR-7  identifies the potential substitutes by use area  for leaded




brass and bronze  products.  The choice of potential  substitute depends to  a.




large extent on the properties that  the consumer requires most and which,  if




any, properties offered by leaded brass and bronze can be forfeited.




Different substitutes will be chosen if hardness, color, strength, or another




property  is  critical or must  remain  constant.'  Bearings and fittings made  from




unleaded  tin bronze and aluminum bronze are already  used in heavier load




applications for  which leaded bronze is not hard enough.  Machinable leaded




brass  and bronze  used  for  screw parts  and plumbing fixtures can be substituted




by other  copper  alloys to  a  large  degree. The  addition of  tellurium,




 selenium,  or sulfur offers  the possibility of  improving the machining




 characteristics  of copper  and its  alloys  without the use of lead  (Copper




 Development Association  1989,  Kirk-Othmer 1978).




       Other potential  substitutes  for leaded brass can replace specific end




 products.  For example,  some plumbing fixtures  and valves  currently




 manufactured with brass  or bronze  may be  replaced by PVC or other  plastic




 materials,  but these  materials are not suitable for  the bulk  of brass and




 bronze applications.   Machined screws may be  replaced by  steel screws or




 another machinable metal depending on the importance of  corrosion  resistance.
                                    - xxiv -

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                 Table SR-7.   Potential  Substitutes for Lead-based Brass and Bronze Products
Lead Use
 Potential Substitutes
                                                                            Performance Comments
Machined Products
      Plumbing Fixtures
      Machine Screw Parts
Bushing/Bearing Products
Steel3

PVCa



Tellurium bronze



Selenium bronze



Sulfur bronze



Tin bronze

Aluminum bronze

Manganese bronze
 Poor  corrosion  resistance

 Not able  to handle  all
 applications; poor  shear
 resistance.

 Not commercially available;
 marginal  difference  in
 mach inab i 1 i ty.

 Not commercially available;
 marginal  difference  in
 machinability.

 Not commercially available;
 marginal  difference  in
 machinability.

 Harder, requires lubrication.

Harder, requires lubrication.

Harder, requires lubrication.
• Steel and PVC .are a different  class  of potential  substitute  in  that  they  replace  the  end-product uses  of
brass and bronze instead of the  use of lead in brass and bronze.

Sources:  Copper Development Association 1989,  Nielsen undated, Kirk-Othmer 1978.
                                                  - xxv -

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      Cadmium Plated Products

      Cadmiua plating is used on fabricated steel and cast iron parts and can

be electroplated on plastics or metal in some appliance and consumer

applications.  Cadmium is used because it has a combination of properties:

natural lubricity, corrosion resistance to salt water and alkalis, high

deposition rate on application, good solderability and ductility, and a long-

lasting silvery-white luster.

      Cadmium plating is used to protect bolts and screws used in marine
                                                                        V;
applications from corrosion due to prolonged exposure to moisture and salt.

In general, cadmium plated products have a longer service life due to their

corrosion resistance and natural lubricity that help in applications where

mechanical seizures would impair function.  Automotive uses such as seat belt

fasteners and brake linings are examples of applications for which these

features are important.  Cadmium plated fasteners also are used because their

natural lubricity reduces the torque experienced during fastening, thereby

reducing the potential for fatigue and failure.

      Potential substitutes for cadmium in plating operations can be

classified into two groups:   (1) alternative materials and technologies for

applications that do not require the properties imparted by cadmium plating

and  (2) alternative coatings with similar properties that can be used in place

of cadmium.  Table SR-8 contains a list of the potential substitutes for

cadmium in plating operations.

      The substitution that has already taken place in the majority of

household applications has used alternative materials.  Cadmium plated parts

 in washing machines and dishwashers have been replaced to a great degree by

 the  increased  use of plastic  construction that does not require cadmium plated

bolts to hold  the frames  together  (EPA 1989).

                                    - xxvi -

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                           Table SR-8.  Potential Substitutes for Cadmium Plating
Cadmium Use
Potential Substitutes
                                                                                Performance
Electronics (chassis)
Resinous printed circuit boards8
Substitution already occurring;
superior technology.
Fasteners (nuts, bolts)
Plastic construction3



Zinc plating



Tin plating


Gold plating


Chrome plating
Substitution already occurred in
consumer household appliances,
but not possible in most cases.

Lower corrosion resistance, loss
of lubricity, loss of
solderability.

Good solderability, poor
corrosion resistance.

Good corrosion resistance, very
expensive, poor wear resistance.

Good wear properties, better
corrosion resistance for acids,
lower corrosion resistance for
salts and neutral pH.
8 Plastic construction and resinous printed circuit boards are a different class of substitute in that they
eliminate the need for the end-product use of cadmium plated parts.

Sources:   AESF 1989,  Cadmium Council  1989. Iron Age 1980, Kirk-Othmer 1978.
                                                 -  xxvii -

-------
      Additional substitutions for cadmium plating may use similar technology




or alternative coatings.  The choice of replacement plating will depend on




which properties of cadmium coating are most important.  Although inferior in




terms of solderability and lubrication, zinc is already used whenever possible




because of reduced health and environmental concerns compared to cadmium  (AESF




1989).  Electroplated tin and gold are readily solderable, although gold  is




very expensive.  Tin is not effective in corrosion resistance, but the




development of tin-zinc alloys and a zinc-nickel alloy as possible substitutes




for cadmium is progressing (AESF 1989, Kirk-Othmer 1978).  Chrome plating also




is an economical process to improve corrosion resistance of steel where




appearance is not important.  Chrome offers the advantage of a low friction




surface and good wearability, but does not offer the same corrosion resistance




as cadmium (Iron Age 1980, AESF 1989).




      Collapsible Tubes



      Collapsible tubes are used to dispense a number of products ranging from




medicines to  epoxy resin adhesives.  While these tubes can be manufactured




from  a variety of materials,  lead tubes are used to dispense corrosive




products  (lead is difficult to corrode) or to satisfy customer packaging




preferences.  Lead tubes represent a very small fraction  (less than one




percent)  of  the  tube market.  Of the lead tubes currently manufactured, most




are used  for artists colors and the remainder for corrosive glues.



       One of the possible  substitutes  for lead tubes is aluminum tubes with




phenolic  epoxy  lining.  This  aluminum  technology does not differ in cost  and




 offers similar performance to the lead tubes.  Another potential substitute




 technology,  laminate  tubes manufactured with alternating  layers of plastic and




 aluminum,  also  can  replace lead tubes  and have similar costs  (see Table SR-9).
                                   - xxviii -

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      Other Products




      There are a variety of other products that contain lead and/or cadmium




that are disposed of in MSW facilities.   These products,  however, account for




a very small percent of the total amount disposed.   The Other Products




category includes foil wine wrappers,  used oil,  rubber (elastomers),  and




electric blankets/heating pads.   Potential substitutes for these lead and




cadmium use areas are presented in Table SR-9.
                                   - xxix

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                               Table Sft-9.  Potential Substitutes for Miscellaneous Products Containing Lead or Cadmium
      Lead or Cadmium Use
                                                    Potential Substitute
                                                                                                           Performance Contents
Collapsible Tubes
Aluminum lined with phenolic epoxy

Plastic and aluminum laminates
Similar in performance to lead tubes.

Similar in performance to lead tubes.
foil Vine Wrappers
Plastic

Aluminum foil
Similar cost and performance to lead.

Similar cost and performance to lead.
Used OiI
Zinc organo-phosphates
Iron and zinc chlorides
Iron sulfides
Similar cost and performance to lead-
cadmium-based products.
Rubber (elastomer) Products
        Pigments*
        Vulcanizing agents
Dithiocarbamates (bismuth, copper, selenium,
tellurium, zinc, piperidium, thiazoles)
Cost and performance of potential substitute
varies depending on formulation.
Printing Inks
Dialyrid yellow
                                                    Dialyrid orange
More expensive than lead chromate and lead
sulfochromate.  Less lightfast and opaque
than lead chromate and lead sulfochromate.

More expensive than lead chromate and lead
sulfochromate.  Less lightfast and opaque
than lead chromate and lead sulfochromate.
Electric Blankets and Heating Pads
Undetermined1*
                                                                                                         Undetermined
* For a discussion of potential substitutes for  pigments  in  rubber,  see  previous  discussion of  pigments in the Plastics section.

b Although the use of cadmium-containing wires for electric  blankets and heating  pads  has not been characterized and potential  substitutes have not
been evaluated, it is likely that other copper alloy wires will  be able  to fully  supplant cadmium-containing wires for this use.

Sources:  ANPA 1989; BASF 1989a; EPA 1989; Kirk-Othmer 1983; NAPIN 1989; Teledyne 1989;  Wine Institute 1989.
                                                                      -  xxx  -

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REFERENCES

ADL.   1990.   (November  15).   Lead Use  and  Substitutes.   Report  to  Lead
Industries Association.   Prepared by Arthur  D.  Little,  Inc.,  Cambridge,  MA.

AESF.   1989  (July  31).  American Electroplaters  and  Surface Finishers  Society.
W. Safranek.  Orlando,  FL.  Transcribed  telephone conversation  with  Louis
Gardner,  ICF  Incorporated, Fairfax, VA.

ANPA.   1989a  (August  14).  American Newspaper Publishers Association.   G.
Cashau, Director of Technical Research.  Reston, VA.  Transcribed  telephone
conversation  with  Thomas  Hok, ICF Incorporated,  Fairfax, VA.

Arconium.  1989 (July 24).  J. Hamilton, Sales Representative.  Providence,
RI.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated
Fairfax, VA.

Argus.  1989a (May 10).   M. Croce.  New York, NY.  Transcribed  telephone
conversation with Mark Wagner, ICF Incorporated, Fairfax, VA.

Argus.  1989b (May 11).   D. Stimpfl.  New York, NY.   Transcribed telephone
conversation with Mark Wagner, ICF Incorporated, Fairfax, VA.

Argus.  1989c (May 17).   D. Brilliant.   New York, NY.  Transcribed telephone
conversation with Mark Wagner, ICF Incorporated, Fairfax, VA.

BASF.   1989a  (May 16).  Basic Organics Group.  Transcribed telephone
conversation with Tanya Yudleman,  ICF Incorporated,  Fairfax,  VA.

BASF.   1989b  (August 14).   R.  Wagner,  Manager in Charge of Product Compliance,
BASF, Clifton, NJ.   Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Bayer-Mobay Corporation.  1989 (May 16).   Transcribed telephone  conversation
with Tanya Yudleman,  ICF  Incorporated,  Fairfax,  VA.

Bedford Chemical.   D.  Gauw.  1989  (May 4).   Bedford  Chemical,  Division of
Ferro Corporation.   Bedford,  OH.   Transcribed telephone conversation with Mark
Wagner, ICF Incorporated,  Fairfax,  VA.

Blanche, S.T.  1989.   "Chrome-Tin  Pink Glazes,"  Ceramic Engineering Scientific
Proceedings.  Vol.  10,  pp.  65-68.

Cadmium Council.   1989 (July 27).   H.  Murrow.   New York,  NY.   Transcribed
telephone conversation with Louis  Gardner,  ICF Incorporated Fairfax,  VA.

Chemical Business.   1989  (July/August).   "The Assault on Batteries,"  p.  35-36.

CMI.   1989a (June 1).   Can Manufacturers  Institute.   D.  Karmol.  Counsel.
Washington,  DC.   Transcribed telephone  conversation with Thomas  Hok,  ICF
Incorporated, Fairfax, VA.
                                   -  xxxi -

-------
CMI.  1989b (July 28).  Can Manufacturers Institute.  D. Kannol.  Counsel.
Washington, DC.  Transcribed telephone conversation with Thomas R. Hok,  ICF
Incorporated, Fairfax, VA.

Copper Development Association.  1989 (July 21).  A Cohen.  Greenwich, CT.
Transcribed telephone conversation with Louis Gardner, ICF Incorporated,
Fairfax, VA.

Corning Glass.  1989a (July 21).  T. Seward.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, -VA.

Corning Optics. R. Thompson.  1989b  (July 21).  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  D. Lopata.  1989c (May 30).  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  J. Connelly.  1989d  (July 26).  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Degussa Corporation.  D. Gillier.  1989 (August 14).  Transcribed telephone
conversation with Louis Gardner, ICF Incorporated, Fairfax, VA.

EPA.  1989  (January).  U.S. Environmental Protection Agency.  Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities,
1970 to 2000.  Prepared by Franklin Associates, Ltd.  Prairie Village, KS.

EPA.  1990  (November).  U.S. Environmental Protection Agency.  Summary of
Pollution Prevention Act of 1990.  Prepared by the Office of Pollution
Prevention, U.S. EPA.  Washington, D.C.

Franklin Associates.  1990 (August).  Characterization of Lead in Plastic
Products in Municipal Solid Waste, 1970 to 2000.  Prairie Village, KS.

Indium Corporation of America.  1989a (July 19).  R. Altieri.  Applications
and Engineering, Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1989b (July 28).  R. Altieri.  Applications
and Engineering, Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1989c (August 15).  J. Ferriter.
Applications and Engineering.  Utica, NY.  Transcribed telephone conversation
with Thomas Hok, ICF Incorporated, Fairfax, VA.

IPC.  1989a  (July 20).  Institute of Printed Circuits.  D.  Bergman.   Chicago,
IL.  Transcribed telephone conversation with Thomas R. Hok, ICF Incorporated,
Fairfax, VA.

IPC.  1989b  (July 28).  Institute of Printed Circuits.  D. Bergman.   Chicago,
IL.  Transcribed telephone conversation with Thomas R. Hok, ICF Incorporated,
Fairfax, VA.

                                   -  xxxii  -

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Iron Age.  1980 (January 14).  Cadmium's Plight Opens Field to Alternative
Coatings,  p. 50.

Kapp Alloy and Wire, Inc.  1989 (July 19).  D. Porter, Technical Director,
Altoona, PA.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Keeler, R.  1987 (July).  "Specialty Solders Outshine Tin/Lead in Problem
Areas."  Electronic Packaging and Production, pp. 45-47.

Kirk-Othmer.  1978.  Encyclopedia of Chemical Technology.  John Wiley and Sons
Publishing Co., Inc.  Volume 3, pp. 674-77; Vol. 3, pp.  569-639; Volume 6, p.
166; Volume 7, p.  45; Volume 8, pp. 827-869; Volume 15,  pp. 241-274.

Kirk-Othmer.  1983.  Encyclopedia of Chemical Technology.  John Wiley and Sons
Publishing Co.   Vol. 6,  Vol. 14, pp. 168-183, 493-496; Vol.  18, pp. 184-206;
Vol. 20, p. 338.

Manko, H.H.  1979.   Solders and Soldering.  Published by McGraw-Hill Book
Company, New York,  NY.  Second edition.

Moli Energy.  1989 (January).  Product literature on Molicel Lithium
batteries.

NAPIM.  1989 (August 14).  National Association of Printing Ink Manufacturers.
P. Volpe, Technical Coordinator.  Westchester, NY.  Transcribed telephone
conversation with Thomas Hok, ICF Incorporated, Fairfax, VA.

NFPA.  1989 (July 31).  National Food Processors Association.   E. Elkins.
Washington, DC.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Nielsen, WD.  Undated.  Metallurgy of Copper Base Alloys.  Casting Engineering
& Foundry World.  Reprint.

Palmer, J.G.  1988 (September).  Executive Vice President, Pacific-Dunlop-GNB,
Incorporated, St.  Paul, MN.  "A Cleaner Environment:  Removing the Barriers to
Lead-Acid Battery Recycling."  Written in collaboration with M.L. Sappington,
P.E., President, Lake Engineering, Incorporated, Atlanta, GA.

Panasonic.  Undated.  "Batteries," a publication of Panasonic, Secaucus, NJ.

Piezo Kinetics Inc.  1989 (May 30 and July 27).  R. Turner.  Transcribed
telephone conversation with Peter Weisberg, ICF Incorporated,  Fairfax,  VA.

Plastic Additives Handbook.  1987.  Hanser Publishers.  Munich, Germany.

SAFT America.  1989a  (July 14).  G. Lupul.  Maryland.  Transcribed telephone
conversation with Donald Yee, ICF Incorporated, Fairfax, VA.

SAFT America.  1989b  (July 14).  G. Lupul.  Maryland.  Transcribed telephone
conversation with Donald Yee, ICF Incorporated, Fairfax, VA.
                                  - xxxiii -

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SAFT America.  1989c (August 15).  P. Scardaville, Director of Engineering.
Valdosta, GA.  Transcribed telephone conversation with Alex Greenwood, ICF
Incorporated, Fairfax, VA.

Sylvania and Laxman Ltd.  1989a  (June 1).  R. Marlor.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Sylvania and Laxman, Limited.  1989b (July 18).  R. Marlor.  Manager, Glass
and Ceramics.  Salem, MA.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Sylvania and Laxman, Limited.  1989c (July 28).  R. Marlor, Manager, Glass and
Ceramics, Salem, MA.  Transcribed telephone conversation with Thomas R. Hok,
ICF Incorporated, Fairfax, VA.

Talco Metals.  1989 (July 18).  C. Carabello, Sales Representative.
Philadelphia, PA.  Transcribed telephone conversation with Thomas R. Hok, ICF
Incorporated, Fairfax, VA.

Teledyne Packaging.  1989 (May 31).  K. Barry.  New Jersey.  Transcribed
telephone conversation with Thomas Hok, ICF Incorporated, Fairfax, VA.

Wine Institute.  1989 (June 1).  W. Lee.  San Francisco, CA.  Transcribed
telephone conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Yardney Battery.  1989a  (July 13).  T. Aretakis.  Connecticut.  Transcribed
telephone conversation with Donald Yee, ICF Incorporated, Fairfax, VA.

Yardney Battery.  1989b  (July 20).  D. Wissocker.  Massachusetts.  Transcribed
telephone conversation with Donald Yee, ICF Incorporated, Fairfax, VA.
                                   - xxxiv -

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I.   INTRODUCTION

      The use of lead- and cadmium-containing articles that ultimately are

disposed of in municipal solid waste (MSW) facilities is the focus of a joint

project by the Office of Toxic Substances and the Office of Solid Waste of the

U.S. Environmental Protection Agency.  The use and substitutes analysis

provided in this report characterizes and discusses technologically feasible

substitutes for lead and cadmium in products identified in an earlier EPA

report entitled "Characterization of Products Containing Lead and Cadmium in

Municipal Solid Waste, 1970 to 2000."  The products discussed in this report

are as follows:

                  plastics;
                  pigments;
                  solder;
                  nickel-cadmium batteries;
                  glass and ceramic products;
                  brass and bronze products;
                  cadmium  plated products;
                  collapsible tubes;
                  lead-acid batteries; and
                  other products.

Table  1  identifies the amount of lead and cadmium in each of these product

areas  discarded in MSW in  1986.  As  the  table indicates, the majority of

discards  is  in the battery, plastics, pigments, solder, and glass categories.

These  uses account for 99  percent of the lead"  and 89 percent of the

cadmium  disposed  of  in MSW.
      *  Other products containing lead and/or cadmium include rubber products,
 printing inks,  used oil,  foil  wine  wrappers, and electric blankets and heating
 pads.

      **  Lead acid batteries accounted for 138,043 tons of lead discards in
 1986,  about 2/3 of the  total  lead discards  in MSW  (EPA  1989).  This use of
 lead is not a  major focus of  this report, however, because  lead-acid batteries
 have been characterized in other reports  prepared  for and by EPA  (e.g., Palmer
 1988)  and because  substitutes  for this  battery  system are not currently
 available.

                                     - 1  -

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    Table 1.  Discards of Lead and Cadmium by Use Area in MSW  in 1986
Product Area
Lead Acid Batteries
Plastics
Pigments3
Solder
Nickel/Cadmium Batteries
Glass and Ceramic Products
Brass and Bronze Products
Plated Products
Collapsible Tubes
Rubber Products
Other Products6
Lead Discards
(tons)
138,043
3,174
1,131
8,369
0
60,714
321
0
639
70
671
Cadmium Discards
(tons)
0
564
70
0
927
29
0
185
0
6
1
a Discards of pigments do not include pigments consumed in plastics,
glass/ceramic products, or rubber products.  These discards are
covered in the sections on plastics, glass/ceramic products, and
rubber products.

b Other products include used oil,  foil wine wrappers,  electric
blankets and heating pads, and television and radio chassis.  279
tons of lead were discarded as part of television and radio chassis,
but future discards are expected to be zero.

Source:  EPA 1989, Franklin 1990.
                                  - 2  -

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      Lead and cadmium have been used in the products identified in this




report as additives, components, and coatings to improve performance, fulfill




certain customer preferences, and to impart certain characteristics to end




products based on the physical/chemical properties of the metals and/or




compounds made from them.  The use of lead- and cadmium-containing products is




characterized for each product area with emphasis on the critical properties




that they provide to finished products.




      Potential and existing substitutes that can replace lead and cadmium in




these uses are characterized to the extent that information is available from




secondary data sources.  Technical feasibility is the only basis used in th-is




analysis to identify substitutes.  Thus, only in cases where no alternative is




currently available that imparts the same properties provided by lead or




cadmium  does this report fail to present potential substitutes.  Information




on potential substitutes was identified from published sources (standard texts




and journal articles)  and  conversations with industry contacts.




      Some qualitative  cost information is presented for potential substitutes,




but estimates of  the likely market shares that potential substitutes would




absorb  in the event that lead and cadmium products were no longer available




have  not been developed  in this  study.  However, the information presented




here  along with other  background data developed during the project provides a




solid foundation  for estimating market shares and other more detailed economic




 information for potential  substitutes.




       A. Limitations




       This  report should be considered as a  preliminary analysis due to the




 limitations of  its  scope.   EPA  has not performed primary research to identify




 the substitutes  for lead and cadmium described  in this report.  Only




 substances  identified  in published  sources  or by  industry contacts and that





                                     - 3 -

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 were  known or considered to be possible substitutes have been included in this

 analysis.   Because  this  report characterizes  substitutes for both lead and

 cadmium  products, lead and cadmium products are  not considered as substitutes

 for each other although  these  products  sometimes may be  technically feasible

 options.   Furthermore, the substitution in this  report is  based only on

 technical  feasibility  and  does not quantitatively assess economic factors that

 affect substitution or the effect  of potential substitutes on end products

 (e.g., different service lives for substitute products).   This  report,

 therefore,  is  not intended to  draw conclusions about  the viability of actual

 substitution.  No economic  analysis has been performed to  estimate the  impacts

 of substituting for lead and/or cadmium products.

      In addition, toxicities  of substitutes are not discussed  in  this  report

 and toxicity was not a criteria for identifying potential substitutes. Many  of

 the classes of chemicals assessed have intrinsic toxicities that would be  of

 great concern  in other parts of the manufacturing processes where  there wouid

 be human or environmental exposure to more bio-available  forms of the chemical

 or chemicals.   A more focused, in-depth substitute  characterization for each

 chemical substitute in each use area would be  required to adequately assess

 the hazard presented by potential substitutes.

      B.   References

 EPA.   1989 (January).   U.S. Environmental Protection Agency.   Characterization
 of Products Containing Lead and Cadmium in Municipal Solid  Waste Facilities,
 1970 to 2000.  Prepared by Franklin Associates  Ltd., Prairie  Village,  KS.

 Franklin Associates.  1990 (August).  Characterization of  Lead in Plastic
 Products in Municipal Solid Waste,  1970 to 2000.   Prairie Village,  KS.

 Palmer,  J.G.  1988 (September).  Executive Vice President,  Pacific-Dunlop-GNB,
 Incorporated, St.  Paul, MN.  "A Cleaner Environment:  Removing the Barriers to
Lead-Acid Battery Recycling."  Written  in collaboration with  M.L.  Sappington,
P.E.,  President, Lake  Engineering,  Incorporated,  Atlanta, GA.
                                    - 4 -

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II.  PLASTICS -

      A.  Overview of the Plastics Industry

      Plastics can be categorized into two major groups, thermoplastic and

thermoset, based on how the plastic reacts when heated.  Thermoplastic resins

can be melted and solidified in a reversible process, while thermosetting

resins initially liquify with heat, but then permanently solidify with further

heating.  Because of the advantages associated with using thermoplastic resins

(i.e., that they can be reworked or reformed and are therefore easier to

handle), over 90 percent of all resins produced are thermoplastic (Kirk-Othmer

1983).  Table 2 identifies some of the most common thermoplastic resins.

      Thermosetting resins are exemplified by certain types of polyesters and

polyurethanes, as well as phenol-formaldehyde, urea-formaldehyde, and

melamine-formaldehyde resins.  Thermoset resins are characterized by

irreversible bond formation  (cross-linking) between polymer chains that occurs

during  the heat curing stages of processing.  Table 2 identifies the major

categories of thermosetting  resins.

      Processing of resins takes place through a number of different

techniques including extrusion, molding, thermo- or vacuum-forming, casting,

and  calendaring.  Approximately half  of all resins are converted into products

by extrusion.  The extrusion process  is continuous, making products of uniform

cross-section and  infinite length  that can be rolled or coiled, cut into

lengths,  or  otherwise packaged.  Typical products that are made by extrusion

 include film, sheet, pipe, tubing, profiles,* coated wire, and coated paper

 (Kirk-Othmer 1983).
      *  Profiles  are  typified by  such products as channels, gaskets, decorative
 trim, siding panels, window frames,  and other rigid structures used in  indoor
 and outdoor construction and building.

                                     -  5 -

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Table 2.  Representative Thermoplastic and Thermosetting Resins
          Amorphous* Thermoplastic Resins

               Acrylonitrile-butadiene-styrene  (ABS)
               Cellulose  acetate
               Polycarbonates
               Polyacrylates and methacrylates
               Polystyrene
               Polyvinyl  chloride  (PVC)
               Styrene-acrylonitrile  (SAN)

          Crystallineb Thermoplastic Resins

               Polyethylene, low density  (LDPE)
               Polyethylene, high density  (HDPE)
               Polypropylene
               Polyacetals
               Nylons
               Polyesters0
               Fluoropolymers

          Thermosetting Resins

               Phenol- formaldehyde
               Urea-formaldehyde
               Melamine•formaldehyde
               Polyesters
               Polyurethanes
          ' Amorphous thermoplastics are character-
          ized by no distinct melting and freezing
          points.

          b Crystalline thermoplastics have  well
          defined melting and freezing points.

          c Some polyesters are thermoplastics,
          while others (e.g., phenol-formaldehyde
          resins) are thermosetting.

          Source:  Kirk-Othmer 1983.
                             -  6  -

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      Molding is a process by which molten thermoplastic resins are injected

under pressure into a mold and cooled until the article can be removed from

the mold without distortion.  Thermoforming of amorphous resins, e.g.,

polystyrene, polyvinyl chloride (PVC),  and polymethyl methacrylate, is also

common, as is casting of acrylates between two glass sheets.  Calendaring

operations consist of making sheets from PVC and acrylonitrile butadiene -

styrene (ABS) resins that are used in the manufacture of luggage, wall

paneling,  and furniture.  Thermosetting resins are processed almost

exclusively by molding operations, although some flexible polyurethane foams

are processed in the form of a slab (Kirk-Othmer 1983).

