US Environmental Protection Agency
Office of Pesticide Programs
Reregistration Eligibility Decision (RED)
for Dazomet
July 9, 2008
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United States Prevention, Pesticides EPA 738-R-08-007
Environmental Protection and Toxic Substances July 2008
Agency (7508P)
Reregistration Eligibility Decision
for Dazomet
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Dazomet RED
ListB
Case No. 2135
Approved by:
Steven Bradbury, Director
Special Review and Reregistration Division
Date:
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Glossary of Terms and Abbreviations
AGDCI
ai
aPAD
BCF
CFR
cPAD
CSF
CSFII
DCI
DEEM
DFR
DNT
EC
EDWC
EEC
EPA
EUP
FDA
FIFRA
FFDCA
FQPA
GLN
IR
LD,
'50
LOC
LOAEL
MATC
mg/kg/day
mg/L
MOE
MRID
MUP
NOAEL
Agricultural Data Call-In
Active Ingredient
Acute Population Adjusted Dose
Bioconcentration Factor
Code of Federal Regulations
Chronic Population Adjusted Dose
Confidential Statement of Formulation
USDA Continuing Surveys for Food Intake by Individuals
Data Call-In
Dietary Exposure Evaluation Model
Dislodgeable Foliar Residue
Developmental Neurotoxicity
Emulsifiable Concentrate Formulation
Estimated Drinking Water Concentration
Estimated Environmental Concentration
Environmental Protection Agency
End-Use Product
Food and Drug Administration
Federal Insecticide, Fungicide, and Rodenticide Act
Federal Food, Drug, and Cosmetic Act
Food Quality Protection Act
Guideline Number
Index Reservoir
Median Lethal Concentration. A statistically derived concentration of a
substance that can be expected to cause death in 50% of test animals. It is
usually expressed as the weight of a substance per weight or volume of
water, air, or feed, e.g., mg/1, mg/kg, or ppm.
Median Lethal Dose. A statistically derived single dose that can be
expected to cause death in 50% of the test animals when administered by
the route indicated (oral, dermal, inhalation). It is expressed as a weight
of substance per unit weight of animal, e.g., mg/kg.
Level of Concern
Lowest Observed Adverse Effect Level
Maximum Acceptable Toxicant Concentration
Micrograms Per Gram
Micrograms Per Liter
Milligram Per Kilogram Per Day
Milligram Per Liter
Margin of Exposure
Master Record Identification Number. EPA's system for recording and
tracking studies submitted.
Manufacturing-Use Product
No Observed Adverse Effect Level
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OPP
OPPTS
PAD
PCA
PDF
PHED
PHI
ppb
PPE
ppm
PRZM/EXAMS
RAC
RED
REI
RfD
RQ
SCI-GROW
SAP
SF
SLC
TGAI
USDA
USGS
UF
UV
WPS
EPA Office of Pesticide Programs
EPA Office of Prevention, Pesticides, and Toxic Substances
Population Adjusted Dose
Percent Crop Area
USDA Pesticide Data Program
Pesticide Handler's Exposure Data
Pre-harvest Interval
Parts Per Billion
Personal Protective Equipment
Parts Per Million
Tier II Surface Water Computer Model
Raw Agriculture Commodity
Reregi strati on Eligibility Decision
Restricted Entry Interval
Reference Dose
Risk Quotient
Tier I Ground Water Computer Model
Science Advisory Panel
Safety Factor
Single Layer Clothing
Technical Grade Active Ingredient
United States Department of Agriculture
United States Geological Survey
Uncertainty Factor
Ultraviolet
Worker Protection Standard
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Table of Contents
Abstract 8
I. Introduction 9
II. Chemical Overview 9
A. Chemical Identity 9
B. Use and Usage Profile 10
C. Regulatory History 12
III. Dazomet Risk Assessments 12
A. General Overview of Soil Fumigants 12
1. Human Health Risk 12
2. Environmental Fate, Ecological Effects and Risk 15
3. Benefits 17
B. Antimicrobial Risk 18
IV. Risk Management and Reregi strati on Decision 19
A. Determination of Reregistration Eligibility 19
B. Public Comments and Responses 20
C. Regulatory Position 21
1. Regulatory Rationale 21
a. Dazomet Soil Uses 21
i. Rate Reduction and Use Sites 22
ii. Human Health Risk Management 22
aa. Bystander Risk Mitigation 23
1. Buffer Zones 24
2. Posting 37
bb. Occupational Risk Mitigation 40
1. Handler Definition 40
2. Handler Requirements 40
3. Dermal Protection for Handlers 41
4. Respiratory Protection for Handlers 41
5. Tarp perforation and removal 44
6. Entry Prohibitions 45
cc. Other Risk Mitigation 49
1. Restricted Use Classification 49
2. Good Agricultural Practices 50
3. Fumigant Management Plans (FMPs) 51
4. Emergency Preparedness and Response 55
5. Notice to State Lead Agencies 60
6. Soil Fumigation Training for Applicators and Other Handlers 60
7. Community Outreach and Education Programs 64
iii. Environmental Risk Management 65
b. Dazomet Antimicrobial Uses 66
2. Endocrine Disrupter Effects 67
3. Endangered Species Considerations 67
D. Conclusion 68
V. What Registrants Need to Do 69
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A. Manufacturing Use Products 70
1. Additional Generic Data Requirements 70
2. Labeling for Manufacturing-Use Products 75
B. End-Use Products 76
1. Additional Product-Specific Data Requirements 76
2. Labeling for End-Use Products 76
Appendix A(l): Dazomet (PC Code 035602) Soil Fumigant Uses Eligible for Reregi strati on. 103
Appendix A(2): Dazomet (PC Code 035602) Antimicrobial Uses Eligible for Reregi strati on . 103
Appendix B. Table of Generic Data Requirements and Studies Used to Make the Reregjstration Decision. ..Ill
Appendix C. Technical Support Documents 112
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Dazomet Reregistration Eligibility Decision Team
Office of Pesticide Programs:
Health Effects Risk Assessment
Charles Smith, Risk Assessor
Anna Lowit, Toxicology
Sherri Kinard, Residue Chemistry
Ruth Allen, Epidemiology
Judy Facey, Toxicology
Biological and Economic Analysis Assessment
TJ Wyatt, Senior Agricultural Economist
Jonathan Becker, Senior Science Advisor
Bill Chism, Senior Agronomist
David Donaldson, Agricultural Economist, Team Leader
Colwell Cook, Entomologist
Nicole Zinn, Biologist
Stephen Smearman, Economist
Leonard Yourman, Plant Pathologist
John Faulkner, Economist
Environmental Fate and Effects Risk Assessment
Mah Shamim, Branch Chief
FaruqueKhan, Senior Fate Scientist
James Felkel, Wildlife Biologist
Gabriel Rothman, Environmental Scientist
Registration Support
Mary Waller, Product Manager
Tamue Gibson, Product Reviewer
Kathy Monk, Senior Advisor
Antimicrobial Risk Assessment Team
Heather Garvie, Chemical Review Manager
Diane Isbell, Reregistration Team Leader
Cassi Walls, Ph.D., Chemist
Timothy Dole, Industrial Hygienist
Rick Petrie, Senior Agronomist, Team Leader
Risk Management - Soil Uses
Nikhil Mallampalli, Team Leader
Dirk Helder, Team Leader
Cathryn O'Connell, Chemical Review Manager
Office of General Council:
Andrea Medici
Office of Enforcement and Compliance:
David Stangel
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Abstract
This document presents the Environmental Protection Agency's (hereafter referred to as
EPA or the Agency) decision regarding the reregi strati on eligibility of the registered soil and
antimicrobial uses of dazomet. The Agency has determined that products containing dazomet for
these uses are eligible for reregistration provided that: (1) current data gaps are addressed; (2) the
risk mitigation measures identified in the document are adopted; and (3) labels are amended to
implement these measures.
Generally, registered dazomet uses fall into two basic categories, soil fumigation or
antimicrobial use. Soil fumigation includes use on golf greens or tees, nonbearing crops, turf
sites, ornamental sites, field nurseries, compost piles, potting soils, and strawberries and
tomatoes in California only. Antimicrobial uses include: 1) as a treatment during the production
of pulp and paper; 2) as a material preservative treatment for coatings, adhesives, epoxy flooring
compounds, slurries, and high viscous suspensions; 3) as a biocide treatment used during
petroleum operations; 4) as a biocide treatment to recirculating cooling water systems; and 5) as
a remedial wood treatment to utility poles.
Concurrent to EPA's review of the soil fumigant uses of dazomet, EPA assessed the risks
and developed risk management decisions for four other soil fumigant pesticides, including:
chloropicrin, metam sodium/potassium, methyl bromide, and a new active ingredient,
iodomethane. Risks of a fifth soil fumigant, 1,3-dichloropropene (1,3-D), were also analyzed
along with the other soil fumigants for comparative purposes; its risk management decision was
completed in 1998. The Agency evaluated these soil fumigants concurrently to ensure that
human health risk assessment approaches are consistent, and that risk tradeoffs and potential
economic impacts were considered appropriately in reaching risk management decisions. This
review is part of EPA's program to ensure that all pesticides meet current health and safety
standards.
EPA has identified potential human health risks of concern associated with the registered
soil fumigant uses of dazomet from acute inhalation exposure to handlers, bystanders, and
workers. To reduce these exposures and to address risks of concern, EPA is requiring a number
of mitigation measures, such as buffer zones, posting, handler protection, restrictions on the
timing of tarp perforation and removal operations, extending the entry prohibitions, restricted use
classification (for soil uses only), mandatory good agricultural practices (GAPs), site-specific
fumigant management plans (FMPs), emergency preparedness and response, notice to state and
tribal lead agencies, training for applicators and handlers, and required community outreach and
education programs. In addition the registrants have agreed to reduce the maximum rate from
530 Ibs ai/A to 425 Ibs ai/A which will directly reduce the potential risks to both humans and
non-target organisms. The ecological risk assessment identified potential acute risks of concern
for birds and mammals that could be exposed to unincorporated dazomet granules.
The Agency also has identified potential human health risks of concern associated with
the registered antimicrobial uses of dazomet. To reduce these exposures, the Agency is requiring
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a number of mitigation measures, including additional PPE for handlers engaged in these
applications: pulp and paper use, cooling tower use, and metering pumps. For the epoxy flooring
uses, the labels must be amended to reduce the amount of dazomet formulated in end use
products.
The Agency is issuing this decision document for dazomet, as announced in a Notice of
Availability published in the Federal Register. Due to the broad scope of the decision for the soil
fumigant group, there will be a 60-day public comment period for this document to allow
stakeholders the opportunity to review and provide comments on issues related to the
implementation of the risk mitigation measures.
I. Introduction
The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) was amended in 1988
to accelerate the reregistration of products with active ingredients registered prior to November
1, 1984. The amended Act calls for the development and submission of data to support the
reregistration of an active ingredient, as well as EPA's review of all submitted data.
Reregistration involves a thorough review of the scientific database underlying a pesticide's
registration. The purpose of the Agency's review is to reassess the potential risks arising from
the currently registered uses of the pesticide; to determine the need for additional data on health
and environmental effects; and to determine whether or not the pesticide meets the "no
unreasonable adverse effects" criteria of FIFRA.
This document presents the EPA decision regarding the reregistration eligibility of the
registered uses of dazomet. Dazomet is used as a non-selective soil fumigant with fungicidal,
herbicidal, and nematicidal properties. It is also used as an algaecide, bacteriostat, fungicide,
microbiocide, mildewcide in a number of antimicrobial use sites. When dazomet is applied, it is
quickly broken down into several degradates; the major degradate being methyl isothiocyanate
(MITC). The Agency made its reregistration eligibility determination based on the required
data, the current guidelines for conducting acceptable studies to generate such data, and
published scientific literature. The Agency has found that currently registered uses of dazomet
are eligible for reregistration provided the mitigation and labeling outlined in this RED are
implemented.
The document consists of five sections. Section I contains the regulatory framework for
reregistration. Section II provides a profile of the use and usage of the chemical. Section III
provides a general fumigant overview and also summarizes dazomet's risk assessments. Section
IV presents the Agency's reregistration eligibility and risk management decisions. Section V
summarizes label changes necessary to implement the risk mitigation measures outlined in
Section IV. Unless otherwise noted, all Agency references in this document are available for
review in the dazomet docket (EPA-HQ-OPP-2005-0128) at www.Regulations.gov.
II. Chemical Overview
A. Chemical Identity
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When dazomet is applied to soil, either to the surface or incorporated, it quickly breaks
down. The major degradate is MITC, but formaldehyde, monomethylamine, hydrogen sulfide
and (in acid soils) carbon disulfide, are also formed. All of these degradates are gases or volatile
liquids which diffuse through the spaces in the soil, killing living organisms with which they
come in contact. This reregi strati on eligibility decision considers risks of exposure of dazomet
and the major degradate, MITC, as a result of dazomet applications. Table 1 provides a
summary of the dazomet and MITC nomenclature.
Table 1: Dazomet and MITC Nomenclature
Properties
Chemical Structure
Chemical Group
Common Name
Molecular formula
Molecular Weight
CAS No.
PC Code
Case Number
Dazomet
rV
^N^^^S
Dithiocarbamate
Dazomet
C5H10N2S2
162.28
MITC
/N^
H3C 'C S
sothiocyanate
Methyl isothiocyanate
C2H3NS
73.12
533-74-4 556-61-6
035602 068103
2135 pSfot Applicable
B. Use and Usage Profile
Soil Uses
Pesticide Type:
Target pests:
Use patterns:
Formulations:
Methods of
Broad spectrum soil fumigant with herbicidal, nematicidal, and
fungicidal properties
Weeds, nematodes and various soil-borne pathogens
Golf greens/tees, nonbearing crops (such as orchard crops,
berries, and flower bulbs), turf sites (establishing or renovating),
ornamental sites (establishing or renovating), field nurseries
(establishing or renovating), compost piles, potting soils, and
strawberries and tomatoes in California only
Granular
Tractor drawn spreaders and handheld equipment such as belly
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Application:
grinders and push-type spreaders
Application Rates: Maximum application rate for incorporated applications is 530
Ibs ai/acre and for surface applications is 265 Ibs ai/acre
Technical
registrant:
Annual Usage:
Certis USA, LLC
Approximately 15,000 pounds of dazomet are used annually1 as
a soil fumigant.
Pesticide Type:
Target pests:
Use patterns:
Formulations:
Methods of
Application:
Application Rates:
Technical
registrant:
Antimicrobial Uses
Algaecide, bacteriostat, fungicide, microbiocide, mildewcide
Fungi, bacteria, mildew, algae
Dazomet may be used in a variety of ways including: 1) as a
treatment during the production of pulp and paper; 2) as a
material preservative treatment for coatings, adhesives, epoxy
flooring compounds, slurries, and high viscous suspensions; 3)
as a biocide treatment used during petroleum operations; 4) as a
biocide treatment to recirculating cooling water systems; and 5)
as a remedial wood treatment to utility poles.
Pelleted/tableted, liquid (soluble concentrate and flowable
concentrate) solutions, water soluble packaged solids, ready to
use solutions
Open pour (for both solid and liquid formulations), metering
pump, and water-soluble packaged solid mixing
Rates vary by application use site and method. Maximum rates
are included in Table 4.1 of the Revised Occupational and
Residential Antimicrobial Exposure Assessment (Walls, C.
2/14/08)
BASF
USDA Agricultural Chemical Usage 2003 Nursery and Floriculture Summary, September 2004,
http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID= 1001.
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C. Regulatory History
Dazomet, (PC code 035602) and the sodium salt, tetrahydro-3,5-dimethyl-2H-l,3,5-
thiadiazine-2-thione (PC Code 035607) are included in pesticide reregistration case number
2135. Currently, there are 23 products registered containing dazomet and there are no active
products registered containing the sodium salt.
Dazomet has both agricultural and antimicrobial uses. Dazomet was first registered in
the United States in 1967 as an algaecide, a bacteriostat, and a microbicide in a variety of
commercial and industrial applications such as pulp and paper mills, cooling tower waters, and
adhesives.
In the late 1980s pre-plant soil uses of dazomet were registered. Dazomet is registered
for use on non-bearing orchard crops, ornamentals, and turf to control plant pathogens,
nematodes, and weeds. Unlike other soil fumigants, dazomet is applied as a dry granule and
incorporated into the soil or applied to the soil surface and watered into the soil to activate it.
A Phase IV data call-in (DCI) was issued for dazomet in January 1991 and included data
requirements for ecotoxicity, toxicology, and environment fate. A follow-up DCI was issued in
May of 1992 that included data requirements for neurotoxicity and the nature of residue in
plants. Dazomet was also included in the October 1995 agricultural reentry data call-in.
III. Dazomet Risk Assessments
A. General Overview of Soil Fumigants
Soil fumigants are pesticides that form gasses when applied to soil. Once in the soil, the
fumigants work by controlling pests that can disrupt plant growth and crop production. Soil
fumigants play a very important role in agriculture, but they also have the potential to pose risk
concerns to people involved in application of the chemicals (handlers), workers who re-enter
fumigated fields (workers), and people who may be near the treated area (bystanders).
1. Human Health Risk
When dazomet is applied and mixes with moist soil, it is quickly broken down into
several products. One of these products is MITC that accounts for most of the fumigant activity.
The main risk of concern for handlers, workers, and bystanders associated with the soil uses of
dazomet is from acute inhalation exposure to MITC as a result of fumigant off-gassing.
Dazomet handlers also are at risk from direct fumigant exposure during applications. The term
handler refers to persons involved in the application of dazomet. For soil applications, handlers
also include persons involved in perforating and removing of tarps. The term worker in this
document refers to persons performing non-handler tasks within the application block, after the
fumigation process has been completed, such as planting. The term bystander refers to any
person who lives or works in the vicinity of a fumigation site.
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In addition to soil use, dazomet is also used as an antimicrobial pesticide in the following
ways: 1) as a treatment during the production of pulp and paper; 2) as a material preservative
treatment for coatings, adhesives, epoxy flooring compounds, slurries, and high viscous
suspensions; 3) as a biocide treatment used during petroleum operations; 4) as a biocide
treatment to recirculating cooling water systems; and 5) as a remedial wood treatment to utility
poles.
Estimating exposure to fumigants is different from non-fumigant pesticides due to
fumigants' volatility and ability to move off site during and after application. For example,
pesticide spray drift is the physical movement of pesticide particulate or droplets from the target
site during the application and soon thereafter. In the case of soil fumigants, the pesticide moves
as a gas (not as particulate or droplets) and movement off-site can occur for an extended period
after application. Importantly, fumigants have a well-documented history of causing large-scale
human exposure incidents up to several thousand feet from treated fields. Assessing fumigant
exposure takes into account the size of the fumigated field, the amount of fumigant applied, and
the rate at which the fumigant escapes from the treated field.
The term "flux rate" or "emission rate" defines the rate at which a fumigant off-gasses
from a treated field. Many factors influence the rate of emissions from treated fields. Factors
such as the application method, soil moisture, soil temperature, organic matter levels, water
treatments, the use of tarps, biological activity in the soil, soil texture, weather conditions, soil
compaction, and others influence the amount of fumigant that comes off the field and is available
to move off-site to areas where bystanders may be located.
The human health risk assessment indicates that acute inhalation exposures to MITC
concentration of 22 ppb or greater for a 1 to 8 hour time period for non-occupational (residential)
bystanders and occupational handlers could pose risks of concern. The 22 ppb concentration is
based on a reversible endpoint from a human eye irritation and odor threshold study for acute
exposures to MITC. The lowest observable adverse effect level (LOAEL) was 800 ppb, and the
human concentration (HC) based on the no observable adverse effect level (NOAEL) from this
study is 220 ppb. The NOAEL of 220 ppb being used by EPA is similar to a benchmark
concentration level of 200 ppb submitted by the group Toxicology Excellence in Risk
Assessment (TERA) on behalf of the metam sodium registrants. The benchmark concentration
analysis thus supports the Agency's toxicity endpoint. Since the study is a human exposure
study for acute eye exposures to MITC, the standard 10X for animal to human extrapolation is
not needed. A 10X uncertainty factor for intraspecies variability was included, which when
applied to the HC, results in the target concentration for acute inhalation exposures of 22 ppb.
California Pesticide Illness Surveillance Program data from 1992-2003 confirm that eye
effects from MITC exposure as seen in this human study provide a sensitive endpoint for
regulating acute inhalation exposures. In many incident cases, people complain of eye effects.
However, many reported cases also report systemic or respiratory effects, while some are effects
without eye irritation. Compared to eye irritation, the systemic and respiratory effects are more
adverse in nature. Unfortunately, the available toxicity data in animals or humans do not allow a
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quantitative comparison of the dose response curves of the eye, systemic, and respiratory effects
to determine at the exact doses those effects occur. However, the Agency believes eye irritation
provides a surrogate for other toxic effects and thus makes this the appropriate endpoint to
regulate. To ensure that this endpoint is protective of any effects from repeated and longer term
exposures, EPA is requiring data to evaluate developmental, reproductive, chronic, and cancer
hazards and has encouraged the registrants to purse additional studies to characterize the dose
response curves of different target organs.
In assessing risks from dazomet, the Agency considered multiple lines of evidence, using
the best available information from monitoring studies, modeling tools, and from incidents.
Monitoring: For the human health risk assessments completed for dazomet and the other
soil fumigants within the group, several field-scale monitoring studies were considered.
These studies quantify dazomet concentrations in and around fields at various times and
distances during and after applications. Many of these data indicate that there can be
risks of concern associated with dazomet use at a broad range of distances from treated
fields. However, these data are limited in their utility because they provide results only
for the specific conditions under which the study was conducted.
Modeling: Models enable the use of data from monitoring studies to estimate
concentrations and potential risks under a wide range of conditions and use patterns.
EPA used the Version 2.1.4 of the Probabilistic Exposure and Risk model for Fumigants
(also called the PERFUM model) to evaluate potential risks at distances around treated
fields. PERFUM incorporates actual weather data and flux distribution estimates, and
then accounts for changes and altering conditions. Analyses based on a variety of model
outputs were used to compare the potential risks at a range of distances. The PERFUM
model and users manual are public domain and can be downloaded at
Bystander, handler, and worker incident reports: Incidents for the soil fumigants
generally occur at a low frequency relative to the total number of fumigant applications
performed annually. However, when incidents occur, there are often many people
involved. Incidents involving handlers and workers tend to occur more often than
incidents with bystanders.
Reconstructing incidents to examine the exact factors which led to the incident can be
difficult, especially when bystanders are involved since all the factors that contributed to
the incident may not have been documented. Some of the factors that have been linked to
incidents in the past have included equipment failure, handler accidents, applicator failure
to adhere to label recommendations and/or requirements, and temperature inversions.
Bystander incidents have occurred both close to fumigated fields and up to two miles
away from the fumigated field, although these types of incidents have not been reported
specifically for dazomet.
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Based on these lines of evidence and as described in more detail in the risk assessments,
EPA has determined that dazomet risks to handlers, workers, and bystanders are of concern
given current labels and use practices. The human health risk assessments indicate that
inhalation exposures to bystanders who live and work near agricultural fields where dazomet
fumigations occur have the potential to exceed the Agency's LOG without additional mitigation
measures. There are also risks of concern for occupational handlers involved in dazomet
applications and for workers who may re-enter treated area shortly after fumigation or tarp
perforation has been completed.
For more information about the specific information in the Agency's human health risk analysis
for dazomet, refer to the documents listed below, all of which can be found in the dazomet
docket # EPA-HQ-OPP-2005-0128 at http://www.regulations.gov:
Dazomet: Updated Final Revised HED Chapter of the Reregistration Eligibility
Decision Document (RED). (Smith, C. et al., Dated June 2008)
Mode of Action, Eye Irritation, and the Intra-Species Factor: Comparison of
Chloropicrin andMITC. (Lowitt, A. and Reaves, E., Dated June 25, 2008)
2. Environmental Fate, Ecological Effects and Risks
The Agency's environmental fate and ecological effects risk assessments indicate that
there are some concerns for non-target organisms that may be exposed to fumigants. Exposure
to terrestrial organism such as birds and mammals could occur two ways, as either oral exposure
to dazomet granules or by the inhalation route of exposure to the breakdown product MITC.
Potential exposure to aquatic organisms may occur from surface runoff/leaching and/or
volatilization and deposition of MITC in water bodies.
Hazard
Dazomet is considered moderately toxic on an acute oral basis to both birds (LD50 = 424
mg/kg) and mammals (LD50 = 415 mg/kg). MITC is considered highly toxic on an acute oral
basis to mammals (LDso = 55 mg/kg), and moderately toxic via the inhalation route. Acute oral
and inhalation toxicity data with MITC are needed for birds.
MITC is considered very highly toxic to both fish (lowest LCso = 51.2 ppb) and aquatic
invertebrates (lowest LCso = 55 ppb).
Exposure
Terrestrial (Dazomet and MITC)
Direct exposure of mammals and birds to dazomet granules was estimated using the
model T-REX, Version 1.2.3 (T-REX, 2005). T-REX was run for tomato and strawberry crops
(also applicable to turf, ornamental and other pre-plant incorporated uses) for a single application
of dazomet applied at the maximum rate of 530 Ib a.i./A. In addition, exposure of terrestrial
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animals to the volatile degradation product MITC was evaluated using a preliminary LD50/square
foot risk screening method. The Industrial Source Complex Short Term (ISCST3) model
together with information about MITC emissions from a treated field was used to evaluate the
range of MITC concentrations which might be found under different conditions of application
rate, weather, source size and shape (e.g., field size in acres) and distance from the treated field.
Aquatic (MITC)
For exposure to fish and aquatic invertebrates, EPA considers surface water only, since
most aquatic organisms are not found in ground water. The aquatic exposure assessment for
MITC relied on Tier II aquatic models. The Pesticide Root Zone Model (PRZM version 3.1.2
beta) simulates fate and transport on the agricultural field, while the water body is simulated with
Exposure Analysis Modeling System (EXAMS version 2.98.04). Simulations are run for
multiple (usually 30) years and the reported EECs represent the values that are expected once
every ten years based on the thirty years of daily values generated during the simulation.
