United States Environmental Protection Agency
         Office of Wastewater Management
         Washington, DC 20460
Environmentally Acceptable
                                EPA 800-R-11-002
                                November 2011

Exhaust Gas Scrubber Washwater Effluent                                              Contents
      1.1    Marketing and Labeling	3

      2.1    Vegetable Oils	4
      2.2    Synthetic Esters	4
      2.3    Polyalkylene Glycols	5
      2.4    Water	5

      3.1    Thickening Agents	6
      3.2    Advantages and Disadvantages of Vegetable-based EALs	6
      3.3    Advantages and Disadvantages of Synthetic Ester-based EALs	7
      3.4    Advantages and Disadvantages of Polyalkylene Gly col-Based EALs	8
      3.5    Availability and Cost of EALs	8

      4.1    Biodegradability	10
      4.2    Aquatic Toxicity	11
      4.3    Bioaccumulation	13
      4.4    Summary of Environmentally Acceptable Lubricant Characteristics	14

      5.1    National Labeling Programs	16
             5.1.1  Blue Angel	16
             5.1.2  Swedish Standard	16
      5.2    International Labeling Programs	17
             5.2.1  Nordic Swan	17
             5.2.2  European Eco-label	17
             5.2.3  OSPAR	19
      5.3    Summary of Environmentally Acceptable Lubricant Labeling Programs	19


7     REFERENCES	7-22

Environmentally Acceptable Lubricants
                                 LIST OF TABLES
1     CostofEALs	9
2     Internationally Standardized Test Methods for Measuring Biodegradability	11
3     Summary of Differential Biodegradation Rates by Lubricant Base Oils	11
4     OECD Aquatic Toxicity Tests	12
5     Summary of Comparative Toxicity of Base Oils	12
6     Summary of Bioaccumulation Potential by Base Oil Types	14
7     Comparative Environmental Behavior of Lubricants by Base Oil Type	15
8     Comparison of EAL Labeling Programs	20

                                 LIST OF FIGURES
1     Annual Oil Inputs into the Marine Environment	2
The EPA contacts for this document are Ryan Albert (202) 564-0763 and Brian Rappoli (202)

Environmentally Acceptable Lubricants                                         Section 1 - Introduction

                                                                         SECTION 1


       The purpose of this document is to describe the range of environmentally preferable
lubricants that may be used as a best management practice (BMP) by operators of vessels
covered under the Vessel General Permit for Discharges Incidental to the Normal Operation of
Vessels (VGP)1. Within this document, the term environmentally acceptable lubricant (EAL) is
used to describe those lubricants that have been demonstrated to meet standards for
biodegradability, toxicity and bioaccumulation potential that minimize their likely adverse
consequences in the aquatic environment, compared to conventional lubricants. In contrast,
lubricants that may be expected to have desirable environmental qualities, but have  not been
demonstrated to meet these standards, are referred to as environmentally friendly lubricants
(EFLs) or biolubricants.

       Lubricants lost from a vessel enter the aquatic environment, where serious damage to the
aquatic ecosystem can occur. Consequently, there has been an emphasis on encouraging the use
of EALs on vessels to protect the environment (Carter, 2009). Although their use is increasing,
EALs comprise only a small percentage of the total lubricant market.

       The significance of lubricant discharges (not accidental spills) to the aquatic ecosystem is
substantial. The majority of ocean going ships operate with oil-lubricated stern tubes and use
lubricating oils in a large number of applications in on-deck and underwater (submerged)
machinery. Oil leakage from stern tubes, once considered a part of normal "operational
consumption" of oil, has become an issue of concern and is now considered as oil pollution.
Stern tube leakage is a significant source of lubricant oil inputs to the aquatic environment. A
2001  study commissioned by the European Commission DG Joint Research Centre  revealed that
routine unauthorized operational discharges of oil from ships in the Mediterranean Sea created
more pollution than accidental  spills (Pavlakis et al., 2001). Stern tube leakage was  identified as
a major source of these discharges.

       An analysis of data on oil consumption performed by a lubricant supplier indicated a
range of average  daily stern tube lubricant consumption rates for different vessels (Etkin, 2010).
The average rate  across vessel types was 2.6 liters per day, but ranged from less than 1  liter per
day to 20 liters per day.  Because it is common practice to use the lubricant supplied for the
vessel's main engines as the stern tube lubricant to minimize the number of lubricants held on
board, the amount which is used in stern tubes and released to the sea is not recorded.

       Engine oil formulations have the correct characteristics (e.g., viscosity) to fulfill the role
of lubricants  specifically  formulated for stern tubes. However, engine oil additives,  which can be
up to 30% of the  formulation, are  strongly alkaline (to neutralize the acids formed during fuel
combustion). Consequently,  due to the nature  of engine oil additives, this practice greatly
increases the toxic effects of stern tube discharges.
1 The 2008 VGP encourages vessel owners and operators to use environmentally preferable lubricants whenever

Environmentally Acceptable Lubricants
                  Section 1 - Introduction
       In addition to spills and stern tube leakage, there are "operational inputs" of lubricant oils
that occur due to continuous low-level discharges and leakages that occur during normal vessel
operations in port. The sources of operational discharges include deck machinery and in-water
(submerged) machinery. There are a number of systems situated below the waterline that must be
lubricated. The main systems to consider are the stern tube bearing, thruster gearboxes, and
horizontal stabilizers. All of these have pressurized lubricating oil systems that maintain a
pressure higher than the surrounding sea. This ensures that no significant amount of seawater can
enter the oil system, where it would compromise the unit's reliability. However, any  leakage of
lubricant oil flows into the sea.

       A 2010 study estimated the marine inputs of lubricant oils within the 4,708 ports and
harbors of the world through stern tube leakage and operational discharges from marine shipping
(Etkin, 2010). The study results indicate that commercial vessels make over 1.7 million port
visits each year and leak 4.6 to 28.6 million liters of lubricating oil from stern tubes. In addition,
32.3 million liters of oil is introduced to marine waters from other operational  discharges and
leaks. In total, operational discharges (including stern tube leakage) input 36.9 to 61 million
liters of lubricating oil into marine port waters annually - the equivalent of about one and a half
Exxon Valdez-sized spills. Assuming that the higher estimate of stern tube leakage is
representative of the inputs that may occur in port as well as in transit, the total estimated input
of lubricating oil from leakage and operational discharges represents nearly 61 million liters
annually worldwide. Leaks of lubricating oil represent 10 percent of the total oil inputs into
marine waters, as estimated in the 2003 NRC Oil in the Sea study (see Figure 1). The total
annual estimated response and damage costs for these leaks and operational discharges are
estimated to be about $322 million worldwide. Total estimated costs for the U.S. are estimated to
be $31 million annually (Etkin, 2010).
Aircraft Fuel i
  L4H- VMS*] Spills
         U**  '
acility Spill:
                    Based on Etkin, 2010 and NRC, 2003

                 Figure 1. Annual Oil Inputs into the Marine Environment

       The following sections of this document describe the main types of EALs in current
production; considerations for EALs in the aquatic environment; the standards for
biodegradability, toxicity and bioaccumulation potential of EALs; the potential advantages and
disadvantages of using EALs on board commercial vessels; and labeling programs.

