EPA
United States
Environmental Protection
Agency
Region 5
77 West Jackson Boulevard
Chicago, Illinois 60604
EPA 905-F-00-028
August 2000
TECHNICAL FACT
SHEET FOR
I
Cadmium is one of the
PBT chemicals
identified as a priority.
Cadmium is released
into the environment
through mining and
metal processing
operations, burning fuels, making and using
phosphate fertilizers, and disposing of metal
products. One of the reasons that cadmium has
been listed as a PBT is that inhaling cadmium
fumes at high exposures can cause heart and
lung irritation, including shortness of breath,
chest pain, coughing, and a buildup of fluid in
the lungs. Cadmium is considered to be toxic,
and is a probable cancer-causing agent in
humans. It is believed that cadmium can have
toxic effects on the prostate, kidney, lung and
testes, and may also affect the female
reproductive cycle.
CADMIUM
EPA PARTNERSHIP AND
YOU...
The United States Environmental Protection Agency
(EPA) has identified numerous persistent,
bioaccumulative and toxic (PBT) chemicals that may
be present in some industrial hazardous wastes regulated under the
Resource Conservation and Recovery Act (RCRA). In addition to its
ongoing regulatory activities, EPA will focus voluntary efforts on actions
that reduce the generation of these PBT chemicals. EPA will also work
with states, industry, and environmental groups through workshops,
technical assistance programs, partnership agreements, regulatory
reinvention projects, and other strategies to promote progress toward the
goal of reducing the generation of RCRA PBT's in hazardous waste by 50
percent by the year 2005.
THE CADMIUM CONNECTION
Even though cadmium is extremely toxic and regulated by the EPA, large
amounts of cadmium are still utilized in a range of applications by a variety
of industries. Because of its regulatory status and the higher costs of
^^^^_^___ cadmium, many industries are looking for less hazardous
alternatives. Most cadmium used in the United States is
a soft metal or powder obtained as a by-product from the
treatment of copper, lead and iron ores.
II
II
Here are just a few of the uses for cadmium:
Plating metal parts
Fertilizers
Plastic stabilizers
Batteries
Here are some of the industries that may use cadmium:
X Manufacturers of fabricated metal parts
X Manufacturers of plastics
X Manufacturers of paints and pigments
X Manufacturers of alloys, chemical reagents and/or
intermediates
X Manufacturers of fertilizer
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BREAKING THE TIE WITH CADMIUM
There are several different
alternatives and processes that are
available to eliminate or reduce the
amount of cadmium used in
manufacturing operations. When a
company decides to modify their process operations to
reduce or eliminate cadmium, the facility should evaluate
these different processes and test several applications to
determine what method would best fulfill its needs. Listed
below are several replacement or reduction alternatives for
cadmium:
Aluminum Ion Vapor Deposition System (AIVD}: The
ATVD system can be used in place of cadmium in the
electroplating industry. The maj or components of an AIVD
system are comprised of an IVD vacuum chamber, a
positive pressure clean room, a two-stage vacuum pump
system, a cryogenic cooler and a parts rack with air-
flotation transport dollies. By changing to an ATVD system,
no hazardous materials will be required in coating
operations and no hazardous waste will be generated.
Some other advantages by switching to an AIVD system
are that in acidic environments, AIVD prevents corrosion
better than cadmium coatings, ATVD coatings stand up to
higher temperatures and ATVD allows for a thicker and
more uniform coating on the parts. AIVD is a technology
that can replace cadmium in many different applications.
AIVD can be used to apply coatings of aluminum to metal,
plastic, composites and other substrates.
Reverse Osmosis and Closed Loop System: In
manufacturing operations where cadmium waste is
produced, a reverse osmosis filter system can be used to
filter out the cadmium from process wastewater. For
example, a company that used zinc metal powder, along
with cadmium chloride salt produced by-products of zinc
chloride and a cadmium powder. The cadmium powder
was removed by the reverse osmosis system, while the zinc
chloride was used for other production purposes. A
closed loop system was then installed which recycled the
wastewater produced and fed the water back into
production processes as clean-up water. One disadvantage
of reverse osmosis systems is the clogging of the filter
membrane with solid particles. Yet, this can be alleviated
in most cases by simply adjusting the pH of the water which
will hinder precipitation and therefore eliminate the solids
from obstructing the filter.
Non-Cadmium Based Pigments: Many types of
cadmium-free pigments are available today for use in
industry. One example of a cadmium-free pigment was
created by combining an alloy of polycarbonate and
acrylonitrile-butadiene styrene terpolymer (ABS). The new
cadmium-free formula passed a 1000-hour UV-ray
exposure test, equivalent to three years' exposure to the
sun. By switching to cadmium-free pigments, it may also be
possible to reclassify the waste stream as non-hazardous,
depending on the alternative used.
Zinc-based Replacements: A variety of zinc-based
chemistries can be substituted for cadmium in the
electroplating industry. A few of the more common zinc-
based alternatives that may be used to replace cadmium are
described in more detail below.