PRZM/EXAMS simulates a 10 hectare (ha) field immediately adjacent to a 1 ha pond, 2
meters deep with no outlet. The location of the field is specific to the crop being simulated using
site specific information on the soils, weather, cropping, and management factors associated with
the scenario. The crop/location scenario in a specific state is intended to represent a high-end
vulnerable site on which the crop is normally grown. Based on historical rainfall patterns, the
pond receives multiple runoff events during the years simulated. PRZM has limited capabilities
in capturing the amount of a volatile chemical in air, water and sediment. The estimated
concentrations of chemicals like MITC in surface water bodies may be upper bound.
To simulate field application of dazomet, multiple scenarios were selected representing
proposed dazomet usage areas based on geography and weather. PRZM and EXAMS models and
relevant scenarios were used to estimate MITC estimated exposure concentrations (EECs) in
surface water based on label information for dazomet application to tomatoes, strawberries, turf
and ornamental trees at the highest application rate. The scenario with the highest concentration
of MITC from dazomet applications was the California strawberry scenario.
Risk
Terrestrial Risk (Dazomet and MITC)
Available dazomet toxicity studies allow the assessment of acute oral exposure of birds
and mammals. Inhalation toxicity studies for MITC are only available for mammals. There are
currently no studies available to estimate chronic terrestrial risks.
The Agency's levels of concern are exceeded for acute oral consumption of dazomet
granular product for both mammal and bird species that are not Federally-listed as endangered or
threatened as well as for 'listed' species. However, for mammal inhalation exposure to MITC all
of the estimated risks are below the Agency's LOG for both listed and non-listed species. The
inhalation effects observed and assessed in mammals included both metaplasia of respiratory
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epithelium and lethality. There were no data available to assess inhalation risk to birds, and
additional data is required. At the present time there are no registrant-submitted toxicity studies,
or studies published in the open literature, that evaluates the toxicity of dazomet or MITC to
terrestrial plants.
Aquatic Risk (MITC)
None of the estimated acute fish or aquatic invertebrate risks were above the Agency's
LOG for freshwater non-listed or listed species. However, no MITC studies are available for
marine/estuarine organisms. For chronic risk from MITC the only data available to evaluate
chronic effects on aquatic organisms are for freshwater invertebrates, which predict risks below
the Agency's LOG. However, no MITC data are available to evaluate the chronic effects on
freshwater and estuarine/marine fish, or estuarine/marine invertebrates. All of the estimated
risks for aquatic plants were below the Agency's levels of concern.
Due to the current data gaps for dazomet and MITC, the Agency is requiring additional
eco-toxicity studies for both terrestrial and aquatic organisms. For more information on the
Agency's environmental fate and ecological effects risk analysis:
Revised Environmental Fate and Ecological Risk Assessment For Dazomet. (Khan. F.
and Felkel, 1, Dated April 8, 2008)
3. Benefits
Soil fumigation can provide benefits to both food consumers and growers. For
consumers it means more fresh fruits and vegetables can be cheaply produced year-round
because severe pest problems can be efficiently controlled. Growers benefit because crops
grown in fumigated soil produce fewer blemished products, which translates into an increase in
marketable yields. Fumigation can also provide benefits to growers by increasing crop
management flexibility. This includes shorter crop rotational intervals (i.e., less time when fields
are left fallow), improved ability to meet quarantine requirements (which are imposed when
states or other jurisdictions require a pest-free harvested product), and consistent efficacy against
critical pests. The magnitude of benefits depends on pest pressure, which varies over space and
time, and the availability and costs associated with the use of alternatives.
There are a number of benefits assessments that have been completed by the Agency to
estimate the value of these chemicals to various industries, which are listed below.
EPA-HQ-OPP-2005-0123-0321, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Metam-Sodium, and Methyl Bromide in Eggplant Production
EPA-HQ-OPP-2005-0123-0322, Assessment of the Benefits Soil Fumigants (Methyl
Bromide, Chloropicrin, Metam-Sodium, Dazomet) Used by Forest Tree Seedling
Nurseries
EPA-HQ-OPP-2005-0123-0323, Assessment of the Benefits of Soil Fumigation with
Methyl Bromide, Chloropicrin, Dazomet, Metam Potassium and Metam Sodium for Use
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in Raspberry Nurseries, Fruit and Nut Deciduous Tree Nurseries, and Rose Bush
Nurseries in California
EPA-HQ-OPP-2005-0123-0324, Assessment of the Benefits of Soil Fumigation with
Chloropicrin and Metam-sodium In Onion Production
EPA-HQ-OPP-2005-0123-0325, Assessment of the Benefits of Soil Fumigation with
Methyl Bromide, Chloropicrin and Metam-sodium In Grape Production
EPA-HQ-OPP-2005-0123-0326, Assessment of the Benefits of Soil Fumigation with
Methyl Bromide, Chloropicrin and Metam-sodium In Tree Nut Production
EPA-HQ-OPP-2005-0123-0327, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, and Methyl Bromide In Pome Fruit Production
EPA-HQ-OPP-2005-0123-0328, Assessment of the Benefits of Soil Fumigation with
Methyl Bromide, Chloropicrin, and Metam Sodium In Stone Fruit Production
EPA-HQ-OPP-2005-0123-0329, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, and Metam-Sodium in Bell Pepper Production
EPA-HQ-OPP-2005-0123-0330, Assessment of the Benefits of Soil Fumigation with
Metam-sodium in Potato Production
EPA-HQ-OPP-2005-0123-0331, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, and Metam-sodium In Strawberry Production
EPA-HQ-OPP-2005-0123-0332, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, Metam-sodium, and Dazomet In Strawberry Nursery
Runner Production
EPA-HQ-OPP-2005-0123-0333, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide and Metam-sodium In Sweet Potato Production
EPA-HQ-OPP-2005-0123-0334, Assessment of the Benefits of Soil Fumigation with
Chloropicrin In Tobacco Production
EPA-HQ-OPP-2005-0123-0335, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, and Metam-sodium in Tomato Production
EPA-HQ-OPP-2005-0123-0336, Assessment of the Benefits of Soil Fumigation with
Metam Sodium in Carrot Production
EPA-HQ-OPP-2005-0123-0337, Assessment of the Benefits of Soil Fumigation with
Metam Sodium in Peanut Production
EPA-HQ-OPP-2005-0123-0338, Assessment of the Benefits of Soil Fumigation with
Chloropicrin, Methyl Bromide, Metam Sodium and Dazomet in Ornamental Production
EPA-HQ-OPP-2005-0123-0339, Summary of the Benefits of Soil Fumigation with
Methyl Bromide in Crop Production
EPA-HQ-OPP-2005-0123-0340, BEAD'S Planned Impact Assessments on Agricultural
Sites with Significant Use of Soil Fumigants
B. Antimicrobial Risk
In addition to the use of fumigants to sterilize soil before planting, there are a number of
antimicrobial uses that the Agency has assessed in this RED. Dazomet may be used as an
antimicrobial chemical in the following ways: 1) as a treatment during the production of pulp
and paper; 2) as a material preservative treatment for coatings, adhesives, epoxy flooring
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compounds, slurries, and high viscous suspensions; 3) as a biocide treatment used during
petroleum operations; 4) as a biocide treatment to recirculating cooling water systems; and 5) as
a remedial wood treatment to utility poles.
All of the occupational handler risks were below the Agency's LOG except for some
scenarios with the following uses: preservation of epoxy flooring compounds, pulp and paper
slimicide use, and microbe control in large water cooling systems.
For more information on these antimicrobial uses:
Dazomet Antimicrobial Risk Mitigation Paper. (Garvie, H., Dated June 2008)
Dazomet: Revised Occupational and Residential Exposure Assessment of Antimicrobial
Uses for the Reregistration Eligibility Decision (RED) Document. (Walls, C., Dated June
2008)
Please refer to the RED Appendix for the complete document citations, which are also
available in the dazomet docket (OPP-2005-0128) at www.regulation.gov.
IV. Risk Management and Reregistration Decision
A. Determination of Reregistration Eligibility
Section 4(g)(2)(A) of FIFRA calls for the Agency to determine, after submission of
relevant data concerning an active ingredient, whether or not products containing the active
ingredient are eligible for reregi strati on. The Agency has previously identified and required the
submission of the generic (i.e., active ingredient-specific) data to support reregi strati on of
products containing dazomet. The Agency has completed its assessment of the residential,
occupational, and ecological risks associated with the use of pesticides containing the active
ingredient dazomet.
In Phase 5, the Agency published a risk mitigation options paper.2 This document detailed
potential mitigation options and sought public comment on these options. The following is the
list of mitigation options discussed in the Agency's paper:
Buffer zones;
Sealing methods;
Timing of applications;
Application block size limitations;
Respiratory protection;
Tarp perforation/removal procedures;
Entry-restricted period;
2 EPA-HQ-OPP-2005-0128-0031, Risk Mitigation Options to Address Bystander and Occupational Exposures from
Soil Fumigant Applications
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Application method/practice restrictions;
Fumigant management plans (FMPs);
FMP certification;
Responsible parties;
Record keeping/reporting/tracking;
Restricted Use Pesticide Classification;
Notification and posting;
Good agricultural practices;
Fumigant manuals; and
Stewardship programs.
Based on a review of the dazomet database and public comments on the Agency's
assessments for dazomet, the Agency has sufficient information on the human health and
ecological effects of dazomet to make decisions as part of the reregi strati on process under
FIFRA. The Agency has determined that dazomet products are eligible for reregi strati on
provided that (i) required product specific data are submitted, (ii) the risk mitigation measures
outlined in this document are adopted, and (iii) label amendments are made to implement these
mitigation measures, as outlined in Chapter V. Appendix A summarizes the uses of dazomet that
are eligible for reregi strati on.
The Agency's decision takes into account the best available information on the potential
risks and benefits of metam use. In reaching its reregi strati on decision and developing the
dazomet mitigation proposal, EPA considered a range of factors, including: characteristics of
bystander and other populations exposed to dazomet; hazard characteristics of dazomet and
MITC; available information on levels of exposure, feasibility, cost, and effectiveness of various
risk mitigation options; incident information; public comments; potential impacts of mitigation
on growers ability to produce crops; availability of efficacious alternatives; comparative risks of
alternative control methods; and the uncertainties and assumptions underlying the risk and
benefit assessments.
A substantial amount of research is currently underway or is expected to begin in the near
term to (1) address current data gaps, and (2) refine understanding of factors that affect fumigant
emissions. Additionally, a number of new methods and technologies for fumigation are
emerging. EPA plans to move the soil fumigants forward in Registration Review, from 2017 to
2013, which will allow EPA to consider new data and information relatively soon, determine
whether the mitigation included in this decision is effectively addressing the risks as EPA
believes it will, and to include other soil fumigants which are not part of the current review.
The Registration Review process for dazomet and the other soil fumigants will also
include a comprehensive endangered species assessment. Once that endangered species
assessment is completed, further changes to dazomet labels may be necessary.
B. Public Comments and Responses
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The Phase 3 public comment period on the preliminary risk assessments and related
documents for dazomet lasted from July 13 through October 12, 2005. EPA-HQ-OPP-2005-
0128-0062 contains the Agency responses to Phase 3 public comments related to dazomet uses.
EPA revised its risk assessments and developed benefits and risk mitigation options during
Phase 4. The Phase 5 public comment period on revised risk assessments, benefits analysis, and
risk management options took place from May 2 to November 3, 2007. Comments on issues
which were significant to many stakeholders and directly influenced EPA's decisions are
highlighted in this document as well as EPA's responses to those comments. The following
documents include EPA's responses to comments related to dazomet which may be found in the
dazomet docket.
The Health Effects Division's Response to Comments on EPA 's Phase 5
Reregistration Eligibility Decision Document for Dazomet. (Smith, C., Dated June
2008)
Response to Phase 5 Public Comments on the Phase 4 Dazomet Environmental
Fate and Ecological Risk Assessment. (Khan, F., and Felkel, J., Dated April 2,
2008)
Response to Phase 5 BEAD Related Public Comments Received on the
Reregistration of Chloropicrin, Dazomet, Metam Potassium, Metam Sodium, and
Methyl Bromide. (Donaldson, D. et al., Dated June 2008)
Review of Stakeholder Submitted Impact Assessments of Proposed Fumigant
Buffers, Comments on Initial Buffer Zone Proposal, and Case Studies of the Impact
of a Flexible Buffer System for Managing By-Stander Risks ofFumigants. (Wyatt,
T., et al, Dated June 2008)
Phase 6 Response to Substantive Public Comments on Antimicrobials Division's
Occupational and Residential Assessments for the Reregistration Eligibility
Decision (RED) Documents for the following chemicals: Methylisothiocyanate
(M1TC), Metam Sodium, Dazomet, and Chloropicrin. (Walls, C., Dated February
14, 2008)
SRRD 's Response to Phase 5 Public Comments for the Soil Fumigants. (Dated July
2008)
C. Regulatory Position
1. Regulatory Rationale
The Agency has determined that dazomet is eligible for reregi strati on provided the risk
mitigation measures outlined in this document are adopted and label amendments are made to
reflect these measures. The following is a summary of the rationale for managing risks
associated with the use of dazomet. Where labeling revisions are warranted, specific language is
set forth in the summary table in Section V of this document.
a. Dazomet Soil Uses
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i. Rate Reduction and Use Sites
Rate
The current maximum application rates for dazomet are 530 Ibs ai/A for incorporated
applications and 265 Ibs ai/A for surface applications. According to the dazomet soil use
registrant, Certis, USA LLC, the actual use rate of dazomet is usually much lower for most uses
of dazomet. The turf and ornamental use rarely requires the maximum rate, except for golf
course or turf renovation. For crop uses, the rate generally ranges from 200-300 Ibs ai/A,
although there are some cases where an application up to 400 Ibs ai/A is needed. Therefore, the
registrant has agreed to lower the maximum use rate of dazomet to 425 Ibs ai/A for all registered
uses except for golf course/turf renovation. The maximum rate for golf course/turf renovation
will remain at 530 Ibs ai/A.
Use Sites
Dazomet is not used in greenhouses; however current labels include some instructions for
use in greenhouses on labels. The registrant has confirmed that dazomet is not supported for use
in greenhouses, and all labels will be amended to delete references to use in greenhouses and add
a statement prohibiting use in greenhouses. See Table 4, the label table for additional
information.
ii. Human Health Risk Management
For details on the dazomet human health risk assessment for soil uses, please refer to the
Human Health Risk Assessments referenced in Section III of this document. These documents
are also available in the public docket EPA-HQ-OPP-2005-00128, located on-line in the Federal
Docket Management System (FDMS) at http://www.regulations.gov.
Dietary Risk
Based on the currently registered use patterns for dazomet, dietary exposure, including
exposure from drinking water, is not expected and no dietary risk mitigation is warranted for
dazomet at this time.
Bystanders, Workers, and Handlers
The human health risk assessments indicate that inhalation exposure to bystanders who
live and work near agricultural fields, nurseries, golf courses, and other areas where dazomet
fumigations occur, and to handlers involved in the application of dazomet have the potential to
exceed the Agency's LOG without additional mitigation measures.
To reduce the potential for exposure to bystanders, handlers, and workers and to address
subsequent risks of concern, EPA is requiring a number of mitigation measures which include:
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Reducing maximum application rates;
Clarifying use sites;
Buffer zones;
Dermal protection for handlers;
Respiratory protection and air monitoring for handlers;
Restrictions on the timing of perforation and removing of tarps;
Posting;
Good agricultural practices;
Fumigant management plans;
Emergency preparedness and response plans; and
Notice to state lead agencies.
The Agency also believes that registrant developed training and community outreach and
education programs, which are also implemented by the registrant, will help reduce risk.
Additionally, EPA is interested in working with registrants to identify additional measures that
could be implemented as part of product stewardship. These additional measures should include
efforts to assist users' transition to the new label requirements.
Some of the required mitigation measures only address one group of potentially exposed
individuals (i.e., bystanders, handlers, or workers), while other measures will help reduce risk to
more than one group. All mitigation measures are designed to work together to reduce
exposures, enhance safety, and facilitate compliance and enforcement. The Agency has based its
risk mitigation decision on a flexible approach which EPA believes will be protective and allow
users to make site-specific choices to reduce potential impacts on benefits of the use. While
some of these measures, buffer zones for example, can be used to estimate MOEs, others such as
emergency preparedness and response and community education will contribute to bystander
safety, but are difficult to express in terms of changes to quantitative risk estimates such as
MOEs. However, EPA has determined that these measures, working together, will prevent
unreasonable adverse effects on human health.
aa. Bystander Risk Mitigation
Bystanders are persons who live and/or work near fumigated fields and are potentially
exposed to fumigant emissions that travel off-site. In some cases the bystanders are workers
performing agricultural tasks in nearby fields. If they are employed by the grower who has
control of the fumigated field, they are more likely to be aware that a fumigant application has
occurred.
Bystander risks for people that live near treated fields differ from other human health
risks evaluated under FIFRA, for example residential and worker reentry risks. Unlike
residential exposures resulting from use of products to control pests in and around the home,
non-occupational bystanders receive no direct benefit from the pesticide which was applied
elsewhere. These bystanders have not made a decision to purchase a pest control product or
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service, and as a result they have little access to information about the product (e.g., hazards,
safety information, first aid, etc.) or symptoms of exposure. Additionally, non-occupational
bystander exposures to fumigants are largely involuntary and unanticipated. In this regard non-
occupational bystander exposure is similar to dietary exposure in that people consuming foods or
drinking water expect to be safe from possible adverse effects associated with pesticide residues
that could be present in their food and drinking water.
Unlike workers, non-occupational bystanders typically receive no safety information or
training related to the pesticide to which they may be exposed. Whereas workers are generally
expected to play an active role in protecting themselves from pesticide risk, no such expectation
exists for non-occupational bystanders. Workers who experience symptoms of pesticide
exposure are also more likely to link their symptoms to the pesticide and take steps to receive
appropriate treatment. Conversely, bystanders are much less likely to attribute adverse effects to
pesticide exposures or to have access to information needed to take appropriate steps to mitigate
the effects of the exposure. Thus, EPA's mitigation includes elements for emergency
preparedness and response, notice to state lead agencies, training, and community outreach and
education as well as labeling changes.
1. Buffer Zones
The human health risk assessment indicates bystanders may be exposed to MITC air
concentrations from applications of dazomet that exceed the Agency's LOG. In general, the risk
from inhalation exposures decreases as the distance from the field to where bystanders are
located increases. Because of this relationship, the Agency is requiring that a buffer zone be
established around the perimeter of each application block where dazomet is applied. The
Agency acknowledges that buffer zones alone will not mitigate all inhalation risks and eliminate
incidents caused by equipment failure, human error, and weather or other events (e.g.,
temperature inversions). The Agency however does believe that buffer zones along with other
mitigation measures required by this decision described below will mitigate risks so that
bystanders will not experience unreasonable adverse effects.
The Agency considered various buffer zone schemes ranging from fixed buffer zones for
every application to site-specific buffer zones. During the most recent comment period, the
Agency received input in favor of a flexible buffer approach that would allow fumigant users to
determine the buffer zone distance based on site conditions and application practices. While the
Agency believes that site-specific buffer zones would provide the most flexibility for users, the
EPA currently does not have sufficient data to support this scheme. As a result, the Agency has
developed a scalable buffer zone system that does provide flexibility by setting buffer zones for
different application methods at various acreages and application rates.
Version 2.1.4 of the Probabilistic Exposure and Risk model for Fumigants (also called
the PERFUM model) combined with monitoring data and incident data were used to characterize
the risk for specific buffer zone distances corresponding to the range of application scenarios
anticipated. Additional information on the PERFUM inputs and outputs can be found in Agency
risk assessment, (EPA-HQ-OPP-2005-0123-0285), in a June 2006 a peer-reviewed article
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describing the model (httji;//wwwjo^^^ and/or the
PERFUM user's guide which can be download from the internet
(http://www.exponent.com/perfum/). A CD containing all of the PERFUM input/output files and
files with the PERFUM MOE/air concentration analysis that were considered for this decision
are available upon request at the OPP Docket Office.
General Buffer Zone Requirements
The following describes the general buffer zone requirements for dazomet and other soil
fumigants currently going through the reregi strati on process:
"Buffer zone" is an area established around the perimeter of each application block where a
soil fumigant is applied. The buffer zone must extend from the edge of the application block
perimeter equally in all directions.
All non-handlers including field workers, nearby residents, pedestrians, and other bystanders,
must be excluded from the buffer zone during the buffer zone period except for transit (see
exemptions section).
An "application block" is a field or portion of a field treated with a fumigant in any 24-hour
period (see Figures 1 and 2 below for further explanation).
The "buffer zone period" starts at the moment when any fumigant is delivered or dispensed
to the soil within the application block and lasts for a minimum of 48 hours after the
fumigant has stopped being delivered/dispensed to the soil.
Buffer zone distances
Buffer zone distances must be based on look-up tables on product labels (25 feet is the
smallest distance regardless of site-specific application parameters).
Authorized entry to buffer zones
Only authorized handlers who have been properly trained and equipped according to EPA's
Worker Protection Standard (WPS) and label requirements may be in the buffer zone during
the buffer zone period.
Buffer zone proximity
To reduce the potential for off-site movement from multiple fumigated fields, buffer zones
from multiple MITC generating application blocks may not overlap (including blocks
fumigated by adjacent property owners, see below for exemptions for areas not under the
control of owner/operator of application block).
No fumigant applications will be permitted within 0.25 miles of schools, state licensed day
care centers, nursing homes, assisted living facilities, elder care facilities, hospitals, in-patient
clinics and prisons if occupied during the buffer zone period.
Exemptions for transit through buffer zones
Vehicular and bicycle traffic on public and private roadways through the buffer zone is
permitted. "Roadway" means that portion of a street or highway improved, designed or
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ordinarily used for vehicular travel, exclusive of the sidewalk or shoulder even though such
sidewalk or shoulder is used by persons riding bicycles. In the event a highway includes two
or more separated roadways, the term "roadway" shall refer to any such roadway separately.
(This definition is based on the definition of roadway in the Uniform Vehicle Code prepared
by the National Committee on Uniform Traffic Laws and Ordinances. See
http://www.ncutlo.org/ for more details)
Bus stops or other locations where persons wait for public transit are not permitted within the
buffer zone.
See posting section for additional requirements that may apply.
Structures under the control of owner/operator of the application block
Buffer zones may not include buildings used for storage such as sheds, barns, garages, etc.,
UNLESS,
1. The storage buildings are not occupied during the buffer zone period, and
2. The storage buildings do not share a common wall with an occupied structure.
See posting section for additional requirements that may apply.
Areas not under the control of owner/operator of the application block
Buffer zones may not include residential areas (including yards), employee housing, private
property, buildings, commercial, industrial, and other areas that people may occupy
UNLESS,
1. The occupants provide written agreement that they will voluntarily vacate the buffer zone
during the entire buffer zone period, and
2. Reentry by occupants and other non-handlers does not occur until air monitoring after the
buffer zone periods end indicates that the air concentrations within the structure/space is
less than the acceptable air concentration on the label, as determined by air monitoring
requirements described on product labels.
Buffer zones may not include agricultural areas owned/operated by persons other than the
owner/operator of the application block, UNLESS
1. The owner/operator of the application block can ensure that the buffer zone will not
overlap with a buffer zone from any adjacent property owners, and
2. The owner/operator of the areas that are not under the control of the application provides
written agreement to the applicator that they, their employees, and other persons will stay
out of the buffer zone during the entire buffer zone period.
Buffer zones may not include publicly owned and/or operated areas (e.g., parks, rights of
way, side walks, walking paths, playgrounds, athletic fields, etc), UNLESS,
1. The area is not occupied during the buffer zone period,
2. Entry by non-handlers is prohibited during the buffer zone period, and
3. Written permission to include the public area in the buffer zone is granted by the
appropriate state and/or local authorities responsible for management and operation of the
area.
See posting section for additional requirements that apply.
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PERFUM Model Inputs
The major input parameters for the modeling were: application rates, application block
sizes, application method emission profiles, weather conditions, and the target air concentration
(based on acute inhalation endpoint and uncertainty factors). The following summarizes the key
points for each of these input parameters.
Rates
The maximum rates for soil applications of dazomet are 530 Ibs ai/A for incorporated
applications and 265 Ibs ai/A for surface applications. Since there is limited use information on
typical dazomet rates, a range of rates was modeled. The rates used in the model included the
maximum, along with rates at 75%, 50%, and 25% of the maximum for both surface and
incorporated applications.
Rates for bedded or strip applications (Ib ai per treated area) were converted to broadcast
equivalent application rate to determine the minimum buffer zone distance. In Figures 1 and 2
(shown below), the dashed line represents the perimeter of the field, the shaded area is the
portion of the field that is treated, and the un-shaded area is the untreated portion of the field.
Assuming both fields are 10 acres, and only 50% of field in Figure 2 is fumigated, the rate per
treated acre is 400 Ibs ai/A for both Figure 1 and 2. The broadcast rate for Figure 1 is 400 Ib
ai/A but the effective broadcast equivalent rate for Figure 2 is 200 Ibs ai/A. Labels may express
rates as Ibs per treated acre under the application instructions but they must identify buffer zone
distances based on the broadcast or effective broadcast equivalent rates.
Figure 1. Broadcast Application Figure 2. Bedded Application
Block Sizes
The Agency has limited information available on the size of application blocks treated in
a given day but according to the registrants, dazomet is generally applied to a smaller number of
acres than other fumigants, typically from 5 to 20 acres. The modeling did consider block sizes
up to 40 acres per day for dazomet, and so based on the registrant comment the application block
size will be limited to 40 acres for dazomet.
The application block size pertains to size of the field and not the size of the area treated.
The area inside the dashed lines in both Figures 1 and 2 is the application block. In this example
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the application block size for both figures is 10 acres. For both figures, 10 acres would be used
to determine the buffer zone distance.