      B.  Additives Used in the Processing of Plastics

      A wide range of plastic processing chemicals (additives) are available

to serve various functions in some or all of the resin types identified in

Table 2.  Additives can impart a particular characteristic to the end product

or may be required to preserve the integrity of the plastic resin during

processing or use.  The range of all chemical additives  (lead and cadmium as

well as non-lead/cadmium additives) are grouped into the following categories

(Radian 1987) :

                  Antioxidants;
                  Antistatic agents;
                  Blowing agents;
                  Catalysts and cure agents;
                  Colorants;
                  Coupling agents;
                  Fillers and reinforcers;    <
                  Flame retardants;
                  Free radical initiators;
                  Heat stabilizers;
                  Lubricants and mold release agents;
                  Plasticizers;
                  Preservatives;
                  Solution modifiers; and
                  UV stabilizers.
                                     -  7  -

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      Fillers and reinforcers, plasticizers, and flame retardants make up the




vast majority of additives consumption in the plastics industry, accounting




for almost 92 percent of consumption by weight (Modern Plastics 1982).




Colorants and heat stabilizers, major compounds formulated with lead and/or




cadmium, account for 3.9 and 1.0 percent by weight of all plastic additives




consumption, respectively.




            1.  Additives Containing Lead and/or Cadmium




            Additives that contain lead and cadmium do not account for a large




proportion of total additive consumption,  but due to the large volume of




plastic produced annually, approximately 57 billion pounds in 1988,  a




substantial amount of these products is consumed (Modern Plastic 1988).




Section C of this chapter provides an in-depth discussion of actual




consumption of these lead- and cadmium-containing products.




      In addition to heat stabilizers and colorants,  there is a small amount




of lead and cadmium present in certain polymerization catalysts and




lubricants.  Lubricants based on metallic  soaps,  including lead and  cadmium




stearates as well as the more common calcium,  aluminum,  magnesium, and zinc




stearates,  are used with many types of resins  (including PVC resins)  where




they also act as heat stabilizers.  Lead and cadmium may also be present  in




certain metal oxide and other catalysts,  either incorporated intentionally or




present as  impurities in other metal-based catalysts  (Radian 1987).   These




lubricant and catalyst uses of lead- and cadmium-based products account for  a




small amount of the lead- and cadmium-based plastic additives and hence,  are




not discussed in the remainder of this report.
                                    - 8 -

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                  a.  Lead- and Cadmium-containing Pigments Used with Plastic
                      Resins

                  Colorants used in plastic resins number into the hundreds.

Combined with the wide variety of polymers, the permutations that exist in

coloring plastics are enormous.  In many cases, "color houses" exist to match

a given polymer with a compatible colorant.  While hue and shade requirements

eliminate a fair share of the possible combinations of colorants and plastics,

solubility of the colorant in the medium is also important in the selection

process.  Solubility determines whether a dye or a pigment is used.  If the

colorant must be soluble, a dye is normally chosen;  if solubility is not a

factor, pigments are usually used because they are less expensive (Plastics

Engineering Handbook 1987).

      Dyes are soluble in plastics and present minimal problems when mixed

with a polymer.  Pigments, on the other hand, are supplied in the form of a

finely ground powder and must be dispersed or distributed evenly in the

polymer.  Dispersion of a pigment is a physical process consisting of a number

of separate steps.  First, the dry powder must be broken down into the desired

particle size; second, the powder is blended with a resin or binder so that

the pigment is "wetted" and a homogenous mix is produced; and finally, to

counteract the cohesive forces that normally try to reagglomerate the

particles, the dispersion must be stabilized.  Dispersability is also

important since  it  is one  of the few ways to broadly classify pigments into

either  inorganic or organic* (Plastic Additives Handbook 1987).   Generally,
      * Organic pigments, by definition, are compounds containing carbon and
 although some  organic  molecules may  contain metal or metal salts, the
 inorganic component  is considered secondary (responsible more for undertones
 than primary hue  color)  (Brannon  1988).   In addition, not only lead and
 cadmium  ions,  but other metal  ions could  impart  the desired properties to
 these organic  pigments.   Lead  and cadmium based  organic pigments, therefore,
 are not  considered significant products and are  not discussed in this report.

                                     - 9 -

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inorganic pigments have a fairly uniform particle size and are easier  to




disperse than organic pigments, which tend to have non-uniform particle size




(Plastics Engineering Handbook 1987).




      Other performance properties that must be considered in the selection of




a colorant include heat stability, lightfastness, opacity, and chemical




resistance.  Lead and cadmium pigments have most of the same characteristics




as other inorganic pigments for these properties and so this discussion




focuses primarily on the properties for inorganic pigments in general.  Where




possible, indications are also given as to the specific performance properties




of lead and cadmium pigments.




      During the manufacturing or processing of colored plastics, heat can be




the cause of coloristic change.  Heat or thermal stability is not only




dependent on the processing temperature, but also the duration of exposure and




the acceptable shade tolerance (Plastic Additive Handbook 1987).   In general,




inorganic pigments possess greater heat stability than organic pigments,  which




degrade or sublime when exposed to high temperatures  for  extended periods  of




time (Brannon 1988).




      Lightfastness of plastics is another important  characteristic  of




pigments and is defined as the probability that a plastic will lose  its color




intensity due to light,  especially sunlight.   This property  is not solely




dependent on the pigment,  but  is  dependent on the polymer system  as  well.




Lightfastness of a colorant is analyzed, therefore, in terms  of the  full




colorant/plastic system (Plastic  Additives Handbook 1987).   In addition, color




loss due to exposure to solvents,  acids, or alkalies  is not just  a chemical




property of the pigment,  but is attributable  to the polymer  system (Brannon




1988).   In general,  neutral organic pigments  exhibit  good chemical resistance,
                                    .  10 -

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whereas varying degrees of chemical sensitivity exist for inorganics and

organic metal salts.

      Opacity and hiding power also may be important characteristics for

pigments.  These terms usually are used to describe the ability of a pigment

to scatter light and hide the resin matrix (Brannon 1988).  Whether a pigment

is described as being opaque, semi-opaque, or transparent depends on the

pigment's refractive index.  Differences in the refractive indices between

pigments and polymer systems may result in a greater  scattering of light,

which gives greater hiding power or opacity.  In general, the larger pigments

(inorganics), exhibit hiding power, but smaller pigments (organics), have

greater transparency (Brannon 1988).  Table 3 provides some of the performance

characteristics for lead and cadmium-based pigments.

                        i.  Lead-containing Pigments

                        Lead-based pigments used in plastics include chromates

and molybdate oranges.  The plastics industry has been cited as one of the

largest consumer uses of lead chromate pigments* (EPA 1989).   Currently,  the

use of lead-based pigments is declining because of health-related concerns

(EPA 1989).  Most users of these pigments have cited the relatively low cost

(about $2/pound in 1985 for molybdate orange) as a reason for their continued

use (Modern Plastics 1985).  The hue associated with lead-based pigments range

from greenish or light yellows to deep oranges and primrose for lead chromates

and from reddish yellows to red-shade oranges for molybdate orange.   Lead

pigments are inexpensive, provide good tint strength and have a high degree of

hiding power (opacity).  Lead chromates darken upon exposure to light,  heat,
     * Other uses of lead chromate pigments include interior and exterior
paints,  automotive finishes, textiles, and paper products (EPA 1989).

                                    - 11 -

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                                               Table 3.  Lead and Cadmium Inorganic Pigments and Their Performance Properties
Pigment
Lead:
Chromate
Sulfate
Molybdate
Chroeute + Icon Blue

Cadmium:
Sulfid.
Sulfide + Zinc
Sulfide + Selenium
Sulfide » Mercury
Heat Stability*
Hues Chemical Formula (*C)

Orange
Yellow-orange
Reddish orange
Greenish yellow to
Medium shades of olive green

Orange shade of yellow
Greenish yellow
Red and maroon
Reddish orange to bluish red
Pb
PbCr04 230-250
PbS04 230-250
PbMoO4 220-250
--

Cd
CdS 300
Cd + Zn
CdS + Se 300
CdS + Hg
Remarks on Performance0
Opacity/ (Compatible Polymer/
Lightfastness6 Chemical Resistance Hiding Power Resin)
Opaque
6-8 Sensitive to acids/bases PVC, LDPE + HOPE, PS -
6"8 Sensitive to acids/bases PVC, LDPE + HOPE, PS -
6-8 Sensitive to acids/bases PVC, LDPE + HOPE. PS -
-

Opaque
8 Sensitive to acids General suitability
8 Sensitive to acids General suitability
• For heat stability,  the temperature is stated at which no coloristic  changes  occurred  during  normal  dwell times  (approximately 5 minutes) in processing machines.

b Determination of lightfastness is carried out in accordance with DIN  53  389.   1  is  the lowest value;  *  has 8 times  the fastness level of 1;  the highest value is 8
testing not normally being carried out beyond this level.  See  Plastic  Additives Handbook (1987) for more information.

                        PS - polystyrene;  LDPE - low density polyethylene; PMMA -  polymethyl methacrylate;  HOPE =  high  density  polyethylene;  PVC - polyvinyl chloride
                        H-PVC m Unplasticized PVC.                                                                                                                   '
c Polymer Codes:
  Polymer Performance:   + denotes suitable/recommended;  - limited  suitability/recommended;  -  denotes  not  suitable/recommended;  ()  denotes  a qualification of the statement
                        * denotes caution is needed in the case  of HOPE  articles  sensitive  to distortion.

 Source:   Plastic Additives Handbook 1987,  Brannon 1988.
                                                                                 -  12  -

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(excess of 400*F) and in the presence of  sulfides.  They  also  demonstrate

sensitivity to acids and bases  (Brannon 1988).

                        ii.  Cadmium-containing Pigments

                        Cadmium-based pigments are actually classified as

sulfides, sulfoselenide or mercury complexes.  Pure cadmium sulfide is an

orange shade of yellow, but when zinc sulfide is added, the shade shifts to

greenish yellow.  On the other hand, cadmium sulfoselenide is  found when

selenium is added to the cadmium sulfide  compound producing a  red to maroon

shade.  Finally, mercadmiums are produced when mercury combines with the

cadmium sulfide compound yielding a reddish orange to bluish red hue.  Cadmium

pigments are expensive (about $15.00/lb.  for cadmium sulfide)  and the cost

continues to increase (BASF 1989).  For example,  the price of  cadmium pigments

rose 50 percent from September 1987 to September 1988 due to a 900 percent

increase in the cost of cadmium metals from December 1986 to September 1988

(Modern Plastics 1988).   Cadmium pigments exhibit brilliant shades of color,

have a high heat stability (cadmiums are considered irreplaceable in high

temperature nylon and polyester applications),  have good lightfastness,  and

are sensitive to acids (Brannon 1988).

                  b.  Lead- and Cadmium-based Heat Stabilizers  Used in PVC  and
                      Other Resins

                  Heat stabilizers are used to prevent the degradation of

resins during processing,  when molten plastic resins  are exposed to high

temperatures,  or are used to extend the life of the final  products into which

they are incorporated.   Polyvinyl chloride is especially vulnerable  to

decomposition and degradation during processing;  consequently this resin

accounts for the major share of consumption of heat stabilizers.   In addition,
                                    -  13 -

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chlorinated polyethylene and blends of ABS and PVC often require stabilization




(Plastics Engineering Handbook 1987).




      Polyvinyl chloride stabilizers prevent changes in color and performance




during processing and use, and are usually based on lead, organotin or




cadmium/barium systems.  The specific choice of heat stabilizer is determined




by the specific effect on end-products that is required.  Many formulations




are available in two forms:  liquid and solid.  Liquids (there are no liquid




lead-based stabilizers) are usually used with flexible polyvinyl chloride, and




solids, with higher metal concentrations, are used in rigid polyvinyl chloride




because it is processed at higher temperatures.  Table 4 presents some




representative lead- and cadmium-based products that are used in polyvinyl




chloride resins (Plastic Additives Handbook 1987).




                        i.  Lead-containing Heat Stabilizers




                        Lead compounds are the oldest group of stabilizers.




Among their advantages is the ability to form complexes with chlorine,




preventing the formation of free radicals that destabilize PVC.  The lead




chloride complexes that form do not have any destabilizing effect on PVC and




thus co-stabilizers such as polyols and phosphites are not required (Plastic




Engineering Handbook 1987).



      One lead stabilizer, lead stearate, has the added characteristic of




being an excellent lubricant, providing it with a second function during PVC




processing.  Lead stearate, therefore, is added to the basic lead salts to




create an excellent mixture that is compatible with all PVC types.




      Because neither  lead stabilizers nor their reaction products with




chlorine increase the  conductivity of PVC, they are used predominantly in wire




and cable insulation applications.  Lead stabilizers are the best products




available in  this area, providing good electrical properties (e.g.,





                                    - 14 -

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                                Table 4.  Representative Cadmium and Lead-based Heat Stabilizers  and Their  Properties
        Stabilizer
Concentration of
Stabiliser in FVC
      (phr)
                                                          Typical Uses
                                                          Properties and Reasons for Use
Lead Stabilizers

    Tribaslc lead sulfate       2.0-4.0
    Dibasic lead phosphite      2.0-4.0
    Dibasic lead phthallate     0.5-i.O
    Dibasic lead stearate       0.5-1.0
    Normal lead stearate        0.5-1.0
    Dibasic lead carbonate      0.5-1.5
                     e   Hire and cable insulation material
                     e   Pressure pipes and fittings
                     e   Interior and exterior sheets and profiles
                                                         Do  not require co-stabilizers or other
                                                         additives  to increase performance
                                                         Do  not increase the conductivity of FVC
                                                         articles
                                                         Good processability
                                                         Impart good mechanical properties to end
                                                         products
Cadmium Stabilizers*

Liquids

    Ba/Cd decanoate (and
    other fatty acid salts)
    Ba/Cd alkyl phenols
    Ba/Cd benzoates
Solids
    Ba/Cd decanoate
    Ba/Cd alkyl phenols
    Ba/Cd benzoates
    1.5-2.0

    1.5-2.0
    1.5-2.0
    1.5-2.5
    1.5-2.5
    1.5-2.5
   White outdoor profiles
   Furniture film
   Floor tiles
   Shoes and soles
   Hoses
e  High performance applications
Light co-stabilizing effect
Good transparency
Used in a wide range of products
Ease of handling
Excellent heat stability and self-
lubricating
                                                     e  Same  as  for  liquid  cadmium stabilizers
•OTE:  phr - parta per hundred parts of resin.

• Cadmium containing stabilizers are numerous and the properties that each  impacts to  finished products can vary significantly.

Sources:  Plastic Additives Handbook 1987,  Plastics Engineering Handbook  1987.
                                                                       -  15  -

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insulation) and the heat stability required during service  (Bedford 1989,

Plastics Additives Handbook 1987).

      Lead-based stabilizers, although effective in many other applications,

have been and continue to be eliminated from most applications.  Their use in

pressure pipes, sewage pipes, gas pipes, gutters, profiles and other

applications continues to decline because of toxicity concerns and because

economically and technically feasible substitutes are available for these

applications (Argus 1989a).   For these reasons, lead-containing PVC

stabilizers currently consumed are used almost exclusively in the electrical

cable insulation industry (Argus 1989b).  Table 5 shows some of the advantages

and disadvantages of lead heat stabilizers and Table 6 presents current and

past applications.   In 1983, expectations that the National Sanitation

Foundation would approve lead-based stabilizers for PVC in potable water pipe

promoted growth in lead stabilizers (Modern Plastics 1983),  but approval was

not granted causing a move away from use in non-potable water pipe as  well

(Bedford 1989).*

                        ii.   Cadmium-containing Heat Stabilizers

                        The  predominant cadmium heat stabilizers are actually

mixtures of barium and cadmium salts of natural straight chain fatty acids,

branched synthetic acids, and occasionally alkyl phenols and benzoic acid

derivatives.  The combination of barium and cadmium salts provides a

synergistic effect, the cadmium salts providing good color stability in
       If non-potable water pipe were  continued  to be manufactured with  lead,
while potable water pipe was made with non-lead products,  there would be
problems with cross contamination, dual inventories,  and confusion  during
installation.  As economically feasible substitutes  for lead heat stabilizers
in water and sewage pipes are available,  lead use is  expected to be  completely
eliminated from these uses (Bedford 1989).

                                    -  16  -

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      Table 5.  Advantages/Disadvantages of Lead-based Heat Stabilizers
         Advantages
          Disadvantages
   Excellent  electrical  properties

   Excellent  lubrication

   Good processability

   Inexpensive

   Wide range of forms:  oiled
   powders,  flakes and pellets to
   reduce dusting
•  Too alkaline for some
   applications

•  Cannot be used with transparent
   PVC articles

•  Certain pigments are incompatible
   with lead salts

•  Dust formation and worker
   exposure problems

•  Health and toxicity concerns
   associated with end-products
Sources:   Plastics Additive Handbook 1987,  Bedford 1989,  Kirk-Othmer 1983,
          Radian 1987,  Vinyl Institute 1989b.
                                    - 17 -

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      Table  6.   Current and Declining Uses  of Lead-based Heat  Stabilizers
            Current Uses
                                                    Declining Uses
•  Electrical cable insulation

•  Electrical conduit

•  Wire coating

•  Telephone cable insulation

•  Garden hose

•  Footwear
•  Water pipe

•  Sewage pipe

•  Gutters

•  Indoor and outdoor profiles

•  Sound records (LPs)

•  Floppy disk jackets

•  Traffic cones
Sources:  Bedford 1989,  Franklin 1990,  Kirk-Othmer  1983,  Radian  1987, Vinyl
         Institute 1989b.
                                    -  18  -

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initial processing and the barium salts providing good long-term thermal




stability during use (Chemical Additives Handbook 1987).




      Cadmium stabilizers yield cadmium chloride, which unlike lead chloride,




has a destablizing effect on PVC, necessitating the addition of deactivating




components such as polyols, phenolic antioxidants, and phosphites.  These co-




stabilizing agents further improve the performance of the barium/cadmium heat




stabilizers.



      The complex composition of barium/cadmium stabilizers requires that




special attention be paid to other components of plastic additives systems




(e.g., antioxidants, plasticizers, and fillers) so as to ensure optimum




properties.  Special attention is also necessary during processing (heating




and formulating) technique and when selecting characteristics of the end




product, thereby accounting for the wide variety of barium/cadmium




stabilizers.



      Barium/cadmium  (Ba/Cd) stabilizers can be separated into liquid and




solid formulations.   Solids in the form of powders are metal salts of fatty




acids with  phenolic antioxidants and polyols used in combination with liquid




phosphites  and  liquid epoxy plasticizers.  Formulations containing 10 percent




cadmium  or  more are used extensively in rigid PVC applications such as



pigmented profiles and sheets for  the building sector.  Powders containing




less  than 10 percent  cadmium are used in flexible PVC for shoes, hoses, and




profiles.   Powdered stabilizers  are self-lubricating, but processing




conditions  requiring  a large amount of stabilizer may result in over




 lubrication.  This problem can be  overcome by combining liquid and powdered




 Ba/Cd stabilizers  (Argus 1989b).



       Liquid stabilizers are not self-lubricating, but are easier to handle




 than solids because  they are  liquid and because  they already have phosphites





                                     -  19  -

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 mixed in.   Because of lower metal content they are sufficient only for lower




 temperature processing (i.e.,  flexible PVC only).   Often liquid Ba/Cd




 stabilizers also contain zinc  compounds that improve  early color and sulfide




 stain resistance (Vinyl Institute 1989b).   Table  7 presents the advantages and




 disadvantages  of barium-cadmium heat  stabilizers,  and Table 8 presents use



 areas for  Ba/Cd stabilizers.




       C.   Consumption of  Lead-  and Cadmium-containing Products in Plastics




       Most of  the consumption  of lead and  cadmium  in  plastics can be  broken




 down  into  the  four following areas:   lead-based pigments,  cadmium-based




 pigments,  lead-based  heat stabilizers,  and cadmium-based heat stabilizers.




 Although lead  and cadmium may be  present in  other  plastic  additives (e.g.,




 lubricants, mold release  agents,  catalysts,  or blowing agent  "kickers") or amy




 be impurities  in certain  metal-based  additives, these minor sources of  lead




 and cadmium are  not analyzed in  this  report.  The  remainder of this section



 identifies consumption by major use area.




            1-   Consumption of Lead-based Pigments




            Table  9 shows the amount of discarded lead-based pigments at



 intervals  for  the period  from 1970 until 1986.  Although the discards of




plastic resins have more than tripled over that period, the discards of lead-




based pigments have increased much more slowly.  This  difference may be due to




 increasing concern about possible health effects of lead in plastic products.




      By calculating the amount of lead in pigments lost during plastics




manufacturing  (assumed to be about 2 percent for this  analysis),  the amount of




lead that  is found in plastic products can be estimated (EPA 1989).  The resin




quantity used in calculating the lead/resin weight  ratio includes resins




containing no lead pigments  and therefore does not  reflect  a typical or
                                    -  20 -

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           Table 7.  Advantages and Disadvantages of Cadmium-based
                               Heat Stabilizers
  Stabilizer
    Type
      Advantages
        Disadvantages
Powdered Ba/Cd
•   Very good heat
    stability

•   Self-lubricating

•   Wide range of
    products

•   High metal content

•   Excellent for
    outdoor
    applications when
    combined with
    liquid phosphites
    and epoxy
    plasticizers
•  Must be combined with
   liquid phosphites and epoxy
   plasticizers

•  Sensitivity to water
   causing reversible
   cloudiness in transparent
   products

•  Dust problems
 Liquid  Ba/Cd
     Easier  to handle

     Wide  range  of
     products

     Prevents
     stabilizer  plate-
     out and dispersion
     problems

     Added light
     stability because
     of phosphites  and
     epoxy plasticizers
     -- excellent for
     outdoor
     applications
   Limited self-lubrication

   Odor that may be maintained
   in finished products

   Water sensitivity
 Sources:  Plastics Additives Handbook 1987,  Bedford 1989,  Kirk-Othmer  1983,
           Radian 1987.
                                     - 21 -

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               Table 8.   Uses for Cadmium-based Heat Stabilizers
Stabilizer Type                                 Uses


Powdered Ba/Cd       •  Extruded pigmented rigid PVC profiles

                     •  Extruded rigid sheets


Liquid Ba/Cd         •  Extruded flexible PVC profiles and articles

                     •  Injection molded sandals and shoe soles

                     •  Calendared films for furniture,  decoration, or
                        agricultural uses


Sources:  Plastics Additives Handbook 1987,  Bedford 1989,  Kirk-Othmer 1983,
          Radian 1987.
                                    -  22  -

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           Table  9.   Discards  of Lead in Pigments for Plastic in MSW
               Lead in            Total Resin Discarded
         Pigments Discarded*     in Nonfood Applications1"
Year           (tons)               (thousands of tons)        Lead/Resin Ratio
1970
1975
1980
1986
647
813
967
990
2,061
3,098
5,103
8,111
0.00031
0.00026
0.00019
0.00012
Note: The term resin refers to the type of plastic.  The resins included in
      this consumption table could include all of the resins identified in
      Table 2.

* Adjusted for net exports and with manufacturing losses estimated to be 2
percent; although  the source discusses cadmium pigments, lead-based pigments
are  found in  similar forms, and  therefore similar losses are expected  (Yost
and  Greenkorn 1984).

b Total resin figure includes resins containing no lead-based pigments.

Sources:  EPA 1989, Franklin 1990.
                                     -  23  -

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 average concentration of lead that may be found in lead containing plastic.




 It  serves,  however,  as a measure of the demand for lead-based pigments




 relative to the  demand for plastics.   As can be seen in the lead/resin weight




 ratio,  the  use of lead-based colorants has  declined significantly.




             2.   Consumption of Cadmium-based Pigments




             The  trend for cadmium in pigments discarded is  illustrated in




 Table 10.   Although  used in applications slightly  different from  those for




 lead-based  pigments,  cadmium-containing compounds  often have been replaced  by




 organic  colorants  (or sometimes by  other inorganic  compounds)  largely  because




 of health concerns.   Another  factor that may  have  contributed  to  this  decline




 has been that the  tremendous  increase  in the  price  of cadmium  as  other




 applications (e.g. nickel-cadmium batteries)  has placed additional demands  on



 the available supply  of  cadmium (Bedford 1989).




      Calculating  the weight of cadmium  found in pigments was not necessary;




 the amount  of cadmium used  in colorant manufacture was available from the U.S.




 Bureau of Mines.   However,  it was still necessary to estimate the amount of




 cadmium  lost during the manufacture of plastics.  From the net quantity of




cadmium  remaining, the cadmium/resin weight ratio was calculated.   As can be



seen in Table 10, demand for cadmium pigments (relative to resin demand) has



decreased.




            3.   Consumption of Lead-based Heat Stabilizers




            The change in demand for lead-based heat stabilizers (relative to




resin demand) has not been great over the 17 year period shown in  Table 11




 (1970 to 1986).  The discards of PVC resin have increased by  slightly  more  than




200 percent.  Unlike consumption of lead-based pigments, however,  the demand




for lead-based heat stabilizers has increased, albeit at a lower rate than the




demand for resin.  Because heat stabilizers  affect  the working  properties  of





                                    - 24 -

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        Table 10.  Discards of Cadmium in Pigments for Plastic in MSW
            Cadmium in
        Pigments  Discarded*
Year          (tons)
 Total Resin Discarded
in Nonfood Applications1"
  (thousands of tons)
Cadmium/Resin Ratio
1970
1975
1980
1986
162
256
259
259
2,061
3,098
5,013
8,111
0.000079
0.000083
0.000052
0.000032
 Note:   The term resin refers to the type of plastic.  Practically,  plastics
        are classified by the nature of the major resin(s) used in their
        manufacture.   The resins included in this consumption table could
        include all of the resins identified in Table 2.

* Adjusted for net exports and with manufacturing losses assumed to  be 6
percent (Yost and Greenkorn 1984).

b Total resin figure  includes resins containing no cadmium-based pigments.

Source:  EPA 1989.
                                     -  25  -

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           Table 11.  Discards of Lead in Stabilizers for PVC in MSW
Lead in
Stabilizers Discarded"
Year (tons)
1970 770
1975 1,284
1980 1,746
1986 2,184
Total Resin Discarded
in Nonfood Applications1"
(thousands of tons) Lead/Resin Ratio
275 0.0028
523 0.0025
624 0.0028
879 0.0025
Note:  The term resin in this table refers only to polyvinyl chloride (PVC)
       resins.


• Based on 1 percent manufacturing losses (Yost and Greenkorn 1984) .

b Total resin figure includes PVC resin containing stabilizers other  than lead
based stabilizers.

Source:  EPA 1989, Franklin 1990.
                                    -  26 -

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the resin, it is generally more difficult to find suitable replacements for

lead-based products in this application.

      Lead-based heat stabilizers are used predominantly in PVC resins.  After

accounting for lead lost during manufacturing, the amount of lead in PVC

products was estimated.  From this figure, the lead/PVC weight ratio could be

calculated.  Similar to the methodology used for pigments, the resin quantity

used to estimate the lead/resin ratio includes PVC not containing any  lead.

