Fonofos exposure and cancer incidence in the agricultural health study.
BACKGROUND
The Agricultural Health Study (AHS) is a prospective cohort study of licensed pesticide applicators from Iowa and North Carolina enrolled 1993-1997 and followed for incident cancer through 2002. A previous investigation in this cohort linked exposure to the organophosphate fonofos with incident prostate cancer in subjects with family history of prostate cancer.


OBJECTIVE
This finding along with findings of associations between organophosphate pesticides and cancer more broadly led to this study of fonofos and risk of any cancers among 45,372 pesticide applicators enrolled in the AHS.


METHODS
Pesticide exposure and other data were collected using self-administered questionnaires. Poisson regression was used to calculate rate ratios (RRs) and 95% confidence intervals (CIs) while controlling for potential confounders.


RESULTS
Relative to the unexposed, leukemia risk was elevated in the highest category of lifetime (RR = 2.24; 95% CI, 0.94-5.34, Ptrend = 0.07) and intensity-weighted exposure-days (RR = 2.67; 95% CI, 1.06-6.70, Ptrend = 0.04), a measure that takes into account factors that modify pesticide exposure. Although prostate cancer risk was unrelated to fonofos use overall, among applicators with a family history of prostate cancer, we observed a significant dose-response trend for lifetime exposure-days (Ptrend = 0.02, RR highest tertile vs. unexposed = 1.77, 95% CI, 1.03-3.05; RRinteraction = 1.28, 95% CI, 1.07-1.54). Intensity-weighted results were similar. No associations were observed with other examined cancer sites.


CONCLUSIONS
Further study is warranted to confirm findings with respect to leukemia and determine whether genetic susceptibility modifies prostate cancer risk from pesticide exposure.
Mahajan
Rajeev
R
Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, Maryland 20852, USA.
Blair
Aaron
A
Lynch
Charles F
CF
Schroeder
Paul
P
Hoppin
Jane A
JA
Sandler
Dale P
DP
Alavanja
Michael C R
MC
D000328:Adult; D000382:Agricultural Workers' Diseases / Q000139:chemically induced / Q000453:epidemiology; D000383:Agriculture; D015331:Cohort Studies; D005192:Family Health; D005260:Female; D004397:Fonofos / Q000032:analysis / Q000506:poisoning*; D006801:Humans; D015994:Incidence; D007484:Iowa / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000139:chemically induced* / Q000453:epidemiology / Q000235:genetics; D009657:North Carolina / Q000453:epidemiology; D016273:Occupational Exposure / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D062025:Organophosphate Poisoning; D009943:Organophosphorus Compounds / Q000032:analysis; D009946:Organothiophosphorus Compounds / Q000032:analysis / Q000506:poisoning; D010575:Pesticides / Q000032:analysis / Q000506:poisoning; D016012:Poisson Distribution; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000235:genetics; D012044:Regression Analysis; D012307:Risk Factors; D011795:Surveys and Questionnaires
D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D010575:Pesticides; D004397:Fonofos