Emission Studies
The Agency's Phase 5 risk assessment includes modeling of the two main ways that
dazomet is applied, surface or soil-incorporated. Details of these emission studies can be found
in Appendix D of the Dazomet: Final Revised HED Chapter of the Reregistration Eligibility
Decision Document (RED).
Weather
It is estimated that the major use of dazomet is in California and Washington. Some use
in Michigan and Florida (or elsewhere in those regions) is also estimated. As a result, weather
data for the following locations were included in this assessment: Bakersfield, CA; Ventura, CA;
Flint, MI; Tallahassee, FL; Bradenton, FL; and Yakima, WA. Each modeling run used five years
of weather (i.e., 1,825 potential application days) for each weather data set. Generally, Ventura,
and Bradenton weather data result in the largest buffer zone distances, Bakersfield, Tallahassee,
and Yakima data fall in the middle, and Flint data resulted in the smallest buffers.
Target Air Concentration
As described in the Human Health Risks section of Chapter III, the 22 ppb target air
concentration is based on a reversible sensitive endpoint from a human eye irritation and odor
threshold study for acute exposures to MITC, with a 10X uncertainty factor for intraspecies
extrapolation. The lowest observable adverse effect level (LOAEL) was 800 ppb and the human
concentration (HC) based on the no observable adverse effect level (NOAEL) from this study is
220 ppb.
PERFUM Model Outputs
The PERFUM model outputs are presented in percentiles for "whole field" and the
"maximum distance" distributions. The model also provides outputs as distributions of air
concentrations from which MOEs can be estimated. The following summarizes the key points
for each of these output parameters.
The maximum distance distribution is a compilation of the farthest predicted buffer
distances (i.e., the farthest downwind points) over 5 years of weather. The whole field
distribution differs because it includes all points around the perimeter for the same period.
Another way to consider the difference between the distributions is that maximum distance
results are a subset of the whole field results and that maximum distances allow for more
resolution at the upper percentiles of this distribution. Version 2.1.4 of PERFUM also allows for
direct consideration of air concentrations at various distances around treated fields. These air
concentrations and MOEs were also considered in the decision making process.
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An analysis based on a variety of PERFUM outputs was used in the buffer distance
determinations. This involved consideration of not only the typical maximum and whole-field
results, which are predictions of the distances at which a target concentration of concern (i.e., the
human concentration adjusted by applicable uncertainty factors) is achieved at varying
percentiles of exposure. In addition, a complementary approach, which determined the
percentiles of exposure for maximum and whole-field buffers at predetermined buffer distances,
was employed. Air concentration data were also used to calculate risk estimates (i.e., MOEs) at
predefined buffer distances and varied percentiles of exposure.
This overall approach allowed the Agency to utilize more of the information available
from PERFUM so that a more comprehensive view of the risks could be considered. Buffer
distances indicated by this type of analysis along with information from monitoring studies and
incidents were valuable in determining buffer distances to manage potential risks from dazomet
use when coupled with other mitigation measures.
Buffer Zone Distances
The Agency has developed buffer zones distances based on application rate and
application block size (rounding up to nearest rate and block size). These distances are
summarized in Table 2.
For each of the soil emission studies, distances were first chosen for the rates identified in
the risk assessment as the 100%, 75%, 50%, and 25% of the maximum rates for each application
method, as shown by the bolded red font in the table. For example, for surface applications the
rates were 265 Ibs ai/A, 200 Ibs ai/A, 132 Ibs ai/A, and 66 Ibs ai/A; and for incorporated
applications the rates were 530 Ibs ai/A, 400 Ibs ai/A, 265 Ibs ai/A, and 132 Ibs ai/A, with
application block sizes of 5, 20, and 40 acres. Distances for the other rates in the buffer zone
tables were scaled by assuming a linear relationship between the 100%, 75%, 50%, and 25%,
and maximum rates (e.g., distance at 37.5% rate = [distance at 25% rate + distance at 50%
rate]/2 ) with some adjustments for whole numbers. This scaling was necessary to provide an
incremental spread of rates. It should be noted that the distances in the lookup tables are not
model outputs, although the model outputs were used for their development.
Minimum and Maximum Buffer Zone Distances
For dazomet, the largest buffer distance is 1,080 feet for applications at a rate of 530 Ibs
ai/A and a 40 acre block size. Applications to larger block sizes and higher rates will be
prohibited for dazomet, based on comments from the registrants that dazomet users do not apply
to large areas at the very highest rates on current labels. A minimum buffer zone of 25 feet will
be required regardless of site-specific application parameters. In some instances the PERFUM
model predicts that the risks reach the target at the edge of the field, but the Agency believes that
a 25 foot minimum buffer is a good agricultural practice. While modeling may support no buffer
in some cases, a minimum buffer is being required because of variability in emission rate over a
field and other factors not accounted for in the modeling.
29
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Table 2: Buffer zone distances (in feet) for all dazomet soil applications
Block
Size
(acres)
1 or less
2
5
10
15
20
30
40
Block
Size
(acres)
1 or less
2
5
10
15
20
30
40
Application Rates for either surface or incorporated applications (Ibs ai/acre)
530
200
200
200
350
500
650
812
1080
400
75
100
150
239
329
440
599
770
390
72
96
147
233
318
426
582
750
380
69
92
144
226
308
412
565
730
370
66
88
141
219
298
398
548
710
360
63
84
138
213
287
384
531
690
350
60
80
135
207
278
370
514
670
340
57
76
132
201
269
356
496
650
330
54
72
128
194
259
343
480
630
320
51
68
124
187
250
330
460
610
310
48
64
120
179
237
317
446
590
300
45
60
116
172
227
305
430
565
290
42
56
112
164
216
288
411
545
280
39
52
108
158
208
275
400
524
270
36
48
104
156
208
260
383
505
265
33
44
100
152
204
250
369
500
260
30
40
89
141
193
245
360
490
250
25
36
78
130
182
234
345
471
240
25
32
67
119
170
223
330
452
Application Rates for either surface or incorporated applications (Ibs ai/acre)
230
25
28
56
108
160
212
323
433
220
25
25
46
98
149
201
308
414
210
25
25
36
87
139
190
293
395
200
25
25
25
79
133
187
281
375
190
25
25
25
76
128
179
268
357
180
25
25
25
74
122
171
255
339
170
25
25
25
71
117
163
242
321
160
25
25
25
68
111
154
229
303
150
25
25
25
65
105
145
215
285
140
25
25
25
62
99
136
202
267
132
25
25
25
58
92
125
188
250
130
25
25
25
58
92
125
188
250
120
25
25
25
53
82
110
164
218
110
25
25
25
48
72
95
141
186
100
25
25
25
43
62
80
117
154
90
25
25
25
38
52
65
94
122
80
25
25
25
33
42
50
70
90
70
25
25
25
28
32
35
47
58
66
25
25
25
25
25
25
25
25
30
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The buffer zone distances were not based on the selection of a specific percentile or
distribution from the PERFUM modeling results. Rather, EPA used a weight of evidence
approach to set the buffers which included consideration of the hazard profile of MITC,
information from incident reports, monitoring data, stakeholder comments along with
comprehensive analysis of results from PERFUM modeling and consideration of results using
other models (e.g., the Fumigant Emissions Modeling System or FEMS). Each model was
reviewed by the FIFRA Scientific Advisory Panel (SAP) in 2004 during the August and
September meetings (http://www.epa.gov/oscpmont/sap/nieetings/2004/index.htm). The
analysis of PERFUM results considered distances at various percentiles of the whole field and
maximum distance distributions, and predicted MOEs for various distances. The risk assessment
characterizes additional types of analysis that were performed. EPA's goal for risk management
was to achieve buffer distances where associated risks were at or above target concentration
levels at high percentiles of exposure. The following characterizes the risks associated with the
buffer zone distances summarized in Table 3:
This table shows the various buffer distances for each rate and block size. It also shows
the percentile for the whole and maximum distribution for each distance, as well as the
MOE at the 95th percentile air concentration of PERFUM2.
The target MOE for dazomet is 10, and the MOEs at these distances range from about 7
up to 30. Although the target air concentration is not below our LOG at all the distances,
at the lowest MOE of 7, the predicted air concentration would be 28 times lower than the
lowest observable adverse effect level (LOAEL) that is the level where the eye irritation
effects were first observed in the human study.
All of the whole field percentiles are above 90 percent, and the max percentiles range
from 37 to 99 percent.
As a result of the two flux studies the registrant submitted there is little apparent
difference in risk between the two methods when similar rates are compared. A greater
change in risk appears to come from altering the rate. Therefore, the buffer tables for
dazomet do not distinguish between the two methods of application; the tables are broken
down by rate and block size.
The use of GAPs, FMPs, and other mitigation measures required by this decision will
contribute to an additional decrease in risk (see GAP and FMP sections below on pages
50 and 51 respectively).
Example
Table 3 shows the required buffer zone distances and corresponding PERFUM modeling
results for the soil uses of dazomet using both the maximum distribution and the whole field
distribution to the target concentration based on an MOE of 10, as well as the MOE from the air
concentration outputs from PERFUM at the 95th percentile. The weather data selected here are
from Ventura, CA, since only California has agricultural uses registered which typically involve
larger application blocks than dazomet's other soil uses.
Focusing on the incorporated application method in the top row, using a 265 Ibs ai/A rate
on a 40 Acre block size, the buffer zone required for that application is 500 feet. The blocks
referenced in this example are shaded in gray in Table 3.
31
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At this distance using the PERFUM model to predict both the whole field and maximum
distributions the results indicate 91st percentile for whole field and 57th percentile for
maximum, as shown in the next two columns in the table.
o The risk level corresponding to this buffer zone distance at the 91st percentile
whole field distribution is equivalent to saying a person at any location on the
perimeter of the buffer zone during the 24 hour period following the fumigation
of a specific field during a 5-year period would have at least a 91 percent chance
of having of an exposure below the LOG (i.e., MOE of ^10).
o The risk level corresponding to the buffer zone distances at the 57th percentile
maximum distribution is equivalent to saying a person at the location on the
perimeter of the buffer zone where the maximum concentration occurs during the
worst case 24 hour period following the fumigation of a specific field during a 5-
year period would have a 57 percent chance of having of an exposure below the
LOG (i.e., MOE of ^ 10) for these typical use scenarios.
Using the PERFUM 2 model outputs of air concentrations to predict MOEs at the 95th
percentile, at 500 feet for these application parameters, the MOE is about 9 which is not
significantly below the target MOE of 10.
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Table 3: Dazomet's Buffers and Risk Estimates
Incorporated applications
Block
Size
(acres)
40
20
5
530lbsai/A(100%)
Max incorporated rate
Buffer
Distance
(feet)
1080
650
200
Percentile
using
PERFUMat
MOEof 10
Whole
93
93
92
Max
46
43
44
MOEat
95th
percentile
of
PERFUM2
7
7
7
400 Ibs ai/A (75%)
Buffer
Distance
(feet)
770
440
150
Percentile
using
PERFUMat
MOEof 10
Whole
93
93
92
Max
50
49
74
MOEat
95th
percentile of
PERFUM2
7
7
8
265 Ibs ai/A (50%)
Buffer
Distance
(feet)
250
100
Percentile
using
PERFUMat
MOEoflO
Whole
91
96
Max
53
63
MOEat
95th
percentile
of
PERFUM2
8
11
132 Ibs ai/A (25%)
Buffer
Distance
(feet)
250
125
25
Percentile
using
PERFUMat
MOEoflO
Whole
96
98
99
Max
72
73
98
MOEat
95th
percentile
of
PERFUM2
11
12
19
Surface applications
Block
Size
(acres)
40
20
5
265lbsai/A(100%)
Max surface rate
Buffer
Distance
(feet)
500
250
100
Percentile
using
PERFUMat
MOEof 10
Whole
92
91
93
Max
43
37
50
MOEat
95th
percentile
of
PERFUM2
8
7
9
200 Ibs ai/A (75%)
Buffer
Distance
(feet)
375
187
25
Percentile
using
PERFUMat
MOEoflO
Whole
91
92
93
Max
52
52
63
MOEat
95th
percentile of
PERFUM2
8
9
10
132 Ibs ai/A (50%)
Buffer
Distance
(feet)
250
125
25
Percentile
using
PERFUMat
MOEoflO
Whole
96
96
99
Max
71
72
91
MOEat
95th
percentile
of
PERFUM2
11
11
15
66 Ibs ai/A (25%)
Buffer
Distance
(feet)
25
25
25
Percentile
using
PERFUMat
MOEoflO
Whole
99
99
99
Max
98
98
99
MOEat
95th
percentile
of
PERFUM2
15
18
30
Ventura Weather Data is used to calculate all the numbers in this table since it was one of the worst weather scenarios and for the agricultural uses of dazomet
there is more use in California than Florida.
Shaded areas represent the numbers explained in the example above.
All values are approximate.
33
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The Agency believes that the buffer zone distances described above, combined with other
risk mitigation described herein, will provide protection against unreasonable adverse effects.
Buffer Zone Reduction Credits
The Agency has undertaken a significant effort to evaluate available empirical data,
modeling, and literature regarding the factors and control methods that may reduce emissions
from soil fumigants. For details on the Agency's analysis please see the June 9, 2008 memo
"Factors Which Impact Soil Fumigant Emissions - Evaluation for Use in Soil Fumigant Buffer
Zone Credit Factor Approach,"3 in the dazomet docket. The Agency has also coordinated and
led forums to discuss this issue at the 2006 and 2007 Methyl Bromide Alternatives Outreach
(MBAO) Conferences with leading researchers and other stakeholders. A general description of
the MBAO sessions can be found at http://mbao.org.
Based on the Agency's analysis of the current data, the Agency has developed dazomet
buffer zone reduction credits for: soils with high organic matter, and for soils with high clay
content. The Agency believes that in addition to reducing bystander risk and the size of buffer
zones, these credits have the potential to also decrease application rates. Applicators will be
required to document any information about buffer zone credits that apply in the Fumigant
Management Plan (FMP).
Soil Conditions
Soil conditions like the amount of organic matter and type of soil do have an impact on
fumigant emissions. However, soil conditions differ from other credits because they are
essentially beyond a grower's ability to change. Although a grower may not be able to
manipulate organic matter or soil type, the Agency's factors document indicates that soil
conditions can reduce fumigant emissions, and is offering credits for these conditions. EPA
acknowledges that some variability in soil characteristics within a given field is likely. If users
are unsure whether the fields they intend to treat meet the criteria for a credit, they may consult
with their local agriculture extension office or soil conservation district for assistance in
determining soil characteristics.
The Agency's factors document not only reviews available literature regarding soil
conditions, but also describes modeling exercises that estimate the impact of organic matter and
soil type using Chain_2D. Chain_2D is a first principles model that takes into consideration
factors such as boundary layers or moisture that could impact fumigant emissions. The Agency
used Chain_2D as modified by Dow AgroSciences' Steve Cryer and Ian van Wesenbeek in the
sensitivity analysis4 Cryer and van Wesenbeek modified the original source code to create a
more usable graphical user interface; this included incorporating a new air/soil boundary
3 Factors Which Impact Soil Fumigant Emissions - Evaluation for Use in Soil Fumigant Buffer Zone Credit Factor
Approach, June 9, 2008, DP Barcode: 306857.
4 Cryer, S.A. (2007) Air/Soil Boundary Conditions For Coupling Soil Physics and Air Dispersion Modeling.
Unpublished report of Dow AgroSciences LLC (Report # DN241493)
34
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condition proposed by Wang in 19985. See the Agency's factors analysis for further details
about the CHAIN_2D model6.
Based on the review of available literature and modeling with the CHAIN_2D model,
EPA believes 10 percent buffer zone credits are appropriate if the application block contains soil
with organic matter of greater than 3 percent and/or for clay content of at least 27 percent.
The Agency's Chain-2D sensitivity analysis suggests that organic matter can have a small
impact on emissions. There is generally a high correlation between the organic matter content of
the soils and the dissociation constant (Kd) value. Increasing Kd value by 10 or 25 percent
generally reduced emissions by 10 or 20 percent. Decreasing the Kd value by 10 or 25 percent
increased emissions by 10 or 20 percent (see figures 147 to 154 of the factors analysis for further
details).
Generally, clay loam and sandy clay loam soils tended to show significantly lower
emissions than other soil types, sometimes showing 50 percent lower reductions. Conversely,
loamy sand and loam soils tended to show higher emissions than other soil types (see figures 167
to 174 of the factors analysis for further details).
Dazomet buffer zone credits are additive and can not exceed 20 percent in total (e.g., 20
percent credit would apply for using > 3 percent organic content and >27 percent clay content).
For example, if an application block is 10 acres and the applicator is planning to apply
230 Ibs of dazomet per acre, the buffer distance from the look up tables is 108 feet. If after the
applicator tests the soil and determines the soil contains greater than 27 percent clay content,
then the buffer zone may be reduced by 10 percent. By calculating 10 percent of 108 feet (108
feet x 10% =10.8 feet buffer credit) and then subtracting the original buffer distance by the
credit (108 feet - 10.8 feet = about 97 feet) the final buffer distance required is 97 feet.
Other Buffer Zone Credits Considered
Currently the dazomet label allows for use of tarps when making applications, but there is
little information to suggest that growers are currently using tarps with dazomet. Since there is
no information available about how dazomet reacts with tarps, and since other data for metam
sodium suggests that standard tarps may not be very effective in trapping MITC vapors, there is
no tarp credit for dazomet at this time. If additional tarps or other emission factor data become
available to show the emissions from dazomet applications are decreased, the Agency will
consider adding those to the dazomet label. More information on the type of data the Agency is
looking for can be found in the Health Effects Division Recommendations for Fumigant Data
Requirements (J. Dawson, C. Smith, dated June 2008).
5 Wang, D; Yates, S.R.; Jury, W.A. (1998) Temperature Effect on Methyl Bromide Volatilization: Permeability of
Plastic Cover Films. J. Environ. Qual. 27, 821-827.
6 Factors Which Impact Soil Fumigant Emissions - Evaluation for Use in Soil Fumigant Buffer Zone Credit Factor
Approach, June 9, 2008, DP Barcode: 306857
35
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EPA (through OPP's Environmental Stewardship Branch) has proposed to co-fund a
grant with USDA-ARS for several flux studies in the southeastern U.S. These studies would
provide (1) field data on the emission reduction potential of certain low permeability barrier
films to support possible, additional, buffer reduction credits as well as to (2) help develop an
affordable and reliable hybrid field/lab test to evaluate the many barrier films available to
growers. EPA has also prepared a document to describe possible research and study designs to
reduce uncertainties in understanding emission factors in the context of different films and seals,
agricultural practices, and environmental conditions.7 During the 60-day comment period the
Agency anticipates learning more about ongoing and planned research from the scientific
community that will address these uncertainties to help the Agency identify potential studies that
would help refine the current risk-based mitigation decisions. The EPA will defer decisions
regarding calling-in any data to address uncertainties identified with regard to these and other
factors until comments provided during the 60-day comment period have been reviewed.
Other factors such as soil moisture content, field preparation, water sealing, and
application depth could not be used to justify credits based on the available data. However, EPA
has established mandatory good agricultural practices (GAPs) for these conditions. See the GAP
section on page 50 for further discussion. If additional data on such emission reduction methods
becomes available, EPA will consider developing further credits.
Buffer Zone Impacts
EPA acknowledges that even with the use of credits, there could be significant economic
impacts to some growers who may not be able to accommodate large buffers based on their
current application practices. As part of the most recent public comment period on fumigant risk
assessments and proposed mitigation, several stakeholders submitted analyses estimating the
impact of buffer zones around fumigated agricultural fields. The Agency's review of these
studies and discussion of an EPA contracted study using the same approach for Kern County,
California is included in the docket8. While buffers may restrict certain application practices,
this decision allows growers the flexibility to modify their practices to achieve smaller buffers;
for example treat smaller application blocks, or switch to a lower emission application method.
Available data indicate that for some crops and regions, pest control efficacy may be improved
with high barrier tarps which may enable growers to use the buffer zone credits and utilize lower
application rates, resulting in further reductions of the buffer zone distances. Some growers in
the Southeast are commonly using high barrier tarps and lower rates at present.
The Agency has also looked at how buffer zones have impacted California practices8.
Buffer zones are currently required in California for methyl bromide pre-plant soil fumigations,
as well as for dazomet use on strawberries and tomatoes. The Agency's document explains how
7 Health Effects Division Recommendations for Fumigant Data Requirements. June 2008. DP Barcode 353724
8 Review of Stakeholder Submitted Impact Assessments of Proposed Fumigant Buffers, Comments on Initial Buffer
Zone Proposal, and Case Studies of the Impact of a Flexible Buffer System for Managing By-Stander Risks of
Fumigants (DP# 353940)
36
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California strawberry growers have modified their fumigation practices as a result of the buffer
zones, and also the impact of these changes.
2. Posting
Posting is recognized as an effective means of informing workers and others about areas
where certain hazards and restrictions exist. Current soil fumigant labels require treated areas to
be posted, and handlers are required to wear specific PPE when they are in a treated area. For
buffer zones to be effective risk mitigation, bystanders, including agricultural workers in nearby
areas, need to be informed of the location and timing of the buffer to ensure they do not enter
areas designated as part of the buffer zone.
In addition to alerting bystanders, posting a buffer zone will help handlers determine
where and when they are required to use PPE. As described below, handlers working in buffers
during the buffer zone period must use label-specified PPE and meet other requirements under
the Worker Protection Standard (WPS). Therefore, EPA has determined that to ensure the
protectiveness of buffers for bystanders and handlers, the perimeter of the fumigant buffer zones
must be posted as described below and in the example that follows.
Posting of a buffer zone is required except when one of the following conditions exist:
(1) a physical barrier that is reasonably likely to prevent bystander access to the buffer
zone (e.g., a fence or wall) separates the edge of the buffer zone from bystander access.
OR
(2) the area within 300 feet of the edge of the buffer zone is controlled by the application
block owner/operator. That is, if land under someone else's control is within 300 feet
from the edge of the buffer zone, the buffer zone must be posted.
A buffer within 300 feet of an area that includes worker housing must be posted even if
the area is under the control of the land owner/operator.
Buffer zone posting signs must:
o Be placed at all usual points of entry and along likely routes of approach from areas
where people not under the land operator's control may approach the buffer zone.
o When there are no usual points of entry, be posted in the corners of the buffer zone,
between the corners of the buffer zone, and along sides so that one sign can be
viewed (not read) from the previous one. Some examples of points of entry include,
but are not limited to, roadways, sidewalks, paths, and bike trails.
Buffer zone posted signs must meet the following criteria:
o The printed side of the sign must face away from the treated area toward areas from
which people could approach.
o Signs must remain legible during entire posting period and must meet the general
standards outlined in the WPS for text size and legibility (see 40 CFR §170.120).
o Signs must be posted before the application begins and remain posted until the buffer
zone period has expired.
37
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o Signs must be removed within 3 days after the end of the buffer zone period.
o Registrants must provide generic buffer zone posting signs which meet the criteria
above at points of sale for applicators to use.
Exception: If multiple contiguous blocks are fumigated within a 14-day period, the entire
periphery of the contiguous blocks' buffer zones may be posted. The signs must remain posted
until the last buffer zone period expires and signs may remain posted until 3-days after the buffer
zone period for the last block has expired.
Additional requirements for treated area posting:
The treated area posted signs must remain posted for no less than the duration of the entry
restricted period after treatment.
Treated area signs must be removed within 3 days after the end of the entry-restricted
period.
Signs must meet the general standards in the WPS for placement, text size, and location
(40CFR§170.120).
Contents of Signs
The treated area sign (currently required for
fumigants) must state the following:
~ Skull and crossbones symbol
The buffer zone sign must include the
following:
Do not walk sign
- "DANGER/PELIGRO,"
~ "Area under fumigation, DO NOT
ENTER/NO ENTRE,"
~ "[Name ofjumigant] Fumigant in USE,"
~ the date and time of fumigation,
~ the date and time entry prohibition is lifted
~ Name of this product, and
~ name, address, and telephone number of the
certified applicator in charge of the fumigation.
- "DO NOT ENTER/NO ENTRE,"
~ "[Name offumigant] Fumigant BUFFER
ZONE,"
~ the date and time of fumigation,
~ the date and time buffer zone restrictions are
lifted (i.e., buffer zone period expires)
~ Name and EPA registration number of the
product applied, and
~ name, address, and telephone number of the
certified applicator in charge of the fumigation
To clarify the posting requirements, the following example has been included.
38
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Figure 3* Posting Example
Ruder zone
100 ft
350 ft
Property
Operator's
Residence
Red Houses = Structure within 300 feet of the buffer zone edge. Yellow dots = posted signs
* The structures in are (1) within 300 feet of the edge of the buffer zone, and (2) there
is no physical barrier between the two structures and the buffer zone, and (3) the land
operator does not control these structures.
* Although the operator's (striped building) is within 100 feet of the
edge of the buffer zone, since it is controlled by the property operator, no of the
buffer zone is necessary here.
* There is a road within 100 feet of the edge of the buffer zone. Since there is a possibility
of people from the road entering the buffer zone area, the buffer zone needs to be posted
in the northwest corner.
Buffer Zone Posting Considerations
The Agency received comments on the burden for applicators to post the entire perimeter
of a buffer zone due to the large distance it covers. In an effort to reduce the burden on growers,
but retain the posting requirement for situations where people are most likely to enter a buffer
zone, EPA believes posting where people are most likely to enter buffers will be protective.
USDA also noted that as growers break their fields into smaller application blocks to result in
smaller buffer zones, the posting requirements would be burdensome in that users would need to
put up and take down signs for multiple adjacent, sequential applications. To address this
concern, EPA is allowing signs for contiguous application blocks to be placed on the of the
buffer zone area for all blocks treated within a 14-day period. EPA believes this will be
protective and potentially less burdensome.