Environmentally Acceptable Lubricants                                        Section 1 - Introduction

       Although EALs have been in commercial production for years, they comprise a small
portion of the total lubricant market and are still regarded as niche products (Habereder et al.,
2008). The market for EALs continues to expand, particularly in Europe, where the use of such
lubricants is being encouraged through a combination of tax breaks, purchasing subsidies, and
national and international labeling programs based on well-defined criteria. Many lubricants are
advertised as being environmentally preferable; however, currently there are no regulatory
standards for EALs, and no internationally accepted term by which they are defined.  To
distinguish lubricants which have been shown to be both biodegradable and non-toxic according
to  acceptable test methods from those lubricants that are simply marketed as being
"environmental" (or similar terminology), in their 1999 Lubricants and Hydraulic Fluids Manual,
the US Army Corps of Engineers recommended use of the term "environmentally acceptable" (a
term commonly used by American Society for Testing and Materials (ASTM) committees) to
address environmental lubricants. Bioaccumulation potential was not addressed within this
definition of EALs.

       While numerous terms are presently used to advertise  lubricants as having desirable
environmental properties, there is growing consensus to use the term "environmentally
acceptable" to denote a lubricant that is biodegradable, exhibits low toxicity to aquatic organisms
and has a low potential  for bioaccumulation. Although many tests for these qualities  exist, there
is also harmonization underway within the lubricant manufacturing community regarding the
most appropriate standard testing methods for these and other qualities determined to be
important for an EAL, such as the proportion of renewable (recyclable) materials used in
manufacturing. An environmentally acceptable lubricant should still perform well in  comparison
to  the conventional lubricant it replaces. This harmonization is being driven by national and
international labeling programs, particularly in European nations where the testing procedures
and criteria have been codified (Habereder et al., 2008 and IENICA, 2004). These labeling
requirements, while not regulated by law, have helped to clarify the difference between EAL and
EFL products in the marketplace.

       Because the majority of a lubricant is composed of the base oil, the base oil used in an
EAL must be biodegradable. The three most common categories of biodegradable base oils are:
1)  vegetable oils, 2) synthetic esters, and 3) polyalkylene glycols. Due to the low toxicities of
these three types of base oils, aquatic toxicity exhibited by lubricants formulated from them is
typically a consequence of the performance enhancing additives or thickening agents (found in
greases) used in the formulation, which can vary widely.

Environmentally Acceptable Lubricants            Section 2- Types of Environmentally Acceptable Lubricants

                                                                       SECTION 2


       Environmentally acceptable lubricants are commonly classified according to the type of
base oil used in their formulation. In general, lubricants consist of approximately 75 to 90
percent base oil. Greases contain approximately 10 percent thickening agent, which is usually a
soap (Gow, 2009), in addition to the base oil. The remaining fraction of a lubricant formulation
consists of performance enhancing additives. A lubricant formulation can include hundreds of
additives, which address performance issues specific to their application and performance
shortcomings of the base oil. Additives are commonly used to address oxidative aging, corrosion,
high pressure, low or high temperature conditions, phase transition, shear, foaming, and
hydrolysis (particularly for vegetable and synthetic ester-based oils) (Habereder et al., 2008).

       The number of additives that are compatible with vegetable oils, synthetic esters, or
polyalkylene glycols is small relative to the number of additives that are compatible with
conventional (mineral) base oils. However, this is changing  as a result of increased emphasis on
EAL development. Additive manufacturers are working more closely with the lubricant industry
to design additives that are suitable for improving the performance of EALs that are more
environmentally benign (Aluyor et al. 2009). For some of the more stringent labeling programs
(see Section 5), additives used in EAL must be both ashless (i.e., containing no metals other than
Ca, Na, K, Mg) and non-toxic (Haberader et al. 2009). Among the soaps, calcium-based soaps
are considered less toxic compared to other types (e.g., lithum-based), and soaps in general are
considered less toxic than graphite thickeners (Gow, 2009).


       The main components of vegetable oils are triglycerides (natural esters), the precise
chemical nature of which is dependent on both the plant species and strain from which the oil is
obtained (Haberader et al., 2008 and Nelson,  2000). Outside the U.S., rapeseed is the most
commonly used crop for creating vegetable oil lubricants (Cuevas, 2005 and Habereder et al.,
2008). In the U.S., the  most commonly used crops for producing vegetable oil lubricants are
canola, soybeans, and sunflowers (Nelson,  2000).

       Largely because of performance issues related to low thermo-oxidative stability and poor
cold flow behavior, pure vegetable oil-based lubricants comprise a relatively small fraction of the
biolubricant market, although recent research developments have shown promise for overcoming
these shortcomings (Erhan et al., 2006 and Kabir et al., 2008). Another reason is that vegetable
oil-based lubricants are much less available than synthetic esters (Bremmer and Plonsker, 2008).
To date, their most common commercial applications include hydraulic fluid and wire rope


       Lubricants based on synthetic esters have been in production longer than any other class
of biolubricant and were first used for jet engine lubrication in the 1950s. Synthetic esters can be
prepared by the esterification of biobased materials (i.e., some combination of modified animal
fat and vegetable oil). Because synthetic esters can be specifically tailored for their intended

Environmentally Acceptable Lubricants             Section 2- Types of Environmentally Acceptable Lubricants
application, they have many performance advantages over pure vegetable oils, and are used as
the base oil in lubricants for many vessel applications, including hydraulic oil, stern tube oil,
thruster oil, gear lubricant, and grease (ACE, 1999 and Habereder et al., 2008). Synthetic esters-
based EALs are developed and marketed by several major oil companies including British
Petroleum, Chevron, Exxon/Mobil and Gulf, and are currently the most widely commercially
available class of EAL.


       Polyalkylene glycols (PAG) are synthetic lubricant base oils, typically made by the
polymerization of ethylene or propylene oxide (Brown, 1997). Depending on the precursor, they
can be soluble in either oil (propylene oxide) or water (ethylene oxide) (Greaves, 2008  and
Habereder et al., 2008). Although they are made from petroleum-based materials, PAGs can be
highly biodegradable,  particularly the water soluble PAGs (Greaves, 2008; Sada et al., 2008; and
Sada et al., 2009).

2.4    WATER

       At least one company has developed a completely seawater-lubricated stern tube system
that uses non-metallic bearings in place of metal bearings. This system is currently in place in
over 500 commercial vessels,  including several Carnival Corporation cruise ships (Carter, 2009).

Environmentally Acceptable Lubricants         Section 3- Considerations for EALs in the Aquatic Environment

                                                                       SECTION 3



       A number of factors must be considered when selecting lubricants for use in the aquatic
environment. Vessels require a variety of lubricants for different applications and on-ship storage
can be limited. Consequently, the most useful lubricants are those that can perform well in a
variety of applications (Rana, 2001). Additionally, lubricants must be widely available; in the
case of some larger ocean going vessels, compatible lubricants must be available at ports around
the globe (Blanken, 2006).

       Marine environments are characterized by high humidity conditions, and seawater ingress
can pose serious lubrication problems in sealed compartments, such as stern tubes and hydraulic
systems (Rana, 2001). Stern tube seals are highly susceptible to leakage, both from normal
operations, including vibrations and misalignment, and from contact with nets or fishing lines
(Sada et al., 2008 and Carter, 2009). The constant presence of seawater increases the potential
for corrosion, requiring thicker greases to repel water and corrosion inhibitors to minimize
corrosion following seawater ingress. In addition, lubricants subject to frequent contact with
water have a greater likelihood of undergoing some degree of biodegradation (ACE,  1999).


