RISK-FACTORS FOR SYSTEMIC ILLNESSES FOLLOWING AGRICULTURAL EXPOSURES TO RESTRICTED ORGANOPHOSPHATES IN CALIFORNIA, 1984-1988

Organophosphate (OP)-related systemic illnesses reported to the Worker Health and Safety (WH&S) Branch, and restricted OF-related agricultur al use data reported to the Information Services Branch at the Califor nia Department of Food and Agriculture (CDFA) (now CAL-EPA) during 198 4-1988 were used to assess factors associated with OP-related systemic illnesses. Counts of OF-related systemic illnesses (numerator), relat ive to OF-related use data (denominator), such as pounds applied, numb er of applications, and acres treated (pounds applied/acres treated), were analyzed by crop treated, season of application, method of applic ation, geographic region, and by specific OP applied. A Relative Illne ss/Use Ratio (RIUR) was calculated by Poisson regression. The highest risk of systemic illness was associated with OP applications to fleshy fruit (mainly fruit trees) compared to all other crops combined (RIUR = 2.9, 95%CI = 2.2-3.9) using pounds applied in the denominator; foll owed by vegetables and melons (RIUR = 1.9, 95%CI = 1.4-2.4). Air appli cations resulted in higher RIURs for systemic illness than did ground applications (RIUR = 2.1, 95%CI = 1.7-2.5). Specific OPs that showed s ignificantly elevated RIURs for systemic illness when compared to othe r OPs were Mevinphos (RIUR = 5.8, 95%CI = 5.0-6.8), Demeton (RIUR = 4. 3, 95%CI = 2.6-7.1), Oxydemeton-Methyl (RIUR = 3.8, 95%CI = 3.0-4.9), Methamidophos (RIUR = 1.6, 95%CI = 1.2-2.0) and Azinphos-Methyl (RIUR = 1.3, 95%CI = 1.1-1.6). (C) 1997 Wiley-Liss, Inc.