The large amount of environmental research information available for chlorpyrifos, along with experiences of more than 45 years of use, has supported continuous improvements in product use practices that support environmental stewardship. One outcome of the vigilance of regulators and manufacturers, in cooperation with growers and professional applicators, has been identification of best management practices that reduce the likelihood of environmental impacts during product use. Many of these best practices have been incorporated into product labeling as either mandatory requirements or advisory guidance for users.

General Use Precautions

The foundation of “good agricultural practice” is simple: Use the amount of pesticide necessary for effective pest management but no more than that. Chlorpyrifos product labels contain crop- and pest-specific advice on the application rate and frequency to be used for effective crop protection. Limitations are provided for maximum single application rate and seasonal limits on applications, and for many crops the waiting period between applications may also be specified.

For protection of aquatic habitats, direct applications to water are prohibited. Extra care is required in disposing of empty containers, wastes, and equipment wash waters. Special precautions are required for protection of waterways where irrigation may be practiced. For example, flood irrigation is not allowed within 24 hours following a soil surface or foliar application.

To protect honeybees, applications are not allowed on blooming crops or if bees are visiting the treatment area.

Spray Drift Management

As for all insecticide products, management of sprays to minimize offsite movement (spray drift) and contamination of waterways or other sensitive areas during chlorpyrifos applications is required. For chlorpyrifos products, no-spray zones around bodies of water such as rivers, lakes, and marshes are required, and these range from 25 feet for ground sprayers to 150 feet for aircraft sprays. Chlorpyrifos product labels also provide guidance on application practices and equipment to be employed for minimizing offsite spray drift, and these include recommendations for spray nozzles that produce coarser, less drift prone particles.

Further Resources

Pesticide Container Recycling, CropLife America

Pesticide Spray Drift Management, CropLife America

Pollinator Protection, CropLife America