EPA Takes Action to Protect Human Health and the Environment by Proposing Cancellation of Pentachloronitrobenzene
Released on September 23, 2022
In support of the Biden-Harris Administration's commitment to making evidence-based decisions to protect human health and the environment, the U.S. Environmental Protection Agency (EPA) is releasing a proposed final decision for pentachloronitrobenzene (PCNB) that proposes to cancel all registrations of this pesticide. The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) requires EPA to review pesticides every 15 years to ensure that risk assessments reflect the best available science, and to ensure that registered products in the marketplace do not present unreasonable adverse effects to human health and the environment. The proposed final decision is part of a multi-step process to identify risks of concern as well as actions that can mitigate these risks.
PCNB is a fungicide used to control plant diseases in both agricultural and non-agricultural settings. Agricultural use sites consist of broccoli, cabbage, kale, potato, and other vegetable crops. Non-agricultural use sites include turf at golf courses, athletic fields, and industrial parks, sod farms, and flowering bulbs and other ornamentals.
The 2021 ecological risk assessment identified risks of concern to fish, amphibians, aquatic invertebrates, aquatic plants, birds, reptiles, mammals, and bees. The ecological risk assessment also identified unique risks of concern for PCNB and its degradates to persist in the environment, to bioaccumulate in the aquatic food chain, and to be subject to long-range transport. Residues have been found in soil, plants, air, water, and animals at long distances from areas where it is used.
The 2021 draft human health risk assessment was based on adverse effects on the thyroid and identified potential non-cancer risks of concern from PCNB exposure to bystanders from spray drift and to users of collegiate and professional athletic fields from direct application to those areas. The risk assessment identified potential occupational handler and post-application risks of concern from exposure to PCNB when used on crops such as flowering bulbs and woody ornamentals.
Manufacturing impurities in PCNB formulations are also associated with potential human health risk concerns, including potential cancer and non-cancer risk concerns for bystanders and users of collegiate and professional athletic fields. The risk assessment also identified potential cancer and non-cancer risks of concern from exposure to impurities for occupational handlers and post-application workers across multiple use sites, including ornamental plants and sod farms.
Based on the significant ecological and human health risks posed by PCNB and limited benefits from the current uses of PCNB, EPA is proposing to cancel all registrations of PCNB. EPA’s proposed action will align the United States with many other pesticide regulatory authorities, including those found in Australia, Canada, New Zealand, and the European Union.
EPA has worked with the U.S. Department of Agriculture and industry stakeholders to identify viable fungicide alternatives including azoxystrobin, pyraclostrobin, tebuconazole, propiconazole and others. These alternatives are discussed in EPA’s June 2022 benefits assessment memo for PCNB. In addition, crop rotation and Bacillus subtillus, a biopesticide, are also alternatives to PCNB for controlling some target pests.
Upon publication of the Federal Register notice, public comments will be accepted for 60 days in the PCNB registration review docket EPA-HQ-OPP-2015-0348 at www.regulations.gov.
After considering comments on the proposed final decision, EPA intends to take the next step in the registration review process, which is to proceed with the final decision. In accordance with section 6(b) of FIFRA, the Agency may then initiate proceedings to cancel the registrations of pesticide products containing PCNB. There are no immediate use restrictions or limitations for users of products containing PCNB with the issuance of this proposed final decision.