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Biomedical subjects

Michael C R Alavanja

Publications and source records attributed to Michael C R Alavanja.

At least 19 recordsLinked to original sources
PubMed2007

Occupational exposure to organochlorine insecticides and cancer incidence in the Agricultural Health Study.

Organochlorine (OC) insecticides have been regulated as possible human carcinogens primarily on the basis of animal studies. However, the epidemiologic evidence is inconsistent. We investigated the relationship between cancer incidence and OC insecticide use among pesticide applicators enrolled in the Agricultural Health Study, a prospective cohort study of 57,311 licensed applicators in Iowa and North Carolina enrolled between 1993 and 1997. Information on ever use of 7 OC insecticides (aldrin, chlordane, DDT, dieldrin, heptachlor, lindane, toxaphene) was collected from a self-administered questionnaire at enrollment. Lifetime exposure-days to OC insecticides were calculated using additional data from a take-home questionnaire completed by 25,291 participants (44% of total). We found no clear evidence of an association between use of OC insecticides and incident cancers (N = 1,150) ascertained through December, 2002. When we focused on individual insecticides and structurally similar groups (aldrin and dieldrin; chlordane and heptachlor), significantly increased relative risks of some cancers were observed for use of some chemicals (rectal cancer and chlordane, lung cancer and dieldrin, non-Hodgkin lymphoma (NHL) and lindane, melanoma and toxaphene, leukemia and chlordane/heptachlor). Some significant decreased relative risks were also observed (colon cancer and aldrin; overall cancer and heptachlor). In conclusion, we did not observe any clear relationship between cancer risk and the use of OC insecticides. Our chemical-specific findings are based on small numbers and multiple comparisons, and should be interpreted with caution; however, some observed associations (lindane and NHL, chlordane/heptachlor and leukemia) are supported by previous evidence.

Adult↗
PubMed2006

Pesticides and other agricultural factors associated with self-reported farmer's lung among farm residents in the Agricultural Health Study.

BACKGROUND: Farmer's lung, or hypersensitivity pneumonitis, is an important contributor to respiratory morbidity among farmers. METHODS: Using the 1993-7 enrolment data from the Agricultural Health Study, we conducted a cross-sectional study of occupational risk factors for farmer's lung among 50,000 farmers and farm spouses in Iowa and North Carolina using hierarchical logistic regression controlling for age, state, and smoking status. Participants provided information on agricultural exposures, demographic characteristics, and medical history via self-administered questionnaires. Approximately 2% of farmers (n = 481) and 0.2% of spouses (n = 51) reported doctor-diagnosed farmer's lung during their lifetime. We assessed farmers and spouses separately due to different information on occupational exposure history. Only pesticide exposures represented lifetime exposure history, all other farm exposures represented current activities at enrolment. RESULTS: Among farmers, handling silage (OR = 1.41, 95% CI 1.10 to 1.82), high pesticide exposure events (OR = 1.75, 95% CI 1.39 to 2.21), and ever use of organochlorine (OR = 1.34, 95% CI 1.04 to 1.74) and carbamate pesticides (OR = 1.32, 95% CI 1.03 to 1.68) were associated with farmer's lung in mutually-adjusted models. The insecticides DDT, lindane, and aldicarb were positively associated with farmer's lung among farmers. Current animal exposures, while not statistically significant, were positively associated with farmer's lung, particularly for poultry houses (OR = 1.55, 95% CI 0.93 to 2.58) and dairy cattle (OR = 1.28, 95% CI 0.86 to 1.89). The occupational data were more limited for spouses; however, we saw similar associations for dairy cattle (OR = 1.50, 95% CI 0.72 to 3.14) and organochlorine pesticides (OR = 1.29, 95% CI 0.64 to 2.59). CONCLUSION: While historic farm exposures may contribute to the observed associations with pesticides, these results suggest that organochlorine and carbamate pesticides should be further evaluated as potential risk factors for farmer's lung

Adult↗
PubMed2006

Radon, secondhand smoke, glutathione-S-transferase M1 and lung cancer among women.