39
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bb. Occupational Risk Mitigation
1. Handler Definition
Based on stakeholder comments, a clarification of EPA's definition of handler activities,
as currently defined in the Worker Protection Standard (WPS) and fumigant labels, is needed.
Persons engaged in any of the following activities will be defined as handlers on product labels.
Persons participating in the application as supervisors, drivers, co-pilots, shovelers, or as
other direct application participants;
Persons taking air samples to monitor fumigant air concentrations;
Persons cleaning up fumigant spills;
Persons handling or disposing of fumigant containers;
Persons cleaning, handling, adjusting, or repairing the parts of fumigation equipment that
may contain fumigant residues;
Persons installing, repairing, operating irrigation equipment in the fumigant application
block or surrounding buffer zone during the buffer zone period;
Persons entering the application site or surrounding buffer zone during the buffer zone
period to perform scouting or crop advising tasks;
Persons installing, perforating (cutting, punching, slicing, poking), removing, repairing,
or monitoring tarps - until
o After tarps are perforated and removed if tarp removal is completed less than 14 days
after application, or
o 14 days after application is complete if tarps are not perforated and removed during
those 14 days, or
o 48 hours after tarps are perforated if they will not be removed prior to planting.
2. Handler Requirements
Since many fumigant incidents are caused by human error and equipment failure, EPA
believes the presence of onsite trained personnel would help to reduce these risks. Therefore, a
certified applicator must maintain visual contact with any fumigant handler during the entire
period while the fumigant is being incorporated into the soil. The person monitoring other
handlers may also be engaged in fumigant handling tasks during the monitoring period and two
qualified monitors may monitor one another simultaneously.
Before applying this product the certified applicator supervising that application must
have, within the preceding 12 months, successfully completed a dazomet training program made
available by the registrant (see the Soil Fumigation Training for Applicators and Other Handlers
section on page 60). The Fumigant Management Plan, discussed later in this document must
document when and where the training program was completed.
For cases when the certified applicator leaves the site after the application portion of the
fumigation process is complete and other parties will be performing handler tasks (e.g., tarp
cutting/removal, water application, etc.), the certified applicator must communicate in writing to
40
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the site owner/operator and other handlers key information needed to comply with label
requirements (e.g. PPE requirements, location of buffers, when buffer zone ends, reentry
restrictions, minimum times for cutting tarps, etc.).
When handlers are fixing tarps, moving irrigation equipment or performing other
handling tasks as defined above, the Agency is requiring at least two WPS trained handlers be
present for all activities. Due to the volatile nature of the fumigants there is a possibility that
handlers could be overcome with the vapors and have difficulty leaving the area while they are
performing handling tasks. Therefore, EPA is requiring at least two WPS trained handlers be on
site during all post-fumigation handling activities.
3. Dermal Protection for Handlers
The dazomet dermal risk assessment indicated potential risks of concern for handlers for
some scenarios. For handlers loading and applying dazomet for tractor drawn spreaders, there
were potential risks for short term exposures assuming applications to 80 acres per day.
According to information from the registrant in the phase 3 comments, dazomet is not typically
applied to large acres, but more typically applied to blocks 5-20 acres in size. The Agency is
prohibiting applications to block sizes over 40 acres, so the short term concerns for dermal risk
to handlers loading and applying with tractor drawn spreaders is acceptable.
For intermediate term dermal risk, there are potential risk concerns for loaders and
applicators, with MOEs below 100, the intermediate dermal LOG. MOEs for loaders range from
13 for handlers wearing baseline PPE, up to 650 for handlers using closed systems. For
applicators, there is only data for handlers applying with closed cabs, and the MOE is 52 for a 40
acre field. Due to the amount of dazomet applied, and the small area it is typically applied to, it
is not likely a single handler will be exposed to the amount assumed in the risk assessment over
the intermediate time frame of 1 to 6 months. Current dazomet labels require handlers to wear
double layers (coveralls over short-sleeved shirt and short pants) and chemicals resistant gloves
to protect from dermal exposures. The Agency does not calculate risks with this level of PPE
since there is no data to assess coveralls over short-sleeved shirt and short pants. However, since
the current labels require this level of protection, the short-term risks were acceptable and the
amount of dazomet exposure assumed in the intermediate term assessment are higher than would
be expected based on dazomet's use patterns, the Agency is requiring all handlers to wear double
layers consisting of coveralls over short-sleeved shirt and short pants with gloves. In addition,
handlers will have an option to reduce the dermal protection if application equipment (i.e.,
enclosed cabs) that provides dermal protection is used.
For hand held applications there are potential dermal risks of concern when making
applications with baseline PPE. The registrants have indicated that they will not be continuing to
support applications with hand held equipment, and labels will be amended to prohibit hand held
equipment.
4. Respiratory Protection for Handlers
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The Agency's human health risk assessment for dazomet indicates that inhalation risks
for many handler tasks exceed the Agency's LOG for the acute exposure to the parent (dazomet)
and MITC.
The Agency has received comments from applicators that respirators are not necessary
because (1) the possibility of eye irritation and the nature of the smell of MITC (i.e., sulfur,
rotten eggs) to alert handlers if there has been an unsafe exposure, (2) respirators inhibit
communication which could cause an accident; and (3) in warm weather respirators can cause
heat stress and other ailments. On the other hand, some stakeholders are in favor of mandatory
respiratory protection because there is currently no accurate, inexpensive, easy to use monitoring
equipment that is sensitive enough to show that acute levels of concern have not been exceeded.
These stakeholders have also stated based on their experience that handlers will not be given
access to respirators and other PPE unless it is required on the label.
The currently available monitoring tubes detect MITC at levels as low as 100 ppb, which
is higher than the Agency's LOG for acute exposure of 22 ppb. However, at a level of 100 ppb,
handlers would be exposed to levels of MITC that are 8 times lower than effects seen at the
LOAEL of 800 ppb from the human study, which is about equal to an MOE of about 2. In
addition, the eye effects from MITC exposure act as a biomarker or surrogate that protects for
more adverse systemic and respiratory effects. The available toxicity data in animals or humans
do not allow us to compare the dose response curves of the eye, systemic, and respiratory effects,
so there is uncertainty in how close the more adverse effects may be as compared to the eye
irritation effect. As stated in EPA's review of the endpoint selection:
"With respect to respiratory impairment, arguably, eye irritation is less severe compared to other
possible effects associated with inhalation exposure to MITC, particularly given the expected
reversible nature of the eye irritation effects at lower concentrations. Nonetheless, eye (as well as nose
and throat) irritation is uncomfortable and could potentially interfere with everyday tasks or activities.
Due to the limitations in the existing inhalation toxicology database for MITC, the degree to which eye
irritation predicts more serious outcomes is unclear. However, in the absence of more robust dose-
response data from acute exposures, eye irritation can be considered as a biomarker and surrogate for
potential respiratory effects." (D293349)
Based on (1) the reversible sensitive endpoint selected, (2) the limited monitoring
technology currently available, (3) the potentially physically stressful response to respirators, and
(4) the apparent fact that current technology allows detection at levels 8 times lower than the
LOAEL of 800 ppb selected, the Agency is allowing a monitoring program for MITC in place of
respirators for handlers, as long as detected MITC levels remain at or below 100 ppb.
Therefore, the Agency is requiring handlers potentially exposed to MITC vapors from
dazomet applications to either wear at least a half-face respirator during the handling activity, or
follow the monitoring program detailed below. For some handling tasks described below,
respirators are required to be worn at all times due to the short duration of the task and the
potentially high concentration of MITC exposure. The certified applicator supervising the
fumigant application must ensure that any handler who enters the buffer zone (including tractor
drivers, loaders, irrigators, tarp cutters, removers, etc.) is either wearing respiratory protection or
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is following the handler monitoring requirements, with respirators immediately available to each
handler.
Continuous monitoring for task over a long duration
An air purifying PF10 respirator only provides 10 times the inhalation protection from
the air concentration in an area. If a concentration of 100 ppb is measured in the breathing zone
of the handling task, then an air purifying PF10 respirator must be worn by that handler. The
respirator is designed to protect the handler from 10 times the concentrations of MITC in the air,
i.e., 100 ppb x 10 = 1000 ppb (1 ppm). At air concentrations greater than 1000 ppb the respirator
is not designed to provide continuous protection, and in such a situation, even a respirator may
not protect handlers from inhaling more than 100 ppb of MITC. Therefore, the handler must
continue to monitor once respirators are donned. If concentrations of MITC exceed 1000 ppb or
if eye irritation occurs, then the operations must cease until levels of MITC are measured to be
below 1000 ppb from consecutive air samples taken at least 15 minutes apart.
Long Duration Tasks
For handlers such as applicators supervising or making the application, tractor drivers,
tractor co-pilots, shovelers, and tarp cutters, the respiratory requirements include:
o Mandatory monitoring in the breathing zone of handlers at least once an hour,
even if a respirator is worn.
o Air-purifying respirators must be put on if one of the following occurs:
MITC concentrations are > 100 ppb, or
Handlers experience sensory irritation.
o All activities must cease if one of the following occurs:
MITC concentrations are > 1000 ppb, or
Handlers experience sensory irritation while wearing respirators.
o In order to remove the respirator or resume work activities:
Two air samples for MITC must be taken in the treatment area at least 15
minutes apart.
The samples must be less than 100 ppb to remove the respirator and below
1000 ppb for work activity to resume with a respirator.
During the collection of samples an air purifying respirator must be worn.
Respirators cannot be removed until monitoring indicates that levels have decreased
below the triggers listed above, and if handlers are not experiencing eye irritation.
Short Duration Tasks
Handlers that may be exposed to high concentrations of MITC and who are engaged in
tasks that occur over a short time frame, such as mixers/loaders, handlers installing/repairing
irrigation systems during application, irrigation operators during application, and or tarp handlers
repairing the tarp, must wear respirators at all times. No monitoring measure is required since
the scope of these tasks is relatively short in duration and the monitoring would not be effective
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in capturing spikes in MITC. However, if a handler experiences eye irritation the activity must
stop until corrective steps have been taken (e.g., add water to the application site, stop the
mixing/loading activities, etc.) to reduce the air concentration of MITC.
Additional Respiratory Requirements
In the dazomet risk assessment, a respirator was considered for MITC exposure since
there were inhalation risk concerns without additional protection. A protection factor (PF) of 10
for a half-face air purifying respirator was utilized. The protection factor is based on the
following assumptions: 1) the respirator is fit-tested, 2) proper respirator training occurs, and 3)
an annual medical evaluation and clearance is done. Without these requirements, it is unclear
whether the reduction in inhalation exposure that is assumed by the protection factor is actually
achieved. In order to ensure that the respiratory protection EPA is assuming is being achieved in
the field, respiratory requirements for MITC generators will include fit testing, respirator
training, and annual medical evaluation. In addition, respirators must be made available to all
handlers that may be exposed to MITC vapors. The language to be added to labels is listed
below and in Table 4.
"Employers must also ensure that all handlers are:
Fit-tested and fit-checked using a program that conforms to OSF£A's requirements (see
29CFR Part 1910.134)
Trained using a program that confirms to OSF£A's requirements (see 29CFR Part
1910.134)
Examined by a qualified medical practitioner to ensure physical ability to safely wear the
style of respirator to be worn. A qualified medical practitioner is a physician or other
licensed health care professional (PLHCP) who will evaluate the ability of a worker to
wear a respirator. The initial evaluation consists of a questionnaire that asks about
medical conditions (such as a heart condition) that would be problematic for respirator
use. If concerns are identified, then additional evaluations, such as a physical exam,
might be necessary. The initial evaluation must be done before respirator use begins. It
does not need to be repeated unless the health status or respirator use conditions change.
The employer of the fumigant handlers must make sure that all handlers in the application
block and the surrounding buffer zone are provided and correctly wear the required PPE. The
PPE must be cleaned and maintained as required by the Worker Protection Standard for
Agricultural Pesticides."
5. Tarp perforation and removal
The Agency's risk assessment indicates that there is a risk concern for handlers during
the perforation (cutting, poking, punching, or slicing) and removal of tarps, particularly when
high barrier tarps are used. In addition to respiratory protection requirements described above,
the Agency is requiring the following to mitigate risks from inhalation exposure:
Tarps cannot be perforated until a minimum of 5 days (120 hours) have elapsed after the
fumigant injection into the soil is complete (e.g., after shank injection of the fumigant
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product and tarps (if used) have been laid or after drip lines have been purged and tarps
have been laid, unless an adverse weather condition exists for broadcast applications).
If tarps will be removed after perforation, tarp removal cannot begin until at least 24
hours after tarp perforation is complete.
If tarps will not be removed after perforation, planting or transplanting cannot begin until
at least 48 hours after tarp perforation is complete.
If tarps are left intact for at least 14 days after fumigation injection into the soil is
complete, planting or transplanting may occur while the tarps are being perforated.
Adverse Weather Conditions Exemption for Broadcast Applications Only, see Figure 9:
Tarps may be removed before the required 5 days (120 hours) if adverse conditions will
compromise the integrity of the tarp, provided that:
o At least 48 hours have passed after the fumigant injection is complete,
o The buffer zone period is extended until 24 hours after tarp removal is complete,
and
o Subsequent fumigations of untreated areas within the application block do not
occur for at least 24 hours after tarp removal is complete.
To reduce exposure to handlers perforating tarps
o Tarps used for fumigations must be perforated only by mechanical methods.
o Perforation by hand or with hand-held tools is prohibited.
Each tarp panel used for broadcast fumigations must be perforated using a lengthwise cut.
This measure is to reduce the likelihood of the tarp blowing away prior to tarp removal.
6. Entry Prohibitions
Current dazomet labels allow reentry to the treated field by workers 24 hours after
application. The risk assessment indicates that risks could exceed EPA's LOG for workers
entering fields at this time period. Stakeholder comments indicate that non-handler entry to
perform post-application tasks is generally not needed for at least 10 to 14 days following the
completion of the application.
Due to the volatile nature of MITC and the potential for exposure to unprotected workers,
the Agency will prohibit entry into the treated area or buffer zone by anyone other than a
protected handler. The prohibition differs from a Restricted Entry Interval (REI) that are
currently required for most conventional pesticides which contains exceptions for workers doing
certain tasks before the REI has expired (e.g., scouting). Workers permitted entry under the REI
are prohibited for soil fumigants.
EPA believes that risks will not exceed the Agency's LOG provided entry (including
early entry that would otherwise be permitted under the WPS) by any person - other than a
correctly trained and PPE-equipped handler who is performing a handling task - is prohibited
from the start of the application until:
5 days (120 hours) after application has ended for untarped applications, or
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After tarps are perforated and removed if tarp removal is completed less than 14 days
after application, or
48 hours after tarps are perforated if they will not be removed prior to planting, or
5 days (120 hours) after application is complete if tarps are not perforated and removed
14 days after the application is complete.
Figures 4, 5, 6, 7, and 8 provide a graphical depiction of mitigation required to mitigate worker
risk in various fumigant application scenarios.
Figure 4. Untarped Application
5 (120
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Figure 5. Tarps removed before planting
Tsrp Rerofival
Begins
Taip RetnmraJ
Ends
Figure 6. Tarps NOT Removed Before Planting
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Figure 7. Tarps NOT Removed Before Planting and NOT punched until 14 days after the
application
Figure 8. Adverse Weather Conditions Exemption (Broadcast tarp applications ONLY)
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cc. Other Risk Mitigation
Below are requirements for FMPs, GAPs, emergency preparedness and response, notice
to lead agencies, training, and community outreach and education that the Agency concludes are
needed to mitigate risks and the likelihood of incidents caused by human error, equipment
failure, and weather events such as temperature inversions.
1. Restricted Use Classification
All soil fumigant products containing methyl bromide, 1,3-dichloropropene (1,3-D),
iodomethane, and chloropicrin are currently classified as RUPs. Soil fumigant products
containing dazomet and metam sodium/potassium are currently unclassified. However, MITC,
the byproduct of dazomet and metam sodium/potassium, has characteristics that meet the criteria
for restricted use for both human hazard criteria (as specified in 40 CFR 152.170(b)) and from
other evidence (as specified in 40 CFR 152.170(d)) the use history and incident data from
exposure to MITC.
Human Hazard Criteria
The acute toxicity profile of MITC shows it is more acutely toxic (toxicity categories are
all I or II) than dazomet (mostly toxicity categories III and IV. While the product toxicity of
dazomet does not meet the hazard criteria for classification as restricted use, the degradate
product of MITC, that both handlers and bystanders can be exposed to, does meet the criteria.
Other Evidence
If any soil fumigant is not applied correctly, bystanders may be exposed to concentrations
that exceed levels of concern and that could cause significant adverse effects. There is a history
of incidents involving fumigants in which multiple bystanders experienced illness/injury despite
being several hundred to several thousand feet from the treated area. The application of soil
fumigants can pose risk for several hours from the time of application to several days after
application. Depending on the situation, worker and/or area air monitoring may be required to
ensure that exposure limits are not exceeded. Special equipment is often needed to apply soil
fumigants safely and accurately (e.g., compaction rig, tarp equipment, and self-contained
breathing apparatus). To apply soil fumigants safely and ensure bystanders and applicators are
not adversely affected, handlers also need specialized competencies.
In sum, dazomet meets the standard for restricted use because:
The application of fumigants involves complex operations requiring specialized training
and/or experience.
Fumigant label directions call for specialized apparatus and protective equipment that is
not available to the general public.
A minor failure to follow label directions may result in severe adverse effects.
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Even if directions for use are followed, use may result in discernible adverse effects, of
both direct and indirect nature, on non-target organisms.
Therefore, the Agency has determined that all dazomet soil fumigant products must be classified
as restricted use. Label requirements will include the following, which is also contained in Table
4.
Requirement on Labels
"Restricted Use Pesticide Due to acute inhalation toxicity to humans."
"For retail sale to and use by Certified Applicators or persons under their direct supervision and
only for those uses covered by the Certified Applicator's certification."
In order to ensure that a certified applicator is at the application site, the label will also
state, "the certified applicator supervising the application must be at the fumigant application site
and able to maintain visual contact with every handler participating in the application starting
when the fumigant is first introduced into the soil and ending after the fumigant has stopped
being delivered/dispensed to the soil and the soil is sealed."
2. Good Agricultural Practices
Since the application methods and work practices of the handlers have direct impact on
the amount of fumigant applied and emitted, the Agency believes that labeling should describe
proven practices that will reduce risks to handlers, bystanders, and the environment. Registrants,
applicators, growers, and other stakeholders have consistently reported to the Agency that good
agricultural practices (GAPs) are the best mitigation measure to reduce the amount of fumigants
applied and emitted.
The following are mandatory GAPs that already appear on dazomet product labels. Some
of the measures have been updated to clarify the language and be consistent among the fumigant
chemical product labels.
Do not use dazomet when the soil temperature is extremely high (over 90° F at 2"deep).
Do not apply dazomet if ambient air temperature exceeds 103° F.
Do not apply within 3-4 feet of growing plants or closer than the drop line of trees and
large shrubs. If slopes are treated with this product, take precautions to prevent the
chemical from washing downward to growing plants.
The area intended for treatment should be in seedbed condition with a fine tilth, free of
clods. Do not apply dazomet to dry or improperly tilled soil. Repeated cultivation before
treating will improve control of perennial weeds. Ditching around the site will prevent
weed seeds, nematodes, and fungi from washing into the treated area and contaminating
it.
For optimal effect, the soil to be fumigated must have sufficient moisture for good plant
growth (at least 50% field capacity) for 5-14 days (depending on temperature) before the
treatment.
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After application, the soil must be kept uniformly moist for 5-7 days. As soon as possible
after incorporation, the soil must be sealed to retain the concentration of gases in the soil
which can be achieved by:
o Compacting the soil surface after incorporation with a roller attached behind the
compacting implement.
o Moistening the surface after incorporation so a crust forms.
o Lightly moistening the soil on the third and fourth days after treatment in case the
weather dries out the soil surface to avoid surface cracks.
o In difficult situations best results may be obtained by tarping the treated area.
Do not store dazomet in an open spreader overnight.
Do not apply dazomet when wind may cause granules to drift from target area.
Do not apply dazomet through any type of irrigation equipment.
Before using dazomet be aware that the three most critical factors for a successful
fumigation program are: soil preparation, soil temperature, and soil moisture.
In addition to the statements that may already appear on dazomet soil labels, the
following weather condition statements must be added to all labels.
Weather Conditions
Prior to fumigation the weather forecast for the day of the application and the 48-hour period
following the fumigant application must be checked.
Do not apply fumigant if ground-level winds are less than 2 mph.
Applications must not occur during a temperature inversion or when temperature inversions
are forecasted to persist for more than 6 consecutive hours for the 36-hour period after
application.
o Visual features indicating an inversion include misty conditions which occur anytime
or clear skies with stars visible at night.
Detailed local forecasts for sky conditions, weather conditions, wind speed, and forecasted
temperature inversions may be obtained on-line at http://www.nws.noaa.gov.
For further guidance, contact the local National Weather Service Forecasting Office.
All measurements and other documentation planned to ensure that the mandatory label
requirements are achieved must be recorded in the FMP and/or the post application summary
report.
3. Fumigant Management Plans (FMPs)
The Agency is requiring FMPs to be completed before a fumigant application occurs.
FMPs will reduce risks by requiring that applicators develop a series of performance criteria for
their given application situation. These criteria are intended to minimize risks according to the
Agency's guidance provided below. Applicators must then review those criteria before a
fumigant application occurs. The FMPs will also require that applicators verify compliance with
the criteria after application events are completed. In cases where errors may have occurred, a
post-application summary may also prevent similar problems from occurring during future
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applications. As an additional benefit, the Agency believes FMPs will ensure directions on the
product labels have been followed and that the conditions for the fumigation are documented.
FMPs should aide in the proper response of the applicator or others involved in the
application should an incident occur. A proper and prompt response will reduce the potential
risk to bystanders from high exposure situations (e.g., readily available first responder contact
information could reduce response times to impacted bystanders).
There is information from various sources that health and safety plans, FMPs in this
context, typically reduce workplace injuries and accidents by prescribing a series of operational
requirements and criteria. In fact these plans are widely implemented in a variety of industries
and are recommended as standard approaches for occupational health and safety management by
groups such as American Industrial Hygiene Association9 (i.e., through "Administrative" and
"Workplace" controls). The Centers for Disease Control provides guidance for developing
health and safety plans in agricultural settings.10 The effectiveness of similar plans has also been
evaluated in the literature. Examples include "lookback" reviews conducted by the Occupational
Safety and Health Administration (OSHA) which essentially implemented standards in various
industries then reviewed their effectiveness in this process as they are required to determine
whether the standards should be maintained without change, rescinded or modified. OSHA is
required by Section 610 of the Regulatory Flexibility Act (5 U.S.C. 610) and Executive Order
12866 to conduct the lookback reviews. These reviews are conducted to make the final standards
more effective or less burdensome in achieving their objectives, to bring them into better
alignment with the objectives of Executive Order 12866, and to make them consistent with the
objectives of the Regulatory Flexibility Act. Two examples of "lookback" reviews that support
the use of FMPs for soil fumigant health and safety management include: ethylene oxide use as a
fumigant/sterilant, and grain handling facilities requirements.11
According to stakeholder comments, most of the information required for the site-specific
FMP is already being documented by users. Most industry stakeholders support mandatory
FMPs provided they are not too restrictive and do not result in an administrative burden.
Each site specific FMP must contain the following elements:
*»* General site information
> Site address or description of location,
> Site operator/owner's name, address, and, phone number
9 Ignacio and Bullock (2006) A Strategy For Assessing and Managing Occupational Exposures (Third Edition),
American Industrial Hygiene Association, AIHA Press 2700 Prosperity Avenue, Suite 250 Fairfax VA 22031 (ISBN
1-931504-69-5)
10 Karsky (2002) Developing a Safety and Health Program to Reduce Injuries and Accident Losses, Centers For
Disease Control National Ag Safety Database, available at http://www.cdc.gov/nasd/docs/d001501-
dOO 1600/dOO 1571/dOO 1571 .html
11 United States Department of Labor, Occupational Safety and Health Administration (2008) Lookback Reviews
available at http://www.osha.gov/dea/lookback.html
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> Map, aerial photo, or detailed sketch showing field location, dimensions, buffer zones,
property lines, public roads, bus stops, water bodies, wells, rights-of-ways inside buffers,
nearby application blocks, surrounding structures (occupied and non-occupied), locations
of posted signs for buffers, and sites requiring 1A mile buffer zones (e.g., prisons, schools,
hospitals, state licensed day care centers) with distances from the application site labeled
Applicator information (license #, address, phone, contact information for person supervising
the fumigation)
Authorized on-site personnel (Names of all handlers and the tasks they are authorized and
trained to perform)
Application procedures
> Fumigation window (target application date, earliest and latest possible date of
fumigation, duration of fumigation)
> Product information (brand name, registration number)
> Type of fumigation (e.g., shank, broadcast, drip, raised bed, strip, etc.)
> Target application rate and application block size
Good Agricultural Practices (GAPs)
> Description of applicable mandatory GAPs (registrants may also include optional GAPs)
> Measurements and other documentation planned to ensure GAPs are achieved (e.g.
measurement of soil and other site conditions; tarp repair/perforation/removal plans; etc.)
Buffer zones
> Calculations and rationale for buffer zones distances (e.g. specify table from label that
distances are based on, rate and block size, applicable credits)
> Start and stop times for buffer zones
Respirators and other personal protective equipment (PPE) for handlers (respirator type,
respirator cartridge, and other PPE selection; identification of tasks that require respirators;
verification that respirator training/fit-testing/medical exams is current; and
maintenance/storage procedures)
Air monitoring
> Type of samples that will be collected (e.g., occupational, in occupied structures, outside
buffer zone if fumigation site monitoring is conducted, etc.)
