United States
                Environmental Protection
                Agency	
                     Prevention, Pesticides
                     And Toxic Substances
                     (7508W)	
EPA-738-F-93-016
September 1993
                R.E.D.   FACTS
                Tris(hydroxymethyl)-
                nitromethane
     Pesticide
Reregistration
   Use Profile
    All pesticides sold or distributed in the United States must be
registered by EPA, based on scientific studies showing that they can be used
without posing unreasonable risks to people or the environment. Because of
advances in scientific knowledge, the law requires that pesticides which
were first registered years ago be reregistered to ensure that they meet
today's more stringent standards.
    In evaluating pesticides for reregistration, EPA obtains and reviews a
complete set of studies from pesticide producers, describing the human
health and environmental effects of each pesticide.  The Agency imposes
any regulatory controls that are  needed to effectively manage each
pesticide's risks. EPA then reregisters pesticides that can be used without
posing unreasonable risks to human health or the environment.
    When a pesticide is eligible for reregistration, EPA announces this and
explains why in a Reregistration Eligibility Decision (RED) document.  This
fact sheet summarizes the information in the RED document for the
reregistration case Tris(hydroxymethyl) nitromethane, which contains the
active ingredient 2-(hydroxymethyl)-2-nitro-l,3-propanediol.

    2-(hydroxymethyl)-2-nitro-l,3-propanediol is used as a microbicide
and bacteriostat in disinfectants  and industrial preservatives.  Specifically, it
is used as an industrial preservative in metalworking fluids, secondary oil
field recovery waters, paper mills and commercial/industrial water cooling
systems;  as an in-can preservative in latex paints, polishes and detergents;
and as a disinfectant to control disease organisms in livestock and poultry
areas on farm premises and equipment.  It is formulated as a soluble liquid
concentrate, powder or pellets, and is applied through use of a metering
pump in industrial water systems, by  pouring into paints and polishes, and
as a spray to farm areas and equipment.

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    Regulatory
         History
Human  Health
  Assessment
      2-(hydroxymethyl)-2-nitro-l,3-propanediol was first registered in the
U.S. in 1955, as an industrial bactericide and slimicide.  EPA has issued
three relevant Data Call-In (DCI) Notices: the Antimicrobial DCI in March
1987, the comprehensive reregistration Phase 4 DCI in September 1992,
and a third DCI in August 1993, the latter for residue data.  Currently, nine
pesticide products are registered which contain this active ingredient.

Toxicity
      Studies using laboratory animals indicate that 2-(hydroxymethyl)-2-
nitro-l,3-propanediol is of low to moderate acute toxicity to mammals.  It
has been placed in Toxicity Category III  for acute oral, dermal and
inhalation effects  (Toxicity Category I indicates the greatest degree of acute
toxicity and Category IV the lowest).  It  has been placed in Category IV for
eye and skin irritation effects.  Since these studies were not conducted with
the technical grade (100%) powder, additional confirmatory acute inhalation
and eye irritation studies are required using that formulation.
      In a subchronic dermal toxicity study using rats,  there were no
treatment-related effects observed at any dose level.  In developmental
toxicity studies using rats and rabbits, treatment-related maternal effects
were observed in the high-dose groups.  No mutagenic effects were  seen in
a battery of studies.
      2-(hydroxymethyl)-2-nitro-l,3-propanediol decomposes to
formaldehyde under alkaline, warm conditions. Formaldehyde has been
classified by EPA as a Group Bl "probable" human carcinogen.  The
toxicity of formaldehyde has been a primary consideration in evaluating the
risks of 2-(hydroxymethyl)-2-nitro-l,3-propanediol.
Dietary Exposure
      No dietary exposure is expected as a result of the registered uses of 2-
(hydroxymethyl)-2-nitro-l,3-propanediol.  Its one potential food use, as  a
disinfectant in or on livestock premises and equipment, has been modified to
delete milk house and milking equipment uses, and to add restrictions to
poultry house uses which eliminate the means of exposure of edible
livestock tissue or eggs. Therefore, no tolerances (maximum residue limits)
or exemptions from tolerances are required.
Occupational and Residential Exposure
      2-(hydroxymethyl)-2-nitro-l,3-propanediol has many uses that may
involve exposure to workers, and exposure monitoring  data were required to
estimate combined inhalation and dermal exposure of mixers, loaders and
applicators in various use sites.

