In a final rule, the EPA has established emergency time-limited maximum permissible levels for residues or tolerances for the fumigant methyl bromide in or on harvested imported or domestic agricultural commodities. The tolerances fall under the emergency exception provisions of Section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).
Phaseout Completed in 2005
Released into the atmosphere, methyl bromide depletes the Earth’s protective ozone layer, allowing increased ultraviolet radiation to reach the Earth’s surface. The 1987 Montreal Protocol on Substances that Deplete the Ozone Layer defined “methyl bromide” as a Class I ozone-depleting substance and required its phaseout by 2005. However, the protocol allowed that methyl bromide can continue to be applied for critical uses and quarantine and preshipment uses. EPA’s current rule is granting exceptions to the methyl bromide for quarantine uses on 36 commodities. The emergency tolerances are effective from March 1, 2018, to December 31, 2020. Methyl bromide is a restricted use pesticide that may be used by only certified applicators and is prohibited for domestic use.
Needed for Invasive Species
The Agency notes that the methyl bromide quarantine exception responds to submissions from the Plant Protection and Quarantine (PPQ) division of the U.S. Department of Agriculture to target invasive, nonindigenous quarantine plant pests and prevent the introduction and/or spread of any new or recently introduced foreign pest(s) to any U.S. geographical location. After having reviewed the submissions, the EPA determined that emergency conditions existed and that the criteria for approval of these quarantine exemptions were met.
Risk Assessment
The Federal Food, Drug, and Cosmetic Act (FFDCA) allows the EPA to establish a tolerance only if the Agency determines that the tolerance is safe. The FFDCA defines “safe” to mean that “there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.” Exposure includes exposure through drinking water and in residential settings but does not include occupational exposure.
To support an exception to a banned substance and the associated tolerances, the EPA must conduct a range of risk assessments. For methyl bromide, the Agency’s assessments addressed dietary exposure from food and feed uses, dietary exposure from drinking water, nondietary exposure, and cumulative effects from substances with a common mechanism of toxicity. Risks addressed in the Agency’s review included risks to children and aggregate risks.
Exposure Near Ports
While deciding that neither the dietary assessments, cumulative effects assessments, nor risk assessments could lead to the conclusion that the exception should not be approved, the Agency does note that there is potential for residential bystander inhalation exposure in and around port areas where postharvest commodity fumigation treatment takes place. To address this concern, methyl bromide labels include directions to establish buffers to reduce bystander exposures to levels that do not exceed the Agency’s level of concern.
EPA’s final rule was published in the March 1, 2018, FR.