> When and where samples will be collected
> Duration of samples
> Sampling methods and equipment
> Name, address, and, phone number of person taking samples
Posting (names of persons who will post signs, location of posting signs, procedures and
timing for posting and sign removal)
Site specific response and management
> Fumigation site monitoring
Description of who, when, where, and procedures for monitoring buffer zone
perimeter
> Response information for neighbors
List of residences and businesses informed (neighboring property owners)
Method of sharing information
State and tribal lead agency notification
> Include information that is sent to the lead agency
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»«» Plan describing how communication will take place between applicator, land owner/operator,
and other on-site handlers (tarp cutters/removers, irrigators, etc.)
»»» Record keeping procedures
»»» Emergency procedures (evacuation routes, locations of telephones, contact information for
first responders, local/state/federal contacts, key personnel and emergency
procedures/responsibilities in case of an incident, equipment/tarp/seal failure, odor
complaints or elevated air concentration levels outside buffer zone suggesting potential
problems, or other emergencies).
»«» Hazard communication (product labels, material safety data sheets, etc.)
For situations where an initial FMP is developed and certain elements do not change for
multiple fumigation sites (e.g. applicator information, authorized on-site personnel, record
keeping procedures, emergency procedures, etc.) only elements that have changed need to be
updated in the site-specific FMP provided the following:
The certified applicator supervising the application has verified that those elements are
current and applicable to the application block before it is fumigated and has documented
the verification in the site-specific FMP.
Recordkeeping requirements are followed for the entire FMP (including elements that do
not change)
Once the application begins, the certified applicator and owner/operator of the application
block must provide a copy of the FMP to handlers who are involved in the fumigation, workers
in adjacent areas to the application block, and Federal/State/local enforcement personnel, upon
request.
Within 30 days of completing the application portion of the fumigation process, the
certified applicator supervising the application must complete a post fumigation application
summary that describes any deviations from FMP that have occurred, measurements taken to
comply with GAPs as well as any complaints and/or incidents that have been reported to
him/her. The summary must include the actual date of the application, application rate, and size
of application block fumigated. This summary must be kept along with the FMP.
In addition to recordkeeping requirements from 7 CFR part 110 "Recordkeeping
Requirements for Certified Applicators of Federally Restricted Use Pesticides," this decision
requires that both the applicator and owner/operator of the application block must keep a signed
copy of the site-specific FMPs and the post-application summary record for 2 years from the date
of application.
Applicators and other stakeholders have the flexibility to prepare FMPs templates or use
software with certain elements listed above in check-list and/or fill in the blank format. Below
are examples of other FMP templates available on the internet for structural fumigations that
may be useful to users when developing FMPs for dazomet soil applications:
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http://www.cardinalproproducts.com/Misc/FMP%20Version%203.pdf
http://www.pestcon.com/techlibrary/fum_mgmt_plan.doc
http://www.agr.state.ne.os/division/bpi/pes/fomigation ...... plan2.pdf
http://nmdaweb.nmsu.edu/pesticides/Management%20Plans%20Required%20for%20Fu
migations.html
4. Emergency Preparedness and Response
EPA believes measures for ensuring preparedness for situations when accidents or
emergencies occur are an important part of the suite of measures necessary to address risks posed
by fumigants. Therefore, EPA is requiring such measures at the community level in the form of
education for first responders, and information for specific sites to ensure early detection and
quick response to situations as they arise.
Although EPA believes buffers and other mitigation will prevent many future incidents, it
is likely that some incidents will still occur due to accidents, errors, and/or unforeseen weather
conditions. Early detection and appropriate response to accidental chemical releases is an
effective means of reducing risk, as well as addressing the source of the release. Reducing risks
associated with incidents that may occur in the future is a key part of EPA' s soil fumigant
decisions. By combining buffers with GAPs, FMPs, and effective emergency response, EPA is
able to reach a "no unreasonable adverse effects" finding under FIFRA.
To ensure that appropriate response mechanisms are in place in the event of a fumigant
exposure incident, EPA is requiring that registrants provide training and information, in the
context of their community outreach and education programs (see the Community Outreach and
Education section on page 64), to first responders in high-fumigant use areas and areas with
significant interface between communities and fumigated fields. In addition, applicators must
provide on-site monitoring of buffer zone perimeters in areas where residences and other
occupied structures are present. As an alternative to on-site monitoring, applicators may provide
emergency response information directly to neighbors. Each element is discussed in more detail
below.
First Responder Education
EPA is requiring registrants through their community outreach and education programs
(see the Community Outreach and Education Section on page 64), to ensure that emergency
responders have the training and information that they need to effectively identify and respond to
fumigant exposure incidents. EPA believes this will help ensure, in the case of a fumigant
accident or incident, that first responders recognize the exposure as fumigant related and respond
appropriately. The information/training to be provided to first responders will include: how to
recognize the early signs and symptoms of fumigant exposure, how to treat fumigant exposures,
how fumigant exposure differs from other pesticide exposure, plus the material safety data
sheet(s) (MSDS) for the fumigant(s) applied.
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The Agency is interested in comments from state and/or local officials about the extent to
which first responders are currently receiving information on soil fumigants, for example can
they recognize fumigant exposures, and are they aware of the appropriate steps to take to
mitigate the exposures and address the source of the exposure. In California, for example, where
soil fumigation is common in many areas, the state administers training and education for first
responders to help raise awareness and improve skills in responding to incidents. If registrants
can document that effective state programs are already in place, additional training may not be
required. However, registrants must work with state and local emergency response coordinators
to identify needs and opportunities to supplement any information already included in state and
local training for first responders about soil fumigants specifically.
Site Specific Response and Management
Fumigation Site Monitoring
EPA has determined that monitoring of the buffer zone perimeter would be an effective
approach to protect bystanders. Under this approach, if measured concentrations anywhere along
the buffer perimeter reach a LOG specified on product labels, or if the person monitoring the air
concentrations experiences eye irritation, an early sign of exposure to concentrations that exceed
the Agency's LOG, then the emergency response plan stated in the FMP (see the FMP section on
page 51) must be implemented. If other problems occur, such as a tarp coming loose, then the
appropriate control plan must be activated. Because data indicate that peak concentrations
sometimes occur on the second day following applications, EPA decided that this monitoring
must be done for the full buffer zone period to ensure concentrations do not exceed the action
level which will be specified on product labels.
Specific requirements include:
Monitoring must take place from the beginning of the fumigant application until the buffer
zone period expires.
Monitoring must be conducted by a certified applicator or someone under his/her supervision.
Monitoring of air concentration levels of the fumigant must take place in the area between the
buffer zone and the residences or other occupied structures.
The person monitoring the air concentration levels must take readings starting approximately
30 minutes from the start of application and at least once each hour during the entire
application and buffer zone period.
A direct reading detection device, such as a Draeger device with a sensitivity of at least 100
ppb for MITC must be used to monitor the air concentration levels of MITC.
If at any time (1) MITC concentrations are greater than or equal to 100 ppb, OR (2) the
person monitoring the air concentrations experiences sensory irritation, then the emergency
response plan stated in the FMP must be immediately implemented by the person monitoring
the air concentrations
If other problems occur, such as a tarp coming loose, then the appropriate control plan must
be activated.
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The results of the air concentration monitoring must be recorded in the FMP.
EPA is interested in comments from fumigant users, researchers, and equipment
manufacturers about the extent to which mechanical devices are available or are under
development that can both monitor air concentrations and also notify the person responsible for
the fumigation when air concentrations approach levels of concern. Such devices are routinely
used to monitor environmental conditions in laboratories, and could represent an effective
alternative to posting a person on site.
While protective, this site monitoring might be burdensome for users fumigating in areas
with few or no people. Therefore, EPA is allowing users the alternative option of providing
emergency response information directly to neighbors.
Response Information for Neighbors
As an alternative to on-site monitoring, the certified applicator supervising the fumigation
(or someone under his/her direct supervision) would need to ensure that residences and
businesses that meet the criteria outlined below have been provided the information below at
least 48 hours prior to fumigant application in a specified field. If after 2 weeks, the fumigation
has not yet taken place, the information must be delivered again.
Information that must be provided includes:
o Location of the application block
o Name of fumigant products(s) applied including EPA Registration number
o Applicator and property owner/operator contact information
o Location of buffer zones
o Time period in which the fumigation is planned to take place and the duration of
buffer zone period
o Early signs and symptoms of exposure to the fumigant(s) applied, what to do, and
who to call if you believe you are being exposed (911 in most cases).
The method for distributing information to neighbors must be described in the FMP and
may be accomplished through mail, telephone, door hangers, or through other methods that can
be reasonably expected to effectively inform residences and businesses within the required
distance from the edge of the buffer zone.
Who Needs to be Informed?:
If the buffer zone is
less than or equal to:
Buffer < 100 feet
100 feet < Buffer < 200 feet
200 feet < Buffer < 300 feet
People within this distance
from the edge of the buffer zone
must be informed:
50 feet
100 feet
200 feet
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Buffer > 300 feet
To clarify this option, the following example is provided:
300 feet
« IF the buffer zone is 125 feet, people within 100 feet of the buffer zone must be provided emergency
response information. So the houses would need to be informed, but the house would not.
« This requirement does not impact the roadway or the property operator's residence (striped).
Figure 9. Example Site Map for Informing Neighbors
Road-
Property
Operator's
Residence
If there are no residences or other occupied structures within 300 of the of the
buffer zone, no site monitoring or advising of neighbors will be required.
Emergency Preparedness and Response Considerations
EPA received comments from many stakeholders about the Agency's Phase 5 proposal
for notification. Users have commented that notification is burdensome and that it is
unnecessary if buffer zones are also required. However, community groups have commented on
the importance of bystanders being informed when fumigations are occurring, since this group of
pesticides, compared to other pesticides, has a greater potential to move off site and affect people
not involved in the application. State regulators have different views on this requirement. Some
support the sharing of information with neighbors, and some have notification
requirements for fumigations with certain products or for certain application methods. In
addition, some states require notification to chemically sensitive individuals in proximity to
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pesticide applications. Others also had concerns about the enforceability of this type of measure
and the possible burden on the states to enforce a notification requirement.
California currently requires notification of persons within 300 feet of a methyl bromide
buffer zone. California strawberry growers consider the 300 foot notification area for methyl
bromide applications to be an extension of the buffer zone. In areas where a large number of
people would need to be notified about a planned methyl bromide application, strawberry
growers state that they would rather not use methyl bromide because some communities could
mobilize to prevent the fumigation from taking place. Some stakeholders also commented that it
would be protective and less burdensome if EPA required the user to monitor fumigant air
concentrations at the edge of the buffer for 24 hours after the application to ensure the fumigant
does not move beyond the buffer at concentrations that exceed EPA's LOG. If concentrations of
concern were detected, the user would be required to implement the emergency response
measures specified in the fumigant management plan.
EPA has concluded that bystanders could take steps to protect themselves if they had
basic information about fumigations and the appropriate steps to take if they experienced
symptoms of exposure. In a number of fumigant incidents that have occurred, the magnitude and
severity of the incident could have been significantly reduced if people had such information.
Similarly, having on-site monitoring will enable site managers to take remedial action (i.e.,
activate the control plan in the FMP) to lower emissions sooner, also resulting in fewer and less
severe exposures. And, if necessary, site managers would activate the emergency response
elements of the FMP.
Providing communities with information about local chemical releases is an important
part of emergency preparedness programs and is recognized as an effective means of addressing
risk at the local level. Some states, like Florida and Wisconsin, have requirements for providing
information to chemically-sensitive individuals about chemicals used nearby so they can take
steps to protect themselves from potentially harmful exposures (see http://edis.ifas.ufl.edu/pi004
and http://www.legis.state.wi.us/rsb/code/atcp/atcp029.pdf). Wisconsin also requires fumigators
applying metam sodium products through chemigation to provide written notice to the county
public health agency and to every individual or household within Vi miles of the chemigation
application site (see lM^Mwwy!Ll^^M&^A^§/I^lcQde/^c^/at£^Q3Q^d[). EPA agrees that
information about how to recognize and address exposures can help citizens reduce potential
risk.
EPA understands that difficult challenges exist when agricultural land borders urban or
suburban communities. While EPA's decisions for the fumigants will not alleviate challenges
that already exist, EPA is allowing options for ensuring emergency preparedness in an effort to
lessen potential impact on growers.
If users opt, based on their site conditions, to provide emergency response information to
neighbors rather than monitor, EPA believes that scaling the size of the informed area will be
protective and helps address concerns expressed by some fumigant users. When the informed
area is scaled to the size of the buffer, small buffers which generally result from applications to
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small areas, at low application rates, and/or using low-emission application techniques, will have
small or no areas to inform, while larger applications will have larger areas to inform.
EPA is not requiring a specific method of providing the information to neighbors, but
rather that it be done in a way that effectively communicates, in a manner the recipients will
understand. Some methods may not result in documentation that would be retained. To address
concerns about enforcement, EPA is requiring that information on how and when the emergency
response information was delivered and to whom, be included in the FMP.
EPA is interested in input on the importance and usefulness of information specifying the
location of the application block and buffer. EPA recognizes that such information may be
difficult to convey clearly and concisely, especially if there are no easily recognizable land
marks nearby. While such information may be helpful, it may not be critical to ensuring an
appropriate response to early signs and symptoms of exposure.
5. Notice to State Lead Agencies
EPA believes that when state, tribal and local enforcement officials have information
about when and where applications take place they are better able to plan and execute
compliance assistance and assurance activities. Therefore, EPA is requiring notification of the
appropriate state or tribal lead agency before an application begins to assist enforcement
agencies in compliance monitoring.
The information that must be provided includes the following:
o Applicator contact information (name, telephone number, and applicator license
number)
o Property owner/operator contact information
o Location of the application block
o Name of fumigant(s) products(s) applied including EPA Registration number
o Time period in which the fumigation is planned to take place and the duration of
buffer zone period
Assuring compliance with new label requirements is an important component of the
fumigant risk mitigation package. Notice to enforcement officials allows them to target
inspections around periods when fumigations are expected to occur to ensure label requirements
designed to mitigate risks of concern for bystanders, handlers, and workers, have been followed
and that the conditions for the fumigation have been documented in the FMP. In states such as
California, where permitting processes are already in place, additional notice to state and tribal
lead agencies will not be required.
6. Soil Fumigation Training for Applicators and Other Handlers
Soil fumigation is an inherently complex activity involving specialized equipment and
application techniques. Additionally, the mitigation measures required as part of these decisions
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will introduce new requirements in the form of more detailed instructions and restrictions on soil
fumigations. Failure to adequately manage fumigant applications increases risks to handlers
involved in the fumigation, workers nearby, and other bystanders. Incident data show that a
number of fumigant incidents are the result of misapplications, failure to follow label
requirements and safe use procedures, and other errors on the part of fumigant applicators.
Although states have certification programs, some of which include a specific category for soil
fumigation, there currently is not a consistent standard across states and regions where soil
fumigation is done, and the federal certification program currently has no category for soil
fumigation. Proposed changes in the federal certification program and worker safety regulations
to include a soil fumigation category are not, however, anticipated in the near future.
EPA believes that training is an effective way to increase applicators' skill and
knowledge so they are better prepared to effectively manage soil fumigation and are able to
understand and comply with revised labeling. EPA has determined that training, developed and
implemented by registrants to foster product stewardship, will help reduce potential risks
associated with failure to adequately manage the complexities of fumigation, and failure to
comply with fumigant product labeling. Additionally, EPA believes that providing safety
information to other fumigant handlers will help them understand and adhere to practices that
will help handlers protect themselves from risks of exposure.
It is important to note that training developed and provided by registrants as required by
this RED is separate and distinct from state certification programs. EPA encourages registrants,
in developing their training proposals, to work with states where their products are used to
identify opportunities to build on and complement state programs. However, the training
programs required as part of this decision will be separate from the state certification process and
will be developed and administered by registrants. Individual state regulatory agencies have the
option of working with registrants on these activities, but are not required to do so. It is
important to note that some fumigant registrants have already developed product-specific
training that will serve as a good basis for this expanded effort.
Training for Applicators Supervising Fumigations
Registrants will be required to develop and implement training programs for applicators
in charge of soil fumigations on the proper use of and GAPs for soil fumigants. EPA is requiring
registrants to submit proposals for these programs as data requirements in the Data Call-In that
will accompany this RED. The training programs must address, at minimum, the following
elements: how to correctly apply the fumigant; how to protect handlers and bystanders; how to
determine buffer zone distances; how to develop a FMP and complete the post fumigation
application summary; how to determine when weather and other site-specific factors are not
favorable for fumigant application; how to comply with required GAPs and document
compliance in the FMP. The training program must be made available to applicators at least
annually. The registrant shall provide documentation, such as a card or certificate, to each
applicator who successfully completes the training. This documentation shall include the
applicator's name, address, license number, and the date of completion.
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The registrant must be able to provide to federal, state, or local enforcement personnel,
upon request, the names, addresses, and certified applicator license numbers of persons who
successfully completed the training program, as well as the date of completion. Applicators
supervising fumigations must have successfully completed the program within the preceding 12
months and must document when and where the training program was completed in the FMP.
The registrants will be required to (1) develop a database to track which certified applicators
have successfully completed the training and (2) make this database available to state and/or
federal enforcement entities upon request. In addition, the applicator must provide to Federal,
State, or local enforcement personnel, upon request, documentation that verifies completion of
the appropriate training program(s).
Product labels will state that before applying the product, the certified applicator
supervising the application must have successfully completed, within the preceding 12 months, a
dazomet training program made available by the registrant, and that the FMP must document
when and where the training program was completed.
EPA encourages registrants to include in their proposals additional stewardship elements
such as technical support information and resources for certified applicators and/or handlers;
hotlines to answer technical questions from applicators about product use, emergency
preparedness and response; and equipment verification programs to assist applicators with
calibration and testing of soil fumigation equipment. The Agency is soliciting input during the
post-RED comment period from states, user groups, registrants, and other stakeholders on
content and how best to implement training programs and other stewardship elements.
Training Materials for Handlers
EPA has determined that registrants must prepare and disseminate training information
and materials for other fumigant handlers, i.e., those working under the supervision of the
certified applicator in charge of fumigations. EPA is requiring registrants to submit proposals
for these materials as data requirements in the Data Call-Ins that will accompany this RED. The
training materials must address, at minimum, the following elements: (1) what fumigants are
and how they work, (2) safe application and handling of soil fumigants, (3) air monitoring and
respiratory protection requirements for handlers, (4) early signs and symptoms of exposure, (5)
appropriate steps to take to mitigate exposures, (6) what to do in case of an emergency, and (7)
how to report incidents. Registrants must provide this training information through channels
open to the public (e.g., via a website). Pesticide labels will require that applicators supervising
fumigations provide this training information to handlers under their supervision before they
perform any fumigant handling task, or they must ensure that handlers have been provided the
required information within the preceding 12 months. The label will also require that the
training information be provided in a manner that the handler can understand. Applicators
supervising fumigations must ensure the FMP includes how and when the required training
information was provided to the handlers under their supervision.
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"The certified applicator must provide fumigant safe handling information to each
handler involved in the application or confirm that each handler participating in the
application has received fumigant safe handling information in the past 12 months."
Soil Fumigation Training Considerations
In comments on fumigant risk management options, stakeholders were broadly
supportive of additional training for applicators and handlers. During the most recent comment
period, the vast majority of stakeholders, including growers, community groups, farm workers,
states, and registrants expressed strong support for increased training for applicators and other
handlers. Several comments noted that fumigant incidents affecting both fumigant workers and
bystanders could have been prevented or mitigated if applicators had better training about correct
practices and procedures.
The Agency agrees that additional training and technical support for fumigant applicators
and handlers will help educate and inform these workers, thus decreasing the likelihood of both
incidents and noncompliance. EPA believes fumigant-specific training for applicators and
handlers also will help reduce the magnitude and frequency of exposure incidents and, coupled
with the other mitigation measures described in this decision, will address risks of unreasonable
adverse effects from the use of soil fumigants.
As noted above, several states have high-quality certification programs for fumigators
which include exams to test the competency of fumigators. EPA recognized that for applicators
to become certified in those states, they must acquire the knowledge and skill necessary to pass
the exam. But several stakeholders commented that training opportunities are varied across the
country, and the scope and detail of information provided in available training is not consistent.
EPA is also concerned that information in existing programs will need to be updated as a result
of new requirements associated with this decision and the label changes which will result.
Although the federal program will be revised eventually and will establish a consistent standard,
EPA believes that registrants must play a central role in developing and delivering training in the
interim.
EPA stresses that registrant training programs will be separate from the state certification
process and will be developed and administered by registrants in coordination with EPA. EPA
will, however, work with state organizations and training experts to explore opportunities for the
registrant programs to supplement state programs to provide additional training opportunities for
fumigators. EPA will work with registrants in reviewing training program proposals and in
developing the content for the programs and materials. EPA will also work with states to
identify ways in which registrant training programs can be tailored to complement existing state
programs. EPA's goal in requiring registrant training is to add to training resources. EPA is
aware of the need to coordinate carefully with states to ensure that new training does not become
a burden on state agencies. EPA specifically requests comments from States on the best
implementation approaches to meet these goals, and plans to meet with states during and after
the public comment period to discuss options.
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The Agency also expects that FMPs will serve as tools with which fumigant users can
maintain records of their compliance with training requirements in addition to the other measures
described in this document. Thus, FMPs would serve as an additional tool for verification state
enforcement personnel to verify compliance.
7. Community Outreach and Education Programs
EPA understands from public comments, site visits, and stakeholder meetings, conducted
as part of the soil fumigant review, that there is often a fundamental lack of information and
communication within communities where soil fumigation occurs, which has raised health and
safety concerns among community members. This lack of information and communication has
led to inappropriate responses in cases where fumigants have moved off site and into
communities. This also has led in some cases to unwarranted concern and anxiety among
communities about the risks associated with the use of fumigants. The Agency believes that
outreach and education to communities where soil fumigation occurs is an important component
of the overall package of measures to address bystander risk. This outreach and education will
address the risk of acute bystander exposure by educating community members in high-use areas
about buffer zones and their characteristics and purpose; the importance of not entering these
zones; how to recognize early signs of fumigant exposure, and how to respond appropriately in
case of an incident. The first responder training discussed above is a significant part of this
program.
Therefore, the Agency is requiring registrants to develop and implement community
outreach and education programs, including programs for first responders, to address these
needs. EPA encourages registrants' proposals to work with existing community resources, such
as community health networks, for dissemination of information and implementation of their
programs. Registrants' proposals must also include criteria and a plan for identifying and
selecting the communities that will be receive outreach programs.
Community outreach and education programs must include the following elements, at
minimum: (1) what soil fumigants are and how they work, (2) what buffer zones are, (3) early
signs and symptoms of exposure, (4) appropriate steps to take to mitigate exposures, (5) what to
do in case of an emergency, and (6) how to report an incident.
EPA expects registrants' proposals for the first responder programs described above will
also be designed to integrate with existing local first-response and emergency preparedness
networks.
The community outreach and education proposal and supporting materials for
communities and first responders, as well as a plan for evaluating the effectiveness of the
programs, will be included as data requirements in the Data Call-In that will accompany this
RED.
As with the training for fumigant applicators and handlers, the community outreach and
education program that the Agency is requiring is intended to be part of the registrants' long term
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product stewardship. State governments are not required to participate in the program, but have
the option of working with EPA and registrants to develop and track this and any other
stewardship components which the registrants may include in their proposals.
iii. Environmental Risk Management
As mentioned in Section OLD, the Agency is concerned about both aquatic and terrestrial
risks. The Agency believes that mitigation measures detailed in the Human Health Risk
Mitigation Section will also reduce ecological risks. Although buffer zones and GAPs do not
directly reduce the potential risk to ecological organisms, they do provide an incentive to reduce
fumigant application rates and individual treatment areas which in turn will contribute to lower
exposure and risks for non-target organisms.
Exposure to terrestrial organisms such as birds and mammals could occur two ways, as
either oral exposure to dazomet granules or by the inhalation route of exposure to the breakdown
product of MITC. Potential exposure to aquatic organisms may occur from surface
runoff/leaching and drift (wind) of MITC.
The risk assessment identified potential acute risks of concern for birds and mammals,
since it is assumed they could be exposed to unincorporated dazomet granules. There are
uncertainties about the aquatic risks since there are no toxicity data available. Additional eco-
toxicity data are required for both dazomet and MITC.
Since dazomet is applied as a granular and watering in is required in order to activate the
product, the amount of dazomet granular left on the soil surface to which birds and mammals
could have access is not estimated in this assessment. It is likely the amount of dazomet
available to birds and mammals is less than assumed in the risk assessment due to watering in.
In addition, the registrants will lower the maximum rate for dazomet from 530 to 425 Ibs
a.i./A for all use sites, except for golf-course renovation. This rate reduction will also reduce the
potential for effects on non-target organisms. In addition, the structure of the buffer zones
required in this decision encourages growers to use the lowest rate and block size feasible in
order to establish the smallest possible buffer zone distance for an application. Although this
mitigation measure does not directly reduce the potential risk to ecological organisms, it does
provide an incentive to reduce fumigant application rates and individual treatment areas which in
turn will contribute to lower exposure and risks for non-target organisms.
Based on the fate parameters of MITC, it should not persist in terrestrial environments
because of volatilization and degradation and the available non-targeted monitoring data does not
detect MITC in the ground- water samples within the U.S.A. However, MITC is highly soluble
in water and has a low adsorption to soil which suggests that there is a potential of leaching to
shallow groundwater under flooded and saturated conditions. Also, if intense rainfall or
continuous irrigation occurs there is potential for MITC to move to surface water. The Agency
recognizes that managing soil moisture is important factor that may be used to reduce peak
emissions, and the requirements related to soil moisture described in the GAP section on page 50
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will not result in the leaching of MITC into ground or surface water. Language is required for
both tarped and non-tarped dazomet applications to minimize potential for leaching or runoff.
The specific label statements can be found in the dazomet label table, Table 4.
b. Dazomet Antimicrobial Uses
A summary of the risk mitigation measures for the antimicrobial uses of dazomet is
presented below; for further information on the antimicrobial risk assessment and mitigation,
please see these documents in the dazomet docket:
Dazomet: Revised Occupational and Residential Exposure Assessment of
Antimicrobial Uses for the Reregistration Eligibility Decision (RED) Document.
