Methyl Bromide for Post Harvest UsesAnticipated Label Changes
Methyl Bromide and Alternatives in Food PlantsKansas State University
May 11-13, 2010David L. McAllister
Chemtura Corporation
Methyl Bromide ReregistrationPre-plant Uses• Amended labels – late 2010• Further amendments in 2011
Methyl Bromide ReregistrationPost Harvest Uses• Amended labels – 2011 or 2012
Post Harvest Label Changes
• Tolerances• Fumigation Management Plans• Buffer Zones• Posting and Notification• Record Keeping• Respiratory Protection• Monitoring• Minimum Aeration Times
Tolerances• Based on residue studies conducted in the mid-
1990’s by the Methyl Bromide Industry Panel• Will be expressed as methyl bromide instead of
bromide ion• Will be based on crop groupings rather than
individual crops.
Tolerances - 2• A few tolerances will be revoked, and some uses will be
removed from the label.
Commodity Tolerance Disposition
Alfalfa Hay Revoke Remove Use
Cottonseed Revoke Remove Use
Cumin Seed Revoke Not currently registered
Mangoes Revoke Not currently registered
Papayas Revoke Not currently registered
Pomegranates Revoke Not currently registered
Timothy Hay Revoke Not currently registered
Fermented malt beverage Revoke Not currently registered
Dog food Revoke Tolerance not required
Ginger roots Revoke Not currently registered
Cereal grains Revoke Not currently registered
Fumigation Management Plan• A Fumigation Management Plan (FMP) will be
required for all fumigations• FMP is the responsibility of the person supervising
the fumigation• No requirement for review or approval by regulatory
authorities• Must be retained for 2 years• Similar to the FMP now required for phosphine
fumigations.
Fumigation Management Plan - 2Required Elements of the FMP• General site information• Fumigator/Applicator information• Treatment and aeration procedures• Buffer zones• Authorized on-site personnel• Personal protective equipment• Posting and notification plans and records• Record keeping• Emergency procedures• Site Security• Hazard communication
FMP DetailsGeneral site information (site address, site operator/owner, phone number)• Type of fumigation (e.g., quarantine, structural, mill, ship)• Description of enclosure/chamber/structure (map or sketch of the facility, volume of treatment area, enclosure materials, commodities fumigated,
maximum rates and dosage times, local exhaust ventilation systems, MeBr destruction/capture systems, proximity to other structures and common walls)
• Estimate of loss/retention rate (methods for evaluating and documenting)• Descriptions and locations of control rooms, storage areas, restricted areas, other work areas, and sensitive surrounding sites (such as homes,
schools, hospitals, employee housing centers)Fumigator/applicator information (license #, address, phone, contact information for person supervising the fumigation, i.e., the
responsible party)Treatment and aeration procedures• Maximum rates and dosage for each commodity• Location of gas introduction site (including map and description)• Leak testing procedures• Interior and perimeter air monitoring of treated areas (methods, procedures, and equipment)Buffer zones (see below for method to calculate treatment and aeration buffer zones based on Agency look-up tables or alternate
methods)Authorized on-site personnel• Fumigators (fumigation workers must be certified applicators, or be working under the direct supervision of a certified applicator)• Other on-site workersPersonal protective equipment (selection, fit-testing, maintenance, storage procedures)Posting and notification (plans, procedures, record of notifications)Record keepingEmergency procedures (evacuation routes, emergency utility shut-offs, locations of telephones, emergency company, local/state/federal
contacts, key personnel and emergency responsibilities in case of an incident, equipment failure, or other emergency).Site securityHazard communication (product labels, material safety data sheets, etc.)
Buffer Zones• Only persons performing or supervising a fumigation
are permitted inside the buffer zone• Two buffer zones for commodity fumigation:
• Treatment – while fumigation is in progress• Aeration – until air discharged from fumigated area contains
<5 ppm methyl bromide• Buffer zone distances based on EPA look-up tables
or alternate methods• Minimum buffer zone – 10 feet• Exceptions
• Occupied structures, if monitored• Non-occupied structures• Transit – roads and railroads
Internal Concentration Data
24 hours
Aeration begins
Gas Release
Treatment Aeration
ppm
vFumigation Concentration Profile
Example Buffer Zones
Treatment buffer zone
Aeration buffer zone
Buffer Zone Table - ExampleBuffer Zones (m) During Treatment Period of 24 Hours or Greater
App Rate(lbs/1,000 ft3) % Release
Volume (1,000 ft3)
10 25 50 100 250 500 750 1,000
1 25 0† 0† 0† 0† 15 35 55 70
2 25 0† 0† 0† 20 45 80 110 135
3 25 0† 0† 5 30 70 115 155 185
4 25 0† 0† 15 45 90 145 195 230
Buffer Zones (m) During Aeration Period of 8 Hours or Less
Application Rate lb/1000ft3
% Release
Volume (1,000 ft3)
10 25 50 100 250 500 750 1,000
175 0† 0† 0† 0† 60 115 160 195
50 0† 0† 0† 0† 0† 65 90 115
275 0† 0† 0† 40 135 225 345 455
50 0† 0† 0† 0† 85 155 210 265
375 0† 0† 0† 85 195 360 550 710
50 0† 0† 0† 40 135 225 345 455
475 0† 0† 40 120 255 495 715 910
50 0† 0† 0† 70 175 315 485 635
Buffer Zone – Alternate Methods• Site-specific modeling
• Use local volumes and ventilation rates
• Models specified by EPA
• One model run could be used for a given facility, as long as conditions do not change
• Site-specific air monitoring• According to EPA criteria
• Number and extent of samples may be practically prohibitive
• Emission mitigation may reduce buffer zones• Improved sealing
• Exhaust scrubbers
Posting and Notification• Exterior of containers of fumigated commodities must
be identified as having been fumigated• Fumigator must provide access to MSDS for workers
who handle the fumigated commodity• Fumigators must notify all residences and
businesses adjacent to sites where fumigation takes place and tell them how they can access the FMP
• Annual notification
• Notify by mail, radio, TV, newspapers, postings in public places
• Fumigant groups are working with EPA to devise acceptable notification schemes
Record Keeping• Certified applicator must maintain records that show:
• Dates of fumigation
• Results of any air monitoring
• Records must be maintained for 2 years, and must be readily available to fumigation workers and other on-site personnel.
• Records must be available on request to• Local, state, tribal, or Federal pesticide enforcement officials
• Any interested individuals in the community.
Respiratory Protection• Respiratory protection is required for all persons in
the treatment area or buffer zones• Greater than 5 ppm – supplied air or SCBA• Between 1 ppm and 5 ppm – supplied air, SCBA, or
cartridge type respirator• Below 1 ppm for an 8 hour TWA – no respiratory
protection required.• EPA is considering changes that will require
respiratory protection at concentrations above an 8 hour TWA of 0.15 ppm
Air Monitoring• Air concentration must be monitored using a direct
reading monitoring device• Label will provide detailed procedures which must be
followed in order to discontinue respiratory protection.
• Monitoring must be continued at least hourly after respiratory protection is discontinued.
Minimum Aeration Times• Four hours if mechanically ventilated using fans• Twelve hours if passively ventilated using windows
and doors only• Exceptions
• In a vacuum chamber that provides at least 4 air changes per hour, ventilation can be discontinued after 10 air changes
• Detection devices with a detection limit of 0.5 ppm or lower can be used to demonstrate that ventilation time can be shortened
• Fumigated commodities can be moved to a storage if the methyl bromide concentration between the stacks is 5 ppm or less, and at least 10 air changes have been completed.
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