United States Prevention, Pesticides EPA-738-F-97-004
Environmental Protection And Toxic Substances April 1997
Agency (7508W)
R.E.D. FACTS
1,3,5-Triethylhexahydro-
s-triazine
PGStJCJdG All pesticides sold or distributed in the United States must be
R0TGClistration 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 before November 1, 1984, be reregistered to ensure
that they meet today's more stringent standards.
Under the Food Quality Protection Act of 1996, EPA must consider
the increased susceptibility of infants and children to pesticide residues in
food, as well as aggregate exposure of the public to pesticide residues from
all sources, and the cumulative effects of pesticides and other compounds
with a common mechanism of toxicity in establishing and reassessing
tolerances.
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 develops
any mitigation measures or regulatory controls needed to effectively reduce
each pesticide's risks. EPA then reregisters pesticides that met the safety
standard of FQPA and can be used without posing unreasonable risks to
human health or the environment.
When a pesticide is eligible for reregistration, EPA explains the basis
for its decision in a Reregistration Eligibility Decision (RED) document.
This fact sheet summarizes the information in the RED document for
reregistration case 3147, 1,3,5-triethylhexahydro-s-triazine.
USG ProfilG 1,3,5-Triethylhexahydro-s-triazine, or triethylhexahydrotriazine is an
antimicrobial used as an industrial preservative treatment to control slime-
forming bacteria and fungi in adhesives, fuels, oil storage tanks, metal-
working cutting fluids, paints, slurries, rubber products, and industrial
processing chemicals. Formulations include liquid soluble concentrates.
Triethylhexahydrotriazine is added to industrial products using open-pouring
or metering pump methods.
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Regulatory
History
Human Health
Assessment
Triethylhexahydrotriazine was first registered for use as a
microbiocide and bacteriostat in the U.S. in 1967. In 1987 the Agency
issued the Antimicrobial Data Call-In Notice to obtain additional data for
this and other antimicrobial chemicals. Another Data Call-In Notice was
issued in September 1992 requiring additional toxicity and ecological effects
data in support of reregistration. Currently, two triethylhexahydrotriazine
products are eligible for reregistration.
Toxicity
In studies using laboratory animals, triethylhexahydrotriazine has been
shown to be somewhat acutely toxic via the oral and inhalation routes and
has been placed in Toxicity Category II (the second highest of four
categories) for these effects. Because of its corrosivity, acute dermal
toxicity and primary eye and skin irritation studies were waived, and
triethylhexahydrotriazine has been placed in Toxicity Category I (the highest
of four categories) for these effects.
In a dermal sensitization study with guinea pigs, triethyl-
hexahydrotriazine was not a skin sensitizer. As for mutagenicity, although
in vitro mutagenicity data indicate that it is mutagenic, negative in vivo
data suggest that triethylhexahydrotriazine lacks mutagenic potential.
For short-term (1-7 days) and intermediate-term (1 week-several
months) occupational and residential risk assessments, the Agency has
chosen the 75 mg/kg/day NOEL (for both maternal and developmental
toxicity) from a rat developmental toxicity study. In a sub-chronic dermal
study in rats, no systemic effects were observed at any dose level.
Consistent with current data requirements for non-food use chemicals, no
chronic toxicity data have been required for triethylhexahydrotriazine.
Even though chronic occupational exposure is possible with the use of
triethylhexahydrotriazine, chronic testing for cancer and other long term
effects is not required since EPA does not believe that chronic exposure
would result in a risk of concern.
Dietary Exposure
Current uses of triethylhexahydrotriazine do not include any food or
feed uses. Therefore dietary exposure is not anticipated and no dietary risk
assessments have been conducted.