(Walls, C., Dated June 4, 2008)
Risk Mitigation Measures and Updated Label Language for the Antimicrobial Uses
of Dazomet (PC Code 035602) for the Reregistration Eligibility Decision Document.
(Garvie, H., Dated June 2 2008)
All of the dazomet antimicrobial uses are for occupational applications. These uses
include: 1) a treatment during the production of pulp and paper; 2) a materials preservative
treatment for coatings, adhesives, epoxy flooring compounds, slurries, and high viscous
suspensions; 3) a biocide treatment used during petroleum operations; 4) a biocide treatment
used in recirculating cooling water systems; and 5) a remedial wood treatment to utility poles.
Risks of Concern
All of the occupational handler inhalation, dermal and total MOEs were above the target
MOE of 100 (short-term and intermediate-term) except for the following scenarios:
Intermediate-term dermal exposure resulting from the preservation of epoxy flooring
compounds via solid open pour methods: MOE = 58
Intermediate-term total exposure resulting from the preservation of epoxy flooring
compounds via solid open pour methods: MOE = 55
Intermediate-term dermal exposure resulting from pulp and paper slimicide use via solid
open pour methods: MOE = 79
Intermediate-term total exposure resulting from pulp and paper slimicide use via solid
open pour methods: MOE = 74
Intermediate-term inhalation exposure resulting from the maintenance dose of microbe
control in large water cooling system via metering pump: MOE = 98
Intermediate-term total exposure resulting from the maintenance dose of microbe control
in large water cooling system via metering pump: MOE = 55
Risk Mitigation Measures
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1. For epoxy flooring open pour scenario- labeling language must state that the product is
not to exceed 3,500 ppm (maximum application rate of .35%) by weight of material
treated.
2. For the pulp and paper solid open pour scenario - update PPE language to state that long
sleeve coveralls will be required in addition to wearing long sleeved shirt, long pants,
shoes, socks, goggles or face shield and chemical resistant gloves.
3. For the cooling tower use: update personal protective equipment (PPE) language to state
that chemical resistant gloves are necessary, in addition to goggles or face shield.
4. For all scenarios that use metering pumps, chemical resistant gloves must be used.
5. Additional label instructions for pole treatment use requiring that pre-drilled holes are
plugged immediately after application and instructions that holes are not to be drilled
through seasoning checks.
The data requirements for dazomet's antimicrobial use and label changes are found in Section V,
beginning on page 69.
2. Endocrine Disrupter Effects
EPA is required under the FFDCA, as amended by FQPA, to develop a screening
program to determine whether certain substances (including all pesticide active and other
ingredients) "may have an effect in humans that is similar to an effect produced by a naturally
occurring estrogen, or other such endocrine effects as the Administrator may designate. "
Following the recommendations of its Endocrine Disrupter Screening and Testing Advisory
Committee (EDSTAC), EPA determined that there were scientific bases for including, as part of
the program, androgen and thyroid hormone systems, in addition to the estrogen hormone
system. EPA also adopted EDSTAC's recommendation that the Program include evaluations of
potential effects in wildlife. When the appropriate screening and/or testing protocols being
considered under the Agency's Endocrine Disrupter Screening Program (EDSP) have been
developed and vetted, dazomet may be subjected to additional screening and/or testing to better
characterize effects related to endocrine disruption.
3. Endangered Species Considerations
The Agency has developed the Endangered Species Protection Program to identify
pesticides whose use may cause adverse impacts on endangered and threatened species and to
implement mitigation measures that address these impacts. The Endangered Species Act (ESA)
requires federal agencies to ensure that their actions are not likely to jeopardize listed species or
adversely modify designated critical habitat. To analyze the potential of registered pesticide uses
that may affect any particular species, EPA uses basic toxicity and exposure data and considers
ecological parameters, pesticide use information, geographic relationship between specific
pesticide uses and species locations, and biological requirements and behavioral aspects of the
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particular species. When conducted, these analyses take into consideration any regulatory
changes recommended in this RED being implemented at that time.
The ecological assessment that EPA conducted for this RED does not, in itself, constitute
a determination as to whether specific species or critical habitat may be harmed by the pesticide.
Rather, this assessment serves as a screen to determine the need for any species-specific
assessment that will evaluate whether exposure may be at levels that could cause harm to
specific listed species and their critical habitat. The species-specific assessment refines the
screening-level assessment to take into account information such as the geographic area of
pesticide use in relation to the listed species and the habits and habitat requirements of the listed
species. If the Agency's specific assessments for the pesticidal use of dazomet result in the need
to modify use of the pesticide, any geographically specific changes to the pesticide's registration
will be implemented through the process described in the Agency's Federal Register Notice (54
FR 27984) regarding implementation of the Endangered Species Protection Program.
Risk findings are based solely on EPA's qualitative assessment for dazomet and do not
constitute "may affect" findings under the ESA. A determination that there is a likelihood of
potential effects to a listed species may result in limitations on the use of the pesticide, other
measures to mitigate any potential effects, and/or consultations with the Fish and Wildlife
Service or National Marine Fisheries Service, as necessary. If the Agency determines use of
dazomet "may affect" listed species or their designated critical habitat, EPA will employ the
provisions in the Services regulations (50 CFR Part 402). EPA plans to begin the Registration
Review process for dazomet and the other soil fumigants in 2013, which will include a
comprehensive endangered species assessment. Once that endangered species assessment is
completed, further changes to dazomet registrations may be necessary.
D. Conclusion
In this document, the Agency has described a package of mitigation measures with
elements that are designed to work together to reduce risk to human health and the environment.
The Agency believes that all of the mitigation measures required by this decision will mitigate
risks so that dazomet use will result in no unreasonable adverse effects.
Stakeholder comments and Agency analyses indicate that mitigation may impact the
benefits of fumigant use. One analysis the Agency completed quantifies the potential impact of
buffer zones.12 The Agency believes that some impact will occur in order to protect human
health and the environment from unreasonable adverse effects. EPA believes that impacts have
been minimized because the mitigation package incorporates flexibility which allows users to
make choices that minimize potential impacts. For example a current application practice might
require a large buffer that a user is not able to implement. However, instead of setting a fixed
buffer for all applications regardless of application-specific parameters, this decision allows
12 Review of Stakeholder Submitted Impact Assessments of Proposed Fumigant Buffers, Comments on Initial Buffer
Zone Proposal, and Case Studies of the Impact of a Flexible Buffer System for Managing By-Stander Risks of
Fumigants
68
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growers the flexibility to modify their practices to achieve smaller buffers; for example treat
smaller application blocks, or switch to a lower emission application method. Also, the buffer
zone reduction credits allow users to take advantage of site conditions (e.g., soil conditions) to
lessen the impact. In addition the Agency believes that flexibility decreases the impacts
associated with respiratory protection mitigation. Instead of requiring respirators for all handling
tasks, the monitoring scheme indicates when respiratory protection is needed. This mitigation is
protective of handlers while not increasing the burden to users by mandating respirators that may
hinder communication or could potentially cause heat stress.
When dazomet is used as an antimicrobial chemical the Agency believes that the required
mitigation is protective and anticipates that it will have minimal impact on the benefits. Taking
into consideration the risk and benefit assessments and stakeholder comments, the Agency
believes the mitigation required by this document will be protective and minimize impacts.
V. What Registrants Need to Do
The Agency has determined that the products containing dazomet are eligible for
reregi strati on provided that the mitigation measures and label changes identified in this RED are
implemented. EPA recognizes that the extent of the mitigation needed for dazomet will require
continued coordination among state regulatory agencies, the Agency, registrants, growers and
other stakeholders to ensure that all provisions of the RED are understood, that data are
developed and evaluated expeditiously, and that bystander and worker protection measures are
implemented as soon as practicable. EPA also acknowledges that certain provisions of the RED,
such as the worker training programs and community education, will take time to develop in
terms of both the content of the program as well as a strategy for implementation.
EPA envisions the following approximate schedule for implementation of the dazomet RED:
July 2008 Dazomet RED issued
Fall 2008 Comment period closes
Early 2009 EPA responds to comments, amends RED if appropriate
Mid 2009 EPA issues product and generic DCIs
Mid 2009 Registrants submit revised labels to EPA
Late 2009 EPA reviews/approves new labeling
During 2009 Registrants develop worker and community training and education plans
and submits to EPA
Early 2010 Products bearing new labels enter the market; training and education
programs ramp up.
2009-2012 Registrants develop data per DCI
2013 EPA begins Registration Review for dazomet and other fumigants
The Agency is issuing this decision document for dazomet, as announced in a Notice of
Availability published in the Federal Register. Due to the broad scope of the decision for the soil
fumigant group, there will be a 60-day public comment period for this document to allow
stakeholders the opportunity to review and provide comments on issues related to the
69
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implementation of the risk mitigation measures. After considering public comment, the Agency
will issue a public determination as to whether modifications to this decision are appropriate.
Labeling
Registrants will need to amend their product labeling to incorporate the label statements
set forth in the Label Changes Summary Tables 4 and 5. The Agency will consider post-RED
comments prior to finalizing labeling. The Agency anticipates that label amendments will need
to be submitted approximately 1 year from the issuance of the RED.
A. Manufacturing Use Products
1. Additional Generic Data Requirements
The generic data base supporting the reregi strati on of dazomet for the eligible uses has
been reviewed and determined to be substantially complete. However, data to characterize the
hazard of MITC, the degradate of dazomet, are not available and are necessary to confirm the
reregi strati on eligibility decision documented in this RED.
Data requirements for all dazomet uses
OPPTS
Guideline
Number
870.6200
870.3550
870.3800
870.5550
870.4200
870.4200
I
a
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inhalation study in rats. The purpose of the acute study in rats was to determine the LC50, not
for use in hazard identification for human health risk assessment. The Agency can not evaluate
the dose response relationship of irritation and systemic effects to the nose and lungs using these
studies. This information on the respiratory tract is critical for the risk assessment as the relative
sensitivity of eye irritation and more serious health outcomes is unknown. The Agency is open
to discussing MITC-specific changes to the standard neurotoxicity screening battery to ensure
that the appropriate target organs are evaluated and that relevant dose-response data would be
generated.
870.3550 - Developmental Toxicity Screening Test - Inhalation
This inhalation developmental toxicity study in rat is being requested to further
characterize the toxicity profile of this compound via the inhalation route. MITC has been
shown to travel off fields to residential areas. As such, it is appropriate to evaluate the effects of
MITC on pregnant females and their fetuses.
870.3800 - Reproduction and Fertility Effects
Two generation reproduction study in rats via inhalation with pathological evaluation of
the complete respiratory tract in offspring is needed for MITC. This inhalation reproductive
toxicity study is being requested to further characterize the toxicity profile of this compound via
the inhalation route. MITC has been shown to travel off fields to residential areas. As such, it is
appropriate to evaluate the effects of MITC on reproductive performance and to pups directly
exposed to MITC via the inhalation route. The Agency is open to discussing with the registrant
the potential for performing the new enhanced 1-generation reproductive study instead of the
standard 2-generation study.
870.5550 - Unscheduled DNA Synthesis in Mammalian Cells in Culture
This study is required to complete the genetic toxicity testing battery for MITC.
870.4200 - Chronic/Carcinogenicity Rats
870.4200 - Chronic/Carcinogenicity Mice
Carcinogenicity studies for MITC per se are not available; therefore, the carcinogenic
potential of MITC cannot be determined at this time. Although there are not expected to be
exposures of six months or longer in duration in a given year, since the same fields are often
treated every year, there is potential for exposure to occur annually for many years. Moreover,
metaplasia of the respiratory epithelium, a lesion often associated cancer, was observed after
only 28 days of exposure in the subchronic inhalation study in rats with MITC. As such EPA is
requiring inhalation carcinogenicity studies with MITC in rats and mice.
Data requirements for dazomet's soil uses
71
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a *
C/3 ;=3
H « «
OH 3 S
On 3 3
o o z
835.8100
Special
850.2300
850.1075
850.1025
850.1035
850.4225
850.4250
850.4400
850.3020
Special
Special
Special
1
Q P^
Field Volatility from Soil
Avian Acute Inhalation, MITC
Avian Reproduction, Dazomet (bobwhite quail
and mallard)
Acute Marine/Estuarine Fish, MITC
Acute Marine/Estuarine Mollusk, MITC
Acute Marine/Estuarine Shrimp, MITC
Seedling Emergence - Tier II, MITC.
Vegetative Vigor - Tier II, MITC
Aquatic Plant Growth - Tier II, MITC (3
remaining species)
Honeybee Acute Contact, MITC
Community Outreach and Education Program
Training for Applicators Supervising
Fumigations
Training Materials for Handlers
t
ORE
ECO
ECO
ECO
ECO
ECO
ECO
ECO
ECO
ECO
Special
Special
Special
835.8100 - Field Volatility from Soil
Volatility studies are required for dazomet's soil uses to determine flux for modeling
purposes of the breakdown products of dazomet, including formaldehyde.
Special - Avian Acute Inhalation, MITC
The current estimate of avian risk is based largely on the mammal assessment. This
study will enable an inhalation risk assessment specific to birds. This is critical, since avian
exposure to MITC is expected to be largely via inhalation.
850.2300 - Avian Reproduction (bobwhite quail and mallard duck), Dazomet
These studies are needed to assess potential reproductive effects in birds from exposure
to the parent dazomet in the granular formulation. Neither of the existing studies is able to
provide an overall NOAEL/LOAEL needed for risk assessment. There were problems with
mixing of the diet in both studies and the mallard study had unacceptably high embryo mortality
in the controls between day 21 and hatch. The studies indicate the possibility of severe
reproductive effects, particularly in the mallard study, which included effects prior to those
identified in the controls.
850.1075 - Acute Marine/Estuarine Fish. MITC
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The aquatic risk assessment of dazomet use is based on exposure to MITC. Given the
use patterns evaluated, marine/estuarine species could also be exposed. This study will enable a
risk assessment for marine/estuarine species exposure.
850.1025 - Acute Marine/Estuarine Mollusk. MITC
The aquatic risk assessment of dazomet use is based on exposure to MITC. Given the
use patterns evaluated, marine/estuarine species could also be exposed. This study will enable a
risk assessment for marine/estuarine species exposure. It will also improve certainty with the
endangered species risk assessment, as this test species may be more representative of
endangered freshwater mussels than the freshwater Daphnia.
850.1035 - Acute Marine/Estuarine Shrimp. MITC
The aquatic risk assessment of dazomet use is based on exposure to MITC. Given the
use patterns evaluated, marine/estuarine species could also be exposed. This study will enable a
risk assessment for marine/estuarine species exposure.
850.4225 - Seedling Emergence - Tier IL MITC
Dazomet is used in part due to the phytotoxicity of MITC at the application site. This
study will enable the assessment of risk to non-target terrestrial plants off-site. The protocol
should be modified to test using air concentrations of MITC.
850.4250 - Vegetative Vigor - Tier IL MITC
Dazomet is used in part due to the phytotoxicity of MITC at the application site. This
study will enable the assessment of risk to non-target terrestrial plants off-site. The protocol
should be modified to test using air concentrations of MITC.
850.4400 - Aquatic Plant Growth - Tier IL MITC
Only one of five tests currently available (on duckweed) is considered to be Acceptable
(Core) (MRID #45919422). The submission of data for remaining test species under this
guideline will reduce uncertainty and improve the assessment of risk to aquatic plants. For
example, the blue-green alga and green alga studies are 72-hour OECD studies that are only
accepted as Tier I screening studies.
850.3020 - Honeybee Acute Contact MITC
Although there is honeybee data for dazomet indicating that it is relatively non-toxic to
honey bees, there is a concern that MITC could be more toxic to bees. Therefore, honeybee
acute contact data is required for MITC.
Special Study - Community Outreach and Education Program
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The Agency is requiring registrants to develop and implement community outreach and
education programs, including programs for first responders, to address these needs. Community
outreach and education programs must include the following elements, at minimum: (1) what
soil fumigants are and how they work, (2) what buffer zones are, (3) early signs and symptoms
of exposure, (4) appropriate steps to take to mitigate exposures, (5) what to do in case of an
emergency, and (6) how to report an incident. EPA expects registrants' proposals for the first
responder programs described in Section IV will also be designed to integrate with existing local
first-response and emergency preparedness networks.
Special Study - Training for Applicators Supervising Fumigations
EPA has determined that training, developed and implemented by registrants to foster
product stewardship, will help reduce potential risks associated with failure to adequately
manage the complexities of fumigation, and ensure compliance with fumigant product labeling.
Additionally, EPA believes that providing safety information to other fumigant handlers will
help them understand and adhere to practices that will help handlers protect themselves from
fumigant exposure.
Registrants are required to develop and implement training programs for applicators in
charge of soil fumigations on the proper use of and GAPs for soil fumigants. EPA is requiring
registrants to submit proposals for these programs. The training programs must address, at
minimum, the following elements: how to correctly apply the fumigant; how to protect handlers
and bystanders; how to determine buffer zone distances; how to develop a FMP and complete the
post fumigation application summary; how to determine when weather and other site-specific
factors are not favorable for fumigant application; how to comply with required GAPs and
document compliance in the FMP. The training program must be made available to applicators
at least annually. The registrant shall provide documentation, such as a card or certificate, to
each applicator who successfully completes the training. This documentation shall include the
applicator's name, address, license number, and the date of completion.
The registrant must be able to provide to federal, state, or local enforcement personnel,
upon request, the names, addresses, and certified applicator license numbers of persons who
successfully completed the training program, as well as the date of completion. Applicators
supervising fumigations must have successfully completed the program within the preceding 12
months and must document when and where the training program was completed in the FMP.
The registrants will be required to (1) develop a database to track which certified applicators
have successfully completed the training and (2) make this database available to state and/or
federal enforcement entities upon request. In addition, the applicator must provide to Federal,
State, or local enforcement personnel, upon request, documentation that verifies completion of
the appropriate training program(s).
Special Study - Training Materials for Handlers
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EPA has determined that registrants must prepare and disseminate training information
and materials for other fumigant handlers, i.e., those working under the supervision of the
certified applicator in charge of fumigations. The training materials must address, at minimum,
the following elements: (1) what fumigants are and how they work, (2) safe application and
handling of soil fumigants, (3) air monitoring and respiratory protection requirements for
handlers, (4) early signs and symptoms of exposure, (5) appropriate steps to take to mitigate
exposures, (6) what to do in case of an emergency, and (7) how to report incidents. Registrants
must provide this training information through channels open to the public (e.g., via a website).
Pesticide labels will require that applicators supervising fumigations provide this training
information to handlers under their supervision before they perform any fumigant handling task,
or they must ensure that handlers have been provided the required information within the
preceding 12 months. The label will also require that the training information be provided in a
manner that the handler can understand. Applicators supervising fumigations must ensure the
FMP includes how and when the required training information was provided to the handlers
under their supervision.
Data requirements for dazomet's antimicrobial uses
Chemical Manufactures Association (CMA) unit exposure data to be called in:
GLN 875.1200 - dermal indoor exposure
GLN 875.1400 - inhalation indoor exposure
GLN 875.1600 - applicator exposure monitoring data reporting
GLN 875.1700 - product use information
Because dazomet degrades into MITC, the Agency needs MITC air concentration monitoring
data for all enclosed facilities that utilize dazomet. The guideline numbers are as follows:
GLN 875.2500 - inhalation exposure study
GLN 875.2700 - product use information
GLN 875.2800 - description of human activity
GLN 875.2900 - post-application data reporting and calculations
Residue data are needed to support the dazomet antimicrobial use in pulp and paper
manufacturing. The purpose of this confirmatory study is to demonstrate that the paper
manufacturing processes remove any residual dazomet and MITC - GLN 860.1520
Avian acute oral LDso data using technical MITC to bobwhite quail or mallard duck - GLN
850.2100
Acute estuarine fish LCso data using technical MITC - GLN 850.1075
Acute mysid shrimp using technical MITC - GLN 850.1035
Acute bivalve embryo larvae using technical MITC to Eastern oyster - GLN 850.1055
2. Labeling for Manufacturing-Use Products
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To ensure compliance with FIFRA, manufacturing use product (MUP) labeling must be
revised to comply with all current EPA regulations, PR Notices, and applicable policies. The
MUP labeling must bear the labeling contained in Tables 4 and 5.
B. End-Use Products
1. Additional Product-Specific Data Requirements
Section 4(g)(2)(B) of FIFRA calls for the Agency to obtain any needed product-specific
data regarding the pesticide after a determination of eligibility has been made. The Registrant
must review previous data submissions to ensure that they meet current EPA acceptance criteria
and if not, commit to conduct new studies. If a registrant believes that previously submitted data
meet current testing standards, then the study MRID numbers must be cited according to the
instructions in the Requirement Status and Registrants Response Form provided for each
product. The Agency intends to issue a separate product-specific data call-in (PDCI), outlining
specific data requirements.
2. Labeling for End-Use Products
In order to be eligible for reregi strati on, registrants must amend all product labels to
incorporate the risk mitigation measures outlined in Section IV. Tables 4 and 5 describe how
language on the labels should be amended.
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Labeling Changes Summary Table
In order to be eligible for reregistration, amend all product labels to incorporate the risk mitigation measures outlined in Section IV. The following table describes
how language on the labels should be amended.
Table 4: Summary of Labeling Changes for Dazomet Soil Uses
Description
Amended Labeling Language for Manufacturing Use Products
Placement on
Label
Manufacturing Use Products
For all Manufacturing
Use Products
"Only for formulation into a fumigant for the following use(s) [fill blank only with those uses that are being
supported by MP registrant]."
"Use in greenhouses is prohibited. Application with handheld equipment is prohibited. End use products
with directions for use for soil fumigation must specifically prohibit these uses and all references to such
applications must be removed."
"Dazomet cannot be formulated into end-use products labeled for pre-plant or pre-transplant uses unless the
registrant makes available to certified applicators who purchase or apply the end-use product a training
program that provides information on how to correctly apply the fumigant including how to protect
themselves, other handlers and bystanders, how to determine buffer zone distances, how to develop a
Fumigant Management Plan, and how to determine when weather and other site-specific factors are not
favorable for fumigant application. The training program must be made available to the certified applicators
at least annually and the registrant must be able to provide, upon request, the names, addresses, and certified
applicator license number of persons who successfully complete the training program.
"Dazomet cannot be formulated into end-use products labeled for pre-plant or pre-transplant uses unless the
registrant assures warning signs suitable for posting buffer zones are available to end-use product users at
the point of sale.
The buffer zone sign must meet the following standards:
o Signs must remain legible during entire posting period.
o The size and type of the buffer zone signs must follow the requirements in the Worker
Protection Standard for Agricultural Pesticides for treated area posting.
Directions for Use
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Contents of Sign
- "DO NOT ENTER/NO ENTRE,"
~ " [Name offiimigant] Fumigant BUFFER
ZONE,"
~ a space for the date and time of fumigation,
~ a space for the date and time buffer zone
restrictions are lifted (i.e., buffer zone period
expires)
~ brand name of this product, and
~ a space for the name, address, and telephone
number of the certified applicator in charge of
the fumigation
One of these
statements may be
added to a label to
allow reformulation of
the product for a
specific use or all
additional uses
supported by a
formulator or user
group
Directions for Use
"This product may be used to formulate products for specific use(s) not listed on the MP label if the
formulator, user group, or grower has complied with U.S. EPA submission requirements regarding support
of suchuse(s)."
"This product may be used to formulate products for any additional use(s) not listed on the MP label if the
formulator, user group, or grower has complied with U.S. EPA submission requirements regarding support
of suchuse(s)."
Environmental
Hazards Statements
Required by the RED
and Agency Label
Policies
"This product is toxic to fish and aquatic invertebrates. Do not discharge effluent containing this product
into lakes, streams, ponds, estuaries, oceans, or other waters unless in accordance with the requirements of a
National Pollution 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 the EPA."
Precautionary
Statements
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End Use Products Intended for Occupational Use
Restricted Use
Requirement for all
products that contain
soil use
"Restricted Use Pesticide due to acute inhalation toxicity to humans. For retail sale to and use by certified
applicators or persons under their direct supervision and only for those uses covered by the certified
applicator's certification."
Top of the front
panel
Certified applicator
must complete annual
training program
"The certified applicator supervising that application must successfully complete a dazomet training
program made available by the registrant within the last 12 months. The Fumigant Management Plan (see
details elsewhere on this label) must document when and where the training program was completed."
Directions for Use
Supervision of
handlers
"The certified applicator supervising the application must be at the fumigant application site and able to
maintain visual contact with every handler participating in the application starting when the fumigant is first
introduced into the soil and ending after the fumigant has stopped being delivered/dispensed to the soil and
the soil is sealed.
The certified applicator must provide fumigant safe handling information to each handler involved in the
application or confirm that each handler participating in the application has received fumigant safe handling
information in the past 12 months.
For all other fumigant handling tasks (as defined on this label), at least two WPS-trained handlers must be
present to monitor one another."
Directions for Use
Under the section
"protection for
handlers"
Fumigation Handlers
"Persons engaged in any of the following activities are defined as fumigant handlers:
Persons participating in the application as supervisors, loaders, drivers, tractor co-pilots, shovelers, or as
other direct application participants (application starts when the fumigant is first introduced into the soil
and ends after the fumigant has stopped being delivered/dispensed to the soil);
Persons taking air samples to monitor fumigant air concentrations;
Persons cleaning up product spills;
Persons handling or disposing of product containers;
Persons cleaning, handling, adjusting, or repairing the parts of fumigation equipment that may contain
product residues;
Persons installing, repairing, operating irrigation equipment in the fumigant application block or
surrounding buffer zone during the buffer zone period;
Persons entering the application site or surrounding buffer zone during the buffer zone period to
perform scouting or crop advising tasks;
In the
Precautionary Use
Section
79
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Persons installing, perforating (cutting, punching, slicing, poking), removing, repairing, or monitoring
tarps-until:
> After tarps are perforated and removed if tarp removal is completed less than 14 days after
application, or
> 14 days after application is complete if tarps are not perforated and removed during those 14 days, or
> 48 hours after tarps are perforated if they will not be removed prior to planting.