Tobacco smoke and ionizing radiation induce oxidative stress by transmitting or generating reactive oxygen species (ROS). We hypothesized that glutathione-S-transferase M1 (GSTM1) null homozygotes would have decreased ability to neutralize ROS that might increase their susceptibility to lung cancer. A case-only design was used with lung cancer cases pooled from 3 previously completed case-control studies using archival tissue samples from 270 lung cancer cases to genotype GSTM1. Radon concentrations were measured with long-term alpha-track radon detectors. Secondhand smoke (SHS) was measured with questionnaires and interviews. Unconditional logistic regression was used to calculate the interaction odds ratios (OR) and 95% confidence intervals (95% CI). Radon concentrations >121 Bq m(-3) were associated with a >3-fold interaction OR (OR = 3.41; 95% CI = 1.10, 10.61) for GSTM1 null homozygotes compared to GSTM1 carriers; the linear trend was significant (p trend = 0.03). The SHS and GSTM1 interaction OR was also elevated (OR = 2.28; 95% CI = 1.15-4.51) among never-smokers. This may be the first study to provide evidence of a GSTM1 and radon interaction in risk of lung cancer. Additionally, these findings support the hypothesis that radon and SHS promote neoplasia through shared elements of a common pathway.

Aged↗
PubMed2006

Impaired lung function and lung cancer incidence in a cohort of Swedish construction workers.

BACKGROUND: Although impaired lung function in general has been associated with an increased risk of lung cancer, past studies typically have not attempted to investigate separately the obstructive and restrictive components of respiratory impairment. To deal with this question further, data from a large (n = 176 997) cohort of male Swedish construction workers, for whom spirometry measurements before follow-up were available, were analysed. METHODS: Cancer incidence for 1971-2001 was obtained through linkage with the national cancer registry. Using a modification of the Global Initiative for Chronic Obstructive Lung Disease criteria for chronic obstructive pulmonary disease (COPD), subjects were classified into five categories of lung function: normal, mild COPD, moderate COPD, severe COPD and restrictive lung disease (RLD). Rate ratios (RR) and 95% confidence intervals (CI) for lung cancer across lung function categories were calculated using Poisson regression, adjusted for age and smoking. Other end points (histological types of lung cancer, non-lung tobacco-related cancers, other cancers, total mortality) were also investigated. RESULTS: 834 incident cases of lung cancer were identified. Increased rates of lung cancer were observed for both COPD (mild: RR 1.5, 95% CI 1.2 to 1.9; moderate/severe: RR 2.2, 95% CI 1.8 to 2.7) and RLD (RR 2.0, 95% CI 1.6 to 2.5) relative to normal lung function. These associations did not meaningfully change on applying follow-up lag times of 5, 10 and 15 years after spirometry. When analysed by histological type, associations with both COPD and RLD were stronger for squamous cell carcinoma and small cell carcinoma, and weaker for adenocarcinoma. Both COPD and RLD were associated with increased rates of total mortality. CONCLUSIONS: Obstructive and restrictive impairments in lung function are associated with increased lung cancer risk.

Adult↗
PubMed2006

Cancer incidence among pesticide applicators exposed to metolachlor in the Agricultural Health Study.

Metolachlor is one of the most widely used herbicides in the United States. We evaluated the incidence of cancer among pesticide applicators exposed to metolachlor in the Agricultural Health Study, a prospective cohort study of licensed pesticide applicators in Iowa and North Carolina. A total of 50,193 pesticide applicators were included. Detailed information on pesticide exposure and lifestyle factors was obtained from self-administered enrollment questionnaires completed between 1993 and 1997; average length of follow-up was 7.33 years. Two metolachlor exposure metrics were used : (i) lifetime days personally mixed or applied metolachlor and (ii) intensity-weighted lifetime days (lifetime days x an intensity level). Poisson regression analysis was used to estimate relative risks (RR) and 95% confidence intervals (95%CI) for cancer subtypes by tertiles of metolachlor exposure. No clear risk for any cancer subtype was found for exposure to metolachlor. A significantly decreased RR was found for prostate cancer in the highest category of lifetime days exposure (RR = 0.59; 95%CI, 0.39-0.89) and in the second highest category of intensity-weighted lifetime days exposure (RR = 0.66; 95%CI, 0.45-0.97); however, the test for trend was not significant for either exposure metric. A nonsignificantly increased risk was found for lung cancer with lifetime days exposure in the highest category (RR = 2.37; 95%CI, 0.97-5.82, p-trend = 0.03) but not with intensity-weighted lifetime days. Given the widespread use of metolachlor and the frequent detection of metolachlor in both surface and ground water, future analyses of the AHS will allow further examination of long-term health effects, including lung cancer and the less common cancers.

Acetamides↗
PubMed2006

Pesticides associated with wheeze among commercial pesticide applicators in the Agricultural Health Study.