       Stiffer greases (i.e., National Lubricating Grease Institute grade 3 or higher) are typically
used in marine applications as they repel water more effectively. Lithium-based thickeners are
the most commonly used thickening agents, as they are considered to have the best all-purpose
formulation. Although they comprise a much smaller fraction of the grease market, calcium-
based thickeners do perform well under cool, wet conditions, and are used in formulations for
some marine applications (e.g., propeller housing and water pumps). Anhydrous calcium-based
greases are becoming increasingly common in Europe, where there is a greater emphasis on
adoption of EALs, because of their relatively low toxicity and better performance at higher
temperatures (Gow, 2009).


       In addition to their environmental benefits (i.e., high biodegradability and low aquatic
toxicity), vegetable oils possess several advantageous performance qualities compared to mineral
oils. They have a higher viscosity index (meaning they do not thin as readily at high
temperatures) and they have a higher lubricity, or ability to reduce friction (Nelson, 2000;
IENICA, 2004). Vegetable oil-based lubricants also have a high flash point, meaning they
combust at higher temperatures than conventional mineral oils. They perform well at extreme
pressures, and do not react with paints, seals, and varnishes (ACE, 1999).

       Vegetable oils possess several major performance drawbacks, however, which have
limited their use in the formulation of EALs. The primary limitations are (1) poor performance at
both low and high temperatures and (2) oxidative instability (Erhan et al., 2006 and Habereder et
al., 2008). Vegetable oils thicken more than mineral oils at low temperatures and are subject to

Environmentally Acceptable Lubricants          Section 3- Considerations for EALs in the Aquatic Environment
increased oxidation at high temperatures, resulting in the need for more frequent oil changes.
These shortcomings can be addressed with the use of selected additives for a formulation or
through the selective breeding and use of high-oleic oils (i.e., oils that contain more oleic acid, a
monounsaturated fat, and less polyunsaturated fats) that are less susceptible to oxidative
instability.  The use of selected additives can increase production costs and may decrease the
overall environmental acceptability of the product (Nelson, 2000; Bremmer and Plonsker, 2008).
In addition, vegetable oils remove mineral oil deposits, resulting in the need for more frequent
oil filter service.

       Vegetable oil lubricants  are more expensive than comparable mineral oil lubricants, as a
function of both higher base oil  costs, as well  as higher costs for the base oil-compatible
additives (ACE, 1999). Although Miller (2008) stated that vegetable oil lubricants cost
approximately double that of mineral base oils, more recent information obtained through
personal communication with a major lubricant supplier suggests that the current cost premium
for these biolubricants may be only 20% more. Changing  from a mineral to a vegetable oil
lubricant is relatively simple, as vegetable oils and mineral oils are compatible and vegetable oil
lubricants will perform properly if some mineral oil residue remains. Because the overall
formulations are less toxic, disposal costs are  generally lower; however, this may not always be
the case, as fewer disposal stations are able to accept spent biobased lubricants (ACE, 1999;
Nelson, 2000; and Bremmer and Plonsker, 2008).


       Synthetic esters perform well across a wide range  of temperatures, have a high viscosity
index, possess high lubricity, provide corrosion protection, and have high oxidative stability
(ACE, 1999 and Habereder et al., 2008). Because they contain biobased material, many synthetic
esters satisfy testing requirements for biodegradability and aquatic toxicity, although they tend to
be less readily biodegradable than pure vegetable oil-based lubricants (WISE Solutions, 2006).
Synthetic ester-based lubricants can be more or less toxic  than vegetable oil-based lubricants,
depending  on the aquatic toxicity of the additives used in  the formulation. The only notable
performance issue with synthetic esters is that they are incompatible with some paints, finishes,
and seal materials (ACE, 1999).

       Synthetic esters are generally the most expensive class of EAL (Miller, 2008). Synthetic
ester-based biolubricants cost approximately 2-3 times that for  comparable conventional mineral
oil-based lubricants. As the availability of synthetic ester-based EALs increases, this cost
differential is expected to decline.

       The relatively  higher cost of synthetic esters is  somewhat mitigated by their high
oxidative stability, which results in longer lubricant life. This is particularly applicable to areas
of the vessel that require more frequent lubricant changes (e.g., engine  oil, hydraulic fluid, stern
tube-thruster fluid). Synthetic esters are compatible with mineral oil, which reduces changeover
costs, but similar to vegetable oils in that their effectiveness at removing mineral oil deposits can
cause filters to clog during the period initially following lubricant changeover (ACE, 1999).
Disposal costs are  similar to those for vegetable oil-based lubricants.

Environmentally Acceptable Lubricants         Section 3- Considerations for EALs in the Aquatic Environment

       Lubricants consisting of polyalkylene glycols (PAGs) have the best overall low- and
high-temperature viscosity performance among all of the classes of biolubricants. For marine
applications, water soluble PAG EALs are attractive because, in addition to their high
biodegradability, they retain their performance characteristics following water influx better than
other EALs; as a result, PAG EALs have received consideration as a stern tube lubricant (Sada et
al., 2008; Sada et al., 2009). The water solubility of ethylene oxide-derived PAGs can improve
performance relative to other lubricants by maintaining viscosity following some fraction of
water influx (up to 20% in some laboratory tests), which can be of great importance for stern
tube lubrication (Sada et al., 2008; Carter, 2009). PAGs also perform well in terms of lubricity,
viscosity index, and corrosion protection. The relatively high viscosity and lubricity of PAGs has
resulted in the recent development of PAG-based thruster lubricants (Sada et al., 2009).

       Disadvantages associated with PAGs are that they are incompatible with mineral oils, as
well as most paints, varnishes, and seals (ACE, 1999; Sura et al., 2008). Because of this
incompatibility, they have the highest changeover costs  of any  class of EAL (Sada et al., 2008).
Additionally, water soluble PAGs may demonstrate increased toxicity to aquatic organisms by
directly entering the water column and sediments rather than remaining on the water column
surface as a sheen (Habereder et al., 2008).


       At the present, the global availability of EALs for different marine applications is
growing. One manufacturer of marine EALs, Castrol Bio Range, provided data demonstrating
that stern tube and thruster lubricant, hydraulic fluids, gear lubricants and grease were available
in the following global regions and countries (Pearce et  al., 2010; Castrol Marine, 2011):

       •     Americas: USA;
       •     Northern Europe: Belgium,  Denmark, Finland, France, Germany, Netherlands,
             Norway, Sweden, UK;
       •     Mediterranean: Italy, Spain, Turkey, UAE; and
       •     Asia-Pacific: China, Japan, Hong Kong, Singapore, Korea.

       Market cost data for EALs are unavailable, because manufacturers consider such data to
be proprietary marking information. The purchase prices of EALs are guarded closely by the
manufacturers, and EPA has generally been unable to obtain publicly available cost information
from EAL manufacturers. Operating costs for ship-owners and charterers using environmentally
preferable lubricants are expected to increase modestly relative to  conventional products,
although there can be efficiency gains from longer life (e.g., reduced corrosive properties,
enhance water contamination performance). However, the benefit  of using environmentally
preferable lubricants can be considerable in terms of reduced environmental impacts.

       Some indication of the cost of EALs relative to conventional lubricants was provided by
a major lubricant vendor and is tabulated in Table 1. Some specialized lubricants may have
higher costs.

