Repeat interviews from 4,088 Iowa pesticide applicators participating in the Agricultural Health Study provided the opportunity to evaluate the reliability of self-reported information on pesticide use and various demographic and life-style factors. Self-completed questionnaires were administered 1 year apart when participants returned to county agricultural extension offices for pesticide certification or training. Percentage agreement for ever-/never-use of specific pesticides and application practices was quite high, generally ranging from 70% to more than 90%, and did not vary by age, educational level, or farm size. Agreement was lower (typically 50–60%) for duration, frequency, or decade of first use of specific pesticides. Level of agreement regarding pesticide use in this population is similar to that generally found for factors typically used in epidemiologic studies such as tobacco use and higher than typically reported for diet, physical activity, and medical conditions.

This paper reviews epidemiologic studies of cancer among agricultural populations to identify possible associations and to provide a focus for future investigations. Meta-analyses of mortality surveys of farmers find excesses of several cancers, including connective tissue, non-Hodgkin's lymphoma, Hodgkin's disease, multiple myeloma and cancers of the skin, stomach, and brain, and deficits for total mortality, heart disease, total cancer, and cancers of the esophagus, colon, lung, and bladder. Meta-analyses of studies of individual cancers also support these findings, indicating a need to identify exposures and lifestyle factors that might account for this mortality pattern. Although cancer studies of other occupations that might have pesticide exposures in common with farmers show some similarities with observations among farmers, the overall patterns are quite different. This suggests that pesticides are not likely to fully explain the cancer and other disease patterns observed among farmers. Because exposures vary by type of farm operation, exposures for individual farmers can differ considerably. Studies in the future need to focus on the full range of exposures to fully understand the cancer pattern in farmers.

Objective: This study describes associations of ozone and fine particulate matter with Parkinson's disease observed among farmers in North Carolina and Iowa. Methods: We used logistic regression to determine the associations of these pollutants with self-reported, doctor-diagnosed Parkinson's disease. Daily predicted pollutant concentrations were used to derive surrogates of long-term exposure and link them to study participants' geocoded addresses. Results: We observed positive associations of Parkinson's disease with ozone (odds ratio = 1.39; 95% CI: 0.98 to 1.98) and fine particulate matter (odds ratio = 1.34; 95% CI: 0.93 to 1.93) in North Carolina but not in Iowa. Conclusions: The plausibility of an effect of ambient concentrations of these pollutants on Parkinson's disease risk is supported by experimental data demonstrating damage to dopaminergic neurons at relevant concentrations. Additional studies are needed to address uncertainties related to confounding and to examine temporal aspects of the associations we observed.

Background: The mortality experience of 4702 (4413 men and 289 women) civilian workers in a US Coast Guard shipyard was evaluated. Methods: All workers employed at the shipyard between 1 January 1950 and 31 December 1964 were included in the study and were followed through 31 December 2001 for vital status. Detailed shipyard and lifetime work histories found in the shipyard personnel records and job descriptions were evaluated. Workers were classified as likely exposed to any potential hazardous substances. In addition, 20 job groups were created on likely similar exposures. Standardised mortality ratios (SMRs) were calculated based on the general population of the state and adjusted for age, calendar period, sex and race. Results: The follow-up was successful for 93.3% of the workers. Among all men employed in the shipyard, there was an excess of mortality from all causes of death (SMR 1.08; 95% CI 1.04 to 1.12), respiratory cancers (SMR 1.29; 95% CI 1.15 to 1.43), lung cancer (SMR 1.26; 95% CI 1.12 to 1.41), mesothelioma (SMR 5.07; 95% CI 1.85 to 11.03) and emphysema (SMR 1.44; 95% CI 1.01 to 1.99) and a decrease for cardiovascular diseases (OR 0.95; 95% CI 0.90 to 1.00), vascular lesions of the central nervous system (SMR 0.80; 95% CI 0.67 to 0.96), cirrhosis of the liver (SMR 0.38; 95% CI 0.25 to 0.57) and external causes of death (SMR 0.55; 95% CI 0.44 to 0.68). A similar pattern was observed for the men classified as exposed. No increasing trend of mortality was found with duration of employment in the shipyard, with the exception of mesothelioma (SMRs of 4.23 and 6.27 for <10 years and ⩾10 years, respectively). In occupations with at least three cases and with an SMR of ⩾1.3, the authors observed a significantly elevated mortality for lung cancer among machinists (SMR 1.60; 95% CI 1.08 to 2.29) and shipfitters, welders and cutters (SMR 1.34; 95% CI 1.07 to 1.65) and for oral and nasopharyngeal cancers among wood workers (SMR 6.20; 95% CI 2.27 to 13.50). Conclusion: Employment in this Coast Guard shipyard revealed a small but significant excess mortality from all causes, lung cancer and mesothelioma, most of which is probably related to asbestos exposure.