Exposure to pesticides as a result of their use in agriculture will vary according to the type of formulation, the method of application and the protective measures used. Quantitation of external exposure does not on its own predict the amount absorbed nor does it allow the toxic hazard to be assessed; information on skin penetration is also required. With the use of a suitable generic database for exposure, the assessment of many compounds would only require the measurement of skin penetration. With the knowledge of human dermal pharmacokinetics a field study can be performed which measures the absorbed dose directly and avoids the need for exposure measurement.