United States
Environmental Protection
Agency
Prevention, Pesticides
And Toxic Substances
(7508C)
EPA-738-F-98-015
December 1998
R.E.D. FACTS
Pesticide
Reregistration
Use Profile
Aluminum and Magnesium Phosphide
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 before November 1, 1984, 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. To implement the provisions of
the Food Quality Protection Act of 1996, EPA considers the special sensitivity
of infants and children to pesticides, as well as aggregate exposure of the
public to pesticide residues from all sources, and the cummulative effects of
pesticides and other compounds with common mechanisms of toxicity. The
Agency develops any mitigation measures or regulatory controls needed to
effectively reduce 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 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 cases
0025 & 0645, aluminum and magnesium phosphide.
Aluminum and magnesium phosphide are fumigants used to control
insects and rodents. They are primarily used for indoor fumigation of raw
agricultural commodities, animal feeds, processed food commodities, and non-
food commodities in sealed containers or structures, and for outdoor
fumigation of burrows to control rodents and moles in non-domestic areas,
noncropland, and agricultural areas. Aluminum and magnesium phosphide are
formulated as tablets, pellets, impregnated materials and dusts. Aluminum and
magnesium phosphide are restricted use chemicals. The use by certified
pesticide applicators with respect to rodent control for burrows at least fifteen
feet from a residential structure is considered a residential use.
Aluminum and magnesium phosphide react with moisture in the
atmosphere to produce phosphine gas which is the substance that is active as a
pesticide. For this reason, and given their common use sites and methods of
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application, the Agency is considering these two pesticides together for the
purposes of risk assessment and reregi strati on.
Regulatory
History
Aluminum Phosphide
Development of aluminum phosphide as a source of phosphine gas for
fumigation was pioneered by the German company Degesch. Aluminum
phosphide was first registered as a pesticide in the U.S. in 1958 to Hollywood
Termite Control Company, Inc. Although the registrant's name was changed
subsequently, the original U.S. aluminum phosphide registration remains
active. Currently there are 23 products containing aluminum phosphide as the
active ingredient registered as pesticides in the U.S. All of these aluminum
phosphide products have been classified as restricted use due to "Inhalation
Hazard to Humans" (40 CFR, §152.175).
In October of 1981, EPA issued a Pesticide Registration Standard which
discussed safety data and labeling for products containing aluminum
phosphide. EPA also issued a data call-in associated with the Registration
Standard for aluminum phosphide. Subsequently, EPA's Office of Pesticide
Programs issued PR Notice 84-5, a "LABEL IMPROVEMENT PROGRAM
FOR FUMIGANTS" and PR Notice 85-6, which partially revised PR Notice
84-5, but did not alter the portions of PR Notice 84-5 that pertained to
aluminum phosphide.
In February of 1986, EPA announced an "Amended Registration
Standard Process" for pesticides containing aluminum phosphide as the active
ingredient. That action was precipitated by the Agency's having completed
review of the data developed in response to the data call-in associated with the
1981 Registration Standard. In October of 1986, EPA announced another
"Amended Registration Standard Process" which was intended to supersede
the 1981 Registration Standard, PR Notices 84-5 and 85-6, and the amended
standard for aluminum phosphide issued earlier in 1986. The second amended
standard issued in 1986 required additional data submissions and labeling
changes for aluminum phosphide and magnesium phosphide products.
40 CFR §180.225 identifies tolerances in raw agricultural commodities
for residues of phosphine gas resulting from postharvest applications and
preharvest burrow treatments with aluminum phosphide. 40 CFR §185.200
and §186.200 identify tolerances in processed foods and animal feeds for
phosphine resulting from use of aluminum phosphide.
Magnesium Phosphide
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Magnesium phosphide was first registered as a pesticide in the U.S. in
1979. Currently, there are four pesticide products containing this active
ingredient registered in the U.S. All pesticide products containing magnesium
phosphide as an active ingredient have been classified as restricted use due to
"Inhalation Hazard to Humans" (40 CFR, §152.175).