Environmentally Acceptable Lubricants
Section 3- Considerations for EALs in the Aquatic Environment
                                  Table 1. Cost of EALs
Lubricant Base Oil
Mineral Oil
Vegetable Oils
Synthetic Esters
Polyalkylene Glycols
Ratio of EAL cost to
Conventional Mineral Oil
Lubricant Cost
2 to 3
2 to 3
       An informal survey of websites for the boating supply distributors West Marine,
Jamestown Distributors, Aerospace Lubricants, Inc. and Aqua Lube, demonstrates that semi-
synthetic ester and full synthetic ester engine oil, gear oil, and greases are the most commonly
available biolubricants for recreational vessel owners. The costs of full synthetic ester
formulations (primarily two cycle and four stroke engine oils) range from 1.4-1.8 times the costs
of comparable conventional (mineral oil) formulations. These distributor websites do not provide
information as to whether any of the synthetic ester-based biolubricants meet certification
standards that would classify them as EAL. For commercial vessels, relative pricing information
for Gulf Oil marine lubricants reveals that costs for biolubricants advertised (synthetic gear oil,
compressor oil, and coolant oil, the three synthetic lubricants), ranged from approximately 1.3-
2.5 times (coolant oil) to 3.5-4.3 times (gear oil and compressor oil) the cost for comparable
mineral oil  products (Gulf Marine, 2010). It may be reasonable to assume that the cost premium
for EALs is similar to these price ratios.

       Many countries, primarily in Europe, encourage the manufacture  and consumption of
EALs. Examples are through tax exemptions on environmentally acceptable base oils, taxes on
mineral oils, subsidies to consumers to cover the price difference between conventional and
EALs, or preferential purchasing programs that require a percentage of certain classes of product
to be made  from renewable resources (Habereder et al., 2008; IENICA, 2004; and WISE
Solutions, 2006).

Environmentally Acceptable Lubricants                   Section 4 - Defining "Environmentally Acceptable"

                                                                      SECTION 4


       Lubricants may be labeled using a variety of terms to signify that they are
environmentally friendly. Although EFLs are most likely to be tested for biodegradability,
aquatic toxicity and bioaccumulation potential, there are numerous other methods, which vary in
their sensitivity.


       Biodegradability is a measure of the breakdown of a chemical (or a chemical mixture) by
micro-organisms. Primary biodegradation is the loss of one or more active groups in a chemical
compound that renders the compound inactive with regard to a particular function (Betton,
2009). Primary biodegradation may result in the conversion of a toxic compound into a less toxic
or non-toxic compound. Ultimate biodegradation,  also referred to as mineralization, is the
process whereby a chemical compound is converted to carbon dioxide, water, and mineral salts
(Betton, 2009).

       In addition to primary and ultimate biodegradation, biodegradation is also defined by two
other operational properties: inherent biodegradability and ready biodegradability. A compound
is considered inherently biodegradable so long as it shows evidence of biodegradation in any test
for biodegradability. Readily biodegradable is an operational definition that some fraction of a
compound is ultimately biodegradable within a specific timeframe, as specified by a test method.

       Common test methods, such as those developed by the Organization for Economic
Cooperation and Development (OECD), the Coordinating European Council (CEC), and the
American Society for Testing and Materials (ASTM), for determining lubricant biodegradability
are OECD 301B (the Modified Strum test), ASTM D-5864, and CEC L-33-A-934. Both OECD
301B and ASTM D-5864 measure ready biodegradability, defined as the conversion of 60% of
the material to CO2 within a ten day window following the onset of biodegradation, which must
occur within 28 days of test initiation (Willing, 2001). In contrast, the CEC method tests the
overall biodegradability of hydrocarbon compounds and requires 80%  or greater biodegradability
as measured by the infrared absorbance of extractable lipophilic compounds (CEC, 1997 and
WISE Solutions, 2006). Unlike the OECD and ASTM methods, the CEC method does not
distinguish between primary and ultimate biodegradability, and is considered to be a less
stringent test (Blanken, 2006).

       Table 2 lists some of the internationally standardized test methods  that measure

Environmentally Acceptable Lubricants
Section 4 - Defining "Environmentally Acceptable"
    Table 2. Internationally Standardized Test Methods for Measuring Biodegradability
Test Type
Ready Biodegradability
(A substance is considered
to be inherently
biodegradable using any
of these tests if it shows
>20% biodegradability
within the test duration)
Hydrocarbon degradability
Screening tests (semi-official)
Test Name
Strum test
MITI test
Closed bottle test
Strum test
Shake flask test
BODIS test
CEC test
CO2 headspace test
OECD 301 A
EPA 560/6-82-003
ISO 10708
ISO 14593
Source: modified from Willing, 2001
a. DOC - dissolved organic carbon; CO2 - carbon dioxide; BOD - biochemical oxygen demand; COD - chemical oxygen
b. Ready biodegradability is defined as complete mineralization of a compound into water, carbon dioxide, and mineral salts
according to a specific test criterion. Pass levels indicate the percentage of complete mineralization (or ultimate biodegradation)
as indicated by the "Measured Parameter" that must occur for a product to be classified as readily biodegradable.

       Table 3 summarizes biodegradation rates for different lubricant base oils. Ester-based oils
have a much greater inherent biodegradation rate due to the presence of carboxylic acid groups
that bacteria can readily utilize (Mudge, 2010). These compounds are also more water soluble
than compounds that do not contain polar functional groups, the absence of which can reduce
their bioaccumulation potential.

      Table 3. Summary of Differential Biodegradation Rates by Lubricant Base Oils
Lubricant base oil
Mineral oil
Polyalkylene glycols (PAG)
Synthetic Ester
Vegetable Oils
Base oil source
Petroleum - synthesized hydrocarbon
Synthesized from biological sources
Naturally occurring vegetable oils
Persistent / Inherently
     Source: Mudge, 2010


       In addition to possessing a certain percentage of readily biodegradable material, an EAL
must also demonstrate low toxicity to aquatic organisms. Test methods to demonstrate toxicity
include the OECD tests series 201-4, and 209-212; and corresponding USEPA environmental
effect test guidelines from EPA 560/6-82-002. The most common aquatic toxicity tests for
assessing EALs are the 72-hour growth test for algae (OECD 201), the 48-hour acute toxicity test
for daphnia (OECD 202), and the 96-hour toxicity test for fish (OECD 203). Analogous USEPA
tests are  sections EG-8, EG-1, and EG-9 of EPA 560/6-82-002 for algae, daphnia, and fish,
respectively. A listing  of all of the OECD aquatic toxicity tests is included in Table 4.

Environmentally Acceptable Lubricants
Section 4 - Defining "Environmentally Acceptable"
                          Table 4. OECD Aquatic Toxicity Tests
Test Title, with Species
Growth Inhibition Test, Alga
Acute Immobilization Test, Daphnia sp.
Acute Toxicity Test, Fish
Prolonged Toxicity Test: 14-Day Study, Fish
Respiration Inhibition Test, Bacteria
Early-Life Stage Toxicity Test, Fish
Reproduction Test, Daphnia magna
Short-term Toxicity Test on Embryo and Sac-fry Stages, Fish
Test Number
OECD 201
OECD 202
OECD 203
OECD 204
OECD 209
OECD 210
OECD 211
OECD 212
       In general, the vegetable oil and synthetic ester base oils have a low toxicity towards
marine organisms with the LCso for fish toxicity reported as being -10,000 ppm for fatty acid
esters and glycerol esters (see Table 5) (van Broekhuizen, 2003). Water soluble PAGs may
demonstrate increased toxicity to aquatic organisms by directly entering the water column and
sediments rather than remaining on the water column surface as a sheen (Habereder et al. 2008).