Occupational and Residential Exposure
Based on current use patterns, EPA has determined that there is a
potential for exposure of mixers, loaders, applicators, and other handlers to
triethylhexahydrotriazine and its break-down product, formaldehyde, during
and after normal use of the pesticide in both occupational and residential
settings. EPA conducted assessments for dermal exposure only. The
Agency believes that inhalation exposure may also be a significant
component of overall exposure to triethylhexahydrotriazine because of its
high vapor pressure, particularly when triethylhexahydrotriazine-containing
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paint is used. At this time, however, EPA has no data with which to
conduct an inhalation exposure and risk assessment. Thus, the Agency is
requiring handler and post-application inhalation exposure data.
Human Risk Assessment
As mentioned previously, triethylhexahydrotriazine is so corrosive that
the dermal acute toxicity and primary skin and eye irritation studies were
waived. The Agency expects that concentrated triethyl-hexahydrotriazine
products may pose significant handler risk due to this corrosivity. The
Agency is addressing these risks through the establishment of PPE
requirements that are to be included on the labeling of all end-use products
that are classified as toxicity category I or II for skin or eye irritation
potential.
EPA is generally not concerned with occupational and residential risk
if MOEs (margins of exposure) are greater than 100. For triethyl-
hexahydrotriazine, all of the primary application (occupational) dermal
MOEs are greater than 100; they range from approximately 2,100 for
exposure in wet-end additives/industrial processing chemicals using a pump
metering system, to approximately 21,000 for open-pour operations during
paint, adhesive, and rubber manufacturing and in uses for fuels/oil storage
tank bottom water. For secondary exposure, such as applying paint
containing triethylhexahydrotriazine, dermal MOEs range from greater than
300 for occupational workers to greater than 1600 for residential
applicators.
EPA has also considered the potential hazard of exposure to
formaldehyde, a degradate of triethylhexahydrotriazine. The Occupational
Safety and Health Administration (OSHA) has a comprehensive workplace
standard for formaldehyde to protect workers in occupational settings.
Residential and other non-occupational exposure to formaldehyde is
expected to be very low. However, the Agency will require confirmatory
exposure data that includes monitoring for formaldehyde during and after
application.
Other Considerations
Because triethylhexahydrotriazine currently has no food uses and no
tolerances have been established, the specific determinations outlined in the
Food Quality Protection Act of 1996 are not required for this chemical.
Nevertheless, EPA believes that consideration of available data relating to
the special sensitivity of infants and children, as well as the potential for
aggregate exposures and cumulative effects is prudent for
triethylhexahydrotriazine because children and other individuals could be
exposed to this compound in non-occupational settings.
Nothing in the available toxicity data base indicates special
susceptibility of infants and children to triethylhexahydrotriazine and,
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Environmental
Assessment
therefore, the Agency has concluded that an additional uncertainty factor for
estimating risk to young organisms is not warranted.
All products containing triethylhexahydrotriazine have primarily
indoor, non-food uses. Based on the available exposure information and
current use patterns, EPA does not anticipate exposure to residues of
triethylhexahydrotriazine in food or drinking water. Thus, the only non-
occupational exposure to triethylhexahydrotriazine would be from uses in
and around the home. Among these, applying paint would yield the greatest
potential exposure. Because the dermal MOE for this reasonable worst case
exposure is high (> 1600), EPA believes that aggregate exposures from
other sources of triethylhexahydrotriazine in the home are not likely to be of
concern.
The Agency has not yet made a determination regarding the common
mode/mechanism of toxicity of triethylhexahydrotriazine and whether it is
appropriate to consider exposure from triethyl-hexahydrotriazine with other
compounds in order to address potential cumulative effects. However,
based on the high dermal MOE for homeowner applicators, the lack of food
uses, the unlikelihood of residues in drinking water, and the low
concentration in paint, the Agency believes that the contribution of
triethylhexahydrotriazine exposure to the risks of other chemicals with a
common mode/mechanism of toxicity is likely to be minimal.