NOTE: see Tarp Perforation and Removal section on this labeling for requirements about when tarps are
allowed to be perforated."
Exclusion of Non
Handlers from
Application Block and
Buffer Zone
"The certified applicator supervising the application and the owner/operator of the establishment where the
fumigation is taking place must make sure that all persons who are not trained and PPE-equipped and who
are not performing one of the handling tasks defined in this labeling are:
excluded from application block during the entry prohibition period, and
excluded from the buffer zone during the buffer zone period."
Directions for Use
Under the section
"protection for
handlers"
Providing, cleaning,
and maintaining PPE
"The employer of the fumigant handlers must make sure that all handlers in the application block and the
surrounding buffer zone are provided and correctly wear the required PPE. The PPE must be cleaned and
maintained as required by the Worker Protection Standard for Agricultural Pesticides."
Directions for Use
Under the section
"protection for
handlers"
Respirator Availability
"In case of emergency or the need for immediate respiratory protection, the fumigation handler employer
must make sure that the following PPE are immediately available to all persons performing fumigant
handling activities:
unless an air-purifying respirator is being worn by each person performing a handling task at the
site, enough air-purifying respirators and face-sealing goggles (if the respirator is a half-face style)
of the type specified in the PPE section of this labeling must be immediately available at the site for
each handler."
Directions for Use
Under the section
"protection for
handlers"
PPE Requirements
Established by the
RED for dermal
protection
"Personal Protective Equipment (PPE) for skin protection
Some materials that are chemical-resistant to this product are" (registrant inserts correct chemical-resistant
material). "If you want more options, follow the instructions for category" [registrant inserts
A,B,C,D,E,F,G or H] "on an EPA chemical-resistance category selection chart."
Immediately
following/below
Precautionary
Statements:
Hazards to
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"All loaders, applicators and other handlers must wear at a minimum:
coveralls over short-sleeved shirt and short pants,
chemicals resistant gloves, and
shoes plus socks.
IMPORTANT: see Personal Protective Equipment (PPE) for eye and lung protection on this labeling for
more requirements."
iiiuic icqmicmciiia.
"Personal Protective Equipment (PPE) for eye and lung protection
All handlers required on this label to wear a respirator and eye protection must wear:
> a NIOSH-approved half-face, full-face, or helmet/hood style 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)., and
> face-sealing goggles if a half-face respirator is worn.
Handlers must wear the required respirator and eye protection when:
loading the fumigant, or
repairing equipment when exposure to liquid spray is possible, or
activating irrigation equipment when in the application block or surrounding buffer zone, or
repairing unperforated tarp within 14 days after the end of application, or
performing a handling task that is too short-term for air monitoring (described below) at hourly
intervals to be feasible, or
fumigant air monitoring (described below) indicates that a respirator and eye protection are
necessary.
Fumigant Air Monitoring: The following air monitoring procedures must be followed to determine whether
a respirator and eye protection are required for persons performing a fumigant handling task as defined in
this labeling.
Air monitoring samples for MITC must be collected in the breathing zone of a handler performing a
representative handling task starting approximately 30 minutes from the handler's initial exposure
and at least once every 1 hour thereafter.
A direct reading detection device, such as a Draeger device, with sensitivity of at least 100 ppb for
Humans and
Domestic Animals
PPE Requirements
Established by the
RED for all
Eye and Lung
Protection
Immediately
following/below
Precautionary
Statements:
Hazards to
Humans and
Domestic Animals
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MITC must be used to monitor air concentration levels of MITC.
If at any time (1) MITC concentrations are greater than or equal to 100 ppb, OR (2) any handler
experiences sensory irritation, then a respirator and eye protection as specified in this section must
be worn by every handler in the application block and surrounding buffer zone,
If two consecutive breathing zone samples taken at least 15 minutes apart, show levels have
decreased to less than 100 ppb for MITC, then handlers may remove the respirators and eye
protection.
If at any time (1) a handler experiences any sensory irritation when wearing a respirator, or (2) any
air sample is greater than or equal to 1000 ppb (1 ppm) for MITC, then all handler activities must
cease and handlers must be removed from the application block and surrounding buffer zone until
corrective action has been taken.
During the corrective actions a respirator and eye protection must be worn.
In order to resume work activities:
> Two consecutive air samples for MITC taken at the handling site at least 15 minutes apart must be
less than 1000 ppb (1 ppm) for MITC.
> During the collection of air samples a respirator and eye protection must be worn by the handler
taking air samples.
> If MITC concentrations are greater than or equal to 100 ppb, then handlers resuming their handler
activities must wear a respirator and eye protection.
See engineering controls section for more options."
Engineering Controls
"Engineering Controls for Motorized Ground Equipment with an Enclosed Cab:
Applicators using an enclosed cab that meets the definition in the Worker Protection Standard for
Agricultural Pesticides [40 CFR 170.240(d)(5)] may:
~ wear long-sleeve shirt, long pants, shoes, and socks;
~ if a respirator and eye protection are triggered by MITC air monitoring either wear the respirator and eye
protection required in the PPE section for respirator and eye protection or use an enclosed cab that is
declared in writing by the manufacturer or by a government agency to provide at least as much respiratory
protection as this type of respirator;
~ be provided, have immediately available for use, and wear in an emergency when they must exit the cab
in the application block or surrounding buffer zone: coveralls and chemical-resistant gloves plus - if not
already using one - the eye protection and respirator specified in the PPE section for respirator and eye
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protection
~ take off any PPE that was worn before reentering the cab, and
~ store all such PPE in a chemical-resistant container, such as a plastic bag, to prevent contamination of the
inside of the cab."
User Safety
Recommendations
"User Safety Recommendations
Users should wash hands before eating, drinking, chewing gum, using tobacco, or using the toilet.
Users should remove clothing/PPE immediately if pesticide gets inside. Then wash thoroughly and put on
clean clothing.
Users should remove PPE immediately after handling this product. As soon as possible, wash thoroughly
and change into clean clothing."
Precautionary
Statements under:
Hazards to
Humans and
Domestic Animals
immediately
following
Engineering
Controls
(Must be placed in
a box.)
User Safety
Requirements
"Follow manufacturer's instructions for cleaning/maintaining PPE. If no such instructions for washables
exist, use detergent and hot water. Keep and wash PPE separately from other laundry."
"Discard clothing and other absorbent materials that have been drenched or heavily contaminated with this
product's concentrate. Do not reuse them."
Precautionary
Statements:
Hazards to
Humans and
Domestic Animals
immediately
following the PPE
requirements
PPE Requirements
Established by the
RED1
For all
Formulations
"Respirator fit testing, medical qualification, and training
Employers must ensure that all fumigant handlers are:
Fit-tested and fit-checked using a program that conforms to OSHA's requirements (see 29CFR Part
1910.134)
Trained using a program that confirms to OSHA's requirements (see 29CFR Part 1910.134)
Examined by a qualified medical practitioner to ensure physical ability to safely wear the style of
respirator to be worn. A qualified medical practitioner is a physician or other licensed health care
Directions for Use
Under the section
"Protection for
Handlers"
83
-------
professional who will evaluate the ability of a worker to wear a respirator. The initial evaluation
consists of a questionnaire that asks about medical conditions (such as a heart condition) that would be
problematic for respirator use. If concerns are identified, then additional evaluations, such as a physical
exam, might be necessary. The initial evaluation must be done before respirator use begins. Handlers
must be reexamined by a qualified medical practitioner if their health statue or respirator style or use-
conditions change."
Application
Requirements, when
tarps are used: Tarp
Perforation and/or
/Removal
Note to Registrant:
Dazomet is not
typically used with a
tarp. However, if a
dazomet label contains
directions for use with
tarps, then all sections
of this label table that
pertain to tarps must
be added.
"Tarp Perforation and/or Removal
IMPORTANT: Persons perforating, repairing, removing, and/or monitoring tarps are defined, within certain
time limitations, as fumigant handlers (see definition of fumigant handlers in this labeling) and must be
provided the PPE and other protections for handlers as required on this labeling and in the Worker
Protection Standard for Agricultural Pesticides.
Tarps used for fumigations must be perforated (cut, punched, poked, or sliced) only by mechanical methods.
Perforation by hand or with hand-held tools is prohibited.
Each tarp panel used for broadcast fumigation must be perforated using a lengthwise cut.
Tarps cannot be perforated until a minimum of 5 days (120 hours) have elapsed after the fumigant injection
into the soil is complete (e.g. after injection of the fumigant product and tarps ~ if used ~ have been laid or
after drip lines have been purged and tarps have been laid), unless an adverse weather condition exists for
broadcast applications. See below.
If tarps will be removed after perforation, tarp removal cannot begin until at least 24 hours after tarp
perforation is complete.
If tarps will NOT be removed after perforation, planting or transplanting cannot begin until at least 48 hours
after the tarp perforation is complete
If tarps are left intact for a minimum of 14 days after fumigant injection into the soil is complete, planting or
transplanting can take place while the tarps are being perforated.
Adverse Weather Conditions Exception for broadcast applications only:
Direction For Use
84
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Tarps may be removed before the required 5 days (120 hours) if adverse conditions will compromise the
integrity of the tarp, provided that:
At least 48 hours have passed after the fumigant injection into the soil is complete,
The buffer zone period is extended until 24 hours after tarp removal is complete,
Subsequent fumigations of untreated areas within the application block do not occur for at least 24-
hours after tarp removal is complete, and
Appropriate PPE, respiratory protection, air monitoring and other requirements for the protection of
handlers are met.
Monitoring Air
Concentration Levels
"MONITORING AIR CONCENTRATION LEVELS
Monitoring Air Concentrations in the Buffer Zone Areas: When air concentration levels must be
monitored (i.e., as specified in the general buffer zone requirements section), use a direct reading detection
device, such as a Draeger device, with a sensitivity of at least 100 ppb for MITC (a breakdown product of
dazomet)."
Directions for Use
under the heading
"General Buffer
Zone
Requirements"
Agriculture Use
Requirements box
"Agricultural Use Requirements
After the standard paragraphs for the Agricultural Use Requirements box, substituted the following text for
the standard restricted-entry interval and double notification requirements:
"For entry prohibition and notification requirements, see the "Application Block Entry Prohibition and
Notification" section of this labeling."
Agricultural Use
Requirements box
Application Block
Entry Prohibitions
"Entry Prohibitions
Entry (including early entry that would otherwise be permitted under the WPS) by any person - other than a
correctly trained and PPE-equipped handler who is performing a handling task listed on this labeling - is
PROHIBITED -from the start of the application until:
> 5 days (120 hours) after application is complete if tarps are not perforated and removed for at least
14 days following application, or
> 5 days (120 hours) after application has ended for untarped applications., or
Directions for Use
under the heading
"heading
"Application
Block Entry
Prohibition and
Notification"
85
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> 48 hours after tarps are perforated if they will not be removed within 14 days following application,
or
> tarp removal is completed if tarps are both perforated and removed less than 14 days after
application.
NOTE: see Tarp Perforation and Removal section on this labeling for requirements about when tarps are
allowed to be perforated."
Application Block
Notification
Requirement
"NOTIFICATION: Notify workers of the application by warning them orally and by posting fumigant
warning signs. The signs must bear the skill and crossbones symbol and state:
- "DANGER/PELIGRO,"
- "Area under fumigation, DO NOT ENTER/NO ENTRE,"
~ "[Name of fumigant] Fumigant in USE,"
~ the date and time of fumigation,
~ the date and time entry prohibition period is over,
~ Name of this product, and
~ name, address, and telephone number of the certified applicator in charge of the fumigation.
Post the fumigant warning sign instead of the WPS sign for this application but follow all WPS
requirements pertaining to location, legibility, size, and timing of posting and removal.
Post the fumigant warning signs at all entrances to the application block.(i.e., the field or portion of a field
treated with a fumigant in any 24-hour period)"
Direction for Use
under the heading
"Application
Block Entry
Prohibition and
Notification"
Mandatory Good
Agricultural Practices
for all
formulations
"Mandatory Good Agricultural Practices (GAPs)
The following GAPs must be followed during all fumigant applications. All measurements and other
documentation planned to ensure that the mandatory GAPs are achieved must be recorded in the FMP
and/or the post application summary report.
Weather Conditions
Prior to fumigation the weather forecast for the day of the application and the 48-hour period following
the fumigant application must be checked.
Do not apply fumigant if ground-level winds are less than 2 mph.
Applications must not occur during a temperature inversion or when temperature inversions are
Directions for Use
under "Mandatory
Good Agricultural
Practices"
86
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forecasted to persist for more than 6 consecutive hours for the 36-hour period after application.
o The application must not occur if the following visual features exist at the time of the
application, misty conditions (for day or night applications) or clear skies where stars are
visible (for nighttime applications).
Detailed local forecasts for sky conditions, weather conditions, wind speed, and forecasted temperature
inversions may be obtained on-line at ://www.nws. noaa.gov.
For further guidance, contact the local National Weather Service Forecasting Office."
The following requirements may already be on dazomet end use product labels. All of these label
statements are required:
"Do not use dazomet when the soil temperature is extremely high (over 90 deg F, 2"deep).
Do not apply within 3-4 feet of growing plants or closer than the drop line of trees and large shrubs.
If slopes are treated with this product, take precautions to prevent the chemical from washing
downward to growing plants.
The area intended for treatment should be in seedbed condition with a fine tilth, free of clods. Do
not apply dazomet to dry or improperly tilled soil. Repeated cultivation before treating will
improve control of perennial weeds. Ditching around the site will prevent weed seeds, nematodes,
and fungi from washing into the treated area and contaminating it.
For optimal effect, the soil to be fumigated must have sufficient moisture for good plant growth (at
least 50% field capacity) for 5-14 days (depending on temperature) before the treatment.
Do not apply dazomet if ambient air temperature exceeds 103 degrees F. (I'm not sure if this is for
efficacy or risk?)
After application, the soil must be kept uniformly moist for 5-7 days. As soon as possible after
incorporation, the soil should be sealed to retain the concentration of gases in the soil which can be
achieved by:
o Compacting the soil surface after incorporation with a roller attached behind the compacting
implement.
o Moistening the surface after incorporation so a crust forms.
o Lightly moistening the soil on the third and fourth days after treatment in case the weather dries
out the soil surface to avoid surface cracks.
o In difficult situations best results may be obtained by tarping the treated area.
Do not store dazomet in an open spreader overnight.
Do not apply dazomet when wind may cause granules to drift from target area.
87
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Do not apply dazomet through any type of irrigation equipment.
Before using dazomet be aware that the three most critical factors for a successful fumigation
program are: soil preparation, soil temperature, and soil moisture."
Site-Specific
Fumigation
Management Plans for
all dazomet end-use
products containing
directions for use for
soil fumigation
"Site-Specific Fumigation Management Plan (FMP)
Prior to the start of fumigation, the certified applicator supervising the application must verify that a site-
specific fumigation management plan (FMP) exists for each application block (i.e., a greenhouse or field or
portion of a field treated with a fumigant in any 24-hour period). The FMP may be prepared by the certified
applicator, the site owner/operator, registrant, or other party. The certified applicator must verify in writing
the site-specific FMPs reflects current site conditions before the start of fumigation.
Each site specific FMP must contain the following elements:
*J* General site information
> Site address,
> Site operator/owner's name, address, and, phone number
> Map, aerial photo, or detailed sketch showing field location, dimensions, buffer zones, property
lines, public roads, bus stops, water bodies, wells, rights-of-ways inside buffers, nearby application
blocks, surrounding structures (occupied and non-occupied), locations of posted signs for buffers,
and sites requiring % mile buffer zones (e.g., prisons, schools, hospitals, state licensed day care
centers) with distances from the application site labeled
*J* Applicator information (license #, address, phone, contact information for person supervising the
fumigation)
*J* Authorized on-site personnel (Names of all handlers and the tasks they are authorized and trained to
perform)
* Application procedures
> Fumigation window (target application date, earliest and latest possible date of fumigation, duration
of fumigation)
> Product information (brand name, registration number)
> Type of fumigation (e.g., shank, broadcast, drip, raised bed, strip, etc.)
> Target application rate and application block size
* Good Agricultural Practices (GAPs)
> Description of applicable mandatory GAPs (registrants may also include optional GAPs)
> Measurements and other documentation planned to ensure GAPs are achieved (e.g. measurement of
soil and other site conditions; tarp repair/cutting/removal plans; etc.)
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading "Site-
Specific
Fumigation
Management Plan
(FMP)"
88
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Buffer zones
> Calculations and rationale for buffer zones distances (e.g. specify table from label that distances
based on, rate and block size, applicable credits applied)
> Start and stop times for buffer zones
Respirators and other personal protective equipment (PPE) for handlers (respirator type, respirator
cartridge, and other PPE selection; verification that respirator training/fit-testing/medical exams is
current; and maintenance/storage procedures)
Air monitoring
> Type of samples that will be collected (e.g., occupational, in occupied structures, outside buffer
zone if fumigation site monitoring is conducted, etc.)
> When and where samples will be collected
> Duration of samples
> Sampling methods
> Name, address, and, phone number of person taking samples
Posting (names of persons who will post signs, location of posting signs, procedures for posting and
sign removal)
Site specific response and management
> Fumigation site monitoring
Description of who, when, where, and procedures for monitoring buffer zone perimeter
> Response information for neighbors
List of residences and businesses informed (neighboring property owners)
Method of sharing information
State and tribal lead agency notification
> Include information that is sent to the lead agency
Plan describing how communication will take place between applicator, land owner/operator, and other
on-site handlers (tarp cutters/removers, irrigators, etc.)
Record keeping procedures
Emergency procedures (evacuation routes, locations of telephones, contact information for first
responders, local/state/federal contacts, key personnel and emergency procedures/responsibilities in
case of an incident, equipment/tarp/seal failure, odor complaints or elevated air concentration levels
outside buffer zone suggesting potential problems, or other emergencies).
Hazard communication (product labels, material safety data sheets, etc.)
For situations where an initial FMP is developed and certain elements do not change for multiple fumigation
89
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sites (e.g. applicator information, authorized on-site personnel, record keeping procedures, emergency
procedures, etc.) only elements that have changed need to be updated in the site-specific FMP provided the
following:
The certified applicator supervising the application has verified that those elements are current and
applicable to the application block before it is fumigated and has documented the verification in the
site-specific FMP.
Recordkeeping requirements are followed for the entire FMP (including elements that do not
change)
Once the application begins, the certified applicator and owner/operator of the application block must
provide a copy of the FMP to handlers who are involved in the fumigation, workers in adjacent areas to the
application block, and Federal/State/local enforcement personnel, upon request.
The certified applicator supervising the fumigation and the owner/operator of the agricultural establishment
where the fumigation is taking place must, upon request, make the FMP available to any Federal, state,
tribal, or local enforcement personnel.
Within 30 days of completing the application portion of the fumigation process, the certified applicator
supervising the application must complete a post fumigation application summary that describes any
deviations from FMP that have occurred, measurements taken to comply with GAPs as well as any
complaints and/or incidents that have been reported to him/her. The summary must include the actual date
of the application, application rate, and size of application block fumigated.
The certified applicator who supervised the fumigation and the owner/operator of the agricultural
establishment where the fumigation took place must keep a signed copy of the site-specific FMPs and the
post-application summary record for at least 2 years following the application and must make them
available, upon request, to Federal, state, tribal, and/or local enforcement personnel."
Information Exchange
"When the certified applicator supervising the application leaves the application site after the application
portion of the fumigation process is complete and other persons will be performing handler tasks (see the
handling activities listed elsewhere in this labeling), the certified applicator must communicate in writing all
of the requirements on this labeling with respect to the fumigation process and protection of handlers to the
owner/operator of the agricultural establishment where the fumigation is taking place.
90
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IMPORTANT: this requirement does not override the requirements in the Worker Protection Standard for
Agricultural Pesticides for information exchange between owners/operators of agricultural establishments
and commercial pesticide applicators."
General Buffer Zones
requirements for all
formulations
"General Buffer Zone Requirements
A "buffer zone" must be established for every fumigant application
"Buffer zone" is an area established around the perimeter of each application block where a soil
fumigant is applied. The buffer zone must extend from the edge of the application block equally in all
directions.
All non-handlers including field workers, nearby residents, pedestrians, and other bystanders, must be
excluded from the buffer zone during the entire buffer zone period except for certain exemptions for
persons transiting through the buffer zone (see transit exemptions below).
An "application block" is a greenhouse or field or portion of a field treated with a fumigant in any 24-
hour period.
The "buffer zone period" starts when the fumigant is first introduced into the soil within the application
block and lasts for a minimum of 48 hrs after injection of the fumigant product has stopped and tarps
have been laid, and after any the hot gas drip lines have purged of fumigant.
"Roadway" means that portion of a street or highway improved, designed, or ordinarily used for
vehicular travel. "Roadway" does not include any sidewalk or shoulder even if the sidewalk or shoulder
is used by persons riding bicycles. In the event a highway includes two or more separated roadways, the
term "roadway" shall refer to any such roadway separately.
Buffer zone distances
Minimum buffer zone distances must be based on look-up tables in the "Buffer Zone Distance" section
of this label (25 feet is smallest buffer zone distance regardless of site-specific application parameters).
Authorized entry to buffer zones
Only trained and PPE-equipped handlers performing a fumigant handling tasks listed in this labeling are
allowed in the buffer zone during the buffer zone period. All non-handlers including field workers,
nearby residents, pedestrians, and other bystanders, must be excluded from the buffer zone during the
buffer zone period except for certain persons in transit (see exemptions section).
Buffer zone proximity
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading
"General Buffer
Zone
Requirements"
91
-------
Buffer zones from multiple application blocks may not overlap (including blocks fumigated by adjacent
property owners, (see below for exemptions for areas not under the control of owner/operator of
application block).
No fumigant applications will be permitted within 0.25 (one-quarter) mile of schools, state licensed
daycare centers or preschools, nursing homes, assisted living facilities, elder care facilities, hospitals, in-
patient clinics and prisons if these facilities will be occupied during the buffer zone period.
Exemptions for transit within buffer zones ( Posting and site specific response and management
requirements in this labeling must be complied with.)
Vehicular and bicycle traffic on public and private roadways within the buffer zone is permitted.
Bus stops or other locations where persons wait for public transit are not permitted with in the buffer
zone.
Structures under the control of owner/operator of the application block ( Posting and site specific
response and management requirements in this labeling must be complied with.)
Buffer zones may not include buildings used for storage such as sheds, barns, garages, etc., UNLESS,
1. The storage buildings are not occupied during the buffer zone period, and
2. The storage buildings do not share a common wall with an occupied structure.
Areas not under the control of owner/operator of the application block (Posting and site specific
response and management requirements in this labeling must be complied with).
Buffer zones may not include residential areas (including employee housing, private property,
buildings, commercial, industrial, and other areas that people may occupy or outdoor residential areas,
such as lawns, gardens, or play areas, UNLESS,
1. The occupants provide written agreement that they will voluntarily vacate the buffer zone during the
entire buffer zone period, and
2. Reentry by occupants and other non-handlers must not occur until
The buffer zone period has ended, and
Two consecutive air samples for MITC taken in the structure at least 30 minutes apart must
indicate less than 100 ppb MITC is present.
Buffer zones may not include agricultural areas owned/operated by persons other than the
owner/operator of the application block, UNLESS,
1. The owner/operator can ensure that the buffer zone will not overlap with a buffer zone from any
adjacent property owners, and
92
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2. The owner/operator of the areas that are not under their control provides written agreement to the
certified applicator supervising the fumigant application that they, their employees, and other
persons under their jurisdiction will not enter or remain in the buffer zone during the entire buffer
zone period.
Buffer zones may not include publicly owned and/or operated areas (e.g., parks, rights-of-way,
sidewalks, walking paths, playgrounds, athletic fields, etc), UNLESS,
1. The area is not occupied during the entire buffer zone period,
2. Entry by any person, except a trained and PPE-equipped handler performing a handling task listing
in this labeling, is prohibited during the buffer zone period, and
Written permission to include the public area in the buffer zone is granted by the appropriate state
and/or local authorities responsible for management and operation of the area."
Buffer Zone Distances
for all formulations
"Buffer Zone Distances
Buffer zone distances must be calculated using the application rate and the size of the application block.
Figure 1. Broadcast Application
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading "
Buffer Zone
Distances"
Figure 2. Bedded Application
In Figures 1 and 2, the dashed line represents the perimeter of the field, the shaded area is the portion of the
field that is treated, and the un-shaded area is the area of the field that is untreated. Assuming both fields
are 10 acres, and only 50% of field in figure 2 is fumigated, the labeled rate per treated acre is 400 Ibs ai/A
for both Figure 1 and 2. The broadcast rate for figure 1 is 400 Ib ai/A but the effective broadcast equivalent
rate for Figure 2 is 200 Ibs ai/A. The minimum buffer zone distances must be based on the broadcast or
effective broadcast equivalent rates."
Note to registrant: Labels may express rates as Ibs per treated acre under the application instructions but they must
identify buffer zone distances based on the broadcast or effective broadcast equivalent rates.
93
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Buffer Zone Credits
ii
d
For all dazomet soil applications, the following tables must be used to determine the minimum buffer
istances. Round-up to the nearest rate and block size, where applicable."
Buffer zone distances (in feet) for all dazomet soil applications
Stock
Size
(acies)
1 or less
2
5
10
15
20
30
40
Btodc
Sne
(acres)
1 or less
2
5
10
15
20
30
40
Application Rates for either surface or incorporated applications (Ibs ai/acre)
530
200
200
200
350
500
650
812
1080
400
75
100
150
239
329
440
599
770
390
72
9fi
14?