In 1982, EPA announced a Registration Standard for magnesium
phosphide. PR Notice 84-5 included labeling statements that were to be
incorporated into the labeling of magnesium phosphide products. PR Notice
85-6 did not alter these statements.
In February of 1986, EPA announced an "Amended Registration
Standard Process" for Magnesium Phosphide. The "Amended Registration
Standard Process" of October 1986, which pertained to magnesium phosphide
as well as to aluminum phosphide, superseded the documents for the individual
chemicals issued earlier in the same year, and imposed additional data and
labeling requirements for both metallic phosphides.
40 CFR §180.375 identifies tolerances in raw agricultural commodities
for residues of phosphine gas resulting from postharvest applications and
preharvest burrow treatments with magnesium phosphide. 40 CFR §185.3800
and §186.3800 identify tolerances in processed foods and animal feeds for
phosphine resulting from use of magnesium phosphide.
Human Health
Assessment Toxicity
Aluminum and magnesium phosphide are in Toxicity Category I, the
highest (most toxic) of four categories, for acute effects via the inhalation
route. No significant exposure to phosphine gas is expected via the oral or
dermal routes. The Agency does not believe that aluminum and magnesium
phosphide pose a carcinogenic concern.
Dietary Exposure and Risk
The Chronic Reference Dose (RfD), the amount of pesticide that
could be consumed daily without causing adverse effects, for aluminum and
magnesium phosphide is 0.0113 mg/kg/day based on the threshold NOEL of
1.13 mg/kg/day in a 90-day inhalation study in rats. The Agency is using
inhalation data to establish dietary risk because the pesticide is a gas under
normal conditions and thus exposure is most likely to occur via the inhalation
route. Chronic non-cancer dietary risk is estimated to occupy less than nine
percent (9%) of the chronic RfD for the most sensitive sub-population. The
Acute Reference Dose for aluminum and magnesium phosphide is 0.018
mg/kg/day based on a lack of treatment-related effects after 15 days of
exposure in a 90-day inhalation study in rats. Acute dietary risk is estimated to
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occupy 27% of the acute RfD for the most sensitive sub-population. Since
residues of phosphine are not expected in drinking water, the aggregate
dietary risk for aluminum and magnesium phosphide to the general population
is based solely on risks from residues in food. Therefore the acute and chronic
aggregate risks are the same as those mentioned above for food. Hence,
significant concerns related to acute and chronic dietary exposure are not
predicted.
Occupational and Residential Exposure and Risk
The handler inhalation risk assessment based on study data for
fumigators, aerators and nearby persons indicates that short- and intermediate-
term inhalation risks are acceptable (i.e., Margins of Exposure (MOE) greater
than 100) if such handlers wear NIOSH-approved respiratory equipment (full-
face respirator or SCBA depending on the scenario) while performing
fumigation and aeration tasks. For nearly all scenarios and tasks, the risks are
unacceptable for handlers wearing baseline attire (i.e., no respiratory
protection). In addition to handlers, the Agency is concerned about the
potential risks posed to occupational and residential bystanders who are not
likely to be wearing the necessary respiratory protection. A number of
incidents have also been reviewed and are considered to lend additional
support to the Agency's risk concerns.
There is a limited registered residential use for rodent burrow treatment
at the present time. A quantitative risk assessment for this use has not been
conducted. However, the Agency has proposed that this use be removed.
FQPA Assessment
In accordance with the Food Quality Protection Act of 1996, the Agency
uses a weight-of-evidence approach to determine whether to retain, reduce, or
remove the 10X safety factor required for possible enhanced sensitivity to
infants and children. The available data provided no indication of increased
susceptibility of rats to in utero or postnatal exposure to aluminum or
magnesium phosphide. In addition, exposure assessments do not indicate a
concern for a potential risk to infants and children because residues of
phosphine are not expected in food or drinking water and there is currently
only a limited residential use. Given these factors, the Agency determined that
the 10X safety factor to account for increased sensitivity of infants and children
be removed based on an evaluation of the toxicology and exposure data.