                 Table 5. Summary of Comparative Toxicity of Base Oils
Lubricant base oil
Mineral oil
Polyalkylene glycols (PAG)
Synthetic Ester
Vegetable Oils
Base oil source
Petroleum - synthesized hydrocarbon
Synthesized from biological sources
Naturally occurring vegetable oils
          Source: Mudge, 2010
          a. Solubility may increase the toxicity of some PAGs

       As with many oily chemicals, the toxicity in some tests is not measureable as the LCso
exceeds the water solubility of the compound (Mudge, 2010). In such cases, it is possible to
induce physical effects such as smothering but this is not a chemical toxic effect.  Some
methodologies use the water-accommodated fraction, the part of the oil that disperse or dissolves
in water, although this is not a true reflection of the entire oil behavior in the marine

       The petroleum-based oils have a greater toxicity to biota in the marine food  chain
compared to the other base oil sources (Mudge, 2010). This is related to the more rapid
breakdown of petroleum-based oils once in the  sea, which ultimately affects the potential for
bioaccumulation. The toxicity of petroleum-based oils is also dependent upon additives used in
formulations and metabolites  produced in biodegradation.

       The use of additives is dependent on the choice of base oil and the intended  function of
the lubricant (Mudge, 2010). However, several  of the more toxic compounds in formulations are
also the ones with poor degradability. The overall product toxicity may be significantly reduced
by switching to a biologically-sourced base oil used in conjunction with low toxicity additives.

Environmentally Acceptable Lubricants                   Section 4 - Defining "Environmentally Acceptable"

       The propensity of a substance to bioaccumulate is another property of a lubricant that is
often considered in the qualification of a product as an EAL (Mudge, 2010). Bioaccumulation is
the build-up of chemicals within the tissues of an organism over time. The longer the organism is
exposed to a chemical and the longer the organism lives, the greater the accumulation of the
chemical in the tissues (Mudge, 2010). If the chemical has a slow degradation rate or low
depuration rate within an organism, concentrations of that chemical may build-up in the
organism's tissues and may eventually lead to adverse biological effects. It is, therefore,
desirable to use compounds in formulations that do not bioaccumulate. It may not be possible to
phase out all bioaccumulating compounds, but it is feasible to use chemicals that have a lower
bioaccumulation potential,  either through not being taken up as readily or by degrading more
quickly both in the environment and in the organism.

       The bioaccumulation potential of a compound is directly related to its water solubility;
chemicals that are not water soluble tend to move into fatty tissues rather than to staying in
water. These lipophilic chemicals include most of the compounds used in  the manufacture of the
base oil in lubricants. The water solubility of a compound is related to the type of atoms in the
molecule; compounds comprised solely of carbon and hydrogen tend to have the lowest
solubility in water. Compounds of this type includes alkanes, which form  almost 90% of the
current base oil in conventional lubricant formulations. The inclusion of one or more oxygen
atoms in  a molecule will, in general, increase the water solubility and reduce bioaccumulation.
Compounds with oxygen also tend to degrade more quickly in the environment or be excreted
faster from organisms.

       Many naturally-derived base oils used in lubricants are formulated around carboxylic
acids, which increase water solubility  and degradation; therefore, their bioaccumulation potential
is reduced in comparison to alkane-based oils.

       It has been assumed for some time that larger molecules are not bioaccumulated as they
are unable to physically pass through the membranes of cells and be incorporated into the living
cells (Arnot et al., 2010). Therefore, when designing lubricant formulations, the molecular size
of the components of the base oil are considered as they will directly affect the rate of uptake.
There has been several criteria proposed over the past few years to describe the point at which
chemicals are no longer taken up in the body and bioaccumulated (Arnot et al., 2010). In an
evaluation of data for esters, there was a strong link between the log Kow (the logarithm of the
partitioning coefficient of a substance in n-octanol and water) and the log  BCF (a measure of the
bioconcentration from water into aquatic organisms), while the other factors had less well-
defined relationships. The selection criteria chosen by the Canadian Government and United
Nations Environment Program (UNEP) (Canada, 2000 and UNEP, 2001)  and the U.S.
Environmental Protection Agency (USEPA, 1999) led to cut-off log Kow values of ~5.  There is
no single criterion to adequately describe the BCF; one study proposes a holistic approach
integrating several factors,  including measured uptake and elimination rates (Arnot et al., 2010).

       Certain labeling programs, most notably the European Eco-label (see Section 5), require
demonstration that a product is not bioaccumulative. This can be accomplished in a number of
ways for organic compounds, such as  measuring log Kow, or BCF. The two most common test

Environmentally Acceptable Lubricants
Section 4 - Defining "Environmentally Acceptable"
methods for establishing bioaccumulation potential are OECD 117 and 107. For these tests, the
test substance is added to a mixture of octanol and water and its dissolution in each phase is
detected using gas chromatography or an infra red detector. The bioaccumulation of the
substance is measured by establishing its partition coefficient (expressed as log Kow) in octanol
and water. Substances that have a tendency to bioaccumulate will preferentially dissolve in the
octanol  rather than the water, and octanol mimics the fatty tissue in an organism. Therefore, the
greater the log Kow, the  greater the likelihood that the substance will bioaccumulate.

       Partition coefficients for the marine environment are normally measured on a log scale
between 0-6. Substances with log Kow <3 are deemed not to bioaccumulate and those with log
Kow >3 are deemed to be bioaccumulating.

       Seawater may increase the likelihood of uptake by organisms in comparison to freshwater
due to "salting out" of lipophilic substances. Therefore, although freshwater is used in these test
methods, as long as conservative acceptance limits are set, they can be used as an indicator of
bioaccumulation potential in the marine environment. The use of these test methods as an
indicator of a substance's bioaccumulation potential can negate the need to carry out in vivo or in
vitro fish or mussel testing.

       In summary, the level to which a component of the product is bioaccumulated in an
organism is dependent on the environmental and biological half-lives of the compounds (some
will degrade before being incorporated into an organism and some will be metabolized within the
organism), as well as the lipophilic nature of the compounds (as measured by water solubility).
Any component that has low water solubility may potentially bioaccumulate in an organism. In
the case of lubricants, fatty acid-containing components have reduced bioaccumulation potential
due to greater water solubility and higher biodegradation rates. This is one distinct advantage in
using esters over the other carbon and hydrogen alone base oil types (see Table 6).

            Table 6. Summary of Bioaccumulation Potential by Base Oil Types
Lubricant base oil
Mineral oil
Polyalkylene glycols (PAG)
Synthetic Ester
Vegetable Oils
Base oil source
Petroleum - synthesized hydrocarbon
Synthesized from biological sources
Naturally occurring vegetable oils
Potential for
        Source: Mudge, 2010

       A summary of the major factors regarding biodegradation, toxicity and bioaccumulation
potential, for each of the base oil types is shown in Table 7. In this table, the three major criteria
are presented for each base oil and color-coded to indicate the environmental outcome. The
biodegradability of a lubricant reflects that of the lubricant's base oil, while the degree of aquatic
toxicity is typically a consequence of the performance enhancing additives (or thickening agents)
within the formulation. The base oils that degrade quickly are considered more preferable than
those that do not rapidly degrade, although there might be a trade-off with regard to the depletion
of oxygen during compound metabolism. The compounds that do not bioaccumulate and are

Environmentally Acceptable Lubricants
Section 4 - Defining "Environmentally Acceptable"
relatively less toxic are considered more preferable than those that bioaccumulate and have
higher toxicities.