*• Zinc-Nickel Alkaline: This alternative provides good
corrosion properties after parts-forming operations
and heat treating and produces uniform thickness
during coating processes, but a chiller is required to
maintain optimum temperature conditions. This
substitute produces a deposit that tends to favor
applications that do not require bend-ability.
* Zinc-Cobalt Acid: The plating bath for this
alternative has a high cathode efficiency and a high
plating speed, but has variable current density.
Tin-based Replacements: There are also a several of tin-
based electroplating options available to replace cadmium.
A few of the more common tin-based substitutes are
described below in more detail.
*• Tin-Nickel Acid or Near Neutral: This option has
a good resistance to corrosion and tarnish and also
has good ductility. The finish on the coated
materials can also be very decorating in
appearance.
*• Tin-Zinc Acid. Alkaline or Neutral: The tin-zinc
alternatives have good
corrosion protection
with chromate applied
and do not undergo
bimetallic corrosion.
The finish has a fair appearance, yet with excellent
ductility.
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MEASURE YOUR SUCCESS
Many companies have benefitted by
replacing cadmium in their process or
product, and simply using the available
environmentally friendly alternatives or
recycling and reusing cadmium in
production processes. Here are some stories for several
companies that have successfully implemented cadmium-
reduction methods in their operations:
> A manufacturer that produces batteries was creating
significant amounts of cadmium powder as a by-
product (along with other metals) in production
processes. By installing a reverse osmosis
membrane system in place of the heat treatment
system, the metals can be recovered and reused
instead of discharged with wastewater. The capital
cost for this equipment was under $50,000 and the
payback period was approximately six months.
> A metals processing company installed an electro-
winning unit on their electroplating line due to
dragout contributing to high metals contamination in
wastewater. The results were lower water use,
zero discharge to the wastewater treatment system
and filter cake disposal with no adverse impacts on
product quality. The capital cost for this unit was
$9,000 with a savings of over $1,500 per year.
> Another plating company eliminated cadmium and
substituted a zinc-cobalt solution in its operations.
Changing solutions did not require any additional
equipment, but eliminated an entire process from
waste treatment operations. The estimated savings
for this company was $35,000 per year.
> An Army Depot installed aluminum iron vapor
deposition equipment in their facility to assist in the
reduction of the amount of cadmium used during
plating processes. The project reduced cadmium by
over 50 percent and would, in time, increase that to
80 percent. The system also reduced the
generation of hazardous waste by over 4,300 pounds
per year. The equipment cost was $848,000, but the
first year of savings in operational costs was over
$1,000,000.
> A company discontinued the use of cadmium-based
pigments by substituting a non-cadmium based
pigment in its process operations. By doing so, this
company was able to reclassify their waste stream
as a non-hazardous waste which then eliminated
approximately 38,000 pounds of waste per year,
with an estimated annual savings of $10,000.
FOR MORE INFORMATION...
There are various resources to locate
more information on the substitution and
potential elimination of cadmium from your
workplace. Here a just a few of the Web
sites available via the Internet and the
government agency listings that would be able to provide
more information.
Web sites
us- www.epa.gov/osw/index.htm
83° .es.epa.gov/program/regional/state/wi/rayovac.html
(Envirosense)
us- www.oznet.ksu.edu/dp _nrgy/ppi/publications/manual/
MetalFinish/sectionS .html
83° nuclear.hazard.uiuc.edu/packets/finishing/plating.htm
83° p2.utep.edu/casestudies/corparml95.htm
us- www.elna-america.com/DLC-battery.htm
us- www.goldenpaints.com/cadmiums.htm
83° aec. army, mil: 8080/prod/usaec/et/pp/ion. htm
83° www.epa.gov/iris/subst/0141.htm
83° www. aaplating. com/ivd-info-envir.htm
83° es.epa.gov/techinfo/facts/epa/metlfnsh.htm(Envirosense)
83° www.nsc.org/ehc/ew/chems/cadmium.htm
BS° www.globar.com/maxcap.html
»3° www.epa.state.oh.us/opp/gov/factl7.html
83° www.pwrc.usgs.gov/new/chrback.htm
Government Listings
-PIK-P2P2)
U.S. EPA Region 5
P2 Hotline
=0 888/745-7272
Illinois Environmental Protection Agency
Office of Pollution Prevention
=0 217/782-8700
Indiana Dept. of Environmental Mgmt.
Office of Pollution Prevention
=0 317/232-8172
Michigan Dept. of Environmental Quality
Environmental Assistance Division
=0 800/662-9278
Minnesota Technical Assistance Program
=0 612/624-1300
Ohio Environmental Protection Agency
Office of Pollution Prevention
=0 614/644-3469
Wisconsin Dept. of Natural Resources
Cooperative Environ. Assistance
=0 608/267-9700
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United States Environmental Protection Agency
Region 5
Waste, Pesticides, and Toxics - WMB - DW-8J
77 West Jackson Boulevard
Chicago, Illinois 60604
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