Environmental
Assessment
Environmental Fate and Ecological Effects
Aluminum phosphide and magnesium phosphide appear to be non-
persistent under most environmental conditions, and are non-mobile in soil
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because of their instability at atmospheric moisture contents. Other products of
hydrolysis are aluminum and magnesium hydroxides. The aluminum and
magnesium hydroxide residues can further react to produce mineral phases that
are known to occur naturally in the environment. Inorganic phosphate and
other phosphorous oxyacids are expected to be other products formed from
the oxidation of phosphine gas in soils.
Under normal environmental conditions phosphine exists as a gas.
Phosphine in the atmosphere is rapidly degraded. The half-life in air is
approximately five hours with the mechanism of degradation being
photoreaction with hydroxy radicals. The dark half-life is approximately 28
hours. The expected reaction products of phosphine in air are oxyacids of
phosphorous and inorganic phosphate which are non-volatile.
Studies suggest that phosphine below the soil surface is quickly adsorbed
and degraded. The interaction of phosphine with soil appears to be mixed
chemisorption (irreversible) and physisorption (reversible), with the extent of
each dependent on soil type.
In summary, aluminum phosphide and magnesium phosphide are
expected to degrade rapidly in the environment to aluminum hydroxide and
magnesium hydroxide and phosphine, the toxicant of these pesticides. It
appears that phosphine will degrade in days and is at low risk for
contaminating ground or surface waters. Phosphine near the soil surface is
expected to diffuse into the atmosphere and be removed via photodegradation.
Phosphine trapped beneath the soil surface will bind to soil, inhibiting
movement, and be oxidized to phosphates.
Given the use patterns of the pesticides and these characteristics,
aluminum and magnesium phosphide are not expected to pose a significant
ecological risk to non-target organisms or to water resources under most
circumstances, with the notable exception of some endangered species that
may be found in burrows being treated with these chemicals.
Risk Mitigation As a result of this RED, the Agency does not have concerns relative to
dietary exposure (including food and water), for the general population, to
aluminum and magnesium phosphide. Given the high toxicity of aluminum and
magnesium phosphide and potential risks posed to occupational and residential
bystanders, a number of mitigation measures are being proposed by the
Agency. Since aluminum and magnesium phosphide have significant benefits
(protection of stored products and public health use) and there are few if any
viable alternatives, the Agency believes that it is important that a broad
stakeholder process be conducted to discuss these measures and/or to develop
other workable mitigation measures that adequately protect occupational and
residential bystanders. These proposals present the Agency's best attempt to
reduce the risks of concern. These measures are to be discussed as part of the
public review and stakeholder meeting process mentioned above. The
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proposals along with several questions for which the Agency would like
specific input are as follows:
I. Notification of Authorities and On-site Workers
The Agency believes that it is important that anyone who might be
expected to respond to an emergency involving aluminum an magnesium
phosphide be well prepared to quickly and effectively respond to such a
situation. Hence, the Agency is proposing that applicators would be
required to ensure that the local authorities (fire departments, police
departments etc.) are notified of the date, time, and location of planned
fumigation events at least 24 hours in advance of beginning operations.
Further, the Agency is concerned that on-site workers not directly
associated with the fumigation could be inadvertently exposed to
phosphine since they may frequent areas near fumigated structures. To
minimize the potential for inadvertent exposures the Agency is proposing
that the applicators would be required to notify any worker or other
person who might be expected to be in the proximity of the
fumigation/aeration, prior to fumigation.
* what authorities would need to be notified?
* who would be responsible for notification?
* what form or method of notification of both authorities and workers
should be employed?
