Recent federal legislation will reduce the number and amounts of pesticides available to farmers. But producers can start planning now for these changes by reducing their reliance on pesticides with the greatest potential for harm to human health and the environment.

Congress unanimously passed the 1996 Food Quality Protection Act (FQPA) to improve food safety. It amends earlier legislation regulating food safety and tolerances and pesticide registration and use. The FQPA mandates that the Environmental Protection Agency (EPA) reassess all existing tolerances for pesticides taking into account additional sources of exposure and establish safety factors to protect infants and children. A tolerance is the maximum legal level of a pesticide residue on food or animal feed that EPA considers safe.

FQPA creates a single, health-based safety standard for pesticide residues in food. EPA may lower tolerances by a factor of up to ten for pesticides to protect infants and children. FQPA takes into account the sum of pesticide exposures from food, water, and indoor and outdoor air. FQPA also requires screening and testing for endocrine disruptors-chemicals that affect human growth and development.

EPA will review highest risk pesticides first-those with the greatest potential for harm. The phase out of these pesticides (called List One pesticides because they are to be reviewed first) will affect growers in the year 2000 growing season.

“First to be reviewed are pesticides known to directly affect the human
nervous system, such as organophosphates and carbamates,” says Michelle Miller, coordinator of the Pesticide Use and Risk Reduction project.

Lower-risk pesticides are on a fast track for review and registration to increase alternatives for producers who have to switch from riskier pesticides. All pesticide registrations will be reviewed on a 15-year cycle.

The Pesticide Use and Risk Reduction project is funded by pesticide overcharge funds administered by the Wisconsin Department of Justice with matching funds from the UW-Madison Center for Integrated Agricultural Systems (CIAS), and other sponsoring organizations who participate as Project Partners (see sidebar). Project Partners direct the project, identify research priorities in their crop areas, and provide FQPA and pesticide options information to their members.

Project Partners

Michael Fields Agricultural Institute
Wis. Apple Growers Assn.
Wis. Berry Growers Assn.
Wis. Corn Growers Assn.
Wis. Farm Bureau Federation
Wis. Farmers Union
Wis. Federation of Cooperatives
Wis. Fresh Market Vegetable Growers Assn.
Wis. Ginseng Growers Assn.
Wis. National Farmers Organization
Wis. Potato and Vegetable Growers Assn.
Wis. Rural Development Center
Wis. Soybean Assn.
Wis. State Cranberry Growers Assn.

The Pesticide Use and Risk Reduction project works with teams of researchers and farm organization members to identify profitable options to List One pesticides and share them with farmers. The three teams work on field crops, fruits, and vegetables. The Field Crops Team is co-chaired by Chris Boerboom, UW-Madison Agronomy Department, and Jeff Polenske, Polenske Agronomic Consulting of Appleton, Wisconsin.

The risk cup concept

FQPA is changing the way that risk is viewed. In the past, each pesticide had several tolerances assigned to it-one for each crop use.

“Picture a teacup as holding the amount of pesticide it takes to reach a given exposure limit,” Miller explains. “Before FQPA, each pesticide had several of these risk cups assigned to it for each of its uses, but under FQPA each pesticide will be assigned only one.” All of the uses of a particular pesticide-on crops, buildings, and even on pets-will need to share one risk cup. Pesticides with similar modes of action, like organophosphates and carbamates, may be assessed cumulatively within a single risk cup. This level of analysis will help better evaluate the full risk from exposure to more than one pesticide through food, water, air, and the living environment.

For example, chlorpyrifos (trade names include Lorsban and Dursban) is a commonly used organophosphate pesticide on List One. In the past, risk was primarily based on single source dietary exposure. The first phase of the EPA assessment will assign chlorpyrifos one risk cup for all uses. The second phase of the assessment will assign one risk cup to the family of chemicals to which chlorpyrifos belongs.

A proactive response

“Many producers would like to reduce their use of the riskiest pesticides, and this legislative change means producers will need new information about pesticide options,” says Miller. The table above shows several List One chemicals and some options for replacing them.

The use of Integrated Pest Management (IPM) in field crops has proven to save producers money and lessen health risks, for example, by reducing pesticide rates in combination with tillage, expanded crop rotations, and other cultural practices. Also, newer and less risky pesticides (Lists Two and Three pesticides) can substitute for List One pesticides.

Commonly used FQPA List One field crop pesticides and some options
Pesticides are shown by use, chemical name, and trade name

Commonly used FQPA List One field crop pesticides and some options

Pesticides are shown by use, chemical name, and trade name

Corn rootworm
Chlorpyrifos-Lorsban, Dursban
Ethoprop-Mocap
Phorate-Thimet
Terbufos-Counter
Carbofuran-Furadan
Chlorethoxyfos-Fortress
Tebupirimphos-Aztec

Reduced risk options
Tefluthrin-Force
Fibronil-Regent

Field practice options
Use 75 % label rate at planting; crop rotations; tillage

Annual broadleaf weeds
Atrazine;
Bromoxynil-Buctril
Cyanazine-Bladex
EPTC-Eradicane
Simazine-Princep
(Note: Loss of triazines may hasten resistance development or weed species shift for other herbicide modes of action. Triazine herbicides are three of a limited number of effective soil-applied broadleaf herbicides.)

Reduced risk options
Dicamba-Banvel, Clarity, premixes
Halosulfuron-Permit
Primisulfuron –Beacon, premixes
Flumetsulam-Python, premixes
For herbicide resistant hybrids:
Imazethapyr + imazepyr-Lightning
Glyphosate-Roundup
Glufosinate-Liberty

Field practice options
Crop rotations with cultivtion or early application; variable rate; rotary hoeing; scouting

Annual grass weeds
Acetochlor-Harness, Surpass
Alachlor-Lasso
Metolachlor-Dual
EPTC-Eradicane
Pendimethalin-Prowl
(Note: loss of acetanilides may hasten resistance development or weed species shifts for other herbicide modes of action.)

Reduced risk options
Nicosulfuron-Accent
Rimsulfuron-Basis
Difluthiamide-Axiom
For herbicide resistant hybrids:
Imazethapyr + imazapyr-Lightning
Glyphosate-Roundup
Glufosinate-Liberty
Sethoxydim-Poast Plus

Field practice options
Reduced rate with cultivation or early application; rotary hoeing; cultivation; scouting; cover crops

Wireworm, cutworm, seed maggot, white grubs
Chlorpyrifos-Lorsban
Chlorethoxyfos-Fortress
Ethoprop-Mocap
Phorate-Thimet
Tebupirimphos-Aztec
Terbofos-Counter
Diazinon (seed maggot)
Permethrin (cutworm)-Ambush, Pounce

Reduced risk options
Tefluthrin-Force
Fibronil-Regent
For cutworms:
Esfenvalerate-Asana
Cyhalothrin-Warrior

Field practice options
Bait stations; increased tillage

For more information about the Pesticide Use and Risk Reduction project, contact Michelle Miller at (608) 262-7135, e-mail mmmille6@facstaff.wisc.edu

EPA also has a toll-free FQPA hotline at 1-888-322-1323 and a World Wide Web site at http://www.epa.gov/oppfead1/fqpa

Contact CIAS for more information on this research.

Published as Research Brief #42
September, 1999