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     Worker exposure is considered significant for preservative and pulp
and paper mill uses, which involve open pouring methods.  However,
associated risks will be mitigated ten-fold by requiring use of a respirator
and personal protective equipment (PPE) including a long-sleeved shirt and
long pants, and shoes plus socks.
     Worker exposure is considered low for the poultry/livestock
disinfectant use, but is of concern since formaldehyde is an active ingredient
in the product, and since a spray method of application is involved.  Use of
PPE and a respirator are required, and will reduce any exposure  ten-fold.
     Worker exposure during cooling tower and metal working fluid uses is
considered very low. Again, PPE is required to reduce possible exposure to
formaldehyde.
     While post-application worker exposure to formaldehyde is minimal
for most uses of 2-(hydroxymethyl)-2-nitro-l,3-propanediol, the disinfectant
spray used in livestock/poultry premises, which contains the active
ingredient formaldehyde, causes post-application exposure of concern.
However, EPA's exposure estimate represents the worst case scenario, and
OSHA requires monitoring for formaldehyde before workers may reenter
treated premises. Therefore, post-application worker exposure is likely the
same or less than exposure during mixing, loading or applying the pesticide.
     Similarly, post-application worker exposure to formaldehyde from use
of the parent chemical in pulp and paper mills is of some concern.  Since
the Agency's exposure estimate is very conservative,  a post-application
inhalation exposure monitoring study is required only as confirmatory data.
Human Risk Assessment
     Since 2-(hydroxymethyl)-2-nitro-l,3-propanediol has no food uses, no
dietary risk exists. Overall, minimal risk and exposure are associated with
the use of this active ingredient.  The risks associated are due to its
degradation product, formaldehyde.
     EPA has examined the cancer risks of formaldehyde extensively.
Using the most widely accepted risk assessment methodology, the Agency
has estimated the refined upper bound cancer risk to mixers, loaders and
applicators from exposure to formaldehyde through use of 2-
(hydroxymethyl)-2-nitro-l,3-propanediol.  With PPE and respirators, these
risks range from 1.1 in 100,000 for preservative uses to 2.5 in 1,000,000
for poultry/livestock disinfectant uses.
     Post-application worker exposure to formaldehyde following the
livestock/poultry premise spray use  is of concern;  the upper  bound risk to
workers is estimated to be 2.5 in 1,000,000.  However, the Agency's
exposure estimate represents the worst case scenario.  Actual risks to
workers should be lower considering OSHA's formaldehyde monitoring
requirements.  Post-application exposure of pulp and paper mill workers is
conservatively estimated to be 2.7 in 100,000.  A post-application inhalation

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                  exposure monitoring study is required for this use, as confirmatory information.
                        In evaluating environmental effects, EPA focused on 2-
AsSGSSITIGnt   (hydroxymethyl)-2-nitro-l,3-propanediol rather than its degradation
                  product,  formaldehyde.  In the aquatic environment, the  active ingredient is
                  relatively stable. As it breaks down to formaldehyde, the latter chemical is
                  rapidly dissipated.  Therefore, the parent compound is of greater interest.
                  Environmental Fate
                        Based on the results of an exposure assessment model, the Agency
                  expects that 2-(hydroxymethyl)-2-nitro-l,3-propanediol used according to
                  the label will result in minimal exposure to the environment.  Concern
                  would arise only from its discharge into receiving waters from the industrial
                  uses or in the case  of spills,  accidents or misuse.  A hydrolysis study is
                  required  to confirm the chemical's degradation in the environment.
                  Ecological Effects
                        2-(hydroxymethyl)-2-nitro-l,3-propanediol  has a low order of acute
                  oral and  dermal toxicity to terrestrial mammals.  It may be slightly toxic to
                  upland game birds, but is practically non-toxic to waterfowl.   It also is
                  practically non-toxic to freshwater fish species on an acute basis.  It is
                  slightly toxic to freshwater aquatic invertebrates and mollusks, and
                  practically non-toxic to crustaceans.
                  Ecological Effects Risk Assessment
                        EPA conducted a Tier  Ic Estimated Environmental Concentration
                  (EEC) model to assess the residue levels of 2-(hydroxymethyl)-2-nitro-l,3-
                  propanediol in the receiving stream from several  use sites.  This model
                  provides  a reasonable worst  case estimate of the maximum concentration
                  that may occur immediately  downstream from  an industrial point source
                  discharge site.  The typical EEC values for all  uses of this active ingredient
                  are below the levels of concern for fish and invertebrates. Therefore, the
                  pesticide can be used at typical use sites without producing effluent above
                  levels of  concern.  Under a high exposure scenario, a high degree of risk
                  would be posed to aquatic organisms. However,  discharge of the pesticide
                  is regulated by the  National  Pollutant Discharge Elimination System
                  (NPDES) permit program administered by EPA.  Through this program,
                  the Agency is able to control the discharge of this pesticide and other
                  chemicals so that toxic levels are avoided.
                  Endangered Species
                        The high exposure scenarios described above exceed the levels of
                  concern for endangered aquatic organisms.  In addition,  the typical EEC
                  value for pulp  and paper mills exceeds the  level of concern for endangered
                  aquatic invertebrates. Effluent containing this  active ingredient should not
                  be discharged into streams or waterways where endangered aquatic
                  organisms are  known to reside.  EPA is working with the U.S. Fish and
                  Wildlife Service to develop a program to avoid jeopardizing the continued

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                          existence of identified species by the use of pesticides.  When this program
                          goes into effect, endangered species labeling will be required.

    Additional  Data        The generic data base for 2-(hydroxymethyl)-2-nitro-l,3-propanediol
            RedUJr0d   *s substantially complete.  However, for confirmatory purposes, EPA is
                          requiring acute inhalation and eye irritation studies using the technical grade
                          powder formulation, a post-application inhalation exposure worker
                          monitoring study,  and a hydrolysis study.  EPA also is requiring product-
                          specific data, including chemistry,  acute toxicology and efficacy studies, as
                          well as revised labeling for reregistration.