233
318
426
582
750
380
69
92
144
22fi
308
412
565
730
370
66
88
141
219
298
398
548
710
360
63
84
138
213
287
384
531
690
350
60
80
135
207
278
370
514
670
340
57
76
132
201
269
356
496
650
330
54
72
128
194
259
343
480
630
320
51
68
124
187
250
330
460
610
310
48
64
120
179
237
317
44fi
590
300
45
60
lie
172
227
305
430
565
290
42
56
112
164
216
288
411
545
280
39
52
108
158
208
275
400
524
270
36
48
104
156
208
260
383
505
265
33
44
100
152
204
250
369
500
260
30
40
89
141
193
245
360
490
250
25
36
78
130
182
234
345
471
240
25
32
67
119
170
223
330
452
Application Ratesfor either surface or incorporated applications (Ibs ai/acre)
230
25
28
56
IBS
IfiO
212
323
433
220
25
25
46
18
MS
201
308
414
210
25
25
36
87
139
WO
293
395
200
25
25
25
19
133
18?
281
375
190
25
25
25
76
128
179
268
357
180
25
25
25
74
122
171
255
339
170
25
25
25
71
117
163
242
321
160
25
25
25
18
111
154
229
303
150
25
25
25
65
105
145
215
285
140
25
25
25
62
99
136
212
267
132
25
25
25
58
92
125
188
250
130
25
25
25
58
92
125
188
250
120
25
25
25
53
82
110
164
218
110
25
25
25
41
72
95
141
186
100
25
25
25
43
62
80
117
154
90
25
25
25
38
52
65
94
122
80
25
25
25
33
42
50
70
90
70
25
25
25
28
32
35
47
58
66
25
25
25
25
25
25
25
25
n
"Buffer Zone Credits
The buffer zone distances for dazomet applications may be reduced by the percentages listed below. Credits
may be added, to a total of 20%. Also the minimum buffer zone distance is 25 feet regardless of buffer zone
credits available.
10% reduction in buffer zone distance, IF the organic content of soil in the application block is greater
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading
"Buffer Zone
94
-------
than 3%. Record the measurements taken to verify the organic content in the FMP.
10% reduction in buffer zone distance, IF the clay content of the soil in the application block is greater
than 27%. Record the measurements taken to verify the clay content in the FMP.
Example of credit calculation
For example, if the buffer zone is 50 feet and the application qualifies for a buffer zone reduction credit
since the soil organic content is greater than 3%. Then the buffer zone can be reduced by 10%, i.e., reduced
by 5 feet based on the following calculation: 50 feet - (50 feet x 10%) = 45 feet"
Credits"
Posting of Buffer
Zones
"Posting Fumigant Buffer Zones
Posting all entrances to the application block (i.e., the greenhouse or field or portion of a field treated
with a fumigant in any 24-hour period) is required for all soil fumigants and use sites. The posting
requirements for the application block are listed elsewhere in this labeling.
Posting of the fumigation buffer zone is required, except when one of the following conditions exist:
(1) if there is a physical barrier that prevents access into the buffer zone, such as a fence or wall, that
separates the edge of the buffer zone from workers or bystanders, or
(2) if the area within 300 feet of the edge of the buffer zone is entirely controlled by owner/operator of
the application block (i.e., the greenhouse or field or portion of a field treated with a fumigant in
any 24-hour period); however this exception does not apply to any area under the control of the
owner/operator that may be used as housing for workers or other employees. IMPORTANT: if
there is public land or any land under someone else's control within 300 feet from the edge of the
buffer zone, the buffer zone must be posted.
If the buffer zone must be posted, signs must be placed at all usual points of entry and along likely
routes of approach from areas where people not under the control of the application block's
owner/operator may approach the buffer zone.
o Some examples of points of entry include, but are not limited to, roadways, sidewalks, paths,
and bike trails.
o When there are no usual points of entry, signs must be posted in the corners of the buffer zone,
between the corners of the buffer zone, and along sides so that one sign can be viewed (not
read) from the previous one.
o The buffer zone posting signs must remain posted at least until the end of the buffer zone period
and must be removed within 3 days after the end of the buffer zone period.
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading
"Posting"
95
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Site specific response
Contiguous Application Blocks Exception: If multiple contiguous application blocks are fumigated
within a 14-day period, a buffer zone may be established starting from the outer edge of the contiguous
application blocks. This buffer zone is in effect from the beginning of the first application until the
buffer zone period for the last application block has expired. The periphery of the buffer zone must be
posted during this entire period. Signs may remain posted until Sdays after the buffer zone period for
the last application block has expired.
The buffer zone posting should meet the following standards:
o The printed side of the sign must face away from the buffer zone.
o Signs must remain legible during entire posting period.
o The signs at entrances to buffer zones must be removed by the certified applicator in charge of
the fumigation (or someone under his/her supervision).
o The general standards for size and type of signs for the buffer zone signs must follow the
requirements in the Worker Protection Standard for Agricultural Pesticides for treated area
posting.
o The signs must remain visible and legible during the time they are posted."
Contents of Signs
The treated area sign must state the following: The buffer zone sign must state the following:
~ Skull and crossbones symbol ~ Do not walk sign
* (5)
- DANCJEWPELKJKU, ,ID() NQT ENTER/NO ENTRE,"
E^OE^' °° N°T * '-»* Fum1^ BUFFER
- " [Name offumigant} Fumigant in USE," __ ^ ^ ^ ^ Qf &mi ^
- the date and time of fumigation, .. ^ dat£ ^ ^ buffer zon£ restrictlons are
- the date and time entry prohibition is lifted ^ (i buffer zon£ nod ireg)
- brand name of this product, and .. brand nam£ Qf ^ ^ and
- name address, and telephone number of the .. ^^ ^^ ^ tel hone number of the
certified applicator in charge of the fumigation. certified appllcator m charge of the &migatlon
"Site Specific Response and Management
In the Directions
96
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and management
The certified applicator must either follow the directions under the "fumigant site monitoring" section or
follow the directions under the "response information for neighbors" section.
Fumigation Site Monitoring
From the beginning of the fumigant application until the buffer zone period expires, a certified applicator or
someone under his/her supervision must monitor the air concentration levels of the fumigant in the area
between the buffer zone and any residences or businesses that trigger the 'response information for
neighbors' requirement.
The person monitoring the air concentration levels must take readings starting approximately 30
minutes from the start of application and at least once each hour during the entire application and buffer
zone period.
A direct reading detection device, such as a Draeger device with a sensitivity of at least 100 ppb for
MITC must be used to monitor the air concentration levels of MITC.
If at any time (1) MITC concentrations are greater than or equal to 100 ppb OR (2) the person
monitoring the air concentrations experiences sensory irritation, then the emergency response plan
stated in the FMP must be immediately implemented by the person monitoring the air concentrations
If other problems occur, such as a tarp coming loose, then the appropriate control plan must be
activated.
The results of the air concentration monitoring must be recorded in the FMP.
Informing the appropriate federal, state or tribal lead agencies is still required.
Response Information for Neighbors
The certified applicator (or someone under his/her supervision) supervising the fumigation must ensure that
residences and owners/operators of businesses that meet the criteria below have been provided the
emergency response information at least 48 hours before fumigation occurs. The information provided may
include application dates that range for no more than 2 weeks. After 2 weeks, the information must be
delivered again.
Criteria for providing response information for neighbors:
If the buffer zone is less than or equal to 100 feet, then residences and businesses within 50 feet from
the edge of the buffer zone must be informed.
for Use for Pre-
plant soil
fumigation under
the heading "Site
specific response
and management"
97
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If the buffer zone is greater than 100 feet but less than or equal to 200 feet, then residences and
businesses within 100 feet from the edge of the buffer zone must be informed.
If the buffer zone is greater than 200 feet but less than or equal to 300 feet, then residences and
businesses within 200 feet from the edge of the buffer zone must be informed.
If the buffer zone is greater than 300 feet, then residences and businesses within 300 feet from the edge
of the buffer zone must be informed.
Information that must be included:
Location of the application block and surrounding buffer zone
Fumigant(s) applied including EPA Registration #
Applicator and property owner/operator contact information
Time period that fumigation may occur (must not range more than 2 weeks)
Duration of buffer zone
The information must also include:
o information on what is being applied,
o signs and symptoms of exposure to the fumigant,
o what to do and who to call if you believe you are being exposed (911 in most cases).
The method used to share the response information for neighbors must be described in the FMP and
may be accomplished through mail, door hangers, or through other methods that will effectively inform
people in residences and businesses within the required distance from the edge of the buffer zone."
Notice to State and
Tribal Lead Agencies
"Notice to State and Tribal Lead Agencies
The state and trial lead agency information must be provided to the appropriate state or tribal lead agency in
a written format prior to the application.
The information that must be provided to state and trial lead agencies includes the following:
o Location of the application block and surrounding buffer zone,
o Fumigant(s) applied including EPA Registration #,
o Applicator and property owner/operator contact information,
o Time period that fumigation may occur (must not range more than 2 weeks),
Directions for Use
under "Notice to
State and Tribal
Lead Agencies"
98
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o Duration of buffer zone."
Pre-plant Application
Restrictions
Maximum incorporated rate for all uses, except for golf course renovation, is 425 Ibs ai/A.
The maximum rate for golf course renovation, with the incorporated application method is 530 Ibs ai/A
"Use in greenhouses is prohibited."
"Application with handheld equipment is prohibited."
In the Directions
for Use for Pre-
plant soil
fumigation under
the heading
"Maximum
Application Rates
for Pre-Plant Soil
Fumigation"
within its own box
Environmental
Hazards
"This pesticide is toxic to fish and aquatic invertebrates. Do not apply directly to water, or to areas where
surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water
when disposing of equipment washwaters or rinsate."
Precautionary
Statements
immediately
following the User
Safety
Recommendations
Surface and Ground
Water Advisory
"While dazomet and its major degradate MITC have certain properties and characteristics in common with
chemicals that have been detected in groundwater (MITC is highly soluble in water and has low adsorption
to soil), volatilization is this chemical's most important route of dissipation.
To reduce the potential for leaching to groundwater, especially in soils with shallow groundwater, for
broadcast, tarped applications, the tarps must be perforated (cut, punched, etc.) before noon and only when
rainfall is not expected within 12 hours.
For raised-bed, tarped applications, rainfall is not a factor since planting occurs with the tarp in place.
For untarped applications of dazomet, potential leaching into groundwater and runoff into surface water
can be reduced by avoiding applications when heavy rainfall is forecasted to occur within 24 hours."
Precautionary
Statements
immediately
following the User
Safety
Recommendations
General Application
Restrictions
"Do not apply this product in a way that will contact workers or other persons, either directly or through
drift. Only protected handlers may be in the area during application."
Place in the
Direction for Use
99
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directly above the
Agricultural Use
Box.
1 PPE that is established on the basis of Acute Toxicity of the end-use product must be compared to the active ingredient PPE in this document. The more
protective PPE must be placed in the product labeling. For guidance on which PPE is considered more protective, see PR Notice 93-7.
100
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The label changes required for dazomet products with antimicrobial uses are listed below in
Table 5.
Table 5: Labeling Changes Summary Table for the Antimicrobial Uses of Dazomet
Description
Amended Labeling Language
Placement on Label
For remedial
treatment of
wooden
poles/timbers
Add language clarifying application methods
1. Plug the pre-drilled holes immediately after
applications;
2. Do not treat structures/beams indoors;
3. Do not drill an application hole through
seasoning checks to apply product. If the hole
intersects a check, plug the hole and drill
another. If more than 2 treatment holes
intersect an internal void or rot pocket, re-drill
the holes farther up the pole into relatively
solid wood.
Directions for Use
Additional label
language for
registrations that
use dazomet as a
materials
preservative or in
industrial
processes and
water systems
"This pesticide is toxic to fish and aquatic
invertebrates."
Environmental Hazards
Additional Label
Language for all
oil field uses
"This pesticide is toxic to fish, aquatic invertebrates,
oysters, and shrimp."
Environmental Hazards
For wood
preservation uses,
the label must
state
Environmental Hazards
"This pesticide is toxic to fish and aquatic
invertebrates"; and
"This pesticide is expected to be toxic when in contact
with terrestrial or aquatic plants."
For all scenarios
that use metering
pumps:
"Gloves must be worn when handling the product."
Personal Protective
Equipment (PPE)
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Additional PPE
language for the
cooling water
system use
"Appropriate PPE (long pants, long-sleeved shirts,
chemical resistant gloves, and goggles or face shield)
must be used when applying the product."
Personal Protective
Equipment (PPE)
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Appendix A
Appendix A(l): Dazomet (PC Code 035602) Soil Fumigant Uses Eligible for Reregistration
Use Site
Formulation
Method of
Application
Maximum Application Rate
Use Limitations
Soil
Nonbearing crops (such as
orchard crops, berries, and
flower bulbs), ornamental
sites (establishing or
renovating), field nurseries
(establishing or renovating),
compost piles, potting soils,
and strawberries and
tomatoes in California only
Golf greens/tees, turf sites
(establishing or renovating),
Granular
Granular
Tractor drawn
spreader
Tractor drawn
spreader
425 Ibs ai/A for incorporated
applications.
265 Ibs ai/A for surface
applications.
530 Ibs ai/A for incorporated
applications.
265 Ibs ai/A for surface
applications.
Application with hand-held applications is
prohibited.
Labels must prohibit use in greenhouses.
See the label table in Section V for additional use
restrictions.
Application with hand-held applications is
prohibited.
Labels must prohibit use in greenhouses.
See the label table in Section V for additional use
restrictions.
Appendix A(2): Dazomet (PC Code 035602) Antimicrobial Uses Eligible for Reregistration
Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
Materials Preservatives
Clay slurries, adhesives,
coatings and high viscosity
suspensions
Ready to use
1448-103
1448-395
1706-193
Pump or Gravity
feed.
Add 0.03-0.50% by weight
based on the total
formulation. Actual use
levels should be determined
by a test of the system.
Product should be added at a point in the system
where there will be sufficient time and agitation
for good mixing and dispersion.
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Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
9386-3
9386-28
Formulation
Intermediate:
1448-98
Technical
chemical:
9386-10
Soluble
concentrate
1448-104
1706-195
9386-13
33753-25
Pump or Gravity
feed.
Add 0.01-0.11% by weight
based on the total
formulation. Actual use
levels should be determined
by a test of the system.
Product should be added at a point in the system
where there will be sufficient time and agitation
for good mixing and dispersion.
Flowable
concentrate
67869-25
Pump or Gravity
feed.
Add 0.5-2.5% by weight of
the suspension or dispersion.
Actual use levels should be
determined by a test of the
system.
Product should be added at a point in the system
where there will be sufficient time and agitation
for good mixing and dispersion.
Ready to use
74655-1
Pump or Gravity
feed.
Add 1.67-2.5 pounds per
1000 gallons of material to be
preserved. Actual use levels
should be determined by a
test of the system.
Product should be added at a point in the system
where there will be sufficient time and agitation
for good mixing and dispersion.
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Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
Paper and pulp mill Slime
control
Ready to use
1448-103
1448-395
9386-3
9386-28
Pump or Gravity
feed.
Intermittent method: Add 12-
20 oz per ton (dry basis) of
pulp or paper for two hours
every 8 hours.
Badly fouled systems may require cleaning before
initial treatment.
Continuous method: Add 5-
15 oz per ton (dry basis) of
pulp or paper on a continuous
basis.
Ready to use
1706-193
Pump or Gravity
feed.
Add 5-36 oz per ton of
finished product on a
continuous basis. Actual use
levels should be determined
by a test of the system.
Shock dosages are to be avoided. Badly fouled
systems may require cleaning before initial
treatment.
Ready to use
1706-195
Pump or Gravity
feed.
0.083-0.415 Ibs. per 1000
gallons of treated water.
Actual use levels should be
determined by a test of the
system.
Flowable
concentrate
67869-25
Pump or Gravity
feed.
Add 0.5-2.5% by weight of
the suspension or dispersion.
Actual use levels should be
determined by a test of the
system.
Badly fouled systems may require cleaning before
initial treatment.
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Use Site
Leather tanning
Metal working fluids and
lubricants
Construction Products:
Caulking material, Concrete
additives, concrete and
Formulation
Ready to use
74655-1
Soluble
concentrate:
67869-46
Soluble
concentrate:
67869-46
Soluble
concentrate:
67869-46
Method of
Application
Pump or Gravity
feed.
Immersion
Incorporation
Incorporation
Application Rate/ No. of
applications
If system is noticeably fouled,
add product at the rate of 0.5
to 3.0 pounds per ton of pulp
or paper product. Additions to
additive system should be
made directly at the rate of
0.2 to 4.0 pounds (24 to
480ppm) per 1000 gallons.
Add product at the rate of
0.5-2.0 pounds per ton of
pulp or paper produced. Treat
the system as needed to
maintain control. Additions
to the additive system may be
reduced to 0.2 to 2.0 pounds
(24 to 240 ppm) per 1000
gallons.
Apply directly at a
concentration of 1000 to
SOOOppm into pickle solution
Apply directly at a
concentration of 1000 to
10,000 ppm, can be added or
metered into the final cutting
fluid either prior to its
addition to the system or after
the system has been filled
Can be fed at concentration of
250 to 6000 ppm either
directly to the finished
Use Limitations
Badly fouled systems may require cleaning before
initial treatment.
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Use Site
masonry additives
Paints/coatings/inks/dyes
Polymer
dispersion/emulsions
Formulation
Soluble
concentrate:
67869-46
Soluble
concentrate:
67869-46
Method of
Application
Incorporation
Incorporation
Application Rate/ No. of
applications
product or to one of the raw
materials
Add at concentrations of 250
to 4000 ppm into the makeup
water during the grind during
the manufacturing process
Add using moderate agitation
immediately following the
cool down process at
concentrations of 250 to 4000
ppm
Use Limitations
Industrial Processes and Water Systems
Recirculating cooling water
systems
Ready to use
1448-103
1448-395
9386-3
9386-28
Soluble
concentrate
1448-104
Pump or Gravity
feed.
Pump or Gravity
feed.
Add 3.25-6.5 ounces of
product to 1000 gallons of
water to produce a 30-60ppm
concentration initially. Add
0.5-3.25 ounces of product to
1000 gallons of water to
produce a 5-30ppm
concentration to maintain
control.
Add 16 ounces of product per
each 5,000-16,000 gallons of
water in system initially to
produce a concentration of
7.5-15ppm. Add 16 ounces
of product per each 15,000-
96,000 gallons of water in
system to produce a
concentration of 1.25-7. 5ppm
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Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
to maintain control.
Crystalline
9386-13
Open pour
Add 9.5 to 18.9 ounces of
product per 10,000 gallons of
water in the system initially.
Add 1.5-9.5 ounces of
product per 10,000 gallons of
water to maintain control.
Oilfield water treatment and
water floods
Oilfield water treatment and
water floods
Ready to use
1448-103
1448-395
9386-3
9386-28
Open Pour
Open Pour
Soluble
concentrate
1448-104
Add 2.1 pounds of product to
1000 gallons of drilling fluid
to produce a 2500ppm
concentration initially. Add
0.30 pounds of product to
1000 gallons of drilling fluid
to produce a 350ppm
concentration to maintain
control.
Add 5.22 pounds of product
to 1000 gallons of drilling
fluid to produce a 625ppm
concentration initially. Add
0.73 pounds of product to
1000 gallons of drilling fluid
to produce an 88ppm
concentration to maintain
control.
For water soluble packaging:
One pound per 191 gallons
initially then one pound per
108
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Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
1363 gallons to maintain
control.
Soluble
concentrate
33753-25
Add 1.67 pounds of product
to 1000 gallons of drilling
fluid to produce a 200ppm
concentration initially. Add
1.25 pounds of product to
1000 gallons of drilling fluid
to produce a 150ppm
concentration to maintain
control.
Oilfield Drilling Muds and
work over or completion
fluids
Soluble
concentrate
1448-104
9386-13
33753-25
Open Pour
Ready to use
1448-103
9386-3
Open Pour
Add 175-182 pounds of
product to 1000 barrels of
drilling fluid to produce a
500-520ppm concentration.
For best results add product
in a thin stream to the pit
while drilling fluid is
circulating.
Add 75 pounds of product to
1000 barrels of drilling fluid
to produce a 2080-2500ppm
concentration. For best
results add product in a thin
stream to the pit while
drilling fluid is circulating.
109
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Use Site
Formulation
Method of
Application
Application Rate/ No. of
applications
Use Limitations
Ready to use
1448-395
9386-28
Add 75 pounds of product to
1000 barrels of drilling fluid
to produce a 2080ppm
concentration. For best
results add product in a thin
stream to the pit while
drilling fluid is circulating.
Wood Preservatives
Utility Poles, pilings,
timbers, solid and laminated
wood products.
Pelleted solid
7969-162
71406-5
Technical
Chemical:
7969-16
Applied in
treatment holes
drilled into wood
product to be
treated.
Drill three 7/8 in. diameter by
14 in. long holes at a steep
angle (45 deg or greater) in a
spiral patter starting at ground
line. Apply 70 grams of end
use product into each hole.
Do not overfill treatment
hole. Add liquid accelerant if
desired to treatment hole.
Plug treatment hole with a
tight fitting treated wooden
dowel, removable plastic plug
or other suitable cap.
For wood in ground contact, the first hole should
start at or slightly below ground line and should
be arranged in a spiral pattern covering the
treatment zone with about 6" to 12" vertically
between holes.
An accelerant of a 1% solution of copper
napthenate in mineral spirits may be added to
treatment holes after application of the product
and is designed to speed up the decomposition and
release of the active fumigant inside the wood
product. Keep accelerant away from product
except when in treatment holes, which should be
plugged immediately after they combine.
Not to be used indoors or underneath indoor
structures.
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Appendix B. Table of Generic Data Requirements and Studies Used to Make the
Reregistration Decision
This section is currently not available.
Ill
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Appendix C. Technical Support Documents
Additional documentation in support of this RED is maintained in the OPP docket,
located in room S-4400, One Potomac Yard (South Building), 2777 S. Crystal Drive, Arlington, VA 22202. It
is open Monday through Friday, excluding legal holidays, from 8:30 am to 4 pm.
All documents, in hard copy form, may be viewed in the OPP docket room or
downloaded or viewed via the Internet at the following site: http://www.regulations.gov
These documents include:
Health Effects Support Documents
Dazomet: Updated Final Revised HED Chapter of the Reregi strati on Eligibility Decision
Document (RED). Smith, C. et al.; D354014; June 24, 2008.
Mode of Action, Eye Irritation, and the Intra-Species Factor: Comparison of Chloropicrin and
MITC. Lowitt, A. and Reaves, E.; D293356; TXR 0054860; June 25, 2008.
The Health Effects Division's Response to Comments on EPA's Phase 5 Reregi strati on
Eligibility Decision Document for Dazomet. Smith, C.; D306858; June 18, 2008.
Environmental Fate and Ecological Effects Support Documents
Revised Environmental Fate and Ecological Risk Assessment For Dazomet. Khan. F. and
Felkel, J.; D306855; April 8, 2008.
Response to Phase 5 Public Comments on the Phase 4 Dazomet Environmental Fate and
Ecological Risk Assessment. Khan, F., and Felkel, J.; D306854; April 2, 2008.
Biological and Economical Analysis Support Documents
Assessment of the Benefits Soil Fumigants (Methyl Bromide, Chloropicrin, Metam-Sodium,
Dazomet) Used by Forest Tree Seedling Nurseries. (Chiri, D. and Donaldson, D. Dated April 19,
2007) EPA-HQ-OPP-2005-0125-0044
Assessment of the Benefits of Soil Fumigation with Methyl Bromide, Chloropicrin, Dazomet,
Metam Potassium and Metam Sodium for Use in Raspberry Nurseries, Fruit and Nut Deciduous
Tree Nurseries, and Rose Bush Nurseries in California. (Faulkner, J., and Yourman, L., Dated
April 20, 2007) EPA-HQ-OPP-2005-0125-0045
Assessment of the Benefits of Soil Fumigation with Chloropicrin, Methyl Bromide, Metam-
sodium, and Dazomet In Strawberry Nursery Runner Production. (Yourman, L., and Smearman,
S., Dated April 19, 2007) EPA-HQ-OPP-2005-0125-0054
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Assessment of the Benefits of Soil Fumigation with Chloropicrin, Methyl Bromide, Metam
Sodium and Dazomet in Ornamental Production. (Chiri, A., and Wyatt, T., Dated April 18,
2007) EPA-HQ-OPP-2005-0128-0060
Response to Phase 5 BEAD Related Public Comments Received on the Reregi strati on of
Chloropicrin, Dazomet, Metam Potassium, Metam Sodium, and Methyl Bromide. (Donaldson,
D. et al., Dated June 2008)
Review of Stakeholder Submitted Impact Assessments of Proposed Fumigant Buffers,
Comments on Initial Buffer Zone Proposal, and Case Studies of the Impact of a Flexible Buffer
System for Managing By-Stander Risks of Fumigants. (Wyatt. T., et al, Dated June 2008)
Antimicrobial Assessment Support Documents
Dazomet Antimicrobial Risk Mitigation Paper. Garvie, H., Dated June 2, 2008.
Dazomet: Revised Occupational and Residential Exposure Assessment of Antimicrobial Uses for
the Reregi strati on Eligibility Decision (RED) Document. Walls, C.; D Dated June 2008.
Phase 6 Response to Substantive Public Comments on Antimicrobials Division's Occupational
and Residential Assessments for the Reregi strati on Eligibility Decision (RED) Documents for
the following chemicals: Methylisothiocyanate (MITC), Metam Sodium, Dazomet, and
Chloropicrin. Walls, C.; February 14, 2008.
Buffer Zone Credits Support Document
Factors Which Impact Soil Fumigant Emissions - Evaluation for Use in Soil Fumigant Buffer
Zone Credit Factor Approach. Dawson, J. and Smith, C.; D306857; June 9, 2008.
Risk Management Support Documents
SRRD's Response to Phase 5 Public Comments for the Soil Fumigants. Rice, M. and McNally,
R.; July 2008.
Risk Mitigation Options to Address Bystander and Occupational Exposures from Soil Fumigant
Applications. EPA-HQ-OPP-2005-0128-0031.
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