            4.  Consumption of Cadmium-based Heat Stabilizers

            Table 12 shows the trend in the discards  of cadmium-containing

heat stabilizers for the period 1970-1986.  From the  net quantity of cadmium,

the cadmium/resin weight ratio was calculated.  As can be seen in the  table,

unlike the lead compounds, demand for cadmium heat-stabilizers (relative to

resin demand) has decreased dramatically.  The difference in the patterns of

use  (compared to lead) may be a result  of the increase  in cadmium's price and

resultant attention to reformulating with lower cadmium content  (Argus 1989b,

Bedford  1989).*

       D.   Potential Substitutes for Lead- and Cadmium-containine Additives for
           Plastics

       The selection of a particular  lead  or  cadmium  pigment and/or heat

 stabilizer is  dependent  on processing  requirements,  resin characteristics, and

 end-product uses.   Identification of potential  substitutes  is, therefore, a

 complicated and application-specific task.   There  are,  however,  some  general

 classes of substitutes available for each cadmium and lead-based additive

 type.   The following sections describe the performance,  cost,  feasibility, and
      * Another source at Argus (unknown)  considers the 1970 data presented  in
 Table 10 to be suspect.  He characterizes lead and cadmium consumption to be
 essentially constant for more than ten years (Vinyl Institute 1989b).
                                     - 27

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         Table  12.   Discards  of Cadmium in Stabilizers  for PVC in MSW
Cadmium in
Stabilizers Discarded"
Year (tons)
1970 241
1975 280
1980 273
1986 305
Total Resin Discarded
in Nonfood Applications1*
(thousands of tons) Cadmium/Resin Ratio
275 0.00088
523 0.00054
624 0.00044
879 0.00035
Note: The term resin in this table refers only to polyvinylchloride
      (PVC) resins.

• Manufacturing losses are assumed to be 2 percent (Yost and Greenkorn 1984).

b Total  resin includes PVC resins containing stabilizers without cadmium.

Source:   EPA 1989.
                                    -  28 -

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other considerations that dictate how potential substitutes can replace




traditional lead and cadmium products.




            1.  Potential Substitute Colorants and Their Properties




            Although there is some agreement on the performance




characteristics of pigments (i.e., chemical compatibility, light and heat




fastness, hue, and intensity) which are of concern to most consumers (plastics




manufacturers), the selection of a substitute will depend in large part upon




the individual consumer's ranking of the importance of these attributes.  For




example, a manufacturer of beach balls may worry mostly about hue and




intensity and not be concerned about heat fastness.  On the other hand, a




manufacturer of high-performance automotive polymers may find a less vibrant




color acceptable if the substitute is heat-resistant and performs suitably in




the other areas.




      Particular colorant-polymer combinations may also be ruled out for a




variety of other reasons.  The first problem that might be encountered is a




chemical incompatibility between the colorant and the polymer solvent,  resin,




or manufacturing by-products.  For example, some pigments may not be used in




PVC because of their sensitivity to acid (Kirk Othmer 1983).   In addition to a




chemical resistance problem, the colorant may not be able to survive harsh




processing conditions for certain polymer resins.   For example,  although the




end use of a plastic polymer may not require high temperatures,  extensive




heating during processing is often required to melt and mold a plastic.  In




addition to these obstacles, a colorant-polymer combination may be ruled out




because of the end use of the plastic product.  A combination that is




sufficiently lightfast and suitable for indoor use may be ruled out for




exterior applications.  Table 13 provides possible substitutes and their




performance properties for lead and cadmium pigments.





                                    - 29 -

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      For purposes of this analysis, potential substitutes for lead and

cadmium pigments are chosen based only on the characteristic of having a

similar hue as reported in the Plastic Additives Handbook (1987).  Because

application-specific considerations are often critical for establishing exact

substitution patterns, lead- and cadmium-based pigments are grouped together

(i.e., substitutes are considered for the color yellow; not chrome yellow

(lead) and cadmium yellow).  A potential substitute for each major hue (red

and yellow) was chosen from the chemical families that are comprised of

inorganic and organic pigments and dyes.  In addition, two potential organic

substitutes, quinacridone and perylene pigments, were chosen based on

information from Mobay (1989) that reported they could be used with high

performance polymer systems (e.g., nylon, polyesters).

                  a.  Costs of Lead- and Cadmium-based Pigments and Their
                      Potential Substitutes

                  For most of the lead-based and cadmium-based colorants,  many

technically acceptable substitutes are available, although as mentioned above,

the costs of the substitutes may be significantly higher.   The price of

cadmium has increased as other markets, such as that for nickel-cadmium

batteries, increase the demand for cadmium.  On the other hand, lead pigments

have remained inexpensive.  Table 14 shows recent prices for the most common

lead- and cadmium-based pigments, as well as prices for some pigments (mostly

organic) that could be used as substitutes in various applications.

      According to one industry contact, as a rule of thumb,  the performance

of organic pigments increases as the price does (Hoechst-Celanese 1989).

Certain pigments may not perform as well as less expensive organics  in a few

measures of performance, but the quality must be higher in at least  one aspect

of performance or there would be no demand for the product.   For example,
                                    - 30 -

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                                      Tabla 13.  Pobantial Substitutes for Lead and Cadmium Pigments and Their Performance Properties
       Potential
  Substitute Colorant
                           Hues
              Heat
           Stability*
              CO
                  Opacity/
Lightfastnessb  Hiding  Power
 Remarks on Performance0
(Compatible Polymer/Resin)
        Possible Substitute For:d
Inorganic
  Nickel titanium
  Iron oxide
                          Yellow
                          Red
                                      300
                                      300
                                       Opaque


                                       Opaque
General suitability, but greatly
reduced tinting strength

General suitability, but only
in mixtures of dark shades
Lead chromate; cadmium sulfide;
cadmium sulfide + zinc

Lead molybdate; cadmium/sulfide selenide
H-PVC -
Organic
. Monoazo
Monoazo naphthol
Quinacridone
Perylene
Dyes
Pyrasolone derivative
Azo dye
Yellow 260
Red 280
Red 240-280
Red 220-300
Yellow 300*
Red 260*
7-8
5-7
7-8
7-8
7-8«
2-5«
Transparent LDPE, PS +; PVC -
Transparent PVC, PS, LDPE +; HOPE (+*)
Transparent PS, PVC, LDPE +; HOPE (+*)
Transparent PS, PVC, LDPE +; HOPE (+*)
Transparent PMMA, H-PVC, PS +
Transparent PMMA..H-PVC, PS +
Lead chromate;
cadmium/sulfide
Lead molybdate;
Lead molybdate;
Lead molybdate;
Lead chromate;
cadmium sulfide
Lead molybdate;
cadmium sulfide;
selenide
cadmium/sulfide selenide;
cadmium/sulfide selenide
cadmium/sulfide selenide
cadmium sulfide;
+ zinc
cadmium/sulfide selenide
• For heat stability,  the temperature is stated at which no coloristic changes occurred during normal  dwell  times  (approximately 5 minutes)  in processing machines.

D Determination of llghtfastness is carried out in accordance with DIN 53 389.   1  is the  lowest value;  *  has 8  times  the fastness level of 1;  the highest value is 8,
testing not normally being carried out beyond this level.  See Plastic Additives Handbook (1987)  for more information.
e Polymer Codes:
PS - polystyrene; LDPE - low density polyethylene;  EtWA  -  polymethyl methacrylate;  HOPE - high density polyethylene; PVC - polyvinyl chloride;
H-PVC - Unplasticized PVC.
  Polymer Performance:  + denotes sultable/recoanended;  -  limited suitability/recommended;  -  denotes  not suitable/reconnended;  () denotes a qualification of the statement;
                        * denotes caution is needed in the case of HOPE  articles  sensitive  to distortion.

* Possible substitutes were based primarily on colorant  hue as reported  in  the Plastic Additives Handbook  (1987).

• For dyes, lightfastness and heat stability depends to  an especially high  degree on the plastic to be  colored.

Source:  Brannon 1*88, Plastic Additives Handbook 1987,  Vinyl Institute 1989b.
                                                                                  -  31  -

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              Table  14.   Costs:   Lead-  and Cadmium-based Pigments
                           and Potential Substitutes
                                                           Cost
               Hue                                       ($/lb.)b
              Yellow     Lead/Cadmium Pigments
                         Lead chromate                    $ 1.55
                         Cadmium sulfide                  $14.60
                         Cadmium sulfide + zinc           $14.60

                         Substitute Colorants*
                         Nickel titanium (inorganic)      $ 3.50
                         Monoazo (organic)                $17.95
                         Pyrazolone derivative (dye)      $20.32
              Red        Lead/Cadmium Pigments

                         Lead molybdate                   $ 2.25
                         Cadmium/sulfide selenide         $18.15

                         Substitute Colorants'
                         Iron oxide (inorganic)           $ 0.79
                         Monoazo naphthol (organic)       $24.25
                         Quinacridone (organic)           $32.00
                         Perylene (organic)               $41.20
                         Azo dye (dye)                    $10.30
Note: It has not been possible to establish the exact colorant to resin ratio
      required to achieve equal coloring properties for potential substitute
      products as compared to the lead- and cadmium-containing pigments.  As a
      result, it is not possible to develop a cost per pound of resin for
      substitute products.

• The substitute colorants listed are based on having a similar hue (i.e.,  red
or yellow) as reported in the Plastic Additives Handbook (1987).  In addition
to cost, specific selection of a substitute is dependent on a diverse set of
performance properties.  For a comparison of these properties, see Table 13.

b Costs were determined by contacting chemical companies and requesting prices
on given pigments (from Plastic Additives Handbook).  The costs are based on
the most commonly used (standard) packaging sizes (40-60 Ib. containers)
reported by the chemical companies.

Sources:  BASF 1989, Bayer-Mobay 1989, Plastic Additives Handbook 1987.
                                    - 32 -

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prices generally increase as the acceptable processing temperatures rise.

This consideration, combined with the smaller production scales of specialty

and high-performance plastics help maintain the price differential.

     In addition, the amount of product used for an application is dependent

mainly on the shade and brilliance required.  For example,  if  a faint yellow

is required, less lead chromate is used than would be required for a darker

yellow.  In general, for similar hues, 25 percent less organic pigment by

volume is required compared to an inorganic pigment  (Hoechst-Celanese 1989).

Estimates are not available as to the amount of dye required for  coloring.

               b.  Other Factors Affecting Selection of Substitutes and
                   Substitute Costs

               If lead and cadmium pigments were not available, chemical

companies may be more willing to invest in the research and development of

substitutes, because there would be  less  low-cost competition  for any new

substitutes developed.   From Table  13,  it is evident that  there are many

substitutes available  for  lead and  cadmium pigments; however,  it  may be

 impossible  to  find  exact replacements  for some pigments  (such  as  some of the

very high-  performance  cadmiums used in nylons) at  any cost.   In  those cases,

 it may be  necessary for  the plastic manufacturer  to sacrifice  one aspect of

 performance,  such  as hue or brilliance,  in  exchange for  another,  such as heat

 or lightfastness.

      Several  of the companies  contacted (Harshaw  1989, Heubach 1989) are still

 committed to  the manufacturing and/or distribution  of  lead-based  pigments, but

 the majority of the companies  contacted have  ceased to  supply  them.  The same

 cannot be said for some of the cadmium-containing colorants; their performance

 characteristics are more difficult to reproduce  using  either organic or other

 inorganic pigments.  Although there are organic  pigments  which match cadmium
                                     - 33 -

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 pigments in brilliance, hue, and lightfastness, they generally are not




 adequate in high-temperature situations.  On the other hand, although many of




 the inorganic compounds are quite heat resistant,  they are tinctorially weak



 or colorless (white).




      The toxicity of heavy metals is well known,  and therefore many




 manufacturers have shied away from using compounds containing metals such as




 lead and cadmium.   For example,  General Electric  stopped using lead pigments




 approximately 10 years ago and ceased use of cadmium pigments at  the beginning



 of 1989  (General Electric 1989).




      Research by many  other manufacturers continues  in  order to find potential




 substitutes  for  lead and cadmium  compounds  that are  compatible with  high-




 performance  engineering resins such  as  polycarbonate, nylon,  and  other




 polyesters  (Modern Plastics  1987).   Combinations of  substances are sometime*




 used  to  complement each other and improve the overall qualities of products.




 For example,  in  an application requiring  some hiding power and resistance to




 heat, a  mix  of a high  performance organic colorant and an inorganic compound




 may work.  The inorganic pigment lends  its hiding power while the organic




 provides intense color.  In some instances the inorganic compound may also




 provide  some color,  thereby reducing the need for large quantities of organic




 colorant, which would be required if the inorganic pigment were colorless



 (white)  like titanium dioxide.




     Although dyes can often be used in place of pigments, they currently do




not hold a large share of the market for colorants.   Because  dyes  must be




 soluble  in the resins they are used in,  each variety of  dye may be compatible




with only a few types of resins.   In addition,  the  lead-  and  cadmium-based




pigments are generally applied in a solid form,  either as color concentrates




or dry powders.  Although dyes are also found in solid form,  they  are  usually
                                    -  34 -

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used as liquids which would require some changes in the plant equipment and




result in additional costs to the plastic manufacturer.



          2.  Potential Substitute Stabilizers and Their Properties




          Potential substitute products that could replace lead- and cadmium-




containing heat stabilizer products have been developed and continue to be




investigated for several reasons.  The toxicity of lead and cadmium compounds,




the availability of an increasing number of technically superior alternate




products, the lower costs of substitutes, and increasing costs  associated with




using  lead and especially cadmium products have all been influencing factors.




This section addresses potential substitute products,  compares  costs to




existing  lead and  cadmium products when possible, and  discusses important




factors that affect substitution.



     The  majority  of  lead-based heat  stabilizers have  been replaced in




applications where substitution  is  technically and/or  economically feasible.




For  example, organotin  stabilizers  (e.g., alkyltin mercaptides,  alkyltin




carboxylates,  and  estertin  mercaptides), barium/zinc,  and metal-free




 stabilizers can be used in  rigid applications, pipes and fittings, pigmented




 profiles, foamed profiles,  and phonograph records  that previously used lead-




 based products (Argus 1989c).   Table  15  identifies  PVC articles and stabilizer




 systems that can replace lead-based products  in  rigid  PVC  applications




 (Plastics Additives Handbook 1987).



      Lead stabilizers also have been  used in flexible  PVC  applications.  These




 applications can be split into those  for which cost-effective and reliable




 substitutes have been developed (shoes,  sandals,  and soles),  and those for




 which substitution has lagged (electrical insulation and jacketing).




 Electrical insulation applications appear to use the majority of lead-based
                                     - 35 -

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       Table 15.  Potential Substitutes' for Lead-based Heat Stabilizers
                             in Rigid PVC Products
                            Methyl, Butyl                       Metal-
                           and/or Octyltin      Butyltin         Free
      PVC Item              Mercaptides         Esters       Stabilizers


Pipes and Fittings               X

Pigmented Sheets and
Profiles                         X                X

Foamed Profiles                  X

Phonograph Records                                               X


• Ba/Cd stabilizers are not considered to be substitutes for lead stabilizers
due to toxicity considerations and the scope of this analysis (i.e., lead and
cadmium products are both under investigation and therefore are not considered
to be substitutes for one another),  although they may be technically and
economically feasible in some applications.

b Phonograph records may be stabilized with  certain metal-free stabilizers.

Source:  Plastics Additives Handbook 1987.
                                    -  36  -

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stabilizers because of the critical non-conducting nature of lead products

(Vinyl Institute 1989a).

      The use of electrical cable insulation and jacketing can be divided

among three major use areas:

            •     power wiring,
            •     telephone cable, and
            •     cords and connectors for appliances and
                  other consumer items.

The critical properties of weathering, humidity resistance, and thickness of

the jacket in the power wiring and telephone cable applications have made

substitution difficult given  that lead imparts these properties.  Lead heat

stabilizers for these applications provide outstanding use characteristics and

there currently are no products available on the market  that can replace the*e

lead-based products  (BF Goodrich 1989).

      The power and  telephone cable uses account for about 50 percent of lead

stabilizer usage  for jacketing and insulation, while the cord/connector

applications account for  the  remaining 50 percent.  It is believed  that these

lower performance cord/connector applications  can be replaced with  alternate

stabilizers  (Argus  1989c,  BF  Goodrich 1989).   The reformulated products were,

however,  too experimental or  could not be  identified at  this time.

      Teflon* is  a technically feasible substitute for PVC coatings, but is

not a one-for-one substitute  in  that  heat  stabilizers  are not replaced, but

 rather  reformulation is  required (i.e.,  Teflon* replaces PVC not lead).  The

 use of  Teflon* has not been examined  by the industry as  a viable replacement

 for cable insulation and is expected to  be  on  the order  of  five  to  ten times

 more expensive (Bedford Chemical 1989).   Teflon* also may not possess

 sufficient flexibility for many applications  (Vinyl Institute  1989b).
                                     - 37 -

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   Table 16.  Potential Substitutes' for Lead-based Heat Stabilizers
                        in Flexible  PVC  Products
                                        Ba/Zn      Butyltin
      PVC Item                       Stabilizers    Esters
Cable Insulation and
Jacketingb

Shoes, Sandals,
Soles
  Note:  Ba - barium; Zn - Zinc

  ' Barium/cadmium stabilizers are not considered to be substitutes
  for lead stabilizers due to toxicity considerations and the scope
  of this analysis (i.e., lead and cadmium products are both under
  investigation and therefore, are not considered to be substitutes
  for one another),  although they may be technically and
  economically feasible in some applications.

  b Teflon* is a technically feasible substitute for PVC coatings,
  but is not a one-for-one substitute in that  heat stabilizers are
  not replaced,  but rather reformulation is required (i.e.,  Teflon*
  replaces PVC not lead).  The use of Teflon*  has  not been examined
  by the industry as a viable replacement for  cable insulation and
  is expected to be on the order of five to ten times more expensive
  (Bedford Chemical 1989).  Teflon* also  may not possess sufficient
  flexibility for many applications (Vinyl Institute 1989b).
  Sources:   Argus 1989c,  Bedford 1989,  Plastic  Additives  Handbook 1987.
                                -  38  -

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Table 16 identifies the potential substitutes for lead-based stabilizers used

in flexible PVC applications.

      Barium/Cadmium heat stabilizers have a wide range of applicability in

rigid and flexible PVC applications.  The products and potential substitutes

are identified in Tables 17 and 18.  There is some overlap with lead-based

stabilizers, but these are not considered to be substitutes for cadmium-

containing products and vice-versa.  The processing techniques (e.g.,

calendaring, extrusion, injection molding, blow molding, pressing, coating),

the processing conditions (temperature, mixing, alkalinity) and a host of

other reasons, including the presence of other additives, the end use of the

product  (indoor/outdoor), and the costs of potential substitutes, influence

which products are ultimately considered to be substitutes.  In general, thete

are adequate substitutes for cadmium-containing stabilizers, including

barium/zinc, calcium/zinc, and tin-based stabilizers.

                  a.  Costs of Lead- and Cadmium-based Heat Stabilizers and
                      Potential Substitutes

                  Lead and cadmium heat stabilizers have seen widespread use

because  of  their relatively low cost compared to newer substitute products.

As concern  has mounted regarding the toxicity of lead and cadmium products,

substitute  products have been perfected and costs of substitutes have declined

 (Argus  1989b).  Table 19 presents the relative costs of lead, cadmium,

 substitute  products.

       It must be noted that the actual substitution pattern for lead and

 cadmium stabilizers is very complicated.  The wide range of applications,

 processing  considerations, and other factors that affect potential substitute

 development and entry  into the market make it difficult to distinguish exact
                                     -  39  -

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              Table 17.  Potential Substitutes" for Cadmium-based
                    Heat Stabilizers in Rigid  PVC  Products
                                                          Barium/
                                  Butyltin    Butyltin     Zinc
           PVC Item              Mercaptides   Esters     Solids
Films for Non-food Applications      X                       X

Pigmented Profiles
      - - Indoor                      X                       X
      - - Outdoor                                 X           X

Foamed Profiles                      X                       X
• Lead stabilizers are not considered to be  substitutes  for  Ba/Cd
stabilizers due to toxicity considerations and the scope of this analysis
(i.e., lead and cadmium products are both under investigation and therefore,
are not considered to be substitutes for one another),  although they may be
economically and technically feasible in some applications.

Source:  Plastic Additives Handbook 1987.

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              Table  18.   Potential Substitutes*  for Cadmium-based
                  Heat  Stabilizers in Flexible  PVC Products
                                Butyltin         Barium/        Calcium/
                               Mercaptides        Zinc            Zinc
      PVC Item                  or Esters      Stabilizers     Stabilizers
Films for Non-food
Applications                       X                 XX

Profiles and Flexible
Tubes for Non-food
Applications                                         X               X

Shoes, Sandals and
Soles                                                x

Artificial Leather
Coatings                                             x               X

Dippings                                             X               X
 a Lead stabilizers are not considered to be substitutes for Ba/Cd
 stabilizers  due  to toxicity  considerations  and the  scope  of this analysis
 (i.e.,  lead  and  cadmium  products  are both under investigation  and  therefore,
 are  not  considered to be substitutes for one  another),  although they may be
 economically and technically feasible  in some applications.  The relative
 amount  of cadmium in liquid  stabilizers can be reduced  by the  addition of zinc
 fatty acid salts that replace the corresponding cadmium salts  (Modern Plastics
 1987).

 Source:   Plastic Additives Handbook 1987, Vinyl Institute 1989b.
                                       41 -

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Table 19.  Costs of Lead, Cadmium, and Potential Substitute Heat Stabilizers
Stabilizer Class
Lead
Lead compounds
Organotin stabilizers
Barium/zinc stabilizers
Teflon*
Cadmium
Barium/cadmium liquids
Barium/cadmium solids
Barium/cadmium/zinc products
Zinc/calcium products
Liquid organotin stabilizers
Solid organotin stabilizers
Barium/zinc liquids
Barium/zinc solids
Approximate
Cost Range
0.50-1.00
1.00-3.00
2.00-4.00
a
0.95-1.75
1.85-2.75
0.95-1.70
1.00-3.00
3.00-4.50
8.00-10.00
1.25-2.50
2.00-4.00
Amount Used Per
Hundred Parts of Resin
1.0-3.0
1.5-2.5
1.5-3.0
Not Applicable
1.0-4.0
1.5-3.0
1.0-3.0
1.0-3.0
2.0-4.0
1.5-3.0
1.0-4.0
1.5-3.0
  • Teflon* is a different class of substitute in that it would replace the
  end product,  PVC coatings,  used for wire and cable  insulation.   It is not
  currently considered a stable substitute for economic  reasons.   The cost of
  PVC coatings  is  roughly $0.50 to $1.00/lb.  and for  Teflon* >$5/lb.

  Sources:   Argus  1989a,  1989b, 1989c;  Bedford 1989.

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substitution patterns.  The costs presented in Table 19 should be considered,

therefore, rough approximations.

                  b.  Other Factors Affecting Selection of Substitutes and
                      Substitute Costs

                  There are a number of considerations that must be included

in the selection of stabilizer substitutes and estimation of costs for

comparison to costs for lead and cadmium stabilizers.  It has not been

possible  to characterize each of these considerations, but they are provided

for completeness:

      •     Potential substitute stabilizer packages that can replace lead or
            cadmium products may be required in quantities greater or lesse'r
            than the products they replace.  They may be cheaper or more
            expensive, at  the concentration level required, or they may be
            viable only for some applications.

      •     The addition of co-stabilizing* products may reduce potential
            substitute costs, improve performance to a level above that of the
            lead or cadmium product, or increase product service life.

      •     It may be possible  to combine  stabilizers so that a synergistic
            effect  is achieved,  thereby improving performance and/or reducing
            costs.

      •     New potential  substitutes are  constantly being developed and made
            available.  Some  of these, based on antimony and metal-free
            stabilizer  systems  (e.g., diphenylthioureas, and S-
            aminocrotonates)  have not been widely accepted, but may influence
            the  stabilizer market over the next few years.
      * Co-stabilizers are usually organic compounds  that enhance  the  solvency
 of stabilizers or provide some other benefit, but are not stabilizers if used
 alone.
                                       43 -

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       E.   References

Argus.   1989a (May 10).   M.  Croce.   New York,  NY.   Transcribed telephone
conversation with Mark Wagner,  ICF  Incorporated,  Fairfax,  VA.

Argus.   1989b (May 11).   D.  Stimpfl.   New York, NY.   Transcribed telephone
conversation with Mark Wagner,  ICF  Incorporated,  Fairfax,  VA.

Argus.   1989c (May 17).   D.  Brilliant.   New York, NY.   Transcribed telephone
conversation with Mark Wagner,  ICF  Incorporated,  Fairfax,  VA,

BASF.  1989  (May  16).  Basic Organics  Group.   Transcribed  telephone
conversation with Tanya Yudleman, ICF  Incorporated, Fairfax, VA.

Bayer-Mobay  Corporation.   1989  (May 16).   Transcribed  telephone  conversation
with Tanya Yudleman, ICF  Incorporated,  Fairfax, VA.

Bedford Chemical.   1989 (May 4).  D. Gauw.  Bedford Chemical,  Division  of
Ferro Corporation.   Bedford, OH.  Transcribed  telephone conversation with  Mark
Wagner, ICF  Incorporated,  Fairfax,  VA.

Brannon, SM.   1988  (February 1-5).  43rd Annual Conference, Composites
Institute, the Society of  the Plastics  Industry.  Colorants for Composites  --
A Review.

EPA. 1989  (January).  U.S. Environmental Protection Agency.  Characterization
of Products  Containing Lead  and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Franklin Associates.  1990 (August).  Characterization of Lead in Plastic
Products in Municipal Solid Waste,  1970 to 2000.  Prairie Village, KS.

General Electric  Color Lab.  D.  Bryant.  1989 (May 4).  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated,  Fairfax,  VA.

B.F. Goodrich.  1989 (May 17).   G. Lefebvre.   Cleveland, OH.   Transcribed
telephone conversation with Mark Wagner, ICF Incorporated,  Fairfax, VA.

Harshaw Colors.   1989 (May 12).   M.  DiLorenzo.   Division of Eagelhard Corp.
Transcribed telephone conversation with Don Yee, ICF Incorporated,  Fairfax,
VA.

Heubach,  Inc.  1989  (May 12).  Transcribed telephone conversation with  Don
Yee, ICF Incorporated,  Fairfax,  VA.

Hoechst-Celanese.   1989 (May 9).  D. Wave.   Transcribed telephone conversation
with Don Yee, ICF Incorporated,  Fairfax, VA.

Kirk-Othmer.   1983.  Encyclopedia of Chemical  Technology.   John Wiley and Sons
Publishing Co., Inc.  Vol. 18,  pp. 184-206; Vol.  14, pp.  168-183;  Vol.  6.

Mobay.   1989 (May 3).  J.  Graff.  Transcribed  telephone conversation with Don
Yee, ICF Incorporated,  Fairfax,  VA.


                                    - 44 -

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Modern Plastics.  1982 (July).  McGraw-Hill Publishing Co., p. 44.

Modern Plastics.  1983 (September).  Chemicals and Additives Special Report.
McGraw-Hill Publishing Co.

Modern Plastics.  1985 (September).  Chemicals and Additives Special Report.
Colorants -- pp. 60-62; Heat Stabilizers -- pp. 68-69.  McGraw-Hill Publishing
Co.

Modern Plastics.  1987 (September).  Colorants -- pp. 68-71; Heat Stabilizers
--pp. 70-71.  McGraw-Hill Publishing Co.

Modern Plastics.  1988 (September).  Chemicals and Additives Special Report.
McGraw-Hill Publishing Co.

Modern Plastics.  1989 (January).  Resin Report.  McGraw-Hill Publishing Co.

Plastics Engineering Handbook.   1987.  4th Edition.  Van Nostrand Reinhold
Publishing Company.

