Cyfluthrins Comments Submitted

The NCC submitted comments to EPA on their draft human health and ecological risk assessment for cyfluthrins (baythroid).

Published: February 16, 2018
Updated: February 16, 2018

February 13, 2018

Office of Pesticide Programs
Regulatory Public Docket (7502P)
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., NW Washington, DC 20460

RE: Docket ID Number EPA-HQ-OPP-2010-0684

Dear Ms. Waleko:

The National Cotton Council (NCC) appreciates the opportunity to comment on the U.S. Environmental Protection Agency’s (EPA) “Cyfluthrin and Beta-Cyfluthrin: Draft Human Health Risk Assessment for Registration Review”, “Cyfluthrin and Beta-Cyfluthrin: Acute and Chronic Aggregate Dietary (Food and Drinking Water) Exposure and Risk Assessment for Registration Review,” and “Cyfluthrin and Beta-Cyfluthrin: Occupational and Residential Exposure Assessment for Registration Review.”  The NCC urges EPA to recognize the long history of this mode of action (MOA) to control insects that damage our crops and its importance for resistance management scenarios.  As EPA urges producers to recognize the value of rotating chemical MOA’s for resistance management purposes, EPA must recognize rotation is not possible unless there are multiple MOA’s available.  The pyrethroid group, including cyfluthrin and beta-cyfluthrin, serve critical value in managing destructive cotton pests such as budworms, bollworms, plant bugs, and stinkbugs.

The NCC is the central organization of the United States cotton industry.  Its members include producers, ginners, cottonseed processors and merchandizers, merchants, cooperatives, warehousers and textile manufacturers.  A majority of the industry is concentrated in 17 cotton-producing states stretching from California to Virginia. U.S. cotton producers cultivate between 9 and 12 million acres of cotton, with production averaging 12 to 18 million 480-lb bales annually. The downstream manufacturers of cotton apparel and home furnishings are located in virtually every state. Farms and businesses directly involved in the production, distribution and processing of cotton employ more than 125,000 workers and produce direct business revenue of more than $21 billion.  Annual cotton production is valued at more than $5.5 billion at the farm gate, the point at which the producer markets the crop.  Accounting for the ripple effect of cotton through the broader economy, direct and indirect employment surpasses 280,000 workers with economic activity of almost $100 billion. In addition to the cotton fiber, cottonseed products are used for livestock feed and cottonseed oil are used as an ingredient in food products, as well as being a premium cooking oil.

First, the NCC appreciates the EPA’s thorough review of merited science that demonstrates the safety of these products with regards to human health.  We also urge EPA to continue cooperation with the Council for the Advancement of Pyrethroid Human Health Risk Assessment (CAPHRA) to refine the risk assessment by reducing safety and uncertainty factors that are not needed to protect human health. The Insecticide Resistance Action Committee (IRAC) MOA Group 3 Sodium channel modulators, (Mode of Action Classification Scheme, July 2017, Version 8.3), has a long history of safe use when used according to labels.

We think it is notable that the Risk Assessments demonstrate no scientific evidence for carcinogenicity to humans, no concern for mutagenicity, no acute dietary risk of concerns, no residential handler risk estimates of concern, no dermal risk estimates of concern for agricultural uses of cyfluthrin and beta-cyfluthrin (both seed treatment and non-seed treatment uses), using baseline clothing (i.e., long pants, long-sleeved shirt, shoes and socks) and no PPE, and no acute aggregate risk estimates of concern.  These products are clearly of low, if any, human health concerns when used as labeled.  The NCC believes refinements that result in further reductions tothese conservative uncertainty factors will allow continued and/or additional uses while supporting the human health safety of these products.

The NCC notes that EPA conducted the Acute and Chronic aggregate dietary exposure assessment using DEEM-FCID version 3.16.  EPA notes this bases information on food consumption data from 2003-2008.  The NCC urges EPA to use more recent data (2005-2010) contained in DEEM-FCID Version 4.0.  However, for the acute and chronic dietary risk assessment, EPA states on page 8 under results, “Risk estimates are not of concern for the general U.S. population or any population subgroup.”

The NCC urges EPA to recognize the benefits of the pyrethroid group of chemistries, which includes cyfluthrin and beta-cyfluthrin.  The NCC reminds EPA that the Pyrethroid Working Group (PWG) contracted AgInformatics to conduct an extensive analysis with different methodologies to determine the value of pyrethroids (  The main data used were the extensive GfK Kynetec data on insecticide use by U.S. crop farmers for 2012-2014.  Below are a few critical considerations for cotton production resulting from the AgInformatics study that we feel deserve your focused consideration:

  • At least 80% of cotton farmers identified six features of pyrethroids as very important. 
    1. Protecting yield
    2. Family and worker safety
    3. Consistent insect control
    4. Crop price
    5. Production and application cost
    6. Long-lasting insect control
  • Pyrethroids reduced crop damage as much as 65% in cotton.  Targeted pests in cotton differ pre-bloom and post-bloom.  Pre-bloom, the primary pest is thrips, while plant bugs and aphids are minor targets. Post-bloom, the targeted pests shift to bollworms, stink bugs, and plant bugs.
  • For cotton, stink bugs are the primary target pest of pyrethroid insecticides in foliar-based systems, with a 43.8% share of all foliar treated acres. 
  • Lepidopterans are overwhelmingly the primary target pest in soil-based systems, with an 86.3% share of product treated acres.
  • The estimated value to the farmer for foliar pyrethroid treatments was $36.62 per treated acre pre-bloom and $50.06 per treated acre post-bloom.  

The NCC appreciates the opportunity to comment on EPA’s “Cyfluthrin and Beta-Cyfluthrin: Draft Human Health Risk Assessment for Registration Review”, “Cyfluthrin and Beta-Cyfluthrin: Acute and Chronic Aggregate Dietary (Food and Drinking Water) Exposure and Risk Assessment for Registration Review, and “Cyfluthrin and Beta-Cyfluthrin: Occupational and Residential Exposure Assessment for Registration Review.”


Steve Hensley
Senior Scientist, Regulatory and Environmental Issues
National Cotton Council