      Table 7. Comparative Environmental Behavior of Lubricants by Base Oil Type
Lubricant base
Mineral oil
glycols (PAG)
Synthetic Ester
Vegetable Oils
Base oil source
Petroleum - synthesized
Synthesized from
biological sources
Naturally occurring
vegetable oils
Persistent /
Potential for
Source: Mudge, 2010
a. Solubility may increase the toxicity of some PAGs

       Currently, a majority of lubricant base oils (mineral oils) have the lowest biodegradation
rate, a high potential for bioaccumulation, and a measurable toxicity towards marine organisms.
In contrast, the base oils derived from oleochemicals (vegetable oils and synthetic esters)
degrade faster, have a smaller residual,  do not bioaccumulate appreciably and have a lower
toxicity to marine organisms. PAG-based lubricants are also generally biodegradable and do not
bioaccumulate; however, some PAGs may be more toxic due to their solubility in water. On the
basis of this simple comparison, lower environmental impacts will arise if a greater proportion of
base oils are manufactured from biologically-sourced materials.

Environmentally Acceptable Lubricants      Section 5 - Environmentally Acceptable Lubricant Labeling Program

                                                                        SECTION 5



       To minimize confusion in the marketplace and to increase public awareness and create
sensitivity for environmentally preferable products, national and international labeling programs
have been developed, primarily in Europe (Habereder et al., 2008). These labeling programs
have defined and established methods to measure the properties of a lubricant that would qualify
it as being environmentally acceptable. The labeling programs can aid the purchasing decisions
of a vessel operator by helping to remove uncertainty. The principal national and international
labeling certification programs for biolubricants and EALs are presented below.


5.1.1   Blue Angel

       The first national labeling scheme for lubricants was the German Blue Angel label,
developed in 1988. Criteria have been developed for several classes of lubricants, including
hydraulic fluids, lubricating oils, and greases. In order to qualify for certification, a lubricant
must possess the following characteristics: biodegradability; low toxicity to aquatic organisms;
non-bioaccumulative; and no dangerous components (such as carcinogens or toxic substances as
defined by Germany's Ordinance on Hazardous Substances). A product must also pass technical
performance characteristics appropriate for its use. Biodegradability can be demonstrated using
OECD tests 301B-301Fto measure ultimate biodegradability  or CEC L-33-A-934 to measure
primary biodegradability. Blue Angel's requirement for ultimate biodegradability is the primary
difference between the Blue Angel labeling certification program and other national and
international certification programs. Aquatic toxicity is determined according to OECD 201-203.

       Products receiving the Blue Angel certification must also pass a series of technical
performance requirements that depend on the class of lubricant. Unlike some of the other
labeling programs, the Blue Angel certification does not have any requirements for renewability;
consequently, lubricants comprised completely of petroleum-sourced components can receive
Blue Angel certification. Nevertheless, Blue Angel certification is considered rather stringent,
and the proportion of lubricants receiving this certification remains low, with the majority being
hydraulic fluids (Habereder et al., 2008). A complete list of all lubricants that carry the Blue
Angel certification can be found at http://www.blauer-engel.de/en/products_brands/

5.1.2   Swedish Standard

       Another national labeling scheme for lubricants is the  Swedish Standard, which includes
standards for hydraulic fluids (SS 155434) and greases (SS  155470). Evaluation of a lubricant
under the Swedish Standard involves testing for biodegradability and aquatic toxicity, as well as
sensitizing properties of a lubricant formulation and its components (Habereder et al., 2008). The
Swedish Standard evaluates biodegradability using ISO test methods (e.g., ISO 9439), and has
varying requirements, depending upon class, for renewable resources content (SP 2010). The


Environmentally Acceptable Lubricants      Section 5 - Environmentally Acceptable Lubricant Labeling Program
Swedish Standard is unique because it was conceived and developed as a collaborative project
between government and industry. This program has more listed lubricant products, particularly
hydraulic fluids, than any other national labeling program (IENICA, 2004).


5.2.1   Nordic Swan

       The first international labeling program for EALs was the Nordic Swan program,
encompassing Norway, Sweden, Finland, Iceland, and Denmark.  This program was initially
introduced for hydraulic oil, two-stroke oil, grease, and transmission and gear oil (IENICA,
2004). The Nordic Swan certification addresses biodegradability, aquatic toxicity (OECD 201
and 202), technical performance, and renewability. The renewability requirements are the highest
of all the labeling programs (e.g., at least 65% renewable content for hydraulic fluid,
transmission fluid, gear oil, or grease, and at least  50% for two-stroke  oil).  Consequently, very
few lubricants bear the Nordic Swan label (Habereder et al., 2008).

5.2.2   European Eco-label

       The European Union has adopted a single European Eco-label. The Eco-label is
considered to be the first major advancement towards creating a single international standard,
and is becoming the most generally accepted label. The Eco-label for lubricants was established
in 2005, and includes hydraulic fluids, greases, and total loss lubricants, such as two-stroke oils.
This labeling scheme consists of seven criteria encompassing biodegradability, aquatic toxicity,
bioaccumulation, and the presence of certain classes of toxic substances (Habereder et al., 2008).
A complete list of all lubricants that carry the European Eco-Label can be found at

       The ecological criteria for Eco-label lubricants aim at promoting products that have a
reduced impact on the water and soil during their use and contain a large fraction of biologically-
based material.  Since this is the most widely accepted labeling program, the requirements for this
labeling scheme are described in detail below.       Dangerous Materials

       Before a lubricant can be considered for the Eco-label, it is determined that neither the
formulation nor any of the main components are on the list of R-phrases (risk  phrases) pertaining
to environmental and human health hazards according to the European Union  Dangerous
Preparations Directive (IENICA, 2004). These include qualities such as explosiveness,
flammability, carcinogenic potential, volatility, potential to cause birth defects, etc.       Toxicity

       Aquatic toxicity can be evaluated either for the complete formulation and main
compounds (those compounds comprising at least 5% of the formulation) or for each constituent
substance. Greases must be evaluated for each constituent substance unless it can be shown that
the thickening agent is at least inherently biodegradable (see below). All formulations and
components must pass both OECD 201 and 202 for acute toxicity testing, and OECD 210 or 211
for chronic toxicity testing. If evaluated for the formulation and main constituents, the LCso (i.e.,


Environmentally Acceptable Lubricants      Section 5 - Environmentally Acceptable Lubricant Labeling Program
concentration of a compound or mixture that will kill half of the sample population of a specific
test-organism in a specified period) of hydraulic fluids must be at least 100 mg/L and the LCso of
greases, two-stroke oils, and all other total loss lubricants must be at least 1000 mg/L (European
Commission, 2009). If the evaluation is based on each constituent substance, then constituents
that comprise less than 20% of hydraulic fluids can have an LCso of 10-100 mg/L or have a no
observed effect concentration (NOEC) of 1-10 mg/L; constituents that comprise less than 5% of
hydraulic fluids can have an LCso of 1-10 mg/L or have a NOEC of 0.1-1 mg/L; and constituents
that comprise less than 1% of hydraulic fluids can have an LC50 of less than 1 mg/L or have a
NOEC of 0-0.1 mg/L. For greases, two-stroke oils, and other total loss lubricants, the respective
percentages are 25%, 1%, and 0.1% (European Commission, 2009).        Biodegradability and Bioaccumulation

       Ninety percent or more of the total hydraulic oil formulation (75% for greases or two-
stroke oils) must be ultimately biodegradable, as determined according to any of OECD tests 301
A-F, or equivalent. Less than 5% of the hydraulic oil formulation (20% for greases or two-stroke
oils) must be inherently biodegradable. Inherent biodegradability can be defined as at least 20%,
but less than 60% or 70% biodegradable (depending on the test), for any of OECD 301 A-F, or it
can be defined as greater than 70% biodegradation in the OECD 302C test (or equivalent), or
greater than 60% biodegradation in the ISO 14593 test (European Commission, 2009).