Environmental Fate
EPA requires only a hydrolysis study to characterize the
environmental fate of triethylhexahydrotriazine, due to its current use
patterns. EPA does not have a hydrolysis study for this active ingredient,
but, based on the behavior of structurally related chemicals, the expected
reaction products are formaldehyde and ethylamine. However, the effect of
different pHs on the rate of hydrolytic degradation is not known. Since the
data requirement is not fulfilled, EPA is requiring confirmatory hydrolysis
data on the rate of hydrolysis of triethylhexahydrotriazine at pH 5,7, and 9,
and the reaction products must be identified.
Ecological Effects
Triethylhexahydrotriazine is slightly to moderately toxic to birds on an
acute basis and practically non-toxic on a subacute basis. It demonstrates
slight toxicity to both cold and warm freshwater fish, and is slightly toxic to
freshwater invertebrates on an acute basis.
Ecological Effects Risk Assessment
The Agency requires only a limited number of ecotoxicology and
environmental fate studies for microbiocides with primarily indoor use
patterns. While the hazard to aquatic organisms from
triethylhexahydrotriazine has been characterized, a quantitative risk
assessment has not been conducted. The risks to aquatic environments are
regulated under the National Pollutant Discharge Elimination System
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Risk Mitigation
Additional Data
Required
(NPDES) permitting program of the Agency's Office of Water. EPA does
not anticipate any exposure of concern to fish or wildlife, providing that all
triethylhexahydrotriazine products are handled and applied as specified in
the product labeling, and discharges to the environment comply with all
federal disposal laws and the NPDES program.
To lessen the potential risks posed by triethylhexahydrotriazine and
products treated with triethylhexahydrotriazine, EPA is requiring the
following risk mitigation measures.
• EPA requires that handlers using occupational-use products wear long-
sleeve shirts, long pants, shoes, and socks as minimum work attire.
Further handler safety requirements for products containing
triethylhexahydrotriazine will be determined based on the acute toxicity
characteristics of the end-use product.
• EPA is requiring the use of meter pumps or other automatic
dispensing equipment for triethylhexahydrotriazine use in wet-end additives
and industrial processing chemicals.
• For use in paint, rubber products, industrial adhesives, or fuel/oil
storage tank bottoms, EPA is requiring that the vats to which the
triethylhexahydrotriazine is added must be closed and equipped with
mechanical vents to the outdoors.
• EPA is requiring NPDES permits for discharge of triethylhexa-
hydrotriazine effluent.
To confirm its regulatory conclusions on triethylhexahydrotriazine,
EPA is requiring additional generic data to assess hydrolysis. Additionally,
the Agency will require exposure data from paint applications by brush,
roller, and sprayer, as well as post application monitoring data to determine
exposure to residents or occupants of areas that have been painted. These
post application data will include monitoring for degradates. Because much
of the exposure data needed for triethylhexahydrotriazine is generic in
nature and will also be required for other antimicrobial chemicals with
similar characteristics and uses, EPA is developing a generic exposure DCI
for antimicrobials. Triethylhexahydrotriazine registrants will receive the
generic antimicrobial exposure DCI at the same time as registrants of other
antimicrobial chemicals with similar uses.
Product Labeling
Changes
Required
All triethylhexahydrotriazine end-use products must comply with
EPA's current pesticide product labeling requirements and with the
following.
• Minimum (Baseline) PPE/Engineering Control Requirements
Any necessary PPE for each triethylhexahydrotriazine occupational
end-use product will be established on the basis of the end-use
product's acute toxicity category as specified in Section V of the RED
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document. All end-use products will be required to specify the
minimum work attire for all handlers.
The minimum handler work attire labeling requirement for
occupational uses of triethylhexahydrotriazine end-use products is:
"Mixers, loaders, applicators and other handlers must wear:
— Long-sleeve shirt and long pants,
— Shoes plus socks."
If the end-use product is classified as toxicity category I or II for eye
irritation potential or if data for this route of concern are waived due
to corrosivity, add:
— Protective eyewear.
If the end-use product is classified as toxicity category I or II for acute
dermal toxicity or skin irritation potential or data for either of these
routes of concern are waived due to corrosivity, add:
— Chemical-resistant apron, and
— Chemical-resistant gloves*.
