Division of Environmental Quality fact sheet
Division of Environmental Quality Director: Kyra Moore

This fact sheet provides guidance for pesticide applicators on how to properly manage pesticide rinsate. The proper management of pesticide rinsate helps protect human health and the environment while also allowing the applicator to utilize as much of the pesticide product for its intended purpose as possible. Always read and follow the pesticide label before using any pesticide because the label is the law.

Most pesticide labels require pesticide containers be rinsed prior to recycling or disposal to ensure as much of the product is cleaned from the container as possible. In addition to rinsing product containers, pesticide application equipment needs thorough rinsing when switching between products and before storage. Below are some common questions with answers regarding pesticide rinsate management. 

Q: Can pesticide rinsate be used to make up the next batch of like formulation?  

A: Yes, as long as the amount of pesticide in the rinsate plus the amount of pesticide product in the mixture does not exceed the labeled rate for the target site. 

Q: Can rinsate be reapplied to a labeled site? 

A: Yes, as long as the labeled rate isn’t exceeded over the site.

Q: Can pesticide rinsate be discharged to a publicly owned treatment works (POTW)? 

A: It depends. Volume, concentration and rate of discharge of the rinsate are factors likely considered by a POTW before allowing the discharge to occur. Always contact the POTW first to ask for permission to discharge into the system. 

Q: What if I am unsure what pesticide product the rinsate resulted from? 

If you are a Missouri farmer or householder you can solidify the rinsate and discard in the trash or dispose of the rinsate the same as a business as noted next. If you are a business (e.g., commercial pesticide applicator) you would need to conduct a hazardous waste determination on the rinsate in order to determine proper disposal. Managing Pesticide Waste - PUB2596 is a fact sheet developed for business management of pesticide waste.     

Best management practices associated with managing pesticide rinsate:

  • Never store pesticide rinsate unless unavoidable or for only a short period of time.
  • If you have to store pesticide rinsate label the container with the pesticide product name followed by rinsate.
  • Never mix rinsates from two different pesticide products unless the label allows for such mix.
  • Pesticide rinsate should be managed with the same precautions as undiluted product.

Best management practices associated with rinsing pesticide containers/application equipment:

  • Always follow the label for each pesticide while rinsing the container.
  • Using an impervious rinse pad to collect rinsate for reuse.
  • Rinse containers immediately after emptying to avoid allowing product residue to dry making it more difficult to effectively clean the container.
  • Always don personal protective equipment when rinsing pesticide containers/application equipment.
  • Do not rinse pesticide containers or equipment within 100 feet of environmentally sensitive areas such as wells, sink holes and bodies of water.

Additional information

Managing Pesticide Waste - PUB2596
Missouri Department of Agriculture Bureau of Pesticide Control

For environmental emergencies contact the Department’s spill line at 573-634-2436.

Nothing in this document may be used to implement any enforcement action or levy any penalty unless promulgated by rule under chapter 536 or authorized by statute.

For more information