Plastic Additives Handbook.  1987.  Hanser .Publishers.  Munich, Germany.
            t
Radian.  1987.  Chemical Additives for the Plastics Industry.  Radian
Corporation.  Noyes Data Corporation.  Park Ridge, NJ.

Vinyl Institute.  1989a (May 15).  R. Gottesman.  Little Falls, NJ.
Transcribed telephone conversation with Mark Wagner, ICF Incorporated,
Fairfax, VA.

Vinyl Institute.  1989b (July 11).  R. Gottesman.  Comments received on the
Draft Plastics Section.

Yost, K. and K. Greenkom.  1984 (January).  Source Specific Impacts and
Exposure Mechanisms for Cadmium.  Purdue University.
                                    - 45 -

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III.
      A.  Overview of the Pigment Industry
      A pigment can be defined as a substance that imparts color to other
materials.  Depending on the size of the pigment particles, different
wavelengths of light can be selectively absorbed thereby producing a desired
color.  Pigments are normally insoluble in the medium that they are dispersed.
Pigments are often chosen for incorporation into a final product based on
tinctorial strength, brightness, texture, durability, and cost.  Pigments are
usually classified as being inorganic or organic.  Organic pigments by
definition contain carbon.
      B.  Uses of Lead- and Cadmium-containing Pigments
                                                                  t
      Pigments are used in a wide variety of products: in paints and inks; atf
to color plastics, paper, rubber, and glass.  Although the use of lead- and
cadmium-containing pigments in plastics is representative of their use in the
other use areas discussed in the EPA 1989 report, certain properties such as
heat resistance may be more important in other use areas such as glass and
ceramics.  For a discussion of the uses of lead- and cadmium-containing
pigments refer to Chapter II on plastics.
      C.  Consumption of Lead and Ca^ium in Pirments
      Lead and cadmium-containing pigments are used in plastic, glass/ceramic,
and rubber products that are disposed in municipal solid waste facilities.
The consumption of lead and cadmium in pigments is discussed in Section C of
Chapter II on plastics, Chapter VI on glass, and Chapter XI on rubber.   The
tables are repeated here for ease of reference.
      D.  Potential Substitutes of Lead- and Cadmium-containing P^jp^nts
      The potential substitutes for lead- and cadmium-containing pignwnts are
discussed in Section D of the Plastics Chapter (Chapter II).   The potential

                                    - 46 -

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          Table 20.  Discards of Lead in Pigments for Plastic  in MSW
               Lead in            Total Resin Discarded
         Pigments Discarded*     in Nonfood Applications1*
Year           (tons)               (thousands of tons)        Lead/Resin Ratio
1970
1975
1980
1986
647
813
967
990
2,061
3,098
5,103
8,111
0.00034
0.00026
0.00019
0.00012
Note: The term resin refers to the type of plastic.  Practically, plastics are
      classified by the nature of the major resin(s) used in their
      manufacture.  The resins included in this consumption table could
      include all of the resins identified in Table 2.

• Adjusted for net exports and with manufacturing losses estimated to be 2
percent; although the source discusses cadmium pigments, lead based pigments
are found in similar forms, and therefore similar losses are expected (Yost
and Greenkorn 1984).

b Total resin figure includes resins containing no lead-based pigments.

Source:  EPA 1989.
                                    - 47 -

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 Table  21.   Discards  of Lead  in Pigments  in Rubber  Products  in MSW
          Discards of         Discards of          Total Discards
            Lead in        Lead in Fabricated        of Lead in
         Tire Pigments      Rubber Products       Rubber Pigments'
Year        (tons)               (tons)                (tons)
1970
1975
1980
1986
45
44
83
56
16
15
33
21
52
53
104
70
• Ten to fifteen percent of tires and other rubber products are
diverted or recovered annually.

Source:  EPA 1989.
                              - 48 -

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        Table 22.  Discards of Lead in Pigments in
           Ink and Miscellaneous  Products  in MSW
Year
 Discards of
   Lead in
Ink Pigments*
   (tons)
 Discards of
 Lead in All
    Other
Miscellaneous
  Pigments'5
   (tons)
                                              Total Discards
                                              of Lead in Ink
                                             and Miscellaneous
                                                 Pigments
                                                   (tons)
1970
1975
1980
1986
19,192
13,819
8,222
265
7,828
3,198
1,642
866
27,020
17,017
9,864
1,131
  Note: Total consumption includes only pigments
        other than those found in plastics,
        rubber, glass, and ceramic glazes.

  a Based on net consumption of lead in inks, assuming 5
  percent manufacturing losses and adjusted  to exclude
  inks  in recycled papers.

  b Includes pigments in textiles, adhesives, artists'
  paints, and miscellaneous applications.

  Source:   EPA  1989.
                           -  49 -

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         Table 23.  Discards of Cadmium  in  Pigments  in  Plastic  in MSW
            Cadmium in         Total Resin Discarded
        Pigments Discarded"   in Nonfood Applications11
 Year          (tons)            (thousands of tons)
Cadmium/Resin Ratio
1970
1975
1980
1986
162
256
259
259
2,061
3,098
5,013
8,111
0.000079
0.000083
0.000052
0.000032
Note: The term resin refers to the type of plastic.  Practically,
      plastics are classified by the nature of the major resin(s) used
      in their manufacture.  The resins included in this consumption
      table could include all of the resins identified in Table 2.

a Adjusted for net exports and with manufacturing losses assumed to be 6
percent (Yost and Greenkorn 1984).

b Total resin figure includes resins containing no cadmium-based pigments,

Source:  EPA-1989.
                                    - 50 -

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  Table 24.  Discards of Cadmium in Pigments for Glass, Ceramics, and
                      Miscellaneous Products in MSW
Year
      Cadmium
   Discarded in
   Pigments for
Glass and Ceramics'
      (tons)
   Cadmium Discarded
    in Pigments for
Miscellaneous Products'5
         (tons)
 Total Discards of
Cadmium in Pigments
for Glass, Ceramics
 and Miscellaneous
     Products0
      (tons)
1970
1975
1980
1986
32
27
23
29
79
65
56
70
111
92
79
99
a Half of the glass and ceramics with cadmium pigments are assumed to
end up in MSW.  Discards are assumed to be in the year of manufacture
for the glass product.

b Includes pigments in products other than plastics, rubbers, and
glass/ceramics.  Products are assumed to be discarded in the year of
manufacture.

c Includes pigments other than those found in rubbers and plastics.

Source:  EPA 1989.
                                  -  51  -

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Table 25.  Discards of Cadmium in Pigments
        for Rubber Products in MSW
               Cadmium in Pigments
               for Rubber-Products*
      Year            (tons)
      1970              10

      1975              13

      1980               8

      1986               6
      * Consumption of cadmium pig-
      ments in rubber was assumed to
      be one percent of total con-
      sumption of cadmium pigments.

      Source:  EPA 1989.
                  - 52 -

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substitutes for these pigments used in glass/ceramic* and rubber products are

assumed to be similar to those discussed in the plastics chapter.

      E.  References

EPA. 1989 (January).  U.S. Environmental Protection Agency.  Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Yost, K. and K. Greenkorn.  1984  (January).   Source Specific Impacts  and
Exposure Mechanisms  for Cadmium.   Purdue University.
      * Pigments are used in glazes and enamels.  Glazes and enamels are
  discussed  in the glass/ceramic chapter (Chapter VI).  The consumption of lead
  pigments used  in glass products is not available.  The EPA 1989 report
  identifies lead consumption  in glass only at the aggregated level.  The
  proportion of  this  total lead use that is attributable to lead pigments is.
  therefore,  not available.
                                      -  53  -

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 IV.   SOLDER

       A.   Overview of the Soldering Industry

       Solder is  used in a variety of products  to form both electrical and

 structural bonds between various  types  of materials.*  The most common use  of

 solder is  to attach electrical  components to printed circuit  boards  (Arconium

 1989).  The soldering process is  useful  in that  it  allows  manufacturers  to

 easily automate  the simultaneous  attachment of multiple components.   The major

 markets for these  printed circuit boards  are in  computers, communication

 devices, and government/military  uses.   It should be noted that the products

 discussed  in this  chapter are those  that  are disposed  of in municipal solid-

 waste  (MSW)  and  therefore, may  exclude certain applications.  For example,

 solder  is  used in  the manufacture of automobile bodies and automobile  parts

 that are assumed to be disposed in other  types of waste facilities (EPA  1989J.

      The  soldering process is  defined as  a  metallurgical joining method using

 a filler metal (the solder) with a melting point below 600°F (316*C).

 Soldering  relies on wetting** for  the bond formation and does  not require

 diffusion* with base metals to  achieve bonding  (Manko 1979).   The  limit of

 600*F was  set arbitrarily; many people consider 800'F (427°C)  the  upper
        Both electrical and structural bonds join parts physically.  Unlike an
electrical bond, however, a structural  bond is not  required to transmit
electricity.

         "Wetting" describes the relationship between molten solder and the
surfaces of materials that are being soldered.   Solder with good wetting
ability forms intimate continuous  contact with the  materials to be  soldered.

        In the  context of bonding,  "diffusion" means the joining of parts by
melting them together.  Under  certain chemical conditions,  the materials  in
soldered parts  can also diffuse into each other  without being heated.

                                    . 54 .

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temperature limit for soldering.*  Soft solders are characterized by melting

temperatures below 375eF, while hard solders melt between 375T and 800*F

(Manko 1979, Belser 1954).

            1.  Solder Characteristics

            Solder is available in a wide variety of compositions and forms,

but is almost always an alloy composed of two  to six types of metal.**  While

tin and lead are the most common elements found in solder, solder alloys can

also include indium, bismuth, cadmium, antimony, silver, gold, zinc, copper,

mercury, gallium, germanium, aluminum, arsenic, and silicon. (Indium 1988,

Manko 1979, Alpha Metals 1989, Warwick 1985).  The most common type of  solder

used in consumer electronics, however, is tin/lead solder (Kapp 1989).

      B.  Solder Use Areas

      While solder is used  in a wide variety of military, industrial, and

commercial products, this report addresses only the use of solder in consumer

(commercial) products that  are disposed of in  MSW facilities.  Three solder

use areas in consumer products have been identified:  consumer electronics,

light bulbs, and cans (for  food and non-food products).

            1.  Consumer Electronics

            Consumer electronics disposed of in MSW facilities include

products  such as televisions, radios, and video cassette recorders.  This

report  assumes  that all  of  the solder found in consumer electronics is  used  to
      * The upper  temperature limit of soldering separates soldering operations
 from brazing operations.   While  both bonding operations  rely on a filler
 metal, brazing is done at a temperature  level sufficient to partially melt the
 base metals  to help form the bond.

      **  Most solder alloys contain only two or three types of metal (Indium
 Corporation  of America 1988).

                                     -  55 -

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make electrical bonds in printed circuit boards in these electronic devices.*

In 1986, consumer electronics accounted for 11.7 percent of the printed

circuit market (EPA 1989).

      Although home computers are a popular type of solder-containing consumer

product, the printed circuit boards found in home computers are not usually

disposed of in MSW.  Instead, these circuit boards are removed for repair and

returned to manufacturers for recovery of components such as memory chips (EPA

1989).  Therefore, this report assumes the home computer circuit boards become

industrial waste rather than MSW.  This report also assumes consumer

communications equipment (e.g.,  telephones) enters industrial waste rather

than MSW (EPA 1989).

      The chief reason tin/lead solder is used to produce consumer electronics

is cost (Talco 1989).  Because specialty solders employ more exotic metals,

the tin/lead alloy can be many times cheaper than a substitute solder.

Tin/lead solder also has advantageous physical properties --it has good

wicking tendencies;** has  some pliancy  to resist breakage from vibration,

bonds aggressively at a relatively low temperature,  which avoids the

possibility of thermally shocking the parts to be soldered;  and it has  good

electrical continuity (IPC 1989b, Sylvania 1989a).   Tin/lead solder also works

well in the manufacture of solder clad printed circuit boards (printed  circuit

board manufacturing is discussed below).

      Cadmiua-containing solder is not commonly used to manufacture consumer

electronics.  Manufacturers avoid the use of cadmium because of health-related
     * This assumption is based on the methodology found in EPA  1989  report.

     ** The "wicking"  ability  of solder is its tendency  to produce strong
bonds by travelling up the holes used to mount components on some printed
circuit boards.

                                    - 56 -

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concerns including the generation of poisonous fumes during the soldering

operation (IPC 1989b, Keeler 1987, Indium 1989d).

                  a.  Through-hole and Surface Mount Printed Circuit Boards

                  Two technologies can be used to attach electrical components

to printed circuit boards  -- through-hole assembly technology or surface mount

assembly technology.  With surface mount technology  (SMT), components are

attached directly to the board without drilling  or punching holes  (see  Figure

1).  Without holes, components can be densely packed on the board  thereby

reducing the size of the board.  Texas Instruments cites a 40 percent

reduction in size of the printed circuit board assembly over through-hole

technology when  surface mount technology is used (Mullen 1984).

      With through-hole technology,  the leads of the electrical components  are

placed  into holes that have been drilled in the  circuit board  (see Figure 1);

Usually the circuit board  is soldered on the side of the board from which the

 leads protrude (IPC  1989c).

                  b.   Printed Circuit Board Manufacturing

                  There are  several  methods used to  manufacture the circuit

 board to which components  are attached.  The oldest  technique  is called

 "subtractive"  and can be  used to  make either single- or double-sided circuit

 boards.* The  process begins with a  copper clad  circuit board in its initial

 state -- a laminate such  as  fiberglass  or  epoxy that has been  coated with

 copper on on* or both sides.  A protective pattern of  "etch  resist" is

 deposited on the copper surface,  and the unwanted copper  is  etched away (hence

 the name "subtractive").   The  subtractive  process can  be  further categorized

 according to the type of etch resist used (Manko 1986).
      * A single-sided board can accept components on only one  side, while a
 double-sided board can accept components on both sides.
                                     - 57

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                      i) DIP Through-hole Component.
                ii) SMC J-lead Surface-Mount Component.
Figure 1.   Comparison of Through-Hole and Surface Mount  Technologies
(Source:   Mullen 1984.)
                                    -  58

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      The most common subtractive method used to produce double-sided and




multilayer boards employs tin/lead plating as the etch resist.  The first step




involves coating the board with organic resist in a negative image of the




circuit pattern.  Next, tin/lead is applied with an electroplating process to




create a positive image of the circuit pattern.  The organic resist and the




copper are then stripped, leaving a copper circuit pattern protected by the




tin/lead plating (Manko 1986, IPC 1989c).  This method of circuit board




production can be used for through-hole and surface mount assemblies.




      The advantage of tin/lead plating is that it protects the copper from




oxidizing, allowing the circuit board to be stored for long periods (IPC




1989b).  The use of tin/lead clad circuit boards encourages the use of




tin/lead solder during assembly of the printed circuit board because the




solder blends with the alloy already plated on the circuit board.  The use of




a  different solder alloy, while possible, can lead to problems as the




resulting solder alloy will be an unknown and possibly weak or low-melting




composition.  Unfortunately, most of the desirable alloys for soldering are




not suitable  for electroplating, making their use more difficult (Manko 1986).




       Circuit boards  may  also be manufactured with a "print and etch" or an




 "additive" process resulting  in printed circuit boards with bare copper that




needs to be protected from oxidation.  Organic coatings  can be applied over




 the copper  to provide good protection  for several months, but this oxidation




protection method  does not last as long as a tin/lead coating that can protect




boards from  oxidation for periods of 2-3 years  (IPC 1989b).




             2.   Cans  for  Consumer Uses



             Cans may  be  categorized as one of  two types  -- a two piece can or




 a three piece can.  A two piece can consists of  two pieces --a cup-shaped




 bottom and a top.   The bottom of  a two piece can is seamless and the top is





                                     -  59  -

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always attached by crimping without the use of solder.  A  three piece  can

consists of three pieces  -- a top, bottom, and the cylindrical middle  piece.

Three piece cans have a seam down the side that must be sealed (CMI 1989b).

      Cans used in consumer applications can be grouped into three major

categories:  food, beverage, and non-food (general packaging) cans.  Non-food

cans are used primarily for aerosol products (CMI 1989a).*  Virtually all

beverage cans are two piece cans that do not require solder for manufacturing.

Some food and non-food cans, however,  do contain solder to seal the can
seams.
      The small number of food cans that are currently manufactured with

solder employ solder that does not contain lead (with the possible exception

of cans containing dry foods such as coffee that will not leach lead into the

product).  Some imported food cans, however, may contain lead solder (NFPA

1989b).   Non-food cans (such as those used for aerosols) may also use lead-

containing solder (CMI 1989a, NFPA 1989a).

      Lead solder is used in cans because of its low cost and because its low

melting temperature makes it easy to work with.   Cadmium-containing solder is

not used in the manufacture of cans (CMI 1989b).

            3.  Light Bulbs

            Consumer light bulbs can be grouped into two major categories--

incandescent and fluorescent.  Solder is used only in the manufacture of

incandescent bulbs.  Tin/lead solder is used in one of the final steps in the

manufacture of incandescent bulbs when the  ends  of the filament wire that
        Aerosol products account for approximately  two thirds of non-food
cans.  Other non-food cans include paint,  varnish,  and automotive  product  cans
(CMI 1989a).

        Only 3  percent of  all food cans contain solder (CMI 1989b).

                                    - 60 -

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protrude from the threaded end of  the bulb are  soldered  to  the  small  metal  tab

at the base of the light bulb.  Soldering not only prevents  the filament wire

from snapping off during use, it also enhances  the ability of the  filament  to

make good contact in the light socket (Sylvania 1989a).

      Tin/lead solder is used to manufacture light bulbs for several  reasons.

It is a low cost solder and melts  at a relatively low  temperature.  The low

melting temperature of tin/lead solder is critical in  light bulb manufacturing

as soldering is a final operation  that could destroy the quality of the bulb

if the bulb glass is allowed to heat up to the  point where it will release  C02

and water into the light bulb assembly.  Tin/lead solder also works fast and

bonds parts together aggressively  (Sylvania. 1989a).

      C.  Consumption of Lead and  Cadmium in Solder

      Lead is used in solder for the manufacture of consumer electronics,

cans, and light bulbs.  Although specialty solders that do not contain lead

can be used to manufacture these items,  lead-containing solders dominate the

solder market (Talco 1989).

            1.  Consumption of Lead in Solder

            Eutectic* tin/lead alloy (63  percent tin/37 percent  lead)  is  the

most common soldering alloy currently in use (Kapp 1989).  Almost all the lead

used to solder consumer electronics, cans,  and light bulbs is contained in

tin/lead solder (Sylvania 1989a,  Talco 1989,  CMI 1989b).   The amount of lead

used to manufacture and subsequently discarded in MSV for each of these items
       A eutectic solder is an alloy of a certain composition such  that  it
melts at the lowest temperature of any alloy containing the metals  involved.
This allows the alloy to melt at a specific temperature.   Most alloys melt
over a temperature range and have a "mushy" state between the solid and  liquid
states.

                                    - 61 -

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is presented in Table 26.  All of the lead consumption presented in this table

is attributable to the use of lead-containing solder (EPA 1989).

                  a.  Consumer Electronics

                  The amount of lead consumed in consumer electronics has

increased steadily from 1970 to 1986.  Consumer electronics were the fourth

largest contributor of lead in MSW in 1970, but by 1975 they were the second

largest contributor, a position they continue to hold (EPA 1989).  The Bureau

of Mines, however, reports a general decline in the use of lead in solder in

electronic devices.  Discards of lead in printed circuit boards found in

consumer electronics are projected to decline to less than 1,000 tons and less

than 1 percent of total discards by 2000 (EPA 1989).   Because virtually no

cadmium is consumed in solder in the manufacture of consumer electronics,

cadmium-containing solder is not treated in this discussion (IPC 1989b).

                  b.  Cans for Consumer Uses*

                  Solder is used in the manufacture of three piece cans to

form bonds along the seams.   Due to consumer law suits and pressure from the

Food and Drug Administration, however, the use of lead-containing solder to

manufacture cans used for food and beverage products  has declined

significantly over the past ten years (CMI 1989a).   Lead-containing solder is

still used to manufacture non-food containers and some cans for dried food

(such as coffee) that cannot leach lead, but this application accounts for a

small amount (approximately 3 percent) of total can production (NFPA 1989a,

CMI 1989b).  The sharp decline in the use of lead-containing solder to

manufacture food cans is reflected in Table 26, as  indicated by discard
     * Cadmium-containing solder is not used in the manufacture  of cans
 (Elkins 1989).

                                    - 62 -

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                 Table  26.  Discards  of Lead  in  Solder  in MSW
       Discards of Lead                              Discards  of      Total
        in Solder from      Discards of Lead  in        Lead  in      Discards
          Containers            Solder from          Solder  from     of  Lead  in
       and Metal Cans'     Consumer Electronics1"     Light Bulbs0     Solder
Year        (tons)                 (tons)               (tons)         (tons)
1970
1975
1980
1986
24,117
20,122
9,675
2,052
1,417
1,759
3,441
6,092
156
161
197
225
25,690
22,042
13,313
8,369
* Metal cans are assumed to be discarded in the year of manufacture.
Containers are assumed to last 3 years.  All cans are assumed to go into MSW,
but only 20 percent of containers.  Adjustments were made for recycling, which
constituted 2, 3, 5, and 4 percent of all discards in 1970, 1975, 1980, and
1985 respectively.  These assumptions and adjustments reflect the methodology
found in the EPA 1989 report.

b Consumer electronics are assumed to have a product life of 8 years.   This
category includes the circuit boards and chassis of electronic equipment.

0 Light bulbs are assumed to be discarded one year after manufacture.
Although some newer bulbs have longer lifespans, discards of solder from light
bulbs increased due to the continued use of shorter lifespan bulbs employed
for cost reasons and because of the increased number of incandescent lamps in
use (Roach 1989).

Source:  EPA 1989.
                                    - 63 -

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figures for lead-containing solder that have dropped by a factor of 12 between




1970 and 1986.




                  c.  Light Bulbs




                  Light bulbs are not a large source of lead solder in MSW,




but are of interest because they contain two sources of lead -- solder and




leaded glass.   The discards of lead in light bulbs shown in Table 26 addresses




only lead solder.  Because the manufacture of fluorescent bulbs does not




require solder, the consumption figures address only the manufacture of




incandescent bulbs (EPA 1989).




      Although lead-containing solder consumption in light bulbs has not risen




as fast as consumption in consumer electronics, 1986 consumption is about 40




percent higher than 1970 consumption.  In the past, cadmium solder was used in




the manufacture of light bulbs.  Virtually all bulbs made today, however,




contain tin/lead solder.  Solder used in light bulb manufacturing contains




about 70 to 80 percent lead to keep solder costs down.   Lead is relatively




cheap and the metallurgy of the solder in this application is not critical




(Indium 1989e).  Cadmium-containing solders are no longer used to make light




bulbs (Sylvania 1989a).




                  d.  Plumbing Solder




                  Until recently, tin/lead solder was the most commonly used




alloy for soldering plumbing.  Recent legislation promulgated under the Safe




Drinking Water Act Amendments of 1986, however, prohibits the use of lead-




containing solder to bond pipes for plumbing in public potable water systems




if the solder contains more than 0.2 percent lead (42 U.S.C. 300f).   States




were required to enforce this law as of June 19, 1988.   The substitute solders




that dominate the plumbing solder market are 95 tin/5 antimony solder alloy,




and silver-containing solder  (2 to 3 percent silver) for use on ferrous base





                                     - 64 -

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metals (PDI 1989, NAPHCC 1989).  It is important to note, however, that the




majority of plumbing solder would not be expected to be disposed of in MSW.




            2.  Consumption of Cadmium in Solder




            While cadmium occasionally may be used in specialty solders,  it  is




a toxic compound that can emit poisonous fumes during the soldering process




and is, therefore, not used in consumer applications disposed at MSW.  The use




of solders containing cadmium demands a controlled process under a hood




(Keeler 1987).  Although light bulbs were once manufactured with a cadmium-




containing solder, virtually all bulbs are currently manufactured with




tin/lead solder  (Sylvania 1989a).  Cans and  consumer electronics also do  not




contain cadmium  solder  (NFPA 1989a, IPC 1989c).




       D.  Potential  Substitutes  for Lead- and  Cadmium-containing Solders




       Potential  substitutes for  lead-containing  solders may be broken into two




groups -- substitute solders and substitute  processes.  Depending on the




soldering process used,  some alternative solders may be used as drop-in




substitutes,  and others  may require redesign of  soldering equipment or other




processing  equipment.   Substitute  processes  usually eliminate the use of  lead-




containing  solder by eliminating the need for  solder during manufacturing.




 For example,  can manufacturers may eliminate solder use by substituting a




welding process  that requires  no solder.  The  availability and cost of




potential  substitutes for each of  the  market areas  identified is discussed in




 the remainder of this section.   Consumer  electronics manufacturers will




 continue to use lead-based solders,  as will  manufacturers of light bulbs.




 Lead-containing solders used in can manufacturing have  for the most part  been




 eliminated through the use of substitute  processes  (CMI  1989a).  Because  the




 use of cadmium in consumer electronics,  cans,  and  light bulbs is rare,




 substitutes for cadmium-containing solders  are not  discussed.





                                     -  65  -

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             !•   Substitutes  for  Lead-containing  Solder  in  Consumer  Electronics




             Although many  types  of  solder may  substitute for  tin/lead solder




used  in the  manufacture of printed  circuit boards in consumer electronics,




none  of the  substitutes have exactly the same  characteristics as  tin/lead




solder.  The use of a substitute solder usually  changes the soldering




characteristics of melting temperature, required flux type, ability to wet the




surfaces to be soldered, and bond strength.  Depending on  the substitute




solder and the particular  application for which  it is used, the soldering




characteristics may be enhanced or diminished.    The advantages and




disadvantages of the common specialty alloy families are presented in Table



27.




      The trend of the printed circuit board industry toward surface mounted




components will probably increase the use of indium and bismuth alloys due to




their low melting point and superior thermal fatigue resistance to slow-cycle




fatigue.   These qualities are important for manufacturing surface  mounted




circuit boards because of the stresses  induced  by the  small size of  the bonds




and the large coefficients of thermal expansion (Manko  1988, Keeler  1987).




      Other alloy families may also  be  used for soldering surface  mounted




components.   The choice of solder depends  primarily  on  the  material




compatibility with components,  melting  temperature,  strength,  and  cost (IPC




1989c, Alpha Metals 1989).   Because  the variety of custom compositions is




extensive,  it is not possible to  describe  the soldering  characteristics of all




alternative solders.   Instead,  some  of  the  most important general  attributes




of each alternative solder family are discussed below.
                                    -  66  -

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             Table 27.  Advantages and Disadvantages of Potential
            Substitute Solders  for Consumer Electronic  Applications
Solder Alloy Family
Advantages
Disadvantages
Bismuth/Tin
Tin/Silver
Indium/Tin
Indium/Silver
   Well-suited to the
   new surface mount
   assembly technology
•  Can be used to
   solder silver-
   plated base metal
   without
   significantly
   solubilizing the
   silver

•  Well suited to the
   new surface mount
   assembly technology

•  Compatible with
   gold and other
   precious metals
   Well suited to the
   new surface mount
   assembly technology

   Compatible with
   gold and other
   precious metals
•  May have
   unacceptably low
   melting
   temperatures for
   use in consumer
   electronics
   applications

•  Higher cost than
   tin/lead solder

•  Less ductile than
   indium and bismuth
   solder alloys

•  Higher cost than
   tin/lead solder
   Low melting point
   may not be suitable
   for high
   temperature
   applications

   As much as 20 times
   the cost of
   tin/lead solder

   Low melting point
   may be not suitable
   for high
   temperature
   applications

   As much as 20 times
   the cost of
   tin/lead solder
 Sources:  ADL 1990, IPC 1989c, Manko 1979, Keeler 1987, Indium 1989e.
                                    - 67 -

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                   a.   Indium Alloys




                   Indium  alloys  are  one  of  the most  important  potential




substitutes  for  tin/lead  solder  used in  printed circuit board  manufacturing.