       In addition to being biodegradable, a lubricant must not have the potential to be
bioaccumulative. A lubricant is considered not potentially bioaccumulative if one of the
following conditions  is met: it has a molar mass greater than 800 g/mol or a molecular diameter
greater than 1.5 nm; it has a log Kow less than 3 or greater than 7; or it has a measured BCF less
than 100 L/Kg (European Commission, 2004). Log Kow , which can be assessed using OECD
107, 117, or 123, or calculated, can be used to demonstrate bioaccumulation potential for organic
compounds only. For all other compounds, BCF must be measured using the flow-through fish
test given by OECD 305 (European Commission, 2004).        Restricted Substances

       Lubricant formulations must not include certain specific substances, including
halogenated organic compounds, nitrite compounds, metals or metallic compounds (with the
possible exception of sodium-, potassium-, magnesium-, lithium-, aluminum-,and calcium-based
soaps) (European Commission, 2004).        Renewable Content

       At least 50% of hydraulic oils and two-stroke oils, and at least 45% of greases, must
consist of renewable materials, with renewable defined as vegetable oils or animal fats
(European Commission, 2004). Given that 70-90% of a lubricant or lubricant grease is the
formulation's base oil, this requirement effectively excludes mineral oil lubricants from Eco-
label certification.        Other

       The final criteria for the Eco-label are for technical performance, which are specific to
the lubricant class in  question.


Environmentally Acceptable Lubricants      Section 5 - Environmentally Acceptable Lubricant Labeling Program
5.2.3   OSPAR

       The offshore oil and gas industry is highly regulated, particularly in the North Sea,
compared to other marine industries (Pearce et al, 2010). Considerable attention is given to the
chemicals used on and discharged from offshore oil facilities. Some of these chemicals, such as
well chemicals, are deliberately discharged during normal use, similar to the discharge of total
loss lubricants by the marine industry.

       The Convention for the Protection of the Marine Environment of the North-East Atlantic
(OSPAR Convention)2 is the current legal instrument guiding international cooperation on the
protection of the marine environment of the North-East Atlantic. Work under the Convention is
managed by the OSPAR Commission, which is made up by representatives of 15 contracting
Governments and the European Commission (represents the European Union).

       The standards for environmental compliance, which are defined within the OSPAR
Harmonized Mandatory Control Scheme (HMCS) regulations, require component level testing of
chemicals released to the marine environment for biodegradation, bioaccumulation, and toxicity.
These standards, which apply to the North Sea,  are being adopted by most other oil and gas
regulators around the world (including Australia, Canada, India, Indonesia and New Zealand) as
they are considered to be the most appropriate for measuring the overall impact of a substance -
not just its persistence (Pearce et al., 2010). Although these regulations  do not cover the shipping
industry, they may be considered the most appropriate standards for measuring the impact of
released chemicals in the marine environment.

       The OSPAR standards measure environmental performance of chemicals in terms of
persistence (biodegradation in seawater over a 28-day period, by OECD 306), bioaccumulation
(evaluation by measuring Kow using OECD 117 or 107) and marine toxicity to four North Sea
species (algae, copepods, sediment reworkers and bottom-dwelling fish). Testing is carried out
on each component, and must be conducted by an approved third-party  laboratory. The OSPAR
protocols for methods for the testing of chemicals used in the offshore oil industry are available
online (OSPAR, 2006). The mechanisms set out in the HMCS to ensure  and actively promote the
continued shift towards the use of less hazardous substances (or preferably non-hazardous
substances) are described in the OSPAR Decision 2000/2 on a Harmonised Mandatory Control
System for the Use and Reduction of the Discharge of Offshore Chemicals (OSPAR, 2000).


       A summary of the major EAL labeling programs discussed in this section (including
biodegradation, toxicity, bioaccumulation potential and other criteria) is provided in Table 8.
• www.ospar.org

Environmentally Acceptable Lubricants
Section 5 - Environmentally Acceptable Lubricant Labeling Program
                      Table 8. Comparison of EAL Labeling Programs
Blue Angel
Nordic Swan
OECD 301B-F (ultimate
934 (primary biodeg.)
ISO 9439
OECD 301 A-F (ultimate
biodeg.), OECD 302C or
ISO 14593
OECD 306 (degradation
under marine conditions)
OECD 201-203
OECD 201-202
OECD 201 and
202 (acute) &
OECD 210 or
211 (chronic)
Marine toxicity
to 4 species
OECD 305
A-E or Kow
OECD 107, 117 or 123
(Kow for organic
compounds) or OECD
OECD 117or 107 (Kow)
Other Criteria
Dangerous materials;
Renewable content;
Sensitizing properties
Renewable content;
Dangerous materials;
Restricted substances;
Renewable content;

NA - Not available

Environmentally Acceptable Lubricants                                         Section 6 - Conclusion

                                                                         SECTION 6


       Because much of the lubricant lost from a vessel directly enters the aquatic environment,
there is a greater focus on encouraging the implementation of EALs on vessels (see 2008 VGP,
page 24) (Carter, 2009). For all applications where lubricants are likely to enter the water, EAL
formulations using vegetable oils, biodegradable synthetic esters or biodegradable polyalkylene
glycols as oil bases instead of mineral oils can offer significantly reduced environmental impacts
across all applications. Although their use is increasing, EALs continue to comprise only a small
percentage of the total lubricant market.

       Among types of EALs used in vessels, hydraulic fluids are the most prevalent. Along
with chain saw oil, more hydraulic fluids carry the Blue Angel and European Eco-label than any
other class of lubricant. A major reason for the success of environmentally acceptable hydraulic
fluid is that some of the performance issues associated with EALs in open systems (particularly
those formulated with vegetable oil derived base oils), such as oxidation, temperature sensitivity,
and biodegradation following exposure to water, are less problematic in this closed system
(ACE, 1999).

       Stern tube leakage is a significant source of lubricant oil inputs to the aquatic
environment; therefore, the benefit of replacing mineral-oil-based stern tube lubricants with
EALs is expected to be considerable. Because of the inevitability of leaks, stern tube lubricants
are also subject to water influx and increased biodegradability associated with water contact.
While  still a niche market, environmentally acceptable stern tube lubricants formulated from
PAGs have shown to perform as well as a conventional stern tube lubricant, with the additional
benefit of maintained viscosity following water influx (Sada et al., 2009).

Environmentally Acceptable Lubricants                                              List of Figures

                                                                      SECTION 7


Aluyor, E.A., O. O. Obahiagbon and M. Ori-jesu. 2009. Biodegradation of vegetable oils: A
       review. Scientific Research and Essay. 4(6): 543-548.

Army Corps of Engineers. 1999. Chapter 8: Environmentally Acceptable Lubricants. In:
       Lubricants and Hydraulic Fluids. Engineering Manual 1110-2-1424. Department of the
       Army. Washington, DC.

Arnot et al., 2010. Molecular Size Cutoff Criteria for Screening Bioaccumulation Potential: Fact
       or Fiction? Integrated Environmental Assessment and Management — Volume 6,
       Number 2—pp. 210-224.