'For the glove statement, use the statement established for triethylhexahydrotriazine
through the instructions in Supplement Three of PR Notice 93-7. In addition, for
concentrated triethylhexahydrotriazine products, the corrosiveness and penetration of
triethylhexahydrotriazine must be considered. Appropriate chemical-resistant materials
must be listed on the product labeling.
If the end-use product is classified as toxicity category I or II for acute
inhalation toxicity, a respirator requirement must be added. The type
of respirator must be specified in the statement and is based on the
acute toxicity category and the vapor pressure. EPA will assist
registrants in determining the appropriate type of respirator during the
end-use product phase of reregistration.
In addition to the minimum PPE specified above, the following
specific PPE and engineering-control requirements must be added to
labels containing the following uses.
When labeling contains uses for wet-end additives/industrial
processing chemicals, add the following:
"For use in wet-end additives/industrial processing chemicals,
meter pumps or other automatic dispensing equipment is
required. Open pouring is prohibited."
When labeling contains uses for paint, rubber products, or industrial
adhesives, or fuels/oil storage tank bottom water, add the following:
"For use in paint, rubber products, industrial adhesives, or
fuels/oil storage tank bottom water, the vats to which
triethylhexahydrotriazine is being added must be closed and
equipped with mechanical vents to the outdoors."
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Placement in Labeling
The personal protective equipment requirements must be placed on the
end-use product labeling in the format and language specified above
and must be placed in the "Hazards to Humans" section of the
pesticide labeling.
Other Labeling Requirements - Products Intended for
Occupational Use
The Agency is requiring the following labeling statements to be
located on all end-use products containing triethylhexahydrotriazine
that are intended primarily for occupational use. Additional handler
safety requirements will be determined based on the acute toxicity
characteristics of each end-use product.
Application Restrictions
"Do not use this product in a way that will contact workers or
other persons."
"Do not apply this product as a spray."
User Safety Requirements
If gloves or protective eyewear are required PPE on the end-use
product, add:
"Follow manufacturer's instructions for cleaning/maintaining
PPE. If no such instructions are provided for washables, use
detergent and hot water. Keep and wash PPE separately from
other laundry."
User Safety Recommendations
"Users should wash hands before eating, drinking, chewing
gum, using tobacco, or using the toilet."
"Users should remove clothing immediately if pesticide gets
inside. Then wash thoroughly and put on clean clothing."
Registrants must add the following statements only if gloves are
required PPE on the end-use product:
"Users should remove PPE immediately after handling this
product. Wash the outside of gloves before removing. As soon
as possible, wash thoroughly."
RGQLllatory The use of eligible triethylhexahydrotriazine products in accordance
Conclusion w^n Deling specified in this RED will not pose unreasonable adverse
effects to humans or the environment. These products will be reregistered
once the required confirmatory generic data, product specific data, revised
Confidential Statements of Formula (CSFs), and revised labeling are
received and accepted by EPA.
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For More
Information
EPA is requesting public comments on the Reregistration Eligibility
Decision (RED) document for triethylhexahydrotriazine 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.
Electronic copies of the RED and this fact sheet can be downloaded
from the Pesticide Special Review and Reregistration Information System at
703-308-7224. They also are available on the Internet by using ftp on
FTP.EPA.GOV, or using WWW (World Wide Web) on WWW.EPA.GOV.
Printed copies of the RED and fact sheet can be obtained from EPA's
National Center for Environmental Publications and Information
(EPA/NCEPI), PO Box 42419, Cincinnati, OH 45242-0419, telephone
513-489-8190, fax 513-489-8695.
Following the comment period, the triethylhexahydrotriazine RED
document also 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 1,3,5-triethylhexahydro-s-triazine RED, or reregistration of individual
products containing triethylhexahydrotriazine, 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 9:30 am and 7:30 pm Eastern Standard
Time, Monday through Friday.
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