Unlike tin,  indium is  compatible with gold  and other precious  metals  (Keeler




1987).  Most indium alloy solder is  used to solder gold or gold-plated  parts




(Indium 1989b).  Also, indium alloys  do  not require radically  different




soldering temperatures; in comparison to the tin/lead alloy family, many




indium alloys melt  at  a lower or equivalent temperature (see Figure 2).




      The low melting  temperature of  indium alloys not only reduces thermal




shock to electrical components,  it also  imparts ductility to a solder joint so




it will not crack  (Keeler 1987).  Mismatched coefficients of expansion between




the circuit board and  the electrical  components can create serious stress




problems (especially with surface mount  technology) (Manko 1986).  The




ductility of indium solders not  only  relieves this thermal stress, it also




helps the solder bonds to withstand excessive vibration (Keeler 1987).  On the




other hand,  the high operating temperature of many consumer products combined




with this low melting  temperature may make indium solder unsuitable for some



applications (ADL 1990).




                  b.  Bismuth Alloys




                  Bismuth alloys melt from 300"F down to 100*F -- well below




the boiling point of water (Manko 1979).   Extremely low temperature solders




are not used in consumer electronics because such products may endure  high




heat levels during use (Kapp 1989,  Indium 1989e).   Bismuth alloys with




relatively high melting temperatures, however,  can be used with success  (Manko




1979,  IPC 1989c).  Because all bismuth alloys  melt at a relatively low




temperature compared to other soldering alloys  (see Figure 2),  bismuth solder
                                    -  68 -

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         9S CADMIUM
         5 SILVER
                         LEAD- I
                         SILVER I
                         ALLOYS!
                                                   Hard
                                                   Solder
CADMIUM-ZINC ALLOYS
                                                         INDIUM-
                                                         BASE
                                                         ALLOYS
                BISMUTH-
                BASE
                ALLOYS
                                                    Soft
                                                    Solder
Figure 2.   Melting Temperatures of Common Soldering Alloys (*F)
            (Adapted from Menko 1979.)
                                      -  69

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 can be  used to  rework or repair solder joints  without melting surrounding




 solder  bonds.   Bismuth also  tends  to  improve the wetting  ability of solder



 (Manko  1979).




                   c.   Tin/Silver Allovs




                   Because  tin/lead solder can  easily  dissolve  silver off a




part during soldering due  to the solubility of silver in  tin,  alternative




solder  alloys are  useful for soldering silver-plated  electrical  contacts.




While the use of alloys containing little tin  seems to be a logical  solution,




such alloys  generally melt at high temperatures and have poor  wetting




characteristics.   Because  the solubility of silver in tin increases with  an




increase in  temperature, one might  try a low melting alloy.  With the




exception of the very low  temperature bismuth alloys,  however, most low




temperature  solder alloys are rich  in tin.   Therefore, the most satisfactory




solution to  soldering  silver-plated parts is to use solder that already




contains silver to decrease the solubility of the silver plating in the tin




component of the solder.  Tin/silver alloys  are a good alternative for




soldering silver-plated electrical contacts.   This  type of alloy generally




contains little silver due to the expense of silver (Manko 1979).




                  d.   Other Considerations




                  The soldering method used  has a bearing  on the  type of alloy




a manufacturer can use.  Wave soldering machines  must  use  eutectic or near-




eutectic solders (Berke 1989a).   Most  wave soldering machines  can be adjusted




to use substitute solders of eutectic  or near-eutectic composition.   The




majority of printed circuit boards  manufactured today  are  wave  soldered




(Indium 1989d).




      An increasing number of circuit  boards employ surface mount technology.




In this process, printed circuit boards are manufactured through  the  use of a





                                    -  70  -

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reflow soldering process.  This process requires solder paste/cream  (lead-

containing or non-lead-containing solders can be employed) that does not need

to be a eutectic composition.  Approximately 30 percent of the printed circuit

boards manufactured today employ surface mount assembly technology (IPC

1989c).

      The suitability of a soldering alloy for a particular application must

be determined on a case-by-case basis.  Although history of other applications
                                                               »
can be used as a guideline,  there are no scientific rules to predetermine  the

wetting ability of solder on the materials to be soldered (Manko 1979).

                  e.  Cost of Substitute Solders

                  The main determinant of solder cost  is the cost of the

metals that compose the  solder.  The cost of the metals used in the  consumer-

electronics substitute solder alloy families listed in Table 27 are  as

follows:

            •     indium     $180/lb.
            •     silver     $89/lb.
            •     bismuth     $6.40/lb.
            •     tin         $4.10/lb.

Even  a small difference  in price between solders can have a large impact on

the consumer when a large purchase  is made  (Indium 1989e).  The cost for the

metals used  in  the eutectic  compositions of the solder alloy families listed

in Table  27  are as follows:

             •     52  indium/48  tin        $96.05/lb.
             •     97  indium/3 silver      $177.28/lb.
             •     58 bismuth/42 tin      $5.85/lb.
             •     96.5  tin/3.5  silver     $8.04/lb.

Because  of the  expense  of  indium solders, they are not commonly used (Indium

 1989e).   The main reason for the use  of  indium solder  is to bond precious

metal contacts  such  as  gold (unlike tin,  indium will not solubilize  precious

 metals)  (Indium 1989b).   Bismuth/tin and tin/silver alloys are commonly used


                                     -  71 -

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for electronics, but many variations  in  the component metals  and their




compositions may be used to solder consumer electronics depending on the




particular application.  The solder compositions discussed here  should serve




only as an initial guide to determining  suitable substitutes  for lead-




containing solder used in consumer electronics.




      While solder prices depend primarily on the cost of the constituent




metals, the solder form* also  has a bearing on cost.   Simple solder forms,




such as ingots, are relatively cheap to produce compared to specialized forms




such as solder tubing.  The manufacturing cost for ingots is approximately




$4.00 per pound (Federated 1989b).   Because the ease that a solder may be




formed depends on its composition,  the price of different types of solder is




not proportional across the range of available forms (Indium 1989c).  In




general, however,  the cost of bismuth/tin and tin/silver alloys is




approximately the same as the  cost of tin/lead alloys,  while indium alloys




cost up to 20 times as much as tin/lead alloys (Talco 1989,  Indium 1989e).




Eutectic tin/lead alloy (the commonly used composition of 63 percent tin and




37 percent lead) costs $3.75 per pound in ingot form (Talco  1989).




            2.   Potential Substitutes for Lead-containing Solder in Cans




            Soldering is a metallurgical  bonding process in  which metallic




continuity from one metal to another is established.   Brazing and welding,  two



other common metallurgical joining  processes,  can also  create  metallic




continuity between metals.   Although these substitute processes  are not




appropriate joining methods for the printed circuit board  applications where




the majority of solder is used,  welding is commonly used in  the  manufacture of




cans (CMI 1989a).   The crimping and drawing process also accounts for a large
       Some  common solder  forms are wire, paste, and ingot.




                                    -  72  -

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portion of can manufacturing.  The common substitutes used to eliminate




tin/lead solder in cans (see Table 28) are discussed below.




                  a.  Welding and Brazing




                  Welding is defined as a metallurgical joining process that




relies on the diffusion of the base metals with or without filler metal for




joint formation (Manko 1979).  Welding is the most commonly used substitute




process for soldering (NFPA 1989c).



      The welding process requires the use of copper electrodes to produce




smooth seams with no impurities.  Both the welding and soldering processes are




used to produce three piece cans  (CMI 1989a).




                  b.  Drawing and Crimping



                  As explained previously in this chapter, cans may be




categorized as two piece or three piece cans.  Virtually all beverage cans are




now two piece cans, although beverages were  packaged in soldered three piece




cans in the past  (CMI 1989a).



      The  technology used to produce all two piece cans is drawing and




crimping.  This process entails  drawing sheet metal into a cup shape, and then




attaching  a metal  lid on top of  the cup by squeezing a folded seam between the




cup and lid.  Beverage cans  constitute the majority of cans produced in the




U.S.  (CMI  1989a,  1989b).



                   c.  Substitute Solders



                   Some  food  and  non-food products are still produced in




 solder-containing three piece  cans, but almost no solder used in domestic can
                                     - 73 -

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        Table 28.
Advantages and Disadvantages of Substitute Processes
and Solders for Consumer Can Applications
Process or Solder
         Advantages
                                                        Disadvantages
Crimping


Welding


Tin Solder
            Eliminates the need
            for solder

            Eliminates the need
            for solder

            Eliminates the
            possibility of lead
            leaching into
            canned food
            products*

            May be used in non-
            food cans
•  None identified

•  None identified
                                                        •  Tin solder is more
                                                           expensive than
                                                           tin/lead solder
Note: The costs associated with crimping and welding of cans are comparable to
      the costs associated with soldering.

• Domestic soldered food cans for dried food such as  coffee  may contain lead
in the solder.  Dried food, however,  does not leach the solder into the food
product.  Some imported food cans for foods packed in juice  (such as
grapefruit sections) may employ lead-containing solder.

Sources:  Karmal 1989a, 1989b; Elkins 1989b.
                                    -  74 -

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manufacturing contains lead  (NFPA 1989b, CMI 1989b).*  Some dry food products

such as coffee may still be  packaged in cans soldered with relatively cheap

lead solder because there is no danger of lead leaching  into the  food product.

Imported food cans also may  contain lead solder.  The substitute  solder used

by domestic manufacturers is plain tin solder (NFPA  1989b).  The  quality  of

the joints produced with tin solder is equal to  those produced with  tin/lead

solder, but pure  tin solder  is more expensive than tin/lead solder  (NFPA

1989b).

            3.  Potential  Substitutes  for  Lead-containing Solder  in Light
                Bulbs

            Lead/tin solder  is used in light bulb manufacturing because it is

low cost, works  fast,  and bonds materials aggressively.   Some substitute

materials, however, are available  (see Table 29).

       Relatively expensive  indium  solder  could be used  instead of lead/tin

solder,  but  it  tends to oxidize easily during the light bulb soldering

process.   (The  final step  is to heat  the  solder  with torch flame  so  that  the

 solder will  spread over  the base  of  the bulb.)   Oxidation of indium  solder

 could be prevented by  flowing nitrogen  over the  molten  solder  (to displace the

 oxygen in the air) or  by  soldering in a vacuum.   Both measures will  increase

 the cost of the soldering process.   Tin/zinc solder  could also be used, but  it

 needs to be tested for this application (Sylvania 1989a).  Tin/zinc  solder

 does not flow as well  as tin/lead solder  (Kapp  1989).
      * Approximately 3 percent of food cans for dried food contain lead alloy
 solders.  No beverage cans contain lead alloy solders.  Although data is not
 available for general packaging cans, this type of can represented only 5
 percent of total can manufacturing in 1988 (food and beverage cans represented
 95 percent) (CMI 1989a).
                                       75

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             Table 29.  Advantages and Disadvantages of Potential
                 Substitute Solders  for  Light Bulb  Applications
Substitute Solder           Advantages     '             Disadvantages


Indium-Based Solder         •  Does not contain         •  More expensive than
                               lead                        tin/lead solder

                                                        •  Oxidizes when used
                                                           in the light bulb
                                                           manufacturing
                                                           process

Tin/Zinc                    •  Does not contain         •  Does not flow as
                               lead                        well as tin/lead
                                                           solder


Sources:  Sylvania 1989a,  1989b;  Kapp 1989.
                                    - 76 -

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            4.  Future Trends and Developments




            Conductive adhesives are a potential future substitute for




tin/lead solder used in electrical applications such as consumer electronics




and light bulbs.  The use of conductive adhesives would eliminate the need for




fluxing and post-soldering flux cleaning (Locktite 1989b).  However, several




problems currently prohibit the widespread use of conductive adhesives.




      Most conductive adhesives are silver-filled to achieve the desired level




of conductivity.  Even though conductive adhesives usually consist of more




than 50 percent silver (compared to only a few percent silver contained in




tin/silver solder),  they still do not conduct as well as solders (Locktite




1989a, 1989b).  Furthermore, the high silver content means the price of




conductive adhesives is high relative to solders (Locktite 1989b).   The high*




cost may be somewhat mitigated by the elimination of flux and flux cleaning




costs.




      Conductive adhesives are currently used in some instances where the




surface of a part may not be conductive to solder bonding or where  solder may




be too brittle for the application (Locktite 1989b).   The wholesale




replacement of tin/lead solder with conductive adhesives,  however,  is not




currently considered a realistic option (IPC 1989c).




      Some research is also being done on conductive polymers.   This potential




substitute is in early development stages and little information is available




regarding performance (Locktite 1989b).
                                    - 77 -

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      E.  References

ADL.  1990 (November 15)  Lead Use and Substitutes.  Report to Lead Industries
Association.  Prepared by Arthur D. Little, Inc., Cambridge, MA.

Arconium.  Undated.  Arconium, 400 Harris Avenue, Providence, RI.  "Arconium
Specialty Alloys."

Arconium.  1989 (July 24).  J. Hamilton, Sales Representative.  Providence,
RI.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated,
Fairfax, VA.

Alpha Metals.  1989 (July 14).  S. Arora.  Senior Chemist.  Jersey City, NJ.
Transcribed telephone conversation with Thomas Hok, ICF Incorporated, Fairfax,
VA.

Bannos, T.S.  1988 (October).  "Lead-Free Solder to Meet New Safe Drinking
Water Regulations."  Welding Journal. Vol. 67, pp. 23-26.

Belser, R.B.  1954.  "Indium -- A Versatile Solder to Metals and Non-metals,"
found in Intermediate Indallov Solders, published by the Indium Corporation of
America, Utica, NY.

CMI. 1989a (June 1).  Can Manufacturers Institute.  D. Karmal, Counsel.
Washington, DC.  Transcribed telephone conversation with Thomas R. Hok, ICF
Incorporated, Fairfax, VA.

CMI. 1989b (July 28).  Can Manufacturers Institute.  D. Karmal, Counsel.
Washington, DC.  Transcribed telephone conversation with Thomas R. Hok, ICF
Incorporated, Fairfax, VA.

EPA.  1989 (January).  U.S. Environmental Protection Agency.  Characteristics
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates, LTD.  Prairie Village, KS.

Federated-Fry Metals. 1989a (July 20).  W. Hockenberry.  Sales.  Altoona,  PA.
Transcribed telephone conversation with Thomas Hok, ICF Incorporated,  Fairfax,
VA.

Federated-Fry Metals. 1989b (August 15).  W. Hockenberry.  Sales.  Altoona,
PA.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated,
Fairfax, VA.

FPMSA.  1989 (July 28).  Food Processing Machinery and Supplies Association.
L. Herbert.  Executive Vice President.  Alexandria, VA.  Transcribed telephone
conversation with Thomas Hok, ICF Incorporated, Fairfax, VA.

Hollis Automation.  1989a  (July 18).  E. Berke.  Marketing Services
Supervisor.  Nashua, NH.  Transcribed telephone conversation with Thomas R.
Hok, ICF Incorporated, Fairfax, VA.
                                    - 78 -

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Hollis Automation.  1989b (July 28).  E. Berke.  Marketing Services
Supervisor.  Nashua, NH.  Transcribed telephone conversation with Thomas R.
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1988.  Indium Corporation of America, 1676
Lincoln Avenue, Utica, NY.  "Indalloy* Specialty Solders & Alloys."

Indium Corporation of America.  1989a (July 19).  M. DeMarco, Sales
Representative, Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1989b (July 19).  R. Altieri. Applications and
Engineering.  Utica, NY.  Transcribed telephone conversation with Thomas Hok,
ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1989c (July 20).  M. DeMarco, Sales
Representative, Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America.  1989d (July 28).  R. Altieri.  Applications
and Engineering.  Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Indium Corporation of America. 1989e (August 15).  J. Ferriter.  Application*
and Engineering.  Utica, NY.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

IPC.  1989a (May 31).  Institute of Printed Circuits.  D. Bergman.  Chicago/
IL.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated,
Fairfax, VA.

IPC.  1989b (July 20).  Institute of Printed Circuits.  D. Bergman.  Chicago,
IL.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated,
Fairfax, VA.

IPC.  1989c (July 28).  Institute of Printed Circuits.  D. Bergman.  Chicago,
IL.  Transcribed telephone conversation with Thomas Hok, ICF Incorporated,
Fairfax, VA.

Kapp Alloy and Wire, Inc. 1989 (July 19).  D. Porter, Technical Director.
Altoona, PA.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Keeler, R.  1987 (July).  "Specialty Solders Outshine Tin/Lead in Problem
Areas."  Electronic Packaging and Production, pp. 45-47.

Locktite Corporation.  1989a (May 31).  R. Thompson.  Newington, CT.
Transcribed telephone conversation with Thomas Hok, ICF Incorporated,  Fairfax,
VA.

Locktite Corporation.  1989a (July 28).  J. Jesowski.  Commercial Development
Specialist, Newington, CT.  Transcribed telephone conversation Thomas Hok,  ICF
Incorporated, Fairfax, VA.

                                    - 79 -

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Manko, H.H.  1979.  Solders and Soldering.  Published by McGraw-Hill Book
Company, New York, NY.  Second edition.

Manko, H.H.  1986.  Soldering Handbook for Printed Circuits and Surface
Mounting.  Published by Van Nostrand Reinhold Company, New York, NY.

Mullen, J.  1984.  "How to Use Surface Mount Technology."  Texas Instruments
Publishing Center, Dallas, TX.

NAPHCC. 1989 (August 10).  National Association of Plumbing-Heating-Cooling
Contractors,  R. Warren, Technical Director.  Falls Church, VA.  Transcribed
telephone conversation with Thomas  Hok, ICF Incorporated, Fairfax, VA.

NFPA.  1989a (June 1).  National Food Processors Association.  E. Elkins.
Washington, DC.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

NFPA.  1989b (July 31).  National Food Processors Association.  E. Elkins.
Washington, DC.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

NFPA.  1989c (August 15).  National Food Processors Association.  E. Elkins.
Washington, DC.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

PDI.  1989 (August 10).  Plumbing and Drainage Institute.  S. Baker, Executive
Secretary.  Indianapolis, IN.  Transcribed telephone conversation with Thomas
Hok, ICF Incorporated, Fairfax, VA.

Sylvania and Laxman, Limited.  1989a (July 18).  R. Marlor, Manager, Glass and
Ceramics.  Salem, MA.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Sylvania and Laxman, Limited.  1989b (July 28).  R. Marlor, Manager, Glass and
Ceramics.  Salem, MA.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated, Fairfax, VA.

Sylvania and Laxman, Limited.  1989c (August 30).  W. Roach.  Engineer,
Fluorescent Bulb Plant.  Danvers, MA.  Transcribed telephone conversation with
Louis Gardner,  ICF Incorporated, Fairfax, VA.

Talco Metals.   1989  (July 18).  C. Carabello,  Sales Representative.
Philadelphia, PA.  Transcribed telephone conversation with Thomas R. Hok, ICF
Incorporated, Fairfax, VA.

Warwick, M.E.   1985  (Spring).  "The Wetting and Mechanical Properties of Lead-
free Capillary  Plumbing Solders."  Brazing and Soldering. No. 8.
                                     - 80 -

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V.  LEAD-ACID BATTERIES

      Lead-acid batteries are currently the most commonly used type of

rechargeable battery.  These batteries are used for starting, ignition, and

lighting in virtually all motorized vehicles, and are used  in other

applications where rechargeable portable power is desired (e.g., consumer

electronics such as power tools).  The drawback of lead-acid batteries  is the

emission of lead and sulfuric acid when these batteries are disposed.   Lead-

acid batteries continue to be widely used because based on performance, cost,

and toxicity of potential alternatives, there are currently no acceptable

substitutes.  The discussion presented below outlines the disadvantages of the

potential substitutes that have been considered*.

      Nickel-zinc batteries have  a lower power density** than lead-acid

batteries, a limited lifetime  (50 to 200 recharging cycles), and relatively

poor reliability.  Nickel-zinc batteries are two to three times the cost of an

equivalent sized lead-acid battery (Palmer 1988).

      The power density of nickel-iron batteries is only one fourth to  one

third that of  lead-acid batteries, and they have very poor  low temperature

performance and charge retention (Palmer 1988).

      Silver-zinc batteries are  very expensive  -- 20 to 100 times  the cost of

an equivalent  sized  lead-acid battery.  These batteries also have  a limited
      *  Nickel-cadmium batteries are not considered as substitutes because of
 the scope of this study but even  they do  not match  lead-acid batteries  in
 performance.  Nickel cadmium batteries are five  to  ten  times the cost of an
 equivalent sized lead-acid battery.   The  power density  of nickel-batteries is
 20 to 30 percent lower  than lead-acid batteries  so  that the  cost of delivered
 power per unit cost is  6.67 to 13.33  times more  expensive, assuming equal
 service lives (Palmer 1988).

      ** The  power density of a battery is  the amount of power the battery can
 produce relative to its weight.

                                     - 81  -

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lifetime  (approximately 250 cycles) and decreased performance at  low

temperatures  (Palmer 1988).

      Even future advance  secondary battery systems are not promising.  Zinc-

chlorine batteries involve the danger of chlorine leakage and require complex

plumbing and  refrigeration.  Zinc-bromine batteries present safety problems

when used for automobile ignition applications, and are also bulky.  Aqueous

redox flow cells are only being considered for power storage or standby power,

while conductive polymer batteries have low power density and very poor

performance at temperature extremes.  Secondary metal-air batteries have low

energy density and may be unstable.  Finally,  lithium metal-sulfide and

sodium-sulfur high temperature systems require a high operating temperature

and are not suited for power cranking (Palmer 1988).



Reference

Palmer, J.G.   1988 (September).   Executive Vice President,  Pacific-Dunlop-GNB,
Incorporated,  St. Paul, MN.  "A Cleaner Environment:   Removing the Barriers to
Lead-Acid Battery Recycling."   Written in collaboration with M.L.  Sappington,
P.E., President,  Lake Engineering,  Incorporated,  Atlanta,  GA.
                                    -  82  -

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VI.  NICKEL-CADMIUM BATTERIES




      A.  Overview of the Battery Industry



      Secondary (rechargeable) battery systems are based primarily on  the same




chemical principles used in the construction of primary (one charge)




batteries.  The latter are sometimes called "fuel" cells, because the  active




chemicals are consumed in an irreversible reaction.  Both types of cells are




based on the difference in electrochemical potential between the anode and




cathode of the cell, which are generally metal plates.  This potential is the




driving force that provides the energy to force electrons through the  load.




When the difference in potential between the anode and cathode is reduced




sufficiently, there is insufficient energy to overcome the  resistance  of the




load, and the battery ceases to function.  With primary cells, the battery




must be discarded at this point, because the electrochemical reaction  cannot




be reversed sufficiently to derive a reasonable performance after charging




 (Kirk-Othmer 1978).



      The main difference between a primary and secondary cell is in the




nature  of the active substances; a secondary battery may be recharged  because




 it is based on a highly reversible reaction.  This allows the battery  to be




 discharged and then recharged multiple times.  A  discharge  and charge  bring




 the battery back to its original state, and this  pair of actions is called a




 cycle.  The active  substances  in a primary battery cannot be recharged.




      However, even after  charging secondary batteries, the materials  do not




 return  exactly to  their previous  (charged) state, and therefore, a secondary




 battery may be put  through only a  limited number  of cycles. Eventually the




 battery's efficiency  deteriorates  (measured by  the battery's output during




 discharge relative  to  the  energy  input during charging) and may drop to an
                                     -  83 -

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unacceptable level, or the battery may fail to charge altogether  (Kirk-Othmer




1978, Moli Energy 1989).




      The most common type of secondary battery currently in use  is  the  lead-




acid battery, which is used for starting and ignition in virtually all




motorized vehicles.  Sealed lead acid batteries are also quite common and are




found in home security and emergency power systems, as well as in consumer




electronics (VCR's, home computers, camcorders), power tools, toys,  and  other




applications where portable power is desired.




      B.  Nickel-cadmium Batteries




      Another type of secondary battery which finds widespread use in consumer




applications is the rechargeable nickel-cadmium (Ni-Cd) battery.   It is  found




in many of the same applications as the sealed lead-acid battery and may be




used in many applications for which the lead-acid is too large.   In addition,




Ni-Cd batteries are also frequently substituted for primary batteries,  in




applications such as personal tape players,  where frequent use and high




discharge rates can result in unacceptably high battery costs.




      Ni-Cd batteries are often integrated into an appliance or  toy with a




dedicated charger.  In such cases,  the battery often cannot be removed by the




user and cannot be changed except at an authorized service center for the




product.  Because Ni-Cd batteries may last for over 1000 cycles  in some




instances, the battery may outlast the useful life of the product.  Such




applications (cordless hand vacuums,  electric shavers,  power tools,  etc.)




constitute a large segment of the demand for Ni-Cd batteries.




      The other major consumer application of nickel-cadmium batteries  is as a




substitute for primary batteries such as the common carbon-zinc battery and




the alkaline battery.   As mentioned before,  Ni-Cd batteries  are most  cost-




effective in applications which consume large amounts of power, such  as





                                    - 84 -

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portable stereos and photographic strobes, rather  than  for  applications  such

as electric quartz clocks, which generally require only a single  alkaline  cell

each year.

      As the popularity of laptop computers, portable video equipment,

cellular phones, and other portable electronic devices  increases,  the demand

for rechargeable power sources also will  increase.  Given Ni-Cd batteries'

long cycle life (on the order of 1000 charge-discharge  cycles versus 200 for

sealed lead acid batteries), moderately high charge capacity,* availability

in many popular sizes, low cost  (roughly  ten times the  cost of carbon-zinc

batteries, but with more  than 100 times the lifetime of carbon-zinc

batteries), and resistance to abuse (overcharge  and deep discharge) make them

ideal for  consumer applications.

      The  only drawback to Ni-Cd cells is concern  about the toxicity of  the

cadmium in the batteries, which  eventually ends  up in the waste stream.

Sealed lead-acid batteries,  although currently commonly available, would not

be  an acceptable alternative, because of  similar concerns over lead in the

waste stream.  Fortunately however, there are other battery systems which,

although  currently not suitable  for consumer applications,  may eventually be

developed sufficiently for such  uses.  These battery systems are  discussed

below  in  Section D.

