Operator, Bystander & Worker Exposure Studies for Agrochemicals/Biocides

The development, manufacture and use of agrochemicals and biocides may involve risk to human operators. This risk must be assessed in order for chemical products to secure regulatory approval.

When it isn’t possible to make a reasoned argument for exposure level based on data gathered from products already on the market, it is necessary to conduct human exposure studies to provide the necessary data. Such studies must comply with regulatory guidelines like the Organisation for Economic Co-operation and Development (OECD) Guidance Document for the Conduct of Studies of Occupational Exposure to Pesticides During Agricultural Application.

  • Exposure Study Designs
    • Operator exposure
    • Dislodgeable foliar residue (DFR)
    • Spray drift
    • Commodity storage
  • Common Study Components
    • Crop and facility selection
    • Site and season determination
    • Application equipment calibration
    • Choice of operator protective clothing
    • Sampling procedures
    • Meteorological data
    • Analytical procedures for test item

The first step in addressing risk is determining the individual’s level of exposure to the chemical in question. Several factors can impact risk, including a chemical’s formulation type, crop type, manufacturing facility, method and rate of application, and an individual’s involvement.

With over 15 years of experience in conducting numerous exposure studies in various countries, our team of field and analytical professionals has built an impressive track record. Our deep understanding of GLP, GMP, GCP, and GLPf, and scientific expertise supports a variety of exposure studies, including operator exposure, DFR and worker re-entry.

Such investigations are critical, not only to obtain regulatory approval and/or assure compliance, but to develop appropriate safety procedures for those handling chemicals. For example, operator exposure studies evaluate both dermal and inhalation exposure of workers in typical practical field situations (e.g., agricultural workers using knapsack sprayers in orchards or shipyard workers using anti-fouling paints on boats).

We conduct studies throughout Europe, using local country offices to identify and evaluate appropriate operators (e.g., qualified agricultural workers) before a study begins. This allows selection of suitable types of application equipment with representative filling methods and designs, and ensures that study data is representative of commercial practice. We conduct both the field and analytical phases of these studies, including standard clothing and hand wash solutions and the biological monitoring of plasma and urine.

Having worked with active substance submissions and have successfully completed numerous plant protection product authorizations, our regulatory experts can design the right strategy to achieve full registration and authorization for our clients’ products. We are familiar with worldwide regulations and routinely prepare dRRs and AIR3 renewals.

We customize protocols for each study, but all studies comply with appropriate regulatory authorities and follow volunteer consent procedures, health questionnaires and ethics committee review and approval. At times, studies may be reviewed by an independent ethics committee, especially in cases which involve biological monitoring.

We determine operator exposure by chemical analysis of whole body protective suits, inner and outer gloves, hand wash, and urine and blood samples that are collected at appropriate intervals. Inhalation exposure is measured with personal air samplers that collect fractions in an operator’s breathing zones.

Samples are collected, frozen and stored on-site before transport. Samples may be shipped to our own facility for handling by our Residue Analysis group, or directly to clients who wish to perform their own assessment. Our experts can either apply existing residue methods or develop new techniques using the latest and most precise methods of detection.