A walkthrough survey was conducted at Soilserve (SIC-2879), Salinas, California on May 5 and 6, 1977, to observe the pesticide formulation process at a pesticide factory. Approximately 85, including chlorinated hydrocarbons, carbamates, and herbicides, were formulated at this factory. Production was not constant and varied according to season and demand. There were 140 people employed, including 8 formulators and 85 applicators. All employees received preemployment physical examinations. Baseline cholinesterase concentrations were established for each employee by blood samples that were drawn on the first day of employment. Blood samples were collected again 73 hours later, and then on a regular monthly basis. In general, a gradual decline of blood cholinesterase concentrations was noted as production increased. Liquid compounds were formulated within closed systems. Solid compounds were dispensed in three forms: pellets, powder, or granulated substances. Raw materials were mixed in open ended drums and were added to the drum by hand. There was no exhaust ventilation for any of the liquid or solid mixing operations, nor on the dispensing apparatus. However, both liquid and solid formulations were done outside. The pesticides were applied in the fields by tractor, plane, or helicopter. Most applications were done at night. A closed system was developed for the transfer of the pesticides, and respirators were provided.
Industry-wide Studies Branch, NIOSH, Industrial Hygiene Report No. IWS-80-10, 2 pages