* what is the appropriate timing for notifications?
ii. Requirement for Certified Applicators
The Agency believes that a properly structured certification
process provides for a high level of competence in those that are able to
complete this process. This level of competence could be difficult to
attain without completion of such a process. In order to better ensure
the safe conduct of fumigation/aeration operations, the Agency is
proposing to require that all persons who conduct these activities be a
certified applicator or that certified applicators supervising the activity be
within 50 ft of the operation and within clear sight-line of the persons
conducting the operation. Current labels allow for non-certified
fumigators and aerators to conduct activities under the direct supervision
and physical presence of a certified applicator. However, it is possible
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under this current language for the certified applicator to be a significant
distance away from the actual operation, impeding his/her ability to
adequately oversee the operations. This potential problem would be
solved by requiring certified applicators to be within 50 feet (and within
clear sight lines) of persons conducting fumigation/aeration operations.
* when a certified applicator is supervising an operation where
should he/she be positioned with respect to the work being done?
iii. Prohibit Aeration of Railcars, Railroad Boxcars, Other Vehicles,
and Containers En-Route.
The Agency is concerned about the possibility of exposure to
phosphine from aeration of fumigated railcars, railroad boxcars, shipping
containers, and other vehicles while in transit. This would especially be
of concern during scheduled and unscheduled stops in or near populated
areas. To ensure that these exposures do no occur, the Agency is
proposing that aeration of fumigated railcars, railroad boxcars, shipping
containers, and other vehicles while in transit would be prohibited.
Labels would be required to include this prohibition.
* what measures can be taken to prevent exposures from aeration
of fumigated railcars, railroad boxcars, shipping containers, and
other vehicles while in transit?
iv. Placarding fumigated structures, containers, and vehicles.
The Agency is concerned about potential exposure resulting from
improper entrance to fumigated vehicles that have been fumigated prior
to/during transit. While the labels require monitoring of such vehicles
prior to entry the labels are not always part of the shipment records and
the current placards do no necessarily contain this requirement. The
Agency also believes it is important that placards contain incident
reporting information so that those who might be exposed be better able
to report the incident. Currently, labels require the placarding of
structures, containers, and vehicles that have been fumigated. The
Agency is proposing as a possible requirement that these placards, or
some other documentation that accompanies the
structure/container/vehicle, clearly state that prior to entering the
structure/container/vehicle a certified applicator or trained person under
the supervision of a certified applicator (as defined above) must monitor
the concentration of phosphine therein. Unloading where exposure to
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workers or bystanders is possible, or entry must not occur until the
measured concentrations are below the pertinent standard unless
appropriate PPE is worn. These placards must also contain information
for reporting incidents which is consistent with the incident reporting
program developed by the registrants.
* how should information be provided to persons prior to entry
into a fumigated structure or vehicle to prevent exposure? What
should that information be?
* what is the appropriate mechanism for reporting incidents and
how should that mechanism be communicated?
v. Establish an Incident Reporting Program.
The Agency believes that, given the toxicity of these chemicals and
the incident data currently available, a structured program would need to
be developed to ensure that more complete and accurate information
regarding incidents is collected and analyzed. Therefore, the Agency is
proposing that registrants would be required to establish programs for
the comprehensive reporting of incidents to the Agency on an annual
basis.
* what mechanisms can be used to report and analyze incidents
involving aluminum and magnesium phosphide?
vi. Personal Protective Equipment
Given the high level of toxicity of phosphine and the Agency's
concerns regarding the potential for exposure as outlined in this RED,
the Agency is proposing to require that all persons involved in
fumigation/aeration operations wear respiratory protection during those
operations unless it can be verified via monitoring that the concentrations
of phosphine are at or below the established standard. PPE would be
required to be worn by any person conducting monitoring activities until
concentrations are known to be below the established limit. In the event
of a spill or leak, SCB A or supplied air would be required to be worn
until the spill has been cleaned or the leak has been repaired.
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As mentioned previously, a full face respirator is not always
adequately protective, and SCBA can be cumbersome and difficult to use
over extended periods of time. Supplied air is a possible alternative.
