A MULTIMEDIA, MULTIPLE PATHWAY EXPOSURE ASSESSMENT OF ATRAZINE - FATE, TRANSPORT AND UNCERTAINTY ANALYSIS

The potential danger posed to human health from pesticides and herbici des has been a growing national concern due to the increased frequency of agrochemical residues found in food and water. It is becoming crit ical to determine the concentration in all environmental media for a c omplete picture of potential human exposure. A multimedia transport mo del is used to determine the concentration of atrazine in surface wate r, ground water, surface soil, root zone soil, plants, and air at a ty pical mid-western location. A range of values is used for each model i nput, resulting in a distribution of possible concentrations in each m edium. A sensitivity analysis determines the influence each parameter has on the: outcome variance for each environmental media concentratio n. The concentrations determined for ground and surface water are then compared to measured concentrations in the region to validate the mod el. The concentrations are then compared to measured concentrations in the region to validate the model. A companion paper utilizes these co ncentrations and translates them into human exposure and risk. (C) 199 8 Elsevier Science Ltd.