Betton, C.I. 2009. Chapter 15, Lubricants and Their Environmental Impact. In: Chemistry and
       Technology of Lubricants, 3rd Edition. Mortimer, R., M. Fox, and S. Orszulik, eds.
       Springer, Dordrecht, Heidelberg, London, New York. 547 pp.

Blanken, F. 2006. Friction in the Market: A Review of the market for Environmentally
       Acceptable Lubricants. ' Integral! eprojecf Bachelor IEM Process and Product
       Technology. University of Groningen.

Bremmer, BJ. and L. Plonsker. 2008. Bio-Based Lubricants: A Market Opportunity Study
       Update. Omni Tech International, LTD. Prepared for the United Soybean Board.

Brown, W. 1997. Chapter 5, Polyalkylene Glycols,Tribology Data Handbook, E. Richard
       Booser, CRC Press 1997, ISBN: 978-0-8493-3904-2

Canada. 2000. Persistence and Bioaccumulation Regulations SOR/2000-107. Minister of
       Justice, Canada.

Carter, C.D. 2009. "Elimination of a Ship Source Pollutant - STOP (Stern Tube Oil Pollution)."
       WMTC. Thordon Bearings, Inc.
       9_Thordon_Bearings_ver_2.pdf?1283356147. Accessed October 2010.

Castrol Marine. 2011. Castrol Bio Range.
       view/?book=007&page=l. Accessed March 2011.

Coordinating European Council (CEC), 1997. "Biodegradability of Two-Stroke Cycle Outboard
       Engine Oils in Water." http://www.cectests.org. Accessed December 2010.

Cuevas, Phoebe. 2010. Comparative Life Cycle Assessment of Biolubricants and Mineral Based
       Lubricants. Master's Thesis. University of Pittsburgh. Pittsburgh, PA.  101 pp.

Erhan, S.Z., B.K. Sharma and J.M Perez. 2006. Oxidation and  low temperature stability of
       vegetable oil-based lubricants. Industrial Crops and Products 24: 292-299.

Environmentally Acceptable Lubricants                                               List of Figures
Etkin, D.S. 2010. Worldwide analysis of in-port vessel operational lubricant discharges and
       leaks. Proc. 33rd Arctic and Marine Oilspill Program Technical Seminar: p. 529-554.

European Commission. 2009. Commission Decision of Establishing the Ecological Criteria for
       the Award of the Community Eco-Label to Lubricants. The Commission of the European

Gow, G. 2009. Chapter 14, Lubricating Grease. In: Chemistry and Technology of Lubricants, 3rd
       Edition. Mortimer, R., M. Fox, and S. Orszulik, eds. Springer, Dordrecht, Heidelberg,
       London, New York. 547 pp.

Greaves, M.  "Extending the applications for polyalkylene glycols using new technology
       concepts." Independent Union of the European Lubricants Industry (UEIL). The UEIL
       Annual Congress. 2008. http://www.ueil.org/news/documents/14.Greaves.pdf. Accessed
       Oct. 2010.

Gulf Marine. September, 1 2010. International Price List No. 2. http://www.gulf-
       marine .info/html/products/products. html
Habereder, T., D. Moore, and M. Lang. 2008. Chapter 26, Eco Requirements for Lubricant
       Additives. In: Lubricant Additive Chemistry and ,
       Rudnick, ed. CRC Press. Boca Raton, FL. 790 pp
Additives. In: Lubricant Additive Chemistry and Applications, 2nd Edition. Leslie R.
Interactive European Network for Industrial Crops and their Applications (IENICA). 2004.
       "Biolubricants: Market Data Sheet."
       http://www.ienica.net/marketdatasheets/biolubricantsmds.pdf. Accessed Oct. 2010.

Kabir, M.A., C.F. Higgs, III, and M.R. Lovell. 2008. A pin-on-disk experimental study on a
       green particulate-fluid lubricant. ASME Journal of Tribology. 130(4): 6 pp.
Miller, M. 2008. Chapter 18, Additives for Bioderived and Biodegradable Lubricants. In:
       Lubricant Additive Chemistry <
       Press. Boca Raton, FL. 790 pp.
Lubricant Additive Chemistry and Applications, 2nd Edition. Leslie R. Rudnick, ed. CRC
Mudge, S.M. 2010. Comparative environmental fate of marine lubricants. Unpublished
       manuscript. Exponent UK.

Nelson, J. 2000. "Harvesting lubricants." The Carbohydrate Economy. Org.
       s.htm. Accessed Oct 2010.

OSPAR. 2000. Convention for the Protection of the Marine Environment of the North-East
       Atlantic .  OSPAR Decision 2000/2 on a Harmonised Mandatory Control System for the
       Use and Reduction of the Discharge of Offshore Chemicals (as amended by OSPAR
       Decision 2005/1). OSPAR Convention for the Protection of the Marine Environment in
       the North-East Atlantic. Meeting of the OSPAR Commission, Copenhagen. June 26-30,

Environmentally Acceptable Lubricants                                              List of Figures
OSPAR. 2006. Convention for the Protection of the Marine Environment of the North-East
       Atlantic . OSPAR Protocols on Methods for the Testing of Chemicals Used in the
       Offshore Oil Industry. OSPAR Commission
       http://www.ospar.org/documents/dbase/publicati ons/p00237_protocols%20fish%20toxici
Pavlakis et al. 2001. On the Monitoring of Illicit Vessel Discharges Using Spaceborne SAR
       Remote Sensing. A Reconnaissance Study in the Mediterranean Sea. European

Pearce, J. 28 and 29 April, 2010. Reducing marine oil pollution by raising standards in marine
       lubricants. Motorship.32nd Propulsion & Emissions Conference. Hamburg.

Rana, Lt. Cdr. A. 2001. Selection of marine lubricants. IE(I) Journal-MR. 84:68-72.

Sada, H., S. Yamajo, D.W. Hawkins. 2008. An Environmentally Compatible Lubricant for
       Sterntubes and Marine Hydraulic Systems. Presented at the Advanced Naval Propulsion
       Symposium 2008 of the American Society of Engineers in Arlington, VA on Dec. 15-16,

Sada, H., D. Hawkins, P. Erikson, and Y. Wisenbaker. 2009. An environmentally preferable
       lubricant for tunnel and azimuth thrusters. Dynamic-Positioning Conference. Oct. 13-14
       Committee of the Marine Technology Society.  8 pp.

SP Technical Research Institute of Sweden, 2010.
       http ://www. sp.se/en/index/services/Lubricanting%20grease/Sidor/default. aspx

United Nations Environment Programme (UNEP). 2001. Final Act of the Conference of
       Plenipotentiaeres on the Stollkholm Convention on Persistent Organic Pollutants.

U.S. Environmental Protection Agency (USEPA), 1999. Category for Persistent,
       Bioaccumulative, and Toxic New Chemical Substances. Fed Reg 64: 60194-60204.

Van Broekhuizen, Pieter. 2003. Lubrication in Inland and Coastal Water Activities (LLINCWA).
       Taylor & Francis.

Willing, A. 2001. Lubricants based on renewable resources - an environmentally compatible
       alternative to mineral oil products. Chemosphere 43: 89-98.

WISE Solutions. 2006. "Biodegradability Primer." WISE Solutions, Inc.
       http://www.wisesolutions.net/WISEbiodegradabilityprimer.pdf Accessed Oct. 2010.