Fluorescent Tracer: An Educational Tool for Pesticide Safety Educators


For many agricultural workers and their families, pesticide exposure is a serious concern. Each year, as many as 25 million agricultural workers in developing countries may suffer from unintentional acute pesticide poisonings1. In the United States, the US Environmental Protection Agency estimates that around 10,000 to 20,000 agricultural-related poisoning cases are reported annually. The majority of agricultural pesticide poisoning and injury incidents happen through skin exposure and absorption. Skin exposure occurs when an agricultural pesticide handler mixes and applies pesticides, or comes into contact with pesticide residues on contaminated surfaces, such as unwashed application equipment, or dirty personal protective equipment (PPE).

Using personal protective equipment is extremely important, but it does not provide a guarantee that a pesticide handler will be fully protected from chemical exposure. To test the protectiveness of certain types of PPE in field conditions, Dr. Richard Fenske pioneered the use of the fluorescent tracer technique in the early 1980s as a way to measure pesticide contamination on the skin of agricultural pesticide handlers. When Dr. Fenske studied handlers who used high-volume airblast sprayers in a California citrus grove, the fluorescent tracer technique showed that the pesticide could penetrate the PPE and get under it through openings like the neck2. For more than 20 years, the studies of Dr. Fenske and other scientists using the fluorescent tracer technique have revealed that pesticide contamination on the skin is largely unrecognized and is influenced by many possible factors such as:

  • Characteristics of pesticides
  • Type of protective clothing
  • Environmental conditions
  • Culture of the workplace
  • Methods of mixing and application
  • Knowledge and practices of individual pesticide handlers

Researchers recognized early on that the fluorescent tracer technique is also a compelling way to teach agricultural pesticide handlers, managers, farming communities, and other trainers about pesticide exposure. Fluorescent tracers have been used in pesticide safety projects in the US, Canada, Europe, Ecuador, Nicaragua, Cambodia, and Mali. Recently, the Washington State Department of Agriculture has used tracers in their Hands-on Handler Training. As an educational tool, the fluorescent tracer technique can enhance learning, stimulate discussion, and promote safe practices. Most participants will be surprised to see the extent of contamination on themselves or on others. This can leave a lasting impression and motivate workers to protect themselves from pesticide exposure. Seeing skin contamination can help people understand where, how, and why pesticide exposure occurs. With new knowledge, participants can take appropriate steps to minimize pesticide exposure.

The Fluorescent Tracer Technique

The Fluorescent Tracer (FT) Technique was developed for pesticide applicator safety education, training, and self-evaluation. It was designed for pesticide safety educators, including agricultural extension agents, integrated pest management trainers, farm supervisors, safety managers, and anyone interested in teaching safe farming practices. The technique is a powerful tool for showing pesticide contamination and for helping workers evaluate their practices and protective equipment. Quick demos and hands-on activities make learning fun and memorable - seeing is believing!

What is Fluorescent Tracer?

Fluorescent tracer is a non-toxic chemical used to mimic pesticide contamination on skin, clothing, and surfaces. Under normal lighting, when mixed, diluted and applied (like pesticides) it cannot be seen. Under a blacklight tracer is visible and can reveal areas of potential exposure.

How can I obtain an FT kit?

To purchase a kit or to order a kit on loan, contact us at pnash@u.washington.edu, or call (800) 330-0827. For additional information visit http://depts.washington.edu/pnash/FT.php

Flourescent Tracer Manual

Download English manual (pdf)
Download Spanish manual (pdf)


Fluorescent Tracer Training Video

1Jeyaratnam, J. (1990). Acute Pesticide Poisoning: A Major Global Health Problem. World Health Statistics Quarterly 43(3):139-44.
2Fenske, R. (1988). Comparative assessment of protective clothing performance by measurement of dermal exposure during pesticide applications. Appl Ind Hyg 3:207-213

©2009, Pacific Northwest Agricultural Safety and Health (PNASH) Center

(206) 616-1958, (800) 330-0827, pnash@u.washington.edu Department of Environmental and Occupational Health Sciences School of Public Health, University of Washington Box 357234, Seattle, WA 98195-7234

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