  Product LabGling        All end-use  products containing 2-(hydroxymethyl)-2-nitro-l,3-
ChanCIGS RGCIUirGd   propanediol must  comply with EPA's current pesticide product labeling
                          requirements. In addition:
                          •    Effluent Discharge Statement - All end-use products for indoor non-
                          food uses (industrial uses which discharge effluent), aquatic non-food
                          industrial uses, or terrestrial non-food uses must bear the following effluent
                          discharge statement:
                               "Do not discharge effluent containing this product into lakes, streams,
                               ponds, estuaries, oceans or public waters unless in accordance with the
                               requirements of a National Pollutant Discharge Elimination System
                               (NPDES) permit and the permitting authority has been notified in
                               writing prior to discharge. Do not discharge effluent containing this
                               product to sewer systems without previously notifying the local
                               sewage treatment plant authority.  For guidance contact your State
                               Water Board or Regional Office of EPA."
                          •    Use Site PPE Requirements and Entry Restrictions
                               •  In poultry/livestock premises, preservative and pulp and paper
                               mills, the PPE requirement for mixer/loader/applicators  is:
                               "Pesticide handlers must wear:
                                —Long-sleeved shirt and long pants
                                —Chemical-resistant gloves
                                —Shoes plus socks
                               In  addition,  when engaged in pouring this product,
                                —A respirator with either  an organic-vapor-removing cartridge with a
                               prefilter approved for pesticides (MSHA/NIOSH approval number
                               prefix TC-23C), or a canister approved for pesticides (MSHA/NIOSH
                               approval number prefix TC-14G)."
                               •  For metal working fluids  and cooling tower water uses, the PPE
                               requirement for mixer/loader/applicators is:
                               "Pesticide handlers must wear:
                                —Long-sleeved shirt and long pants
                                —Chemical-resistant gloves

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 Regulatory
Conclusion
      —Shoes plus socks"
      •  In poultry/livestock premises, post-application workers must
      observe the following use restriction on the labeling in the directions
      describing use as a disinfectant spray:
      "Entry by any person—other than a correctly equipped handler—is
      PROHIBITED in the entire enclosed building/structure from the start
      of application until aeration reduces the air concentration level of
      formaldehyde in the working area to less than 0.75  ppm. The air
      level concentration of formaldehyde must be measured before entry is
      permitted. (OSHA issued a final rule for the PEL  for formaldehyde
      as 0.75 ppm, May 27,  1992, Federal Register, Vol. 57, p. 22290.)
      Any handler who enters the  treated area during this entry-restricted
      period must wear:
      —Long-sleeved shirt and long pants
      —Shoes plus socks
      —A respirator with either an organic-vapor-removing cartridge with  a
      prefilter approved for pesticides (MSHA/NIOSH approval number
      prefix TC-23C), or a canister approved for pesticides (MSHA/NIOSH
      approval number prefix TC-14G)."

      The currently registered uses of 2-(hydroxymethyl)-2-nitro-l,3-
propanediol may pose low level cancer risks to workers from the degradate
formaldehyde, and could pose risks to aquatic organisms  under certain
conditions as industrial effluent containing the parent chemical is released
into receiving waters.  However, the uses will not cause unreasonable
adverse effects to humans or the environment, and are  eligible for
reregistration.
      Products containing 2-(hydroxymethyl)-2-nitro-l,3-propanediol as the
sole active ingredient will be reregistered once the required product-specific
data and revised labeling are received and accepted  by EPA.  Products also
containing other active ingredients will be reregistered  only after the other
active ingredients also are determined to be eligible for reregistration.
   For More
Information
     EPA is requesting public comments on the Reregistration Eligibility
Decision (RED) document for Tris(hydroxymethyl)nitromethane during a
60-day time period, as announced in a Notice of Availability published in
the Federal Register. To obtain a copy of the RED document or to submit
written comments, please contact the Pesticide Docket, Public Response and
Program Resources Branch, Field Operations Division (7506C), Office of
Pesticide Programs (OPP), US EPA, Washington, DC 20460, telephone
703-305-5805.

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     Following the comment period, the Tris(hydroxymethyl)nitromethane
RED document will be available from the National Technical Information
Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161, telephone
703-487-4650.
     For more information about EPA's pesticide reregistration program,
the Tris(hydroxymethyl)nitromethane RED, or reregistration of individual
products containing the active ingredient 2-(hydroxymethyl)-2-nitro-l,3-
propanediol, please contact the Special Review and Reregistration Division
(7508W), OPP, US EPA, Washington, DC 20460, telephone 703-
308-8000.
     For information about the health effects of pesticides,  or for assistance
in recognizing and managing pesticide poisoning symptoms, please contact
the National Pesticides Telecommunications Network (NPTN).  Call toll-
free 1-800-858-7378, between 8:00 am and 6:00 pm Central Time,  Monday
through Friday.

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