       C.   Consumption of  Cadmium in Nickel-cadmium Batteries

       The amount of  cadmium  discarded  in  Ni-Cd batteries is presented in Table

 30.  As  the  table  indicates, there has been an  increase in  total  cadmium

 discards  by  a factor of  18  in the period  1970 to 1986.  This is due in
      * Charge  capacity is  defined as  the  maximum  charge  that a battery will
 hold.  The charge capacity decreases as the number of cycles  through which the
 battery has passed increases (Moli Energy 1989).
                                     - 85

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      Table 30.   Discards of Cadmium in Nickel-cadmium Batteries in MSW
        Cadmium in Discards of     Cadmium in Discards of     Total Cadmium
       Batteries in First Year"   Batteries in Fourth Yearb     Discarded
Year            (tons)                     (tons)                (tons)
1970
1975
1980
1986
17
33
79
127
34
176
917
800
51
209
996
927
• Approximately half of all loose Ni-Cd batteries  (20  percent of all  Ni-Cd
Batteries are loose) are assumed to be discarded the same year by the
consumer.

b The remaining loose batteries and all batteries  sealed within products
(appliances, toys, etc.) are assumed to be discarded after four years.
These constitute 90 percent of all Ni-Cd batteries.

Source:  EPA 1989.
                                   -  86 -

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large part to the increase in demand for the use of Ni-Cd batteries  in

portable consumer electronic equipment and in rechargeable throw-away devices

such as toys, hand-held power-vacuums, and other such items.

      D.  Potential Substitutes for Nickel-cadmium Batteries

      There are a wide range of potential substitutes for nickel-cadmium

batteries, including:

                  lithium secondary batteries;
                  silver-zinc batteries;
                  nickel-zinc batteries;
                  nickel-hydrogen batteries; and
                  primary batteries.

With the exception of primary batteries, however, none of these potential

substitutes has seen much, if any, commercial use in consumer products because

of technical complications, reduced service life, and high cost.

            1.  Lithium Secondary Batteries

            One of the more promising technologies is the rechargeable lithium

cell, which is already used to a very limited extent in some consumer

applications.  Lithium cells are manufactured with a variety of materials, and

include lithium-air batteries that allow air to circulate freely in  the cell.

According to one supplier, rechargeable lithium batteries have greater charge

capacity  than Ni-Cd batteries of a comparable size (SAFT 1989a).  There are

currently many limitations, however, to their use.  Lithium batteries are

currently much more expensive (at least twice the cost) of Ni-Cd batteries.

Their cycle  life is only  200-400 cycles, versus 1000 or more for Ni-Cd

batteries, and in addition, they are less tolerant to abuse.  Finally, large

cells are not yet available, although there is work currently being  funded to

investigate  and produce lithium cells for military applications such as

communications equipment  (Yardney 1989b).  Although lithium cells cannot be

used to power electric cars (normally powered by lead-acid batteries), there


                                     - 87  -

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 is a possibility  that  lithium  cells  could be  used for  this  application in the



 future  (SAFT  1989c).




      It  is simple  enough  to add circuitry  to the recharging  equipment to




 prevent overcharge, although it would  further increase  the  cost  of using




 lithium batteries.  Circuitry  to prevent a  deep discharge also is  required in




 the equipment in which the batteries are used, which precludes their  use in




 many applications in which Ni-Cds are  currently found,  and  may make the  cost




 of any product extremely high  (SAFT 1989a).   Because of these limitations,  it




 is likely that lithium rechargeable batteries will be found only in




 applications where  the higher  cost of  the batteries and controlling circuitry




 are not an obstacle, such as in computers.  In such applications,  the  cost  of




 the battery system  and controlling circuitry  is not large relative  to  the




 overall cost of the product (Yardney 1989b).




      Advantages of lithium rechargeable batteries include  their light weight,




 ability to provide  energy in freezing temperatures, and very high efficiency




 (Chemical Business  1989,  SAFT  1989c).  Possible applications for lithium




batteries include portable cellular phones,  lap-top computers, portable



 radios,  and military applications (Moli Energy 1989).




            2.  Silver-zinc Batteries




            Another battery technology currently in use is the silver-zinc




 system,  which is used primarily (90X of the time)  for  military and space




application* and has a high energy density (Kirk-Othmer 1978,  SAFT 1989c).




However, there are many limitations which may restrict its use in consumer




 applications such as the high cost of such batteries.   According  to one




 supplier,  silver-zinc batteries cost about five times  more than similar




nickel-cadmium batteries (Yardney 1989a).   This high cost  is due  in part to




 the cost of the silver, a precious metal.   Because of  the  value of  silver,





                                    - 88 -

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expended batteries would probably be recycled to recover the metal.  Recycling




could allow for some recovery of the initial cost of purchase  (Yardney 1989a).




      Another obstacle to widespread use of silver-zinc batteries  is their




rather limited service life; silver-zinc batteries typically last  100-200




cycles and have about a 2-year wet life (the wet life is the amount of time it




takes for the cell to degrade without cycling).  Because of these  limitations,




it is highly unlikely that silver-zinc batteries could ever succeed as a




substitute for the Ni-Cd system except in the very short term  and  for




applications where cost is no object (Yardney 1989b).




            3.  Nickel-zinc Batteries




            One battery system which generated a good deal of  interest during




the early and mid-1970s was the nickel-zinc cell.  It potentially  offers a




charge density greater than that available from nickel-cadmium batteries but




at a lower cost than silver-zinc.  Some research into improving the




performance of nickel-zinc batteries was funded by the U.S. government for use




in electric vehicles.  According to one company involved in that development




effort, interest in electric vehicles waned; although attempts were made to




continue the study, the funds were no longer available and the research was




essentially stopped (Yardney 1989a).  Although these previous studies focused




on large batteries such as might be found in electric vehicles, future




development might focus on smaller cells if such a demand arose.




      A primary advantage of a nickel-zinc system over the silver-zinc battery




is the cost.  Although its performance is not as high as its silver-based




counterpart, it is also not subject to the wide fluctuations in price




resulting from speculation in markets for precious metals such as silver.   In




spite of this, the price is currently quite high due to the developmental




nature of the Ni-Zn batteries produced thus far.  Although nickel-zinc





                                    - 89 -

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 batteries may be recycled, the metal recovery may not by worth the cost (SAFT

 1989c).   However, even if the cost of new cells is brought down, a major

 limitation in nickel-zinc cells is their short life.   Capacity of the battery

 drops rapidly with multiple cycles.   The cell can be  periodically

 "conditioned" by fully discharging the zinc electrode,  which restores some of

 the  original capacity.   After about  100 cycles,  however,  the cell can only

 reach about two-thirds  of its original capacity,  even after conditioning.   Due

 to its initially higher charge density (relative to a nickel-cadmium cell),

 such a loss of capacity still might  provide acceptable  performance if the  cell

 is conservatively rated.   Further  research  in this  area may alleviate some of

 these limitations and reduce  production costs (Yardney  1989b).

             4.   Nickel-hydrogen Batteries

             Another high  technology  battery system which currently  is  found  "

 only in very exotic applications is  the  nickel-hydrogen cell.  Its  gravimetric

 charge density* is slightly higher than that of a nickel-cadmium cell and the

 service life  is  somewhat  longer (Kirk-Othmer  1978).  The cycle life of the

 cell  is also  about double  (1,500-2,000 cycles) that of a Ni-Cd system  (Yardney

 1989a).  For  these reasons, nickel-hydrogen cells were originally developed

 for  satellite applications, where  this combination of characteristics is

 advantageous.  However, the hydrogen in the cell is in the gaseous form, and

 the operating pressure  is much higher, ranging from 3-20 times atmospheric

pressure, as compared to 0-3 atmospheres for a Ni-Cd cell.   Because of these

high operating pressures, construction is labor-intensive  and very expensive.

Unless significant breakthroughs are made in reducing  the  cost of
       The gravimetric charge  density  is  the charge density per unit of
weight, as opposed to unit of volume.
                                    -  90 -

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construction, the nickel-hydrogen system is likely to be found only in very




specialized applications (Yardney 1989a).




            5.  Primary Batteries



            Primary batteries are available in a variety of configurations.




The common carbon-zinc battery' has been replaced by the alkaline battery as




the dominant commercially available primary cell (Chemical Business 1989).




Other types of primary batteries include lithium batteries and mercury




batteries (Panasonic undated).



      Primary lithium batteries last up to five times as long as carbon-zinc




batteries (Chemical Business  1989).  They have a very long life and are often




used in watches and cameras.  Primary mercury batteries have a compact size,




long shelf life,  and excellent voltage  stability.  Mercury batteries  are often




used in watches,  calculators, cameras,  and hearing aids  (Panasonic undated).




      While  primary batteries do not contain cadmium, constant replacement may




be expensive  in applications  involving  high discharge rates.




       E.  Limitations  on Substitution



       The alternative  secondary battery systems listed all have significant




 limitations  when  compared to  the Ni-Cd  system.  In addition, many of  these




 technologies are  currently in an embryonic  stage of  development and their




 costs  are quite high.   As experimentation and  development proceeds, the



 limitations  as well as the costs  of these potential  substitute products may be




 reduced.



       In general, nickel-cadmium batteries have performance  characteristics




 which make them difficult to replace in consumer  applications.  These are as




 follows:
                                     - 91 -

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             •     A long cycle life that allows Ni-Cd batteries to be
                   installed in products where the batteries are not readily
                   accessible to the consumer.  A cordless product can then be
                   made that requires little attention on the part of the user.

             •     The charge density is comparable to that of many primary
                   cells.   The higher capacity of these products is an
                   advantage in some applications.

             •     Ni-Cd batteries  are relatively forgiving of misuse.   Slight
                   overcharging does not seriously damage their performance,
                   and deep discharge is acceptable except when several
                   batteries are arranged in series.

             •     Ni-Cd batteries  cost  significantly  less than other
                   rechargeable batteries  currently available,  with the
                   exception of lead-acid  systems  which are  not considered to
                   be  substitutes due  to the  scope  of  this report.

      Some of the  alternative  battery technologies  discussed  in this chapter

offer the potential for better performance  than Ni-Cd  batteries  in one  or more

aspects  (see  Table 31).  Unfortunately, cost  information  on possible

substitute consumer products  is not available at this  time because  of the

experimental  nature of  potential substitute technologies.  With sufficient

research and  development, however,   it is not unreasonable to hope that some of

these technologies (particularly lithium and nickel-zinc cells) can be

improved sufficiently to eventually compare with nickel-cadmium batteries.

      The solid performance and low cost of nickel-cadmium batteries make it

unlikely that there will be replacements in the near future.  In fact,

according to one industry contact (SAFT 1989b), if both Ni-Cd and lead-acid

batteries were eliminated immediately, substitute rechargeable batteries would

not be available in the short run due to cost and performance limitations.

This source expressed the belief, however, that there  is enough interest in

rechargeable batteries to develop alternate systems over time.
                                    -  92 -

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            Table 31.  Advantages and Disadvantages of  Substitutes
                          for Nickel-cadmium Batteries
Substitute Battery
Advantages
Disadvantages
Lithium Battery
•   Very light weight

•   Provide energy in
    freezing
    temperatures

•   Very efficient
Silver-zinc Battery
    Very high energy
    density
Nickel-zinc Battery
    Relatively high
    energy density
Nickel-hydrogen
Battery
    Twice the cycle
    life of a nickel-
    cadmium battery
Primary Battery
 (alkaline, lithium,
  and carbon-zinc)
    Over twice the
    cost of nickel-
    cadmium batteries

    Less than half the
    lifetime of a
    nickel-cadmium
    battery

    Sensitive to abuse
    (overcharging and
    deep discharging)

    Five times the
    cost of nickel-
    cadmium batteries

    Less than one-
    fifth the lifetime
    of a nickel-
    cadmium battery

    High cost

    Less than one-
    tenth the lifetime
    of a nickel-
    cadmium battery

    More expensive
    than a nickel-
    cadmium battery
    due to high
    atmospheric
    pressure required
    in the cell

    Replacement costs
    may be substantial
    in high discharge
    applications
Sources:  Yardney 1989a, 1989b, SAFT 1989a, Chemical Business 1989.

                                    - 93 -

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      F.  References

Chemical Business.  1989 (July/August).  "The Assault on Batteries," p. 35-36.

Kirk-Othmer.  1978.  Encyclopedia of Chemical Technology.  John Wiley and Sens
Publishing Co.,  Inc.  Vol. 3, pp. 569-639.

Moli Energy.  1989  (January).  Product literature on Molicel Lithium
batteries.

EPA.  1989 (January).  U.S. Environmental Protection Agency.  Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Panasonic.  Undated.  "Batteries," a publication of Panasonic, Secaucus, NJ.

SAFT America.  1989a (July 14).  G. Lupul.  Maryland.  Transcribed telephone
conversation with Donald Yee, ICF Incorporated, Fairfax, VA.

SAFT America.  1989b (July 17).  R. Vikmund.  Valdosta,  GA.  Transcribed
telephone conversation with Donald Yee, ICF Incorporated, Fairfax, VA.

SAFT America.  1989c (August 15).  P. Scardaville,  Director of Engineering.
Valdosta, GA.  Transcribed telephone conversation with Alex Greenwood,  ICF
Incorporated, Fairfax,  VA.

Yardney Battery.  1989a (July 13).  T.  Aretakis.   Connecticut.  Transcribed
telephone conversation with Donald Yee, ICF Incorporated, Fairfax, VA.

Yardney Battery.  1989b (July 20).  D.  Wissocker.   Massachusetts.   Transcribed
telephone conversation with Donald Yee, ICF Incorporated, Fairfax, VA.
                                    - 94 -

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VII.  GLASS AND CERAMIC PRODUCTS

      A.  Overview of Glass/Ceramic Products

      Glass is an inorganic, brittle, transparent or translucent material that

consists of a mixture of crystalline materials such as silicates, borates, or

phosphates combined by melting at high temperatures and then cooling  to a

rigid condition.  Silicates are the main constituent in glass.  Silica by

itself makes a good glass, but its high melting point (about 1700 C°) and its

high viscosity in the liquid state make it difficult to melt and work.

      Glass manufacturing begins by mixing and melting the raw materials, such

as silicates and limestone.  After melting, the molten glass, called  metal, is

refined, freed of bubbles, and then cooled.. Heat treatment follows,  and the

glass is strengthened.

      Ceramics are non-metallic materials such as clay, produced by firing at

very high temperatures.  Ceramics are usually hard, brittle, and are  good

electrical and thermal insulators.  Ceramic products are often divided into

two groups:

      •     pottery and brick are shaped or formed before high-temperature
            treatment; and

      •     glass and cement are shaped afterward.

      Glazes and enamels are also used with glass/ceramic products.   Enamel or

porcelain enamel is a decorative or protective glassy coating which is applied

to metal or glass.  Glass color enamels are used to decorate and label glass

objects.  Glaze is a glassy coating applied on ceramics.

      B.  Uses of Lead and Cadmium in Glass/Ceramic Products

            1.  Use of Lead in Glass/Ceramic Products

            Lead monoxide often is used as an intermediate or modifier in

glass products.  As an intermediate, lead monoxide adds to the brilliance of
                                     - 95  -

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the glass products, and as a modifier, it lowers the melting temperature,

thereby simplifying glass processing.  Alkali metal* oxides also are widely

used and are inexpensive, but glass produced with these products may require

modifications in the manufacturing processes when substituted for lead

products and can not fully replace lead in the glass formulation (Nordyke

1984).

      Lead-containing glass also can shield high energy radiation and the high

refractive index of lead yields excellent properties for optics and for hand-

formed art ware.  The glass and ceramic use areas identified in the EPA 1989

report are discussed in the following section.  In addition, Table 32 lists

the special properties that are associated with lead-based glass/ceramic

products and specific glass/ceramic products that require these properties.

                  a.  Television and X-ray Shielding Parts

                  Leaded glass is used in three main parts of television

picture tubes:  in the neck surrounding the electron gun, in the funnel that

provides structural integrity, and in the faceplate or panel used in the

television screen.  About 2.25, 22.5, and 28.4 percent lead monoxide is used

in the faceplate, funnel, and neck, respectively.   Lead is used because it

absorbs radiation from the electron gun.   Linear absorption (or attenuation)

coefficients**  that  increase as  lead  oxide content increases and the

thickness of the absorbing material (in this case,  leaded glass) are useful

indicators in determining the effectiveness of a compound for absorbing

radiation.  To achieve a low dosage rate of radiation,  a material with a high
     *  Alkali metals are metals in Group 1A of the Periodic  Table (e.g.,
lithium, sodium, potassium, etc.).

        The linear  absorption  coefficient (u)  is computed by  multiplying the
mass absorption coefficient of the compound (in this case,  lead oxide) by the
density of the absorbing material (Nordyke 1984, Corning 1989d).

                                    - 96 -

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         Table 32.   Properties Lead Imparts to Glass/Ceramic Products
Properties
                                          Associated Glass/Ceramic Products
Low Melting Range

Wide Softening Range
(Processability)

High Index of Refraction

Resonance

Radiation Absorption


Good Electrical  Properties
Enamels

Fluorescent lighting and neon sign
tubing

Optical Glass; Crystalware

Crystalware

Leaded glass in televisions and X-
ray shielding

Glazes and Enamels; Neon sign tubing
 Source:   Nordyke  1984.
                                     - 97 -

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 linear absorption coefficient, large thickness, or combinations of these



 factors can be used.




       From a design standpoint, the thickness of these television parts tends




 to be fixed by the strength requirements of the pieces.  The faceplate,




 funnel,  and neck are 1.14,  0.25,  and 0.25 cm thick,  respectively (Nordyke




 1984).   The Joint Electron Device Engineering Council of the Electronics




 Industry Association has set the  radiation standard  at a dose rate of 0.5 mR/h




 (milliroentgen per hour) measured 5 cm  from the tube face (Nordyke 1984).   For




 this  dose rate and these thicknesses, linear absorption coefficients  are




 typically 28,  62,  and 90,  for the faceplate,  funnel,  and neck,  respectively,




      As  televisions  have  increased in  size,  voltage  requirements  have  also




 increased resulting  in pressure on manufacturers to produce  television  parts




 with higher  radiation absorption  characteristics (Nordyke 1984).




 Manufacturers  have typically  met  this demand by increasing the  lead content in



 some cases by  as much  as two-fold.




      Leaded X-ray shielding  glass  is found in areas other then televisions




 including hospitals, nuclear  power plants, or any other place where radiation




 is prevalent;  these sources of lead, however, are not expected to contribute




 to lead discarded in MSW.  Lead content varies from 35 to 82 percent lead




 oxide in X-ray shielding glass in these applications.




                  b-  Fluorescent Tubing and Light  Bulbs




                  Lead is used in the outer envelope  of fluorescent lighting




and neon sign tubing because of its excellent electrical resistivity




properties (high electrical resistance)  and because its low melting




 temperature allows easy processability (Nordyke 1984).   It is believed that




the lead content in these envelopes is small -- less  than 10  percent  (Sylvania




and Laxman 1989) while the lead content  for neon sign tubing  is  about  30





                                    . 98 -

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percent lead oxide  (Nordyke 1984).  Light bulbs contain leaded glass at a

concentration of 20 to 30 percent lead oxide in the flare and exhaust tube,

both of which are part of the mount that is at the base of the bulb (EPA

1989).  In addition to providing excellent insulation at the base of the bulb,

lead is also used because of its ease of processability.

                  c.  Optical and Ophthalmic Glass

                  Optical leaded glass is found in all types of concave and

convex lenses principally because of its high index of refraction.*  Optical

glass can be classified into ophthalmic and non-ophthalmic uses.  Ophthalmic

glass is used to correct vision deficiencies.  About 50 percent of ophthalmic

glass is used in single-vision spectacles which have a moderate refraction

index of 1.523 and use lime glass rather than leaded glass (Nordyke 1984).

The remainder of ophthalmic glass is used in multifocal lenses.  Lead oxide

makes up 5 to 10 percent of the segment** used  in  multi-focal  lenses  (Corning

1990) and is used to achieve refraction indexes up to 1.7 (Nordyke 1984).

      Non-ophthalmic optical glass includes camera and telescopic lenses, and

fiber optics; lead oxide content in these uses ranges from 20 to 30 percent in

cameras and telescopes and from 30 to 40 percent for fiber optics (Schotts

1989).  Photochromatic glass or glass that changes color when exposed to light

uses a marginal amount of lead oxide, typically less than three percent

(Corning 1989d).
       The index of refraction can be defined as the ratio of the velocity of
light in air to the velocity of light in glass.  Generally, as lead content
increases so does the refractive index (Nordyke 1984).

       The  segment  is  the  point of juncture  of two  lenses,  typically making
up less than 10 percent of the surface area of bifocal lenses (Schotts 1989).

                                    - 99 -

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                  d.  Lead Crystalware


                  Lead crystal is defined by its lead oxide content but the

term lead crystal is not always applied uniformly.   Full lead crystal is


defined as containing at least 32 percent lead oxide, but glassware with lower


percentages of lead oxide, typically about 24 percent, is often sold as lead

crystal (BCR 1990).   The use of lead crystal can be traced back to ancient


Russian glasses of the eleventh century.  The chemical composition of modern

lead crystalware has not changed appreciably, although improved refractories

and melting furnaces, and purity of raw materials have helped to enhance its


brilliance, smoothness, resonance, and temperature stability properties

(Nordyke 1984).


                  e.  Piezoelectric Ceramics


                  Combining lead zirconate and lead titanate form the


piezoelectric family of ceramic products known as PZT (lead zirconate


titanate).  Piezoelectricity means "pressure electricity" and with ceramics,


PZT can serve as a transducer for electrical and mechanical energy.  The use

of PZT is found mainly in small appliances such as watch alarms, automobile

cigarette lighters,  and measurement devices where a small mechanical

displacement creates a low voltage.  PZT contains about 68 percent lead oxide

(Piezo Kinetics 1989).  The family of materials designated PZLT for lead-

lanthanum- zirconate -titanate is commonly used in electrooptic applications
                                                                     •-}
(Nordyke 1984).   An electrooptic application such as maintaining memory in a


calculator after turning it on and off is due to the piezoelectric


characteristics of PZLT (Nordyke 1984).
                                    -  100  -

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            2.   Use of Cadmium in Glass/Ceramic Products

            The uses of cadmium in glass and ceramic products are commonly as

a pigment in a glaze, as a colorant in the glass itself, or as a phosphor*

(EPA 1989).  Except for its use in colorants and glazes, the use of cadmium

associated with glass and ceramics is less than 5 percent of the total

production of cadmium (Blythe 1990, Cadmium Council 1989).  The use of cadmium

in the production of colorants is discussed in Chapter II on plastics.

Cadmium- and lead-based glazes and enamels used with glass/ceramic products

are discussed in the following section.

            3.   Use of Lead in Enamels and Glazes

                  a.  Applied to Metal

                  Lead compounds are used in enamel compositions as fluxing

agents (i.e., to aid the softening or melting of the enamel).  This allows the

successful application of the enamel at relatively low temperatures.  As

fluxing compounds, lead compounds offer the advantage of increasing the

brilliance and smoothness of the enamel even when used in large quantities.

Lead also increases resistance to chipping, improves elasticity, and increases

corrosion resistance.  The amount of lead in an enamel will depend on the type

of metal to which it is applied.  Enamels used on cast iron contain only from

0 to 3 percent lead bisilicate.

      Using lead enamels on steel broadens the types of steel that can be

successfully enameled.  When enamels are applied below the strain point of the

steel, the strength and warpage characteristics are not damaged.  The flux

characteristics of lead allow enamels to be applied below this point.  Lighter
       A phosphor is a phosphorescent substance that emits light when excited
by radiation.  Common applications include mercury-vapor lamps and fluorescent
tubes (EPA 1989).

                                    -  101  -

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gauge steel can be used as a result.  Typical leaded enamels applied to steel




contain between 2 and 7 percent lead.




      Enamels used on the limited number of aluminum alloys that can be coated




are all leaded.  These enamels can contain between 30 and 45 percent lead




oxide.  The use of lead in the enamel is necessary because of the low maturing




temperature of aluminum.




                  b.  Applied to Glass




                  Glass color enamels are used to decorate and label glass




objects.  Lead enamels are used for glassware primarily as a flux.  The lower




melting points which can be achieved with lead are important in preventing the




glassware from deforming during firing.




      Four properties are important for glass enamels:   stability of




composition, chemical durability,  coefficient of expansion, and melting




temperature.  Stability is necessary so that the enamel will not react to form




compounds which will be harmful to the color or the item.   Chemical resistance




to acids and alkalies serves to protect enamels from damage in their contact




with food, dishwasher detergents,  or attack by weather.   Enamels must expand




slightly less when heated than the host to which they are  applied or the




enamel will craze, peel, or crack when fired.   Glass enamels must have a




melting temperature far enough below the softening point of the preformed




glass to which they are applied so that the article will not be deformed.




      Formulation of enamels for glassware is also similar to the formulation




enamels used on metals.  The requirement for lower firing temperatures




generally increases the use of flux agents.  Lead oxide is the primary flux in




glass enamels.  Due to concerns about the toxicity of lead, industry has put




significant effort in reducing lead in enamels used to  decorate glass.   Most




of the progress has resulted in enamels which prevent the  lead from becoming





                                    -  102  -

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soluble in a range of acidities, thus preventing glassware  from  posing




toxicity concerns during use.  Most enamels, however, are still  based on  lead




flux.  These enamels contain 50 percent lead oxide.




                  c.  Glazes




                  Lead also is used in glazes for ceramics  as a  flux or




softening agent.  Lead glazes are generally more tolerant to application




variables than non-lead glazes. They can be fired at lower  temperatures,  and




resist crazing, cracking or splitting due to expansion and  contraction during




firing,  The lower temperatures attained allow the use of a broader range of




pigments (Nordyke 1984).   Glazes can contain 50 to 60 percent lead oxide  (EPA




1989).




            4.   Use of Cadmium in Enamels and Glazes




            Cadmium is used in glazes and enamels as a pigment (e.g.,  cadmium




sulfoselenide red) and as a stabilizing agent -of the cadmium pigment (cadmium




oxide).  Without the stabilizer, the cadmium pigment would become black under




firing (Nordyke 1984).   The use of cadmium as a pigment is discussed in the




chapter on plastics (Chapter II).




      C.  Consumption of Lead and Cadmium in Glass/Ceramics  Products




      Table 33 lists the discards of lead in glass/ceramic products from 1970




to 1986.  Leaded glass used in televisions accounts for by far the largest




quantity of lead discards,  representing 85 percent of the lead in




glass/ceramic products discarded in MSW in 1986.   Discards of lead from glass




and ceramics in MSW are expected to steadily increase and are projected to




rise to 91,000 tons by the year 2000 (EPA 1989).




      Table 34 presents the discards of cadmium in pigments  for  glass,




ceramics,  and miscellaneous products.   Use of cadmium in glass and ceramic




products accounts for a relatively minor portion of cadmium  discards in MSW.





                                    - 103  -

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        Table 33.   Discards of Lead in Glass and Ceramics in MSW




Year
1970
1975
1980
1986

Discards of
Lead from Glass
in TV Sets"
(tons)
10,395
17,969
27,756
52,247
Discards of
Lead from
Light
Bulb Glass"
(tons)
491
506
635
672

Discards of
Lead from All Other
Glass and Ceramics0
( tons )
3,366
3,934
5,235
7,795
Total Lead
Discards
from Glass
and
Ceramics
(tons)
14,252
22,409
33,626
60,714
• Includes adjustment for imports.   TV's  are  assumed to  have  an 8  year
life.

b Light bulbs are assumed to be discarded one year after manufacture.

c All other glass and ceramics are  assumed to be  discarded 3  years
after manufacture.

