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.