Supplied air is defined as a NIOSH-approved full-face or hood
respirator to which is supplied uncontaminated air, usually via a hose fed
by an electric compressor. The face piece or hood must be maintained
under positive pressure to maintain the maximum protection factor.
*what procedures could reduce the potential for exposure during
fumigation/aeration operations?
* what equipment would provide adequate protection under
various conditions?
vii. Proposal to require two-man operation for any activity that would
involve entry into a fumigated structure.
Due to the acutely toxic effects of inhaling phosphide gas the
Agency is proposing that a minimum of two qualified persons would be
needed to carry out any fumigation requiring entry into a structure. By
implementing a two-man rule, if an applicator is unable to remove
oneself from a dangerous exposure situation the second person can then
assist in the safe removal of that person from danger. One person would
be required to be a certified applicator and one person would need to be
trained in the use of monitoring equipment and the health effects of
phosphine gas. Although phosphine gas is considered to have good
'warning properties' because of a foul odor detectable by smell as low as
0.02 ppm, not all persons have the same sense of smell. Because some
persons may have a poor sense of smell, and due to the capacity for the
sense of smell to be fatigued after prolonged exposure, the fumigation
workers should rely upon chemical detecting instruments.
*what steps can be taken to ensure that an applicator is able to exit
a dangerous situation safely?
* what qualifications should the person who is acting as the second
person have?
viii. Establish 500 foot buffer zone and restricted area around all
fumigated structures
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The Agency is concerned about the possibility of bystander
exposure to phosphine especially in residential areas especially
considering the toxicity of phosphine. Based upon a review of incidents,
the Agency is proposing to prohibit the fumigation and aeration of
structures that are within 500 feet of residential areas. Further, a 500
foot restricted area would be implemented for all areas/structures
undergoing fumigation/aeration. These steps would be taken primarily
to prevent exposure to residential bystanders. Prior to entry to this area
monitoring would need to be conducted to ensure that the concentrations
of phosphine in the atmosphere is less than the 0.03 ppm standard
established in this RED or the limit of detection of the best available
technology. Entry would not allowed above that concentration unless
appropriate PPE is worn. Placarding would be required to occur around
the perimeter of the 500 foot restricted zone. Efforts would need to be
made to request permission for placarding where placarding of the
perimeter would involve other people's property.
* what size buffer zone, if any, would provide adequate protection
to residential bystanders?
* what alternative measures could be put in place to achieve
protection w/o a buffer zone?
* what would be the impact on the ability to fumigate various
structures if a 500 foot zone was put in place?
* what measures could be put in place regarding railcars, shipping
containers and other vehicles to prevent bystander exposure?
ix. Institute More Thorough Monitoring Around the Commodity
The Agency is concerned about the possibility of exposure
resulting from entry into a structure where phosphine gas pockets have
developed which normal monitoring would not detect. Therefore, the
Agency is proposing to require stringent monitoring when unloading or
otherwise disturbing a commodity that has been fumigated, since the
level of phosphine gas may be higher at the core of the commodity than
in the surrounding air. Monitoring at the door or hatch is insufficient in
some cases. Therefore, concentrations would be required to be
monitored at the top, middle, and bottom levels of the
commodity/storage facility, where feasible, because of stratification of
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gasses and vapors (similar to monitoring in confined spaces, OSHA 29
CFR 1910.146).
* what steps can be taken to ensure that there are not "pockets" of
phosphine gas within a given structure or commodity prior to
entry?
* what are the technical limitations to conducting this type of
monitoring, if any?
x. Require Seal/Leak Testing for Fumigated Structures
The Agency believes that one potential exposure scenario would
involve leakage of phosphine, especially into adjacent structures where
people may be working/residing. For this reason the Agency is
proposing that, prior to fumigation, the structure would undergo
seal/leak testing using established methods to ensure that leakage during
fumigation will not occur or is significantly minimized. Record of
seal/leak tests must be retained by the certified applicator. Leaks would
need to be repaired prior to fumigation. Fumigation would prohibited in
cases where substantial leaks are discovered and cannot be sealed.
