Back to top

Pesticide Safety and Use

Who can apply pesticides

Farmers who use pesticides may require pesticide applicator licenses or permits according to state and federal law. It is important to check with your state lead agency (SLA) for pesticide regulation to determine what is appropriate in your state.  In general:

  • Farmers who apply restricted use pesticides on their crops need to have a private applicator license or permit.
  • Workers who help someone who is licensed or certified to apply restricted-use materials may also need a license to assist. 
  • Farmers who use only general use pesticides may also require licenses or permits; these requirements vary from state to state.
  • In most states, commercial (for hire) applicators must follow rules that are more restrictive than those of private applicators. 

Please note that the requirements of the EPA Worker Protection Standards (WPS) must still be followed regardless of whether a pesticide license or certification is required.  See the section below on WPS.  As of this printing, the following are contacts who can provide information on specific requirements for pesticide licenses and certification for each state.

Connecticut: 860-424-3369,
Maine: 207-287-2731,
Massachusetts: 617-626-1784,
New Hampshire: 603-271-3550,
Rhode Island:  401-222-4700,
Vermont:  802-828-2431,


All pesticides are poisonous. However, some are more toxic than others. The toxicity of the pesticide is usually stated in the precaution label. For example, a skull and crossbones figure and the signal word “Danger” are always found on the label of highly toxic (Toxicity Class I) materials. Those of medium toxicity (Toxicity Class II) carry the signal word “Warning.” The least toxic materials (Toxicity Class III) have the signal word “Caution.” The toxicity of a pesticide is expressed in terms of oral and dermal LD50. LD50 is the dosage of poison that kills 50% of test animals (usually rats or rabbits) with a single application of the pure pesticide for a given weight of the animal (mg/kg of body weight). The lower the LD50 value, the more toxic the material. Oral LD50 is the measure of the toxicity of pure pesticide when administered internally to test animals. Dermal LD50 is the measure of the toxicity of pure pesticide applied to the skin of test animals. Generally, an oral application is more toxic than a dermal one.

Table 8. Toxicity Categories and Signal Words
I Highly Toxic DANGER and POISON,
plus skull and crossbones symbol
0 to 50 A few drops to 1 tsp
II Moderately Toxic Warning 50 to 500 1 tsp to 2 tsp
III Slightly Toxic Caution 500 to 5,000 1 oz to 1 pint (1 lb)
IV Almost non-toxic Caution more than 5,000 1 pint (1 lb)
Note: certain products may use signal words which do not correlate with LD50 ratings due to some special property of the chemical. For example, chlorothalonil has a very low toxicity (LD50 10,000 mg/kg) yet has DANGER signal words on many of its formulations, due to eye toxicity/injury.

All pesticides listed in this publication are registered and cleared for suggested uses according to federal and state regulations in effect on the date of this publication. Follow current label.

Trade names are used for identification only; no product endorsement is implied, nor is discrimination intended against similar materials.

Warning! Pesticides are poisonous. Read and follow all directions and safety precautions on labels. Handle carefully and store in original labeled containers out of reach of children, pets and livestock. Dispose of empty containers carefully and properly. Contact your State Lead Agency (SLA) for pesticide regulation located in either the state Department of Agriculture or state Department of Environmental Protection for current disposal regulations and guidelines.

Before Using Pesticides

Read and post safety rules and the list of poison control centers. See instructions on safe storage of pesticides in an earlier section of this chapter. You should become familiar with the information on storage and toxicity of pesticides listed in the appendix of this guide. Similar pesticide products may not have the same crop uses. Always be certain the crop is listed on the product label before ordering or using the product.

Do not use concentrations greater than stated on the label. Do not apply more pesticide per acre or more frequently than the fewest number of days between applications recommended by the label.

Instruct your family, co-workers and farm laborers on the safe use of pesticides, protective clothing and reentry regulations concerning pesticides. See section on worker protection standards.

Do not spray or dust when bees are active in the field. Morning or late evening is usually the best time to spray.


  • Read and follow all directions and safety precautions on labels.
  • Store pesticides in original containers, out of reach of children, pets and livestock.
  • Dispose of empty containers immediately in a safe manner and place. Triple rinse.
  • Do not contaminate forage, watersheds or water sources.
  • Become familiar with life cycles of pests to properly time applications.
  • Keep a complete diary of applications: crop, date of planting, pests, weather conditions, materials, date of application and amounts applied.
  • Adhere to farm worker protection standards.

Emergency Information

Human Exposure

If someone has swallowed or inhaled a pesticide or gotten it in the eye or on the skin:

  • Call 911 if the person in unconscious, having trouble breathing, or having convulsions.
  • Check the label for directions on how to give first aid.
  • Call the Poison Control Center at 1-800-222-1222 for help with first aid information.

The National Pesticide Information Center (NPIC) (1-800-858-7378) can also provide information about pesticide products and their toxicity.


The National Response Center (NRC) is the sole federal point of contact for reporting oil and chemical spills. If you have a spill to report, contact NRC at 1-800-424-8802 (toll-free) or visit their website ( for additional information on reporting requirements and procedures. The NRC can help you decide how to respond to a spill. Producers should be aware that they may be required to report spills to their state Lead Agency (SLA) for pesticide regulation or their state department of environmental protection.

The Comprehensive Environmental Response, Compensations, and Liability Act (CERCLA) requires that all releases of hazardous substances exceeding reportable quantities be reported by the responsible party to the National Response Center (NRC). Title 40 of the Code of Federal Regulations Part 302 promulgates reportable quantities and reporting criteria. All the Extremely Hazardous Chemicals (EHS) that overlap with the CERCLA listed chemicals table (40 CFR Part 302.4) should be reported to NRC as well as to the LEPC and SERC.

For small pesticide spills or for more information, call the pesticide manufacturer or the National Pesticide Information Center (NPIC) at 1-800-858-7378.

More Information

CHEMTREC maintains a large database of Material Safety Data Sheets, chemical information references, resources, and networks of chemical and hazardous material experts who can provide access to technical information regarding chemical products (Emergency call 1-800-424-9300, in the U.S. or 703-741-5500 outside the U.S.).

For more information, contact the National Pesticide Information Center (NPIC) at 1-800-858-7378.