Source:  EPA 1989.
                                 -  104 -

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             Table 34.  Discards of Cadmium in Pigments  for
           Glass, Ceramics, and Miscellaneous Products in MSW
                                                        Total Discards  of
             Cadmium                                   Cadmium  in  Pigments
          Discarded in          Cadmium Discarded      for Glass,  Ceramics
          Pigments for           in Pigments for        and Miscellaneous
       Glass and Ceramics*   Miscellaneous Products1"        Products0
Year         (tons)                   (tons)                  (tons)
1970
1975
1980
1986
32
27
23
29
79
65
56
70
111
92
79
99
a Half of the glass and ceramics with cadmium pigments is assumed to
end up in MSW.  Discards are assumed to be in the year of manufacture
for the glass product.  The cadmium used to stabilize cadmium pigments
in glass and ceramics is assumed to be included with the figures for
the cadmium in the pigments.

b Includes pigments in products other than plastics, rubbers, and
glass/ceramics.   Products are assumed to be discarded in the year of
manufacture.

0 Includes pigments other than those found in rubbers and plastics.

Source:  EPA 1989.
                                 - 105 -

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In 1986, 29 tons of cadmium were discarded in glass/ceramic products.  This

quantity is less than 2 percent of the total cadmium discarded.

      D.  Potential Substitutes for Lead and Cadmium in Glass/Ceramic Products

      Substitution for lead- and cadmium-based glass/ceramic products usually

involves switching to alkaline earth metals* (primarily strontium and

barium), and zirconium that are expensive in comparison to lead and cadmium.

In the case of potential substitutes for lead-based glass/ceramic products,

the performance properties of the substitutes lack the refractive indices, the

radiation absorption characteristics, and the processability of lead-based

glass/ceramic products.  There are also reports of supply problems with

strontium and zirconium (Corning 1989c).   Table 35 presents the potential

substitutes for lead and cadmium in glass and ceramic products.

            1.  Television and X-ray Shielding Parts

            Zirconium is a potential substitute for lead in faceplates, but

its use would increase the cost of the faceplate by six percent (Corning

1989c) .  Zirconium products would require higher processing temperatures

necessitating possible changes in manufacturing equipment.   Television

manufacturers have already begun to use zirconium-based faceplates that

provide better resistance to radiation darkening (browning) than lead-based

faceplates (Corning 1989c).

      Strontium and barium are potential substitutes for the funnel and neck

portions of X-ray shielding substitution but as much as 50 percent more

strontium carbonate than lead oxide would be required to achieve the sane

radiation protection at current thicknesses of funnels and necks.   A similar

percentage increase of barium carbonate would be required to substitute for
     * Alkaline earth metals include calcium,  barium,  strotium,  and radium
 (i.e., Group IIA fo the Periodic Table).

                                    -  106 -

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  Table  35.   Potential Substitutes for Lead and Cadmium in Glass and Ceramics
          Use
       Potential
      Substitute
 Comments  on Potential
      Substitutes
GLASSES
   Television Parts:
     Neck and Funnel
     (28 and 22
     percent PbO
     respectively)

      Faceplate
      (panel) (2
      percent PbO)
   Leaded Glass:
      X-ray shielding
      Neon/Fluoroe-
      scent Tubing

      Light Bulb
      Optical Glass
•  Strontium
•  Barium
•  Zirconium
•  Thicker glass
•  Strontium/Barium
•  Cerium/Alkaline
   Earth Metals

•  Barium/zinc oxides

•  Zinc, lithium and
   barium oxides
   Processing
   problems, lower
   durability, larger
   quantity required
•  Supply problem,
   marginal cost
   difference (6
   percent higher)
•  Increased space
   requirements and
   decreased visual
   clarity

t  Expensive

•  Processing problems
•  Under development;
   processing problems

•  Lower index of
   refraction
   achievable than
   with lead
                                                        •  Commercially
                                                           available
                                    -  107  -

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Table  35.    Potential  Substitutes  for Lead and Cadmium  in Glass and Ceramics
                                  (Continued)
                                  Potential             Comments on Potential
         Use                      Substitute                 Substitutes
CERAMICS
Glazes/Enamels              •Zirconium dioxide          •  Satisfactory
                                                           brilliance and
PZT/PZLT (68 percent        •Chrome tin salt               alkali resistance;
PbO)                                                       some application
                            •Barium Lead Titanate          problems
                            (10 percent lead)
                                                        •  Color instability

                                                        •  Not as piezoelec-
                                                           trically efficient;
                                                           less expensive;
                                                           can't be used in
                                                           temperatures over
                                                           100"C;  25 percent
                                                           less expensive
                            •Quartz
                                                        •  Not as piezoelec-
                                                           trically efficient

                                                        •  3-4 times more
                                                           expensive
                            •Rochelle Salts
                                                        •  Not effective in
                                                           humid environment;
                                                           more efficient


Sources:  Blanche 1989; Corning 1989a, 1989b,  1989c,  1989d; Degussa 1989;
          Piezo Kinetics 1989; Sylvania 1989.
                                    -  108  -

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 lead oxide (Corning 1989d).  Significant processability and durability




 problems exist with strontium and barium glass products and reformulation




 costs could be substantial.  The costs of strontium and barium are higher than




 lead (Corning 1989d).   To achieve the required density associated with proper




 x-ray shielding,  a 50  percent weight increase would be necessary.  This




 increase would raise the costs of substitute funnels and necks even more as




 well as increasing the technical processing problems (Corning 1989d).




             2-   Fluorescent Tubine and Light Bulbs




             Bismuth alloys containing smaller amounts  of lead oxide are




 potential substitutes  for neon sign tubing  (Piezo  Kinetics  1989).   Cerium and




 other alkaline  earth metals have been suggested as potential  substitutes  for




 outer envelopes used in fluorescent lighting and for the  flare  and  exhaust




 tube used in  light  bulbs.   These potential  substitutes  lack the processability




 and  durability of  lead based products  (Sylvania 1985).




            3.  Optical  and Ophthalmic Glass




            Based on refraction  indices, substitution to barium and zinc




 oxides  is possible  in  optical glass  requiring refractive indices below




 approximately 1.6 (Nordyke  1984).  Lanthanum is a potential substitute for




 ophthalmic and non-ophthalmic optical glass requiring high indices of




 refraction (above 1.6); however, research is still preliminary (Schotts 1989).




 One  industry contact noted  that  in addition to the technical feasibility of




 lanthanum substitution being unknown, the cost of this  substitution would be



very high (Corning 1990).




            4.  Lead Crystalware




            By definition, substitute glassware that does not  contain at least




the specified percentage of lead oxide would not be considered lead




crystalware.   Although  the functional aspects of leaded  crystalware  could  be





                                    - 109 -

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replaced many of the quality aspects could not.  For example, the smoothness




and temperature stability of lead crystalware is hard to replace with other




compounds (ProChem Tech 1989); unleaded glass such as lime glass could be




considered a substitute, but many of the properties of leaded glass (e.g.,




brilliance, strength, and clarity) could not be maintained.




            5.   Piezoelectric Ceramics




            Three potential substitutes for lead-based PZT and PZLT ceramics




have been mentioned by industry sources.  A reduction in lead content from




about 68 percent lead oxide to about 10 percent lead oxide can be achieved by




switching to barium titanate products  (Piezo Kinetics 1989).  Barium titanate




was the first commercially available ceramic and is still widely used in sonar




detection and ultrasonic cleaning devices.  Barium titanate  is about 50




percent as efficient as PZT (i.e, less voltage produced for  a given mechanical




displacement) and barium titanate cannot be used at temperatures above 100*C




 (Piezo Kinetics 1989).  PZT can be used at temperatures up to 300°C.  The cost




 of barium  titanate piezoelectric ceramics is about 25 percent less than PZT




 (Piezo Kinetics 1989).



      The  temperature  limitation makes barium  titanate unsuitable for use as




 an igniter in  glass  appliances and  cigarette lighters.  In general, due to the




 lower cost of  barium titanate it has already been  substituted for PZT where




 feasible.   Some additional  substitution may be possible, but with a sacrifice




 in performance in other consumer  electronic applications.




       Quartz is also piezoelectric  and is used in  applications such as radio




 tuners  that require a high  degree  of frequency control.  Quartz  costs 3 to 4




 times more than PZT and is  10 to  20 percent  less efficient  (Piezo Kinetics




 1989).
                                     -  110  -

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       The final potential substitute is Rochelle salts.  Although they are 25




 to  30 percent more efficient than PZT,  they do not work well in humid




 conditions,  including most ambient air, making them unsuitable for most




 applications (Piezo Kinetics 1989).




             6.   Glazes and Enamels




                   a.   Lead-Free  Glazes  and Enamels




                   Lead free  enamels  were introduced in the  early 1980s and




have  found application on lighting fixtures and liquor and  cosmetic




containers.   Because  their chemical  resistance  is  much lower than that of




standard  lead-based enamels,  they  are finding a relatively  limited use.




According to  Nordyke  (1984),  no  lead-free  systems  are  available  for use on




cookware, tableware,  and  other areas that  demand excellent  chemical




resistance.   In  a  typical  glass  enamel,  lead oxide  accounts  for  56 percent ofe




the formulation.   The  lead oxide can be  replaced by using a  formulation with




up to 40 percent zinc  oxide  (ZnO), lithium  oxide (Li20), calcium oxide (CaO) ,'




barium oxide  (BaO), and antimony oxide  (SbO), and the remaining 16 percent can




be allocated  to  other  ingredients of the formulation.




      In addition, an  enamel  system free of lead and cadmium consisting of




zirconium dioxide  (Zr02) has  been recently developed (Gillier 1989).   Used for




glass decorating,  the  enamel has high brilliancy and alkali and dishwasher




resistance.   The enamel system can be colored with pigments to 13 shades.   The




range of colors available  is specifically intended for the decoration of




dinnerware,  glass-ceramics, and borosilicate and opal glass  but does  not




include red or bright yellow without the use of cadmium.




      With the absence of lead,  lack of brilliance  is a problem.   Lithium  is




added to improve brilliance,  but this can have  a negative effect  on the glass




to which it  is applied due to ion exchange, thereby weakening the glass.   In





                                   - Ill -

-------
addition, these enamels have higher and narrower firing temperatures than




leaded enamels (Degussa 1989).




      Potential substitutes for lead in glazes appear to be scarce because of




the number of excellent properties currently available from lead-based glazes.




As discussed earlier, these properties include fusibility, smoothness,




brilliancy, and mechanical and chemical resistance.  A potential substitute




consisting of a chrome-tin salt has been identified for pink glazes (Blanche




1989).  More development work is required on this compound because of color




instability in lead-free glass.  Lead-free decorative glazes are also being




developed, but they  are experiencing difficulty because the lead-free glazes




actually encourage greater release of lead from the leaded glazes over which




they  might be applied  (Degussa 1989).




      The cost of these unleaded glazes and enamels is not significantly




different than leaded versions, but  they may add to the cost of the final




product  due to higher  firing  temperatures and more precise processing




conditions  that would  be required  (Degussa 1989).




                  b.  Cadmium



                  As mentioned earlier, cadmium  is used in glazes and enamels




 as a color  stabilizer  for  cadmium  pigments  (bright reds and yellows). Cadmium




 pigments are  discussed in  the plastics  chapter and Chapter II.
                                     -  112  -

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      E.  References

Blanche, S.I.  1989.  "Chrome-Tin Pink Glazes," Ceramic Engineering Scientific
Proceedings. Vol. 10, pp. 65-68.

Blythe Colours. 1990 (March 27).  G.R. Streatfield, Technical Director,
Cresswell Stoke-on-Trent, England.  Comments on draft of " Use and Substitutes
Analysis For Lead and Cadmium Products in Municipal Solid Waste.

BCR 1990 (March 5).  British Ceramic Research Limited.  D.W.F. James, Chief
Executive.   Penhull Stoke-on-Trent, England.  Comments on draft of "Use and
Substitutes Analysis For Lead and Cadmium Products in Municipal Solid Waste."

Cadmium Council.  1989 (May 25).  H. Morrow.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  1989a (July 21).  T. Seward.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Optics.  1989b (July 21).  R. Thompson.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  1989c (May 30).  D. Lopata.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  1989d (July 26).  J. Connelly.  Transcribed telephone
conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Corning Glass.  1990 (October 3).  C. McCarthy.  Letter to Gary Cole, U.S.
Environmental  Protection Agency, Washington, DC.

Degussa Corporation.  1989 (August 14).  D. Gillier.  Transcribed telephone
conversation with Louis Gardner, ICF Incorporated, Fairfax, VA.

EPA.  1989  (January).  U.S. Environmental Protection Agency.  Characteristics
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970  to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Gillier, D.   1989  (February).  "Beauty and the Beast:  Colors Shine Without
Lead,"  Ceramic Industry, pp. 21-22.

Nordyke, J..   1984.  Lead in the World of Ceramics.  The American Ceramic
Society.  Westerville, OH.

Piezo Kinetics Inc.  1989 (May 30 and July 27).  R. Turner.  Transcribed
telephone conversation with Peter Weisberg, ICF Incorporated, Fairfax, VA.

Pro  Chem Tech.   1989 (May 31).  T. Keister.  Transcribed telephone
conversation  with  Peter  Weisberg, ICF Incorporated, Fairfax, VA.
                                    - 113 -

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Schotts Glasswerke.  1989 (July 27).   R.  Scheller.   Transcribed telephone
conversation with Peter Weisberg,  ICF Incorporated,  Fairfax,  VA.

Sylvania and Laxman Ltd.  1989 (June 1).   R.  Marlor.   Transcribed telephone
conversation with Peter Weisberg,  ICF Incorporated,  Fairfax,  VA.
                                    -  114 -

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VIII.  BRASS AND BRONZE PRODUCTS




      A.  Overview of the Copper Alloys Industry




      Copper is combined with varying amounts of other metals to produce,




among other alloys, brass and bronze.  The properties of these alloys are




varied by incorporating certain materials to fit a wide range of uses.  Copper




alloys generally have good mechanical properties, corrosion resistance,




workability, and conductivity.  Lead is included in some forms of brass and




bronze to improve workability (Copper Development Association 1989).




      Brass is generally an alloy of copper and zinc with small additions of




other metals.  Brass products may be cast or formed by rolling,  extrusion,




forging or other processes.  The varieties of brass are defined by their




content:  red-gold brass is 75-85 percent copper, yellow brass consists of 60




to 70 percent copper, naval brass contains 2 percent tin, and leaded brasses




contain lead in quantities greater than 2 percent (EPA 1989).   Typically 3




percent lead is found in free machining brass (Kirk-Othmer 1978).




      Lead is generally added to brass to improve the free machining




characteristics of the alloy (Copper Development Association 1989,  Wolfenden




and Wright 1979) .   Lead also may be present as an impurity in some brass




products due to the lead content of scrap materials used in the  manufacture of




brass materials.  Lead is present, therefore, in virtually all kinds of brass




to a small degree (Kirk-Othmer 1978).




      Traditionally, bronze has been defined as an alloy of copper and tin,




but currently is described as containing any of a variety of metals including




aluminum, manganese, silicon, or tin in combination with copper,  which is




always the principle ingredient.  Leaded bronze may contain up to  30 percent




lead (EPA 1989) which is included because it improves workability  and




conformability (Kirk-Othmer 1978).  In general,  bronzes can be grouped into





                                    -  115  -

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leaded, tinned, and high strength bronzes with the latter groups being




successively harder and stronger (Kirk-Othmer 1978, Glaeser 1983).




            1.  Use of Lead in Brass




            Because lead is insoluble in copper it remains as free lead




globules distributed throughout the alloy.  The lead globules lend the alloys




the properties associated with softness such as improved lubrication




characteristics, decreased fatigue strength, and improved conformability




(Concast Metal Products 1989, Glaeser 1983).  The improved machinability that




lead adds to leaded brass has led to its use in the manufacture of screw




machine parts and plumbing goods (Copper Development Association 1989).




Leaded brasses are not used in the majority of copper alloy applications




because these properties are not needed and the increased lead reduces other




important properties such as light weight, conductivity and strength (Copper




Development Association 1989).




            2.  The Use of Lead in Bronze




            Leaded bronze is used mainly in machine parts such as bushings and




bearings where the lead adds to the natural lubricity of the parts and




decreases the likelihood of mechanical seizures due to interruption or loss of




lubricant (Concast Metal Products 1989).  The conformability of leaded bronze




allows parts  to wear into best fit through use (Glaeser 1983) .   Highly leaded




bronzes are not used where impact or heavy, oscillating loads may be




encountered as a consequence of their lower strength and hardness.  Lead also




produces hot  shortness (brittleness under red-heat),  and therefore exceeding




the maximum frictional temperature is of concern (Glaeser 1983).




       B.  Consumption of Lead in Brass and Bronze




       Due to  the narrow scope of applications, the majority of end products




made  from leaded brass and bronze are not disposed in MSW, but rather in





                                    -  116 -

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industrial waste facilities.  Table  36 shows  lead  in brass  and bronze




discarded at MSW for the period from 1970-1986.




      C.  Potential Substitutes for  Lead in Brass  and Bronze




      Two methods can be used to substitute for lead in brass and bronze.




Alternative metals can be incorporated with copper to produce alloys with




similar properties to lead-containing products or  alternative materials  (e.g.,




plastics or other materials) can be  used in the final products.  It is easiest




to consider potential substitutes by use since leaded brass and bronze share




many functions.




      Bearings and fittings made from unleaded tin bronze and aluminum bronze




are already used for heavier load applications for which leaded bronze is not




hard enough.  These products could be used for the softer leaded bronze, but




would lack the natural lubricity of  leaded bronze.   A lubricant such as grease




or silicon would be required to prevent equipment seizure when fabricating




certain items made from these harder materials (Concast Metal Products 1989,




Kirk-Othmer 1978).   The hardness of  these replacements would also necessitate




that other parts with which they come in contact during use be made from




equally hard materials.  Engineering and design of machinery would also need




to be more precise due to the loss of wear-in properties associated with




leaded brasses and bronzes (Concast Metal Products 1989,  Glaeser 1983).




      Machinable leaded brass and bronze used for screw parts and plumbing




fixtures can be substituted for by other copper alloys to a large degree.  The




addition of tellurium, selenium, or  sulfur offers the possibility of improving




the machining characteristics of copper and its alloys without the use of




lead.  These materials affect the metallurgy of copper in ways analogous to




the effect provided by lead.  Selenium, tellurium and sulfur also are




insoluble in copper and thus remain  as free globules which provide points in





                                    - 117  -

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      Table 36.  Discards of Lead in Brass and Bronze in MSV
Year
1970
1975
1980
1986
Domestic
Lead Discards'
(tons)
20,485
23,699
20,044
15,660
Lead in
Imports/Exports15
( tons )
N/A
N/A
165
405
Gross
Discards
(tons)
20,485
23,699
20,209
16,065
Net Discards
into MSWC
(tons)
410
474
404
321
N/A - Not Available.

a Assumes 10 year product life.   Quantities  are  amounts  of lead
consumed in brass/bronze production ten years earlier.

b Data not available some years.   Negative numbers  denote  net
exports.

c Assumed to be 2 percent of all  discards.

Source:  EPA 1989.
                              -  118  -

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the microstructure for breaks to form.  They do not provide, however,




machinability at the same level as lead and increasing the consumption has a




rapidly diminishing effect.  Compared to free-cutting brass  (61 percent Cu, 3




percent Pb,  36 percent Zn) as a standard of 100, copper has  a machinability




rating of 20, and sulfur copper (99.7 percent Cu, 0.3 percent S) and tellurium




copper (99.5 percent Cu, 0.5 percent Te) both have a machinability rating in




the range of 85-90.  The effect of adding these materials is the same for many




other brass alloys and for the tin bronzes (Kirk-Othmer 1978, Copper




Development Association 1989).




     The choice of a potential substitute depends to a large extent on the




properties that the consumer requires most.   Different substitutes will be




chosen if hardness, color, strength,  or another property is critical or must




remain constant.   The costs of potential substitute alloys depend on the costs




of their components which are subject to the influence of world markets.




Table 37 presents substitute products and some of their disadvantages.   Table




38 presents  costs for some representative lead-containing and potential




substitute alloys.




     Other potential substitutes for  leaded  brass can replace specific  end




products.  For example,  some plumbing fixtures and valves currently




manufactured with brass  or bronze  may be replaced by PVC  or other  plastic




materials (Cohen 1987),  but these  materials  are  not suitable  for the bulk  of




brass and bronze applications.   Machined screws  may be replaced by steel




screws or another machinable metal  depending on  the importance  of  corrosion




resistance (Concast Metal Products  1989).
                                   - 119 -

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             Table  37.   Potential  Substitutes  for Lead-based  Brass
                              and  Bronze  Products
Use
Potential Substitute
Disadvantages
Machined Products
     Plumbing
     Fixtures,
     Machine screw
     parts
 Bushing/Bearing
 Products
Steel
PVC
                            Tellurium bronze
                            Selenium bronze
                            Sulfur bronze
Tin bronze


Aluminum bronze


Manganese bronze
Poor corrosion
resistance

Not able to handle all
applications; poor
shear resistance

Not commercially
available; marginal
difference in
machinability

Not commercially
available; marginal
difference in
mach inab i1i ty

Not commercially
available; marginal
difference in
machinability

Harder, requires
lubrication

Harder, requires
lubrication

Harder, requires
lubrication
 Sources:   Copper Development Association 1989, Nielsen Undated,
           Kirk-Othmer 1978.
                                    - 120 -

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Table 38.  Cost:  Lead-based Brass and Bronze Products
            and Their  Potential  Substitutes
                                         Cost
               Product                  ($/lb)
        Machined Products
             Leaded brass               $1.10
             Leaded bronze              $1.40
             Steel                      $0.45
             PVCa                       $1.24
             Tellurium bronzeb          $3.00
             Selenium bronzeb           $3.00
             Sulfur bronzeb             $3.00

        Bushing/Bearing Products
             Leaded bronze              $1.40
             Tin bronze                 $2.00
             Aluminum bronze            $0.70
             Manganese bronze           $0.70
        8 Costs presented for PVC are  based
        on a comparison of new products (e.g.,
        PVC products cost an average of 13
        percent more than equivalent brass
        parts).

        b Not widely available so costs are
        rough estimates based on inputs
        (Copper Development Association).

        Sources:  Nielsen undated, Copper
                  Development Association
                  1989, Wall Street
                  Journal 1989, Channel 1989.
                        -  121  -

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      D.  References

Channel Hardware Store.  1989 (August 14).  Fairfax, VA.  Survey of
merchandise prices performed by Louis Gardner, ICF Incorporated.

Cohen, Arthur.  1987 (September).  Copper and Copper Alloy Tube and Pipe.
ASTM Standardization News.  pp.  54-59.

Concast Metal Products.  1989 (July 20).  M. Barber.  Pittsburgh, PA.
Transcribed telephone conversation with Louis Gardner, ICF Incorporated,
Fairfax, VA.

Copper Development Association.   1989 (July 21).   A Cohen.  Greenwich, CT.
Transcribed telephone conversation with Louis Gardner, ICF Incorporated,
Fairfax, VA.

EPA.  1989 (January).  U.S. Environmental Protection Agency.   Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Glaeser, WA.  1983 (October).  Wear Properties of Heavy Loaded Copper Base
Bearing Alloys.  Journal of Metals,  pp. 50;55.

Kirk-Othmer.  1978.  Encyclopedia of Chemical Technology.   John Wiley and Sorts
Publishing Co. Inc.  Volume 3, pp.  674-77.  Volume 7,  p. 45.

Nielsen, WD.  Undated.   Metallurgy of Copper Base Alloys.   Casting Engineering
& Foundry World.  Reprint.

Wall Street Journal.  1989 (July 27).   Commodity  Prices.

Wolfenden, A. and Wright, PK.  1979 (August).   Role of Lead in Free-Machining
Brass.  Metals Technology,  pp.  297-301.
                                    -  122  -

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IX.  CADMIUM-PLATED PRODUCTS




      A.  Overview of the Plating Industry




      Plating can be defined as the application of metallic coatings to




various items in order to provide the base material to which they are applied




with surface properties of the metal that is used as a coating.  Coatings




provide protection to plated materials by one of five methods:  by protecting




the substrate by setting up a favorable electrochemical potential, by forming




a protective, passive film in aqueous media, by coating the substrate with a




slow oxidizer that protects the substrate at high temperatures, by acting as a




barrier to corrosive agents (e.g., noble metals), and finally, by providing




wear resistance by forming compounds that are much harder than the unplated




substrate (Kirk-Othmer 1978).




             1.  Plating Technologies




             Several technologies are used to apply metallic coatings.  The




particular process that is used depends on the properties of the substrate and




coating material.  Electroplated coatings are formed by electrodeposition of




the coating  material on the substrate, usually in an aqueous solution in which




ions of the  coating material are dispersed.  The ions are applied to the




substrate material by providing electrical current to the solution (Kirk-




Othmer  1978).  Another process, diffusion coating, places the coating material




 (in the liquid, solid, or vapor phase) in physical contact with the substrate




at an  elevated temperature, thereby creating interdiffusion of the two




materials at the  surface  (Kirk-Othmer  1978).




       Sprayed coatings are applied to  materials which cannot be easily coated




by other means due  to  the  size, shape, or susceptibility to damage by heat.




 In addition, some  coatings can be applied by mechanical methods or liquid




 metal  cladding where  the  materials are brought into physical contact by force





                                    - 123 -

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to disrupt oxide films on the surface of each, thereby allowing a




metallurgical bond to form (Kirk-Othmer 1978).




      Chemical coating is an electroless plating technique which involves a




catalytic chemical reaction reducing a species to a metallic or compound




material which forms the coating.  These reactions are temperature dependent




and can require temperatures from 500 to 1500"C.  Future development may allow




these reactions to take place at lower temperatures.  Finally, vacuum coatings




transfer the coating metal in the vapor phase through heat or a ballistic




process to the substrate.  The use of vacuum allows this process to take place




without interference from contaminating materials (Kirk-Othmer 1978).




            2.   Cadmium Plating




            Cadmium plating is used on fabricated steel and cast iron parts




and can be electroplated on plastics or metal in some appliance and consumer




applications.  Cadmium is used because it has a combination of properties:




natural lubricity,  corrosion resistance to salt water and alkalis,  high




deposition rate in application,  good solderability and ductility,  and a long-




lasting silvery-white luster (Kirk-Othmer 1978,  Humphreys 1989).




      Cadmium plating is used to protect bolts and screws used in marine




applications from corrosion due to prolonged exposure to moisture and salt.




In general, cadmium plated products have a longer service life due  to their




corrosion resistance and natural lubricity which helps in applications where




mechanical seizures would impair function.   Automotive uses such as seat belt




fasteners and brake linings are examples of applications for which  these




features are important (Cadmium Council 1989).   Cadmium plated fasteners also




are used because their natural lubricity reduces the torque experienced during




fastening which could cause fatigue (Humphreys 1989).
                                    -  124  -

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      B.  Consumption of Cadmium in Electroplating




      General use of cadmium plating has declined for two reasons:  1)  the




toxicity of cadmium itself and 2) cadmium traditionally has been plated on




surfaces using a cyanide bath which manufacturers also avoid because of health




and disposal problems.  However, newer solutions involving trivalent chromium




are being developed and have helped to revive to a certain extent cadmium's




use in plating (Humphreys 1989).