* what methods are available for conducting effective leak tests
and how costly are these methods?
* what other steps could be taken to reduce the possibility of
significant leaks?
* how can substantial leakage be defined?
xi. Establish a Minimum Distance from Residences for Burrow Use
and PPE for Applicators During these Applications.
The Agency is concerned about the possibility of unintended
exposure to residents or other bystanders that might result from rodent
control uses near homes or other commercial facilities such as hospitals,
schools, and nursing homes. Therefore, the Agency is proposing that
treatment of burrows for rodent control be prohibited within 100 feet of
a residence. Note that current labels have a restriction of 15 feet, which
may not be protective if burrow tunnels extend toward residences
(basements). Applicators involved in the fumigation of animal burrows
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would be required wear respiratory protection during the course of the
operation. These actions would eliminate the residential uses of
aluminum and magnesium phosphide but would allow for rodent control
to continue under other circumstances. In cases of public health, where
no other alternatives can be found, exceptions to this item may be made.
* how can exposures to bystanders be prevents when burrows are
treated in a residential or school/hospital setting?
* what, if any, size buffer zone around residential and other related
structures would provide adequate protection from inadvertent
exposure?
* what is the potential for seepage of phosphine into basements
during a burrow treatment?
xii. Notification of Local Residents
The Agency believes that it is important to notify local residents
near fumigated structures so that they can take actions if they choose to
protect themselves from possible phosphine exposure. This is especially
germane given the Agency's commitment to community right to know.
Therefore, the Agency is proposing to require notification so that
residents in adjoining properties can make decisions regarding
temporarily leaving their property during fumigation. Such notification
would also be required for commercial and industrial sites that are near a
planned fumigation operation. The Agency proposes that the certified
applicator would be required to ensure that all residents are notified
within 750 feet of the fumigated structure.
* what is the most appropriate means of informing the public of
impending fumigation\aeration operations?
* how should the local area be defined for purposes of
notification? Is 750 ft. appropriate?
xiii. Requirement for Improved Training for Certified Applicators
The Agency believes that effective training and certification
programs are needed to ensure that applicators are prepared to conduct
fumigation operations safety. Since fumigation is a relatively unique
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operation when compared to other agricultural and non-agricultural pest
control practices, the Agency believes that a fumigation-specific
certification program may be necessary. Although current labels state
the need for applicators to have training in phosphine fumigation,
existing training programs appear insufficient given the high incident
rate. The Agency is proposing to require that the registrants work with
the appropriate personnel in the Agency and in the States to develop a
fumigator-specific certification program that adequately addresses all
risks associated with the use of these chemicals. These programs would
stress the highly toxic nature of the chemicals, fumigation/aeration-
specific issues, and the importance of understanding and following label
language exactly. Also, those requirements that result from the
outcomes of the stakeholder meetings, must be emphasized. This effort
would also include consideration of the most effective method of
delivering this training.
* ;
is there a need for a fumigation-specific training program?
* what elements should a fumigation-specific certification program
contain?
* could existing programs be improved upon to meet these needs
or does a new program need to be developed?
* can reciprocity or standardization be achieved? should they be
achieved?
xiv. Monitoring Methods to Minimize Exposure
The Agency is concerned about exposures to phosphine given its
high toxicity. Therefore, the Agency is proposing to require additional
monitoring of areas around fumigated structures in order to reduce the
potential for occupational and residential bystander exposure to
phosphine. The Agency is further proposing to require that no fumigated
structure be entered until it can be verified that the concentrations of
phosphine present are at or below the 0.03 ppm standard unless
appropriate PPE is worn. A certified applicator or other competent
person (industrial hygienist etc.) Would be required to conduct the
monitoring. All fumigation/aeration operations would be covered by this
requirement including outdoor operations.
