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WSSA Pesticide Stewardship Series 11- Proper Disposal of Pesticides Extends Far Beyond the Container

A farmer, a local lawn and garden supply store, and a department store chain were fined recently for pesticide disposal violations. In each of these cases, the pesticide product itself was disposed of improperly.

“Regulations on proper pesticide disposal govern the product and much more,” explains Fred Fishel, Ph.D., Professor of Agronomy and Director, University of Florida/Institute of Food and Agricultural Sciences Pesticide Information Office. “They address excess or damaged product, unused spray mixture, rinsate from containers and application equipment, empty containers, leftover treated seed, contaminated clothing and personal protective equipment, material from cleanup of spills and leaks, and other pesticide residues. If anything contains or is contaminated with a pesticide, appropriate disposal is a must.”

It is important to note that state and local laws regarding pesticide disposal may be stricter and more detailed than federal requirements on the pesticide label. Also, many disposal facilities can accept only certain types of waste.

Here are a few important tips about pesticide disposal:

Excess Product. Avoid having to dispose of excess product by purchasing only the amount needed. Excess pesticides can be given to another qualified user (if the product registration has not expired), taken to a qualified disposal site or collection location, or disposed of through a waste transporter. Special disposal programs may exist for products missing identifying labels.

Unused Spray or Dip Mixture. Whenever possible, eliminate or minimize excess spray or dip mixture by practicing careful measurement, calibration and application. Apply excess mixture to another labeled site or follow all disposal regulations.

Rinsate. Rinse the pesticide container or spray equipment over an impermeable surface and in a way that allows recovery of the rinsate. If the rinsate contains no debris, it can be used the same day as part (up to 5%) of the water (or other liquid) portion of the next spray mixture of that chemical. Rinsate can also be applied to the original site, provided registered rates are not exceeded and the application is consistent with label directions. If practical, take clean water to the treatment site to rinse equipment immediately after the application.

Never pour excess product, unused spray/dip mixture or rinsate onto a roadway or into a sink, toilet, sewer, street drain, ditch or water body. Do not mix pesticides or load or rinse equipment near a wellhead. Pesticides may interfere with the operation of wastewater treatment systems, pollute waterways or harm non-target organisms. Many municipal systems are not equipped to remove all pesticide residues.

Empty Containers. Rinse containers of liquid products thoroughly at the mixing site as soon as they are emptied using the triple rinse method or a pressure rinser. Puncture the top and bottom of disposable containers to prevent reuse. When disposable containers holding dry formulations are empty, open both ends to help remove any remaining pesticide.

If containers are non-refillable, high-density polyethylene, there are collection/recycling programs for agricultural and commercial applicators in most states. Contact the Ag Container Recycling Council for more information. Where there is no recycling program, deposit all empty containers in a licensed sanitary landfill. Do not reuse or stockpile empty disposable containers.

If containers are refillable/returnable, follow all rinsing and collection instructions provided by the manufacturer, distributor or retailer.

Leftover Treated Seed.  The best way to dispose of a small quantity of leftover seed that has been treated with a pesticide is to plant it in an uncropped area of the farm or garden. Use the normal seeding rate and depth and plant at the proper time of year. Do not put treated seed in your compost pile or leave it on the soil surface. Additional options exist for large quantities, but consult first with state and local authorities to make sure you are in compliance with appropriate regulations.

Contaminated Clothing. Discard clothing that has been drenched or heavily contaminated with concentrated product. Most of this clothing can be discarded as normal solid waste. However, if the pesticide is regulated as hazardous waste, the contaminated clothing may have to be disposed of as hazardous waste.

Personal Protective Equipment (PPE). Discard PPE (or a PPE component) that has been damaged or designated as one-time use, or has expired or reached its use limit. Follow the most strict disposal directions, which may be state or local laws, the pesticide label or the PPE manufacturer’s instructions.

Material from Clean-up of Spills or Leaks. Absorbent material such as pet litter, sawdust, or soil should be used to absorb small liquid pesticide spills or leaks and any water/detergent mixture used to clean the spill area. The absorbent material and any soil contaminated in a spill must be placed in a suitable container for proper disposal and treated as pesticide waste. Sweep up dry spills and return the product to the container only if any contamination with soil, etc. will not impact use. Contact your state to determine notification and cleanup requirements that may be applicable to a larger spill or leak.

Containment Pad/Sump Residue. A containment pad/sump is a safety system designed to contain and recover rinsate, spills, leaks, etc. Any solids left in the containment pad/sump should be dried and spread evenly over a large part of the field in accordance with label directions. If this is not possible, the solids should be taken to an approved waste disposal site.

“Proper pesticide disposal depends upon state and local regulations, the pesticide(s) involved, the waste classification, the quantity of waste and the disposal facility,” says Fishel. “Ultimately, the only acceptable approach is to be diligent with pesticides from start to finish. Purchase and prepare only what you need, avoid contamination and spills, and discard the container and other pesticide wastes according to the instructions on the pesticide label and all other laws.”

The Association of American Pesticide Control Officials (AAPCO) provides contact information for state offices that regulate pesticides.

Check with your local solid waste management authority, environmental agency or health department to find out whether your community has a household hazardous waste collection program.

Some Resources on Pesticide Disposal:

This is the final segment in a series on pesticide stewardship sponsored by the Weed Science Society of America.


About the Weed Science Society of America

The Weed Science Society of America, a nonprofit scientific society, was founded in 1956 to encourage and promote the development of knowledge concerning weeds and their impact on the environment. The Weed Science Society of America promotes research, education and extension outreach activities related to weeds, provides science-based information to the public and policy makers, fosters awareness of weeds and their impact on managed and natural ecosystems, and promotes cooperation among weed science organizations across the nation and around the world. For more information, visit www.wssa.net.