      The disposal of cadmium plated products in MSW will continue to decline




over the next few years because users have substituted for these products (EPA




1989).  The bulk of the remaining applications for cadmium plating are in the




automotive, aerospace, and military markets that are disposed in solid waste




facilities other than MSW.  In general, there has been a decrease in the




disposal of cadmium plated articles including dishwashers, washing machines,




radios, and televisions in MSW because substitutes are currently in place for




cadmium-plated parts in these applications.  Table 39 shows the discards of




cadmium in plated parts for home appliances and electronics for the period




between 1970 and 1986.  Due to the changes in materials that have already




occurred the total discards to MSW of cadmium in plated products in the year




2000 are anticipated to be only 29 tons (EPA 1989).




      C.  Potential Substitutes for Cadmium in Metallic Coatings




      Potential substitutes for cadmium in plating operations can be




classified into two groups:  alternative materials and technologies which do




not require the properties imparted by cadmium plating and alternative




coatings with similar properties that can be used in place of cadmium.




      The substitution which has already taken place in the majority of




household applications has used alternative materials.  Cadmium in washing
                                    -  125  -

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           Table 39.  Discards of Cadmium in Plated Parts for
                 Home Appliances and Electronics in MSV
            Discards in             Discards in          Total Discards
         Major Appliances*     Consumer Electronicsb         in MSW
Year          (tons)                   (tons)                  (tons)
1970
1975
1980
1986
47
39
32
24
571
330
176
161
618
369
208
185
Note:  Total discards of cadmium plated parts in MSW are expected to be
       29 tons in year 20'00.

• Assumes 8 year lifetime for appliances and includes adjustment for
cadmium recovered with ferrous parts.

b Assumes 8 year lifetime for products and includes an adjustment
for  imports and exports.

Source:  EPA 1989.
                                 - 126 -

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machines and dishwashers has been largely replaced by the increased use of




plastics which do not require cadmium plated bolts to hold the frames




together.  Similarly, the technology that used cadmium plated chassis in




radios and televisions is obsolete.  Steel chassis that were plated with




cadmium have been replaced by printed circuit boards made of resinous




materials (EPA 1989).




     Additional substitution for cadmium plating may use similar technology




changes or alternative coatings.  The choice of replacement plating will




depend upon which properties of cadmium coating are most important.  Although




inferior in terms of solderability and lubrication, zinc is already used




whenever possible because of reduced health and environmental concerns (Ajax




Metal Processing 1989).  Electroplated tin and gold are readily solderable,




although gold is very expensive.  Tin is not effective in corrosion




resistance, but the development of tin-zinc alloys and a zinc-nickel alloy as




possible substitutes for cadmium is progressing (AESF 1989,  Kirk-Othmer 1978).




Chromizing also is an economical process to improve corrosion resistance of




steel where appearance is not important.  Chrome offers the advantage of a low




friction surface and good wearability (Kirk-Othmer 1978),  but does not offer




the same corrosion resistance as cadmium.  Table 40 identifies the




characteristics of potential substitute plating technologies and alternate




products that can or have replaced cadmium plated parts in many applications.




Table 41 provides representative costs for these potential substitutes.




     As the tables indicate, there is a trade-off between cost,




processability, and corrosion resistance for plating technologies that replace




cadmium plating.  For most applications that enter MSW,  however,  a workable




substitute is available or can be developed.  In cases when alternate




materials (e.g., plastics) offer superior performance or wear characteristics





                                    -  127  -

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    Table  40.   Characteristics  of Potential  Substitutes  for Cadmium Plating
Use
Potential
Substitute
Advantages
Disadvantages
Electronics
(Chassis)
Fasteners
(Nuts, Bolts)
•  Resinous
   printed
   circuit
   boards
•  Plastic
   construction
                     •  Zinc plating
                     •  Tin plating
                     •  Gold plating
                     •  Chrome
                        plating
•  Already
   occurred;
   superior
   technology
•  Already
   occurred in
   consumer
   household
   appliances

•  Already
   preferred
   option where
   possible
                     •  Good solder-
                        ability
                     •  Good
                        corrosion
                        resistance
                        Good wear
                        properties

                        Better
                        corrosion
                        resistance
                        for acids
   Not possible
   in most
   cases
•  Lower
   corrosion
   resistance

•  Loss of
   lubricity

•  Loss of
   solder-
   ability

•  Poor
   corrosion
   resistance

•  Very
   expens ive

•  Poor wear
   resistance

•  Lower
   corrosion
   resistance
   for salts
   and neutral
   pH
Sources:  AESF 1989, Cadmium Council 1989,  Iron Age 1980,  Kirk-Othmer 1978.
                                    - 128  -

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Table 41.  Costs of Cadmium Plating and Potential Substitutes
                       Cost/lb.  of
                    Plating Material'
Relative Cost
 of Plating
 Compared to
  Cadmium15
Cadmium
Zinc
Tin
Gold
Chrome
$
$
$
$6,
$
4.50
0.80
5.60
552.00
7.50
1.00
0.50
1.05
1,500.00
1.12
        a Weights are all for standard avoirdupois
        pounds.

        b Relative cost are different from ratio of
        metal costs  due  to  overhead  and  different
        thickness requirements.

        Source:  Cadmium Council  1989, Ajax Metal
                Processing 1989, Kirk-Othmer  1978,
                Wall Street Journal 1989.
                           - 129 -

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to cadmium plating, substitution has already occurred to a large extent.  It




is also conceivable that these alternative materials can replace other




cadmium-based products that are still in use (e.g.,  plastic bolts in marine




applications that do not require high shear strength are possible).
                                   - 130 -

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      D.  References

Ajax Metal Processing.  1989 (July 27).  F. Buono.  Detroit, MI.  Transcribed
telephone conversation with Louis Gardner, ICF Incorporated, Fairfax, VA.

AESF.  1989 (July 31).  American Electroplaters and Surface Finishers Society.
W. Safranek.  Orlando, FL.  Transcribed telephone conversation with Louis
Gardner, ICF Incorporated, Fairfax, VA.

Cadmium Council.  1989 (July 27).  H. Murrow.  New York, NY.  Transcribed
telephone conversation with Louis Gardner, ICF Incorporated Fairfax, VA.

EPA.  1989 (January).  U.S. Environmental Protection Agency.  Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

Humphreys, PG.  1989  (May).  New Line Plates Non-Cyanide Cadmium.  Products
Finishing,  pp. 80-90.

Iron Age.  1980 (January  14).  Cadmium's Plight Opens Field to Alternative
Coatings,  p. 50.

Kirk-Othmer.  1978.   Encyclopedia of Chemical Technology.  John Wiley and Sons
Publishing Co., Inc.  Volume 6, p. 166; Volume 8, pp. 827-869.  1981.  Volume
15, pp. 241-274.

Wall Street Journal.  1989 (July 27).  Commodity Prices.
                                    - 131 -

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X.  COLLAPSIBLE TUBES




      A.  Overview of the Tube Industry




      Collapsible Cubes are used to dispense a number of products  from




medicines to epoxy resin adhesives.  While tubes are manufactured  from  a




variety of materials, lead tubes are used to dispense corrosive products  (lead




is difficult to corrode) or to satisfy customer packaging preferences



(Teledyne 1989).




      B.  Use of Lead Tubes




      Only a few companies still make lead tubes, including Teledyne Packaging




in Pennsylvania and Atlantic in New Jersey.  Lead tubes represent  a very  small




fraction (less than one percent) of the tube market (TCNA 1989a, 1989b).  Of




the lead tubes currently manufactured, most'are used for artists colors and




the remainder for corrosive glues.   Market surveys show that artists tend to




prefer the relatively heavy lead tubes because of the heft and quality feel




that is added to the paint product (Teledyne 1989).




      C.  Consumption of Lead in Tubes




      The consumption of lead in collapsible tubes reached a peak in 1969 and




has since declined (see Table 42).   The decline is attributable to the




increasing use of aluminum for this purpose (EPA 1989).   The total discards of




lead in tubes in MSW has dropped from over 9,000 tons in 1970 to about 600



tons in 1985 (EPA 1989).




      D.  Potential Substitutes for Lead Tubes




      The possible substitutes for lead tubes and their  performance




characteristics and relative price compared to lead  are  provided in Table  43.




One of the possible substitutes for lead tubes identified in the table  is




aluminum tubes with phenolic epoxy lining.   This aluminum technology does  not




differ in cost and offers similar performance to the lead tubes.





                                   - 132 -

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Table 42.  Discards of Lead in Collapsible Tubes in MSW
                       Discards of Lead in
                       Collapsible Tubes*
              Year           (tons)
              1970           9,310

              1975           2,860

              1980           1,477

              1986             639
              • The  lifetime  of  lead
              collapsible tubes  before
              discard is assumed to be
              2 years.

              Source:  EPA 1989.
                         -  133 -

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         Table 43.   Potential  Substitutes  for Collapsible  Lead Tubes
Lead Technology
Substitutes
Comments
Lead Tubes
•  Aluminum tubes with
   phenolic epoxy
   lining

•  Laminate tubes of
   plastic and
   aluminum
•  Similar in cost and
   performance to lead
   tubes

•  Similar in cost and
   performance to lead
   tubes
Source:  Teledyne 1989,
                                    - 134  -

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      The other substitute technology, laminate tubes manufactured with




alternating layers of plastic and aluminum also can replace lead tubes.




Unlike plain plastic tubes that have memory and return to their original




shape, laminate tubes will flatten during use.  Laminate tubes and lead tubes




are similar in cost (Teledyne 1989).
                                    -  135 -

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      E.  References                                 »

EPA.  1989 (January).  U.S. Environmental Protection Agency.  Characterization
of Products Containing Led and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.  Prepared by Franklin Associates Ltd., Prairie Village, KS.

TCNA.  1989a (May 31).  Klein, T.  Executive Secretary, Tube Council of North
America.  New York, NY.  Transcribed telephone conversation with Thomas Hok,
ICF Incorporated, Fairfax, VA.

TCNA.  1989b (August 15).  McCoy.  Assistant to the Executive Secretary, Tube
Council of North America.  New York, NY.   Transcribed telephone conversation
with Thomas Hok, ICF Incorporated, Fairfax, VA.

Teledyne Packaging.  1989 (May 31).  K. Barry  .  New Jersey.  Transcribed
telephone conversation with Thomas Hok, ICF Incorporated, Fairfax, VA.
                                    -  136  -

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XI.  OTHER PRODUCTS

      There are a variety of  other products  that  contain  lead  and/or  cadmium

and are disposed in MSW  facilities.  These products account  for a very  small

percent of the total amount disposed, but are discussed in this chapter for

completeness.  The products are:

            •     Foil wine wrappers;
            •     Used oil;
            •     Rubber (elastomers); and
            •     Electric blankets/heating pads.


      A.  Foil Wine Wrappers

      The capsule used to enclose the cork in a wine bottle contains a  tin-

lead alloy.  The Wine Institute (1989) reports that a tin-lead capsule has

traditionally been used for market recognition and that plastic would be a

viable substitute (EPA 1989) .   In addition,  some liquor products use aluminum

foil as wrappers.   Lead wrappers are easily substituted because the cost of

substitute plastic and aluminum foil wrappers are comparable to that of lead

wrappers,  and wrappers do not constitute a significant portion of the cost of

a bottle of wine,  but consumers seem to prefer the lead wrappers because of

the appearance of quality that the lead wrapper imparts to the bottle (Wine

Institute 1989).   The discards of lead for this use are presented in Table 44.

      B.  Used Oil

      The used oil generated by the do-it-yourself (DIY)  automobile  sector is

the main source of oil waste entering the MSW.   Although the  sources of  lead,

and, to a lesser extent,  cadmium in used oil  include the  particles  of metal

from engine wear and derivatives of gasoline  combustion,  this analysis is

concerned with the amount of lead contained  in the oil before it is  used
                                    - 137 -

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    Table 44.   Discards of Lead in Foil Wine Wrappers in MSW
Year
1970
1975
1980
1986
Lead Foil on
Domestic Wine Bottles*
(tons)
552
321
311
181
Lead Foil on
Imported Winesb
(tons)
39
35
72
22
Total Foil
Discarded0
(tons)
591
356
383
202
8 Assumes to be 10 percent of total domestic lead foil
consumption.

b Estimate based on the ratio of domestic to imported wine
purchases for the given year, assuming that all imported
wines use lead foil wrap.

c Assumes all foil discarded in the year of production.

Source:  EPA 1989.
                             -  138 -

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because it would not be feasible to address  the lead and cadmium  that  is




deposited in oil from other sources given the scope of this analysis.




      Organic leaded compounds are used in oil and lubricant additives as




antiwear agents.  Antiwear agents produce a  surface film to minimize friction




and wear under boundary-lubrication conditions.  The role of cadmium in




lubricant additives in used oil is very small compared to that of lead.




Cadmium discards are, therefore, not discussed in this report.




      The disposal in MSW of lead in oil and gasoline additives dropped




dramatically over the period 1970 to 1986:   from over 1,600 tons in 1970 to




just under 200 tons in 1986.  Recycling of used oil and reduction of lead




content have been responsible for this decline.  Table 45 presents the




consumption of Lead in used oil that is disposed of in MSW.




      A large number of formulations are available that can perform the role




of anti-knock agents and improve lubrication in oil products.   Potential




substitutes include iron and zinc organo-phosphates,  iron and zinc chlorides,




and iron sulfides.   These products are comparable in price to the lead-based




compounds and have essentially the same performance characteristics.   Table 46




presents the information on potential substitutes for alkyl  lead compounds




used in oil products.




      C.  Rubber (Elastomer) Products




      Rubber products are usually modified by processing with vulcanizing




agents and other additives before they can be used in most applications.  Lead




and cadmium compounds are found in a number of these  rubber  compounding




chemicals including:  pigments,  fillers,  activators,  vulcanizers  or  curing




agents, stabilizers, and plasticizers.   Lead metal may also  be  integrated into




a rubber product such as lead-sheathed hose (EPA 1989).
                                    -  139  -

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          Table  45.   Discards  of Lead in Used Oil  in MSW
Year
1970
1975
1980
1986
Estimated Used
Oil in MSW
(tons)
556,257
661,900
673,935
708,772
Average Lead
in Used Oil
(ppm)
2,889
1,606
1,265
268
Net MSW
Discards of Lead
(tons)
1,636
1,261
853
190"
Note: Less than 1 ton of cadmium is expected to be disposed
      annually in municipal solid waste.   This is based on a
      median concentration of 1.4 ppm cadmium (EPA 1989).

a Discards were expected to be about 74  tons in 1988.

Source:  EPA 1989.
                              -  140 -

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          Table 46.  Potential Substitutes for Alkyl Lead Anti-Knock
                        Agents Used  as  Oil  Lubricants
Lead Products
Potential Substitute Products
Alkyl Lead Compounds
•  Iron and zinc organophosphates

•  Iron and zinc chlorides

•  Iron sulfides
Source:  Kirk-Othmer 1983.
                                    -  141 -

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      These products can be broken down  into three main  types  of  ingredients

used for rubber compounding:  cure systems, protective systems, and pigments.

Cure systems include activators, vulcanizers or curing agents, stabilizers,

and platicizers.  Protective systems include fillers and other chemical

additives.

      Pigments may be used in elastomers for color identification of two

similar objects, to improve aesthetic appeal, or to match two parts of

different composition with the same color.  Examples of these uses include

coloring white walls on tires,  backing on carpeting, sporting goods such as

basketballs, rubber bands, rubber-based floor tile, housewares, and clothing

and footwear (Pigment Handbook 1973).

      Lead compounds used as activators and vulcanizers in rubber include

litharge (lead oxide),  lead peroxide, and lead stearate.   Accelerators and

activators may employ inorganic compounds such as lead oxide, red oxide,  and

white lead (EPA 1978).   Lead dimethyl dithiocarbamate,  a vulcanizing agent, is

used in the base compound for V-belt* manufacture.

      Discards in MSW of lead and cadmium in rubber products are  presented in

Tables 47 and 48.   The  total input to MSW identified in the  EPA (1989)  report

for rubber products is  considered to be the lead and cadmium pigments  used in

rubber.   The other lead- and cadmium-containing products  in  rubber are  assumed

not to enter MSW (EPA 1989).

      Lead and cadmium are among the least common chemicals  used  during rubber

formulation, but both metals may be used in dithiocarbamate  compounds  as

vulcanizers or curing agents.   Cadmium acts as  an accelerator during the
       V-belts and other shaped belts  are used  in automobile and other engines
to transfer energy from one moving part to  another.   "V"  refers  to  the
trapezoidal cross section shape which makes the belt  hold in place  better.
                                   - 142 -

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Table 47.  Discards of Lead in Pigments Used in Rubber Products in MSW
  Year
 Discards of
   Lead in
Tire Pigments
   (tons)
   Discards of
Lead in Fabricated
 Rubber Products
      (tons)
 Total Discards
   of Lead in
Rubber Pigments'
     (tons)
1970
1975
1980
1986
45
44
83
56
16
15
33
21
52
53
104
70
  • Ten to fifteen percent of tires and other rubber products are
  diverted or recovered annually.

  Source:  EPA 1989.
                                - 143 -

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Table 48.  Discards of Cadmium Pigments
     Used in Rubber  Products  in MSW
              Cadmium  in  Pigments
              for Rubber  Products'
    Year            (tons)
     1970               10

     1975               13

     1980               8

     1986               6
    * Consumption of cadmium pig-
    ments  in rubber was assumed  to
    be one percent of total con-
    sumption of cadmium pigments.

    Source:  EPA 1989.
                -  144 -

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curing process, decreasing energy requirements (Gates Rubber 1989).  While

other compounds in the dithiocarbamate family may be substituted for lead and

cadmium dithiocarbamate compounds, some changes in the performance of the

final rubber products may occur (Polysar 1989).  The use of cadmium in rubber

products improves aging resistance by decreasing the likelihood of hardening

at high temperatures, but neither cadmium nor lead vulcanizing agents are

required for rubber formulation.  Zinc dithiocarbamates not only provide an

acceptable chemical substitute for cadmium and lead dithiocarbamates, but zinc

compounds are also less costly.*  Table 49 presents potential substitutes for

lead and cadmium vulcanizing agents;  discussion of potential substitutes for

pigments can be found in the chapter on plastics (Chapter II).

      Lead and cadmium also may be considered part of the protective system of

a rubber compound.  Cadmium accelerators tend to improve the aging resistance

of rubber, and lead increases the density and strength of rubber used for

hydraulic lines (Gates Rubber 1989).  Lead lubricants also help the rubber

release from commonly used lead molds.  However, lead and cadmium are not

essential to protective systems in rubber compounding (Polysar 1989).

      D.  Printing Inks

      Printing inks that are disposed in MSW primarily are used for printing

newspapers, magazines, and packaging for a variety of consumer products.

These inks consist of a dissolved dye or pigment in a vehicle to produce a

fluid or paste that can be transferred to paper, film, foil, or metal.   The

solvent then evaporates, leaving the ink on the surface.
      * Although their use is not essential, lead and cadmium may still be used
 in rubber  compounds because of compatibility, customer preference, or price
 considerations.

                                    - 145 -

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         Table  49.   Potential Substitutes  for Representative Lead- and
                       Cadmium-based Vulcanizing Agents
Lead and Cadmium            Substitute                  Other Compounds
Compounds                   Dithiocarbamates


Lead dithiocarbamate        Bismuth                     Aldehyde -amine
                                                        reaction products
Cadmium                     Copper
dithiocarbamate                                         Benzothiazoles
                            Selenium
                                                        Benzothiazolesul-
                            Tellurium                   fenamides
                                                        ''*.
                            Zinc                        Dithiophosphates

                            Piperidinium                Guanidines

                            Thiazoles                   Thioureas

                                                        Thiurams

                                                        Thiocarbamyl
                                                        sulfenamides

                                                        Other curing agents*


Note: These potential substitutes are presented for completeness even though
      this analysis assumes that the total lead and cadmium contribution to
      MSW from rubber products is attributable to pigments (EPA 1989).

* Other curing agents include alkylphenol-formaldehyde  resin,  alkylphenol
disulfides, N,N'-caprolactam disulfide, p-quinonebis(benzoyloxime),  4,4'-
dithiobismorpholine, hexamethylene diamine carbamate,  p-quinone dioxime,
sulfur, and insoluble sulfur.

Sources:  Kirk-Othmer 1983.
                                    .  146  -

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      Printing inks may be classified as organic or inorganic.  While both

categories of ink may contain trace elements, inorganic inks contain the

highest levels of lead or cadmium.  Organic  inks may contain trace amounts of

lead and cadmium as impurities  (BASF 1989, EPA 1989).  Cadmium  is not widely

used for inorganic printing inks; cadmium pigments are very lightfast and tend

to be used in automobile manufacturing* or for printing applications that

demand the pigment withstand chemicals  (e.g., a label for an acid bottle) (ICI

1989, ANPA 1989b).  Cadmium inks  are heavy and do not tend to flow well  (ANPA

1989b).  Printing inks that contain lead are inorganic and include lead

chromate (yellow and orange) and  molybdate orange (ANPA 1989b).  Neither lead

nor cadmium are used to make black ink, or in lithographic printing  (used to

produce magazines)  (ANPA 1989a, 1989b,  1989c).

      Relatively little lead is currently used in printing inks.  As shown inr

Table 50, discards  of lead in printing  ink has declined steadily and

substantially since 1970.  The  amount of ink discarded in 1970  is over 72

times the amount discarded in 1986.  This decline in lead use reflects the

general  trend away  from inorganic pigments toward organic pigments.  While

some printing applications  (e.g., covering a dark background with a light

color and clear  films used  in packaging) may demand the use of  inorganic

pigments  for  their  excellent opacity  (hiding power) and brightness, recently

developed organic pigments  also have very good opacity, color,  and brightness

 (BASF  1989, ANPA 1989b).

       Dialyrid  yellow and dialyrid  orange are the major substitutes for  lead-

 containing  printing inks.   These  substitute  inks are used in newspapers,

 magazines,  and  packaging.   Table  51  shows  the advantages and disadvantages of
      * BASF,  a major U.S.  ink manufacturer,  does not use cadmium  in any of its
 inks (Wagner 1989).

                                     -  147  -

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         Table 50.   Discards of Lead in Printing Inks in MSW
                              Lead Discards in
                               Printing Inks8
                     Year          (tons)
                     1970          19,192

                     1975          13,819

                     1980           8,222

                     1986             265
a Lead in ink is assumed to enter MSW in the same year as it is
consumed.  Adjustments were made to reflect the industrial disposal
of ink that is removed from recycled paper.  Manufacturing losses
were estimated to be 5 percent.

Source:  EPA 1989.
                               - 148 -

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   Table 51.   Advantages and Disadvantages of Potential Substitute Ink Pigments
                    for Lead-containing Printing Ink Pigments
Lead-Containing
Ink Pigment
Potential
Substitute
Pigment
Advantages
Disadvantages
Lead Chromate
(yellow or
orange)
Dialyrid Yellow
• Does not
  contain lead
Molybdate
Orange
Dialyrid Orange
• Does not
  contain lead
• More expensive
  than lead
  chromate and
  lead sulfo-
  chromate

• Less lightfast
  and opaque than
  lead chromate
  and lead sulfo-
  chromate

• More expensive
  than lead
  chromate and
  lead sulfo-
  chromate

• Less lightfast
  and opaque than
  lead chromate
  and lead sulfo-
  chromate
 Sources:   BASF 1989,  ANPA 1989a,  1989b.
                                     - 149 -

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the potential substitute  inks.  While  lead-containing  inks have  better

lightfastness and opacity, the organic substitutes perform well  and  are

constantly improved through research.*

      The opacity of the  potential substitute inks can be increased  by either

adding titanium dioxide to thicken the ink, or by "sizing" the printing

surface.**  The  addition of titanium  oxide  tends  to wash  out  the  color of an

ink if enough titanium oxide is added to create good opacity.  Dialyrid yellow

and dialyrid orange are more expensive than lead chromate and molybdate orange

(BASF 1989,  ICI 1989,  ANPA 1989b).

      E.   Electric Blankets and Heating Pads

      Cadmium-containing  copper wire has been used in electric blankets and

heating pads.   This use has not been characterized and potential substitutes

have not been evaluated because of the extremely low discard volume.   It is

likely,  however, that other copper alloy wires will be able to fully supplant

the cadmium-containing wires.   Table 52 presents the  discards in MSW of

cadmium wire  for electric blankets  and heating pads.
       The  American Newspaper  Publishers Association  (ANPA) produces lead-free
ink (trace amounts of lead and cadmium impurities  are found in all  ink
formulations as a processing by-product);  97 percent  of all newspapers
published in the U.S. use ANPA inks (BASF  1989).

        "Sizing" a  surface means precoating  it before the application of ink
such that the ink will provide more even and opaque coverage  of the surface.

                                    - 150 -

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Table 52.  Discards of Cadmium in Electric Blankets in MSW
Year
1970
1975
1980
1986
Cadmium Discards
(tons)
1
1
1
1
              • Assumes a product lifetime
              of 8 years.

              Source:  EPA 1989.
                          - 151 -

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      F.  References

ANPA.   1989a  (August  14).  G. Cashau, Director of Technical Research,  American
Newspaper Publishers  Association, Reston, VA.  Transcribed telephone
conversation with Thomas R. Hok, ICF Incorporated, Fairfax, VA.

ANPA.   1989b  (August  14).  P. Volpe, Technical Coordinator, National
Association of Printing Ink Manufacturers, Westchester, NY.  Transcribed
telephone conversation with Thomas Hok, ICF Incorporated, Fairfax, VA.

ANPA.   1989c  (August  30).  G. Cashau, Director of Technical Research,  American
Newspaper Publishers  Association, Reston, VA.  Transcribed telephone
conversation with Louis Gardner, ICF Incorporated, Fairfax, VA.

BASF.   1989 (August 14).  R. Wagner, Manager in Charge of Product Compliance,
BASF, Clifton, NJ.  Transcribed telephone conversation with Thomas Hok, ICF
Incorporated,  Fairfax, VA.

EPA.  1978.   U.S. Environmental Protection Agency.  Assessment of Industrial
Hazardous Waste Practices -- Rubber and Plastics Industry, Rubber Products
Industry.

EPA.  1989 (January).   U.S.  Environmental Protection Agency.   Characterization
of Products Containing Lead and Cadmium in Municipal Solid Waste Facilities
1970 to 2000.   Prepared by Franklin Associates Ltd.,  Prairie  Village,  KS.

Gates Rubber.   1989 (June 1).   E.  Karger.   Denver,  CO.   Transcribed telephone
conversation with Thomas Hok,  ICF Incorporated,  Fairfax,  VA.

ICI.  1989 (August 3).  J.  Klein,  Lab Manager,  ICI Americas Incorporated,
Wilmington,  DE.   Transcribed telephone conversation with Thomas Hok,  ICF
Incorporated,  Fairfax, VA.

Kirk-Othmer.   1983.   Encyclopedia of Chemical Technology.   John Wiley  and  Sons
Publishing Co.  Vol.  14, pp.  493-496;  Vol.  20,  p.  338.

Pigment Handbook.  1973.  Volume 3;  First Edition.

Polysar.  1989 (June 1).  J.  Dunn.   Polysar,  Canada.   Transcribed telephone
conversation with Thomas Hok,  ICF Incorporated,  Fairfax,  VA.12

Wine Institute.   1989  (June  1).   W.  Lee.   San Francisco,  CA.  Transcribed
telephone conversation with  Peter Weisberg,  ICF  Incorporated, Fairfax,  VA.
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