Advocacy Update: Persistent Herbicides & EPA Meeting

Example of persistent herbicide damage

The US Composting Council met with officials from the Environmental Pollution Agency’s (EPA’s) Pesticide Re-evaluation Division in Washington, D.C., in August to discuss the issues of the family of pyridine and pyrimidine carboxylic acid herbicides (persistent herbicides, or PH) affecting incoming feedstocks at composting facilities. We met with representatives of various EPA pesticide evaluation departments, EPA’s Department of Resource Recovery & Conservation and representatives from Bayer Crop Sciences and Corteva Agri-Sciences.

During the meeting, we presented information on how these herbicides are entering our facilities, the impossible task of identifying contaminated feedstocks and the potential damage and risk to the industry. We at USCC stressed the importance of the growth of our industry as part of the solution in processing all organic residuals. We stressed specifically the importance of our industry’s role in assisting in the achievement of the EPA-USDA goal of 50% reduction in food waste by 2030.

Dr. Fred Michel, professor and researcher at Ohio State University, presented his work on the effects and damage on plants that were grown in compost-amended potting media. Some of the plants in these tests showed damage in as little as one part per billion concentration of herbicide. Dr. Michel also identified the following needs for additional research.

• Chemical testing to measure concentrations of herbicides in positive samples
• Plant bioassays to screen composts and feedstocks for herbicide contamination
• The development, validation and publication of chemical test methods for the measurement of herbicides in composts at low part per billion concentrations
• Determination of the fate and persistence of recalcitrant herbicides during composting and in soil
• Determination of the sources of PH in composts through compost feedstock testing
• Research on low cost methods to remediate contaminated composts

We concluded the USCC’s presentation with the following requests to EPA with regards to registration of new products and re-registration of existing products in this family of herbicides:

• Limit application of these products to non-harvested crops
• Label as “Apply in place, leave in place”
• Remove the approval for application on ornamental turf-grass
• Improve labeling graphics and instructions for use to highlight the potential contamination issues
• Limit application to professional certified applicators
• Control distribution and track products sold on the internet
• Require manufacturers to provide documented training to professional certified applicators
• Change the registration process for herbicides to require an evaluation of their compostability
• Develop reliable test methods and determine standards for an herbicide to receive approval
• Prohibit retail sales of these products
• Enact penalties and fines for misuse and list the penalty amounts on labels as a deterrent
• Assign liability to both the applicator and the property owner for PH-contaminated material removed from the site of application
• Develop public outreach, training and education materials for state extension personnel on labeling, application and identification of plant damage of PH
• Require manufacturers to provide a list of independent labs that can reliably screen for this class of herbicides at phytotoxic concentrations (one part per billion)
• Require manufacturers to determine the potential residual concentrations of each active PH ingredient after treated materials are composted
• Require manufacturers to investigate cases where compost herbicide phytotoxicity is evident and provide methods to remediate contaminated composts

The EPA has informed us that six of these herbicides that are up for re-registration over the next 12-month period. They are as follows:

• Aminopyralid: The draft risk assessments are scheduled for summer 2020
• Clopyralid: The proposed interim decision is scheduled for spring 2020
• Dithiopyr: The schedule is on hold pending submission of additional data
• Fluroxypyr: The proposed interim decision is scheduled for fall 2019
• Picloram: The draft risk assessments are scheduled for early 2020
• Triclopyr: The draft risk assessments are scheduled for fall 2019

The USCC has formed a PH Task Force under the LEAC to work on filing specific comments and recommendations for these herbicides during the re-registration process. The task force will provide key talking points for members to submit their comments. We encourage all members to submit comments. This information will be made available on the PH webpage along with the link to the EPA website. We will notify members as soon as they become available.

Resources

EPA’s website has additional information on how to report incidents.

The National Pesticide Information Center (NPIC) website has great information on which incident reporting avenue might be best, depending on the type of incident and whether it requires enforcement action:

For more information on this topic, go to the USCC Persistent Herbicides web page.