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Agricultural Health Study (agricultural + health_study)
Selected AbstractsCarbaryl exposure and incident cancer in the Agricultural Health StudyINTERNATIONAL JOURNAL OF CANCER, Issue 8 2007Rajeev Mahajan Abstract Carbaryl is a carbamate insecticide with a broad spectrum of uses in agricultural, commercial and household settings. It has previously been linked with non-Hodgkin lymphoma (NHL) but studies of cancer risk in humans are limited. We examined occupational carbaryl use and risk of all cancers in the Agricultural Health Study, a prospective study of a cohort of pesticide applicators in North Carolina and Iowa. This analysis included 21,416 subjects (1,291 cases) enrolled from 1993,1997 and followed for cancer incidence through 2003. 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. Carbaryl was not associated with cancer risk overall. Relative to subjects who never used carbaryl, melanoma risk was elevated with >175 lifetime exposure-days (RR = 4.11; 95%CI, 1.33,12.75; p -trend = 0.07), >10 years of use (RR = 3.19; 95%CI, 1.28,7.92; p -trend = 0.04), or ,10 days of use per year (RR = 5.50; 95%CI, 2.19,13.84; p -trend < 0.001). Risk remained after adjusting for sunlight exposure. Although not significant, there appeared to be a trend of decreasing prostate cancer risk with increasing level of exposure. A small increase in NHL risk was observed using some, but not all, exposure measures. No associations were observed with other examined cancer sites. Because the observed results were not hypothesized a priori and because of limited study of their biological plausibility, they should be interpreted with caution. © 2007 Wiley-Liss, Inc. [source] Pesticide use and colorectal cancer risk in the agricultural health studyINTERNATIONAL JOURNAL OF CANCER, Issue 2 2007Won Jin Lee Abstract We investigated the relationship between agricultural pesticides and colorectal cancer incidence in the Agricultural Health Study. A total of 56,813 pesticide applicators with no prior history of colorectal cancer were included in this analysis. Detailed pesticide exposure and other information were obtained from self-administered questionnaires completed at the time of enrollment (1993,1997). Cancer incidence was determined through population-based cancer registries from enrollment through December 31, 2002. A total of 305 incident colorectal cancers (212 colon, 93 rectum) were diagnosed during the study period, 1993,2002. Although most of the 50 pesticides studied were not associated with colorectal cancer risk, chlorpyrifos use showed significant exposure response trend (p for trend = 0.008) for rectal cancer, rising to a 2.7-fold (95% confidence interval: 1.2,6.4) increased risk in the highest exposure category. Aldicarb was associated with a significantly increased risk of colon cancer (p for trend = 0.001), based on a small number of exposed cases, with the highest exposure category resulting in a 4.1-fold increased risk (95% confidence interval: 1.3,12.8). In contrast, dichlorophenoxyacetic acid showed a significant inverse association with colon cancer but the association was not monotonic. Our findings should be interpreted cautiously since the literature suggesting that pesticides are related to colorectal cancer is limited. Nonetheless the possibility of an association between exposure to certain pesticides and incidence of colorectal cancer among pesticide applicators deserves further evaluation. © 2007 Wiley-Liss, Inc. [source] Effects of self-reported health conditions and pesticide exposures on probability of follow-up in a prospective cohort studyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 5 2010Martha P. Montgomery MHS Abstract Background We investigated the potential for selection bias due to non-participation in the follow-up of a large prospective cohort study. Methods Licensed pesticide applicators (52,395 private; 4,916 commercial) in the Agricultural Health Study provided demographic, health, and pesticide exposure information at enrollment (1993,1997) and in a 5-year follow-up telephone interview. Factors associated with non-participation in the follow-up were identified using multiple logistic regression. Potential for selection bias was evaluated by comparing exposure,disease associations between the entire cohort and the follow-up subset. Results Sixty-six percent of private and 60% of commercial applicators completed the follow-up interview. Private and commercial applicators who did not complete the follow-up reported at enrollment younger age, less education, lower body mass index, poorer health behaviors but fewer health conditions, and lower pesticide use. Estimates of exposure,disease associations calculated with and without non-participants did not indicate strong selection bias. Conclusions Differences between non-participants and participants in the follow-up interview were generally small, and we did not find significant evidence of selection bias. However, the extent of bias may depend on the specific exposure and outcome under study. Am. J. Ind. Med. 53:486,496, 2010. © 2009 Wiley-Liss, Inc. [source] Nested case-control analysis of high pesticide exposure events from the Agricultural Health StudyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2001Michael C. R. Alavanja Abstract Background A nested case-control analysis of high pesticide exposure events (HPEEs) was conducted using the Iowa farmers enrolled in the Agricultural Health Study (AHS). Methods In the 12 months of the study, 36 of the 5,970 farmer applicators randomly chosen from the AHS cohort (six per 1,000 farmer applicators per year) met our definition of an HPEE, by reporting "an incident with fertilizers, weed killers, or other pesticides that caused an unusually high personal exposure" resulting in physical symptoms or a visit to a health care provider or hospital. Eligibility criteria were met by 25 HPEE cases and 603 randomly selected controls. Results Significant risk factors for an HPEE included: poor financial condition of the farm which limited the purchase of rollover protective structures OR,=,4.6 (1.5,16.6), and having a high score on a risk acceptance scale OR,=,3.8 (1.4,11.2). Other non-significant factors were also identified. Conclusions The limited statistical power of this study necessitates replication of these analyses with a larger sample. Nonetheless, the observed elevated odds ratios of an HPEE provide hypotheses for future studies that may lead to preventive action. Am. J. Ind. Med. 39:557,563, 2001. © 2001 Wiley-Liss, Inc. [source] Pesticide use and colorectal cancer risk in the agricultural health studyINTERNATIONAL JOURNAL OF CANCER, Issue 2 2007Won Jin Lee Abstract We investigated the relationship between agricultural pesticides and colorectal cancer incidence in the Agricultural Health Study. A total of 56,813 pesticide applicators with no prior history of colorectal cancer were included in this analysis. Detailed pesticide exposure and other information were obtained from self-administered questionnaires completed at the time of enrollment (1993,1997). Cancer incidence was determined through population-based cancer registries from enrollment through December 31, 2002. A total of 305 incident colorectal cancers (212 colon, 93 rectum) were diagnosed during the study period, 1993,2002. Although most of the 50 pesticides studied were not associated with colorectal cancer risk, chlorpyrifos use showed significant exposure response trend (p for trend = 0.008) for rectal cancer, rising to a 2.7-fold (95% confidence interval: 1.2,6.4) increased risk in the highest exposure category. Aldicarb was associated with a significantly increased risk of colon cancer (p for trend = 0.001), based on a small number of exposed cases, with the highest exposure category resulting in a 4.1-fold increased risk (95% confidence interval: 1.3,12.8). In contrast, dichlorophenoxyacetic acid showed a significant inverse association with colon cancer but the association was not monotonic. Our findings should be interpreted cautiously since the literature suggesting that pesticides are related to colorectal cancer is limited. Nonetheless the possibility of an association between exposure to certain pesticides and incidence of colorectal cancer among pesticide applicators deserves further evaluation. © 2007 Wiley-Liss, Inc. [source] | ||||||||||