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The Agency recognizes that current technology may not be capable
of detecting phosphine at the 0.03 ppm level. Therefore, the best
available technology would be used with the limit of detection acting as
the standard until new technology becomes available at which time the
0.03 standard would be required. The Agency is aware of a "real-time"
direct-read device technologies with a limit of detection of 0.05 ppm that
are currently available. These devices can be equipped with audible
alarms and data loggers.
Further, there is evidence that the human sense of smell can
"detect" phosphine at 0.02 ppm levels (See also ix). In cases where an
employee smells the gas it will be assumed that the concentrations are
above the standard and proper precautions/actions taken. Under no
circumstances should a person consider smell as a monitoring option in
lieu of device monitoring.
* what are the impacts of using the .03 ppm regulatory standard?
* are there scientifically valid alternatives to the .03 ppm standard?
* what would an appropriate monitoring scheme include?
* is it appropriate to monitor "outdoor" operations? why or why
not?
xv. Establish and Define Applicable Exposure Limits for the Label
The Agency believes that it is important that users of this pesticide
be aware of all applicable workplace standards regarding phosphine.
Therefore, the Agency is proposing to require that these standards
appear on the label. It would be clearly stated that actions that are
required currently based upon the OSHA PEL, STEL and action levels
will now be required to occur based upon the 0.03 ppm standard
established by this document.
* same questions as above.
Additional Data
Required The Agency is requiring the submission of a two-year chronic
toxicity/carcinogenicity study as confirmatory data. This study is in progress
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and interim data have been provided to the Agency. The Agency is also
requiring a monitoring study. The monitoring data being requested must be
captured for all of the phases of fumigation: application; fumigation; and
aeration. The exposure levels of the applicator and assistants to phosphine
during each of these phases need to be documented. In addition, ambient air
concentrations in the immediate vicinity, i.e., where other personnel are
working, must be documented during each phase. Further, phosphine
concentrations must be measured to the limit of detection outside of the
structure to 500 feet away during each phase of fumigation. In addition,
product-specific data including product chemistry, revised Confidential
Statements of Formula (CSFs), and revised labeling for reregistration are being
required.
Product Labeling
Changes Required No labeling changes are being required at this time. Following the completion
of the stakeholder process, the Agency will develop the required label changes
resulting from that process.
Regulatory
Conclusion
Based on the reviews of the generic data for the active ingredients
aluminum and magnesium phosphide, the Agency has sufficient information on
the health effects of aluminum and magnesium phosphide and on their potential
for causing adverse effects in fish and wildlife and the environment. The
Agency has identified risks that must be reduced in order for these chemicals
to become eligible for reregistration. The Agency will conduct a public review
process to identify the best ways to reduce the risks associated with aluminum
and magnesium phosphide. This process will include a public comment period
and a stakeholder meeting(s), as well as consultation with the USDA's
Phosphine Task Force. At the conclusion of this process, the Agency will
make a final determination on the reregistration eligibility of aluminum and
magnesium phosphide. If found to be eligible, the Agency will specify the
requirements for reregistration.
For More
Information
EPA is requesting public comments on the Reregistration Eligibility
Decision (RED) document for aluminum and magnesium phosphide 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, Information and Record
Integrity Branch, Information Resources Services Division (7502C), Office of
Pesticide Programs (OPP), US EPA, Washington, DC 20460, telephone 703-
305-5805.
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Electronic copies of the RED and this fact sheet can be downloaded
from the Internet using WWW (World Wide Web) on
HTTP://WWW.EPA.GOV/REDs and requires adobe acrobat or compatible
reader.
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 1-800-
490-9198 or 513-489-8190, fax 513-489-8695.
Following the comment period, the aluminum and magnesium phosphide
RED document also will be available from the National Technical Information
Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161, telephone 1-
800-553-6847 or 703-605-6000.
For more information about EPA's pesticide reregi strati on program, the
aluminum and magnesium phosphide RED, or reregi strati on of individual
products containing aluminum and magnesium phosphide, please contact the
Special Review and Reregi strati on Division (7508C), 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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