Pesticides are potential risk factors for respiratory disease among farmers, but farmers are also exposed to other respiratory toxicants. To explore the association of pesticides with wheeze in a population without other farming exposures, the authors analyzed data from 2,255 Iowa commercial pesticide applicators enrolled in the Agricultural Health Study. Controlling for age, smoking status, asthma and atopy history, and body mass index, the authors calculated odds ratios for the relationship between wheeze and 36 individual pesticides participants had used during the year before enrollment (1993-1997). Eight of 16 herbicides were associated with wheeze in single-agent models; however, the risk was almost exclusively associated with the herbicide chlorimuron-ethyl (odds ratio (OR) = 1.62, 95% confidence interval (CI): 1.25, 2.10). Inclusion of chlorimuron-ethyl in models for the other herbicides virtually eliminated the associations. The odds ratios for four organophosphate insecticides (terbufos, fonofos, chlorpyrifos, and phorate) were elevated when these chemicals were modeled individually and remained elevated, though attenuated somewhat, when chlorimuron-ethyl was included. The association for dichlorvos, another organophosphate insecticide, was not attenuated by chlorimuron-ethyl (OR = 2.48, 95% CI: 1.08, 5.66). Dose-response trends were observed for chlorimuron-ethyl, chlorpyrifos, and phorate; the strongest odds ratio was for applying chlorpyrifos on more than 40 days per year (OR = 2.40, 95% CI: 1.24, 4.65). These results add to the emerging literature linking organophosphate insecticides and respiratory health and suggest a role for chlorimuron-ethyl.

Adolescent↗
PubMed2006

Pendimethalin exposure and cancer incidence among pesticide applicators.

BACKGROUND: Pendimethalin, a widely used herbicide, has been classified as a group C possible human carcinogen by the U.S. Environmental Protection Agency. We evaluated the incidence of cancer in relation to reported pendimethelin use among pesticide applicators in the Agricultural Health Study, a prospective cohort of licensed pesticide applicators in Iowa and North Carolina. METHODS: Information on pesticide use came from two questionnaires (enrollment and take-home). The present analysis includes 9089 pendimethalin-exposed and 15,285 nonpendimethalin-exposed pesticide applicators with complete information on pendimethalin use and covariates from a take-home questionnaire. We conducted Poisson regression analyses to evaluate the association of pendimethalin exposure with cancer incidence (mean follow-up = 7.5 years) using two exposure metrics: tertiles of lifetime days of exposure and tertiles of intensity-weighted lifetime days of exposure. RESULTS: Overall cancer incidence did not increase with increasing lifetime pendimethalin use, and there was no clear evidence of an association between pendimethalin use and risks for specific cancers. The risk for rectal cancer rose with increasing lifetime pendimethalin exposure when using nonexposed as the reference (rate ratio = 4.3; 95% confidence interval = 1.5-12.7 for the highest exposed subjects; P for trend = 0.007), but the association was attenuated when using the low exposed as the referent group (P for trend = 0.08). Similar patterns for rectal cancer were observed when using intensity-weighted exposure-days. The number of rectal cancer cases among the pendimethalin-exposed was small (n = 19). There was some evidence for an elevated risk for lung cancer, but the excess occurred only in the highest exposure category for lifetime pendimethalin exposure. The trends for lung cancer risk were inconsistent for different exposure metrics. CONCLUSIONS: We did not find a clear association of lifetime pendimethalin exposure either with overall cancer incidence or with specific cancer sites.

Adult↗
PubMed2006

Depression and pesticide exposures in female spouses of licensed pesticide applicators in the agricultural health study cohort.

OBJECTIVE: This nested case-control study evaluated the association between depression and pesticide exposure among women. METHODS: The study population included 29,074 female spouses of private pesticide applicators enrolled in the Agricultural Health Study between 1993 and 1997. Cases were women who had physician-diagnosed depression requiring medication. Lifetime pesticide use was categorized as never mixed/applied pesticides, low exposure (up to 225 days), high exposure (>225 days), and a history of diagnosed pesticide poisoning. RESULTS: After adjustment for state, age, race, off-farm work, alcohol, cigarette smoking, physician visits, and solvent exposure, depression was significantly associated with a history of pesticide poisoning (odds ratio [OR] = 3.26; 95% confidence interval [CI] = 1.72-6.19) but not low (OR = 1.09; CI = 0.91-1.31) or high (OR = 1.09; 95% CI = 0.91-1.31) cumulative pesticide exposure. CONCLUSION: Pesticide poisoning may contribute to risk of depression.

Adult↗
PubMed2006

Pesticides and adult respiratory outcomes in the agricultural health study.

In the 1700s, Bernardino Ramazzini was among the first to describe respiratory disease among agricultural workers. Since then, farmers continue to have higher rates of respiratory illnesses, even as changes occur in occupational and environmental exposures on farms. While grain and animal exposures have been well studied for their role in agricultural lung diseases, pesticide exposures have not. Using the Agricultural Health Study, a prospective cohort study of approximately 89,000 licensed pesticide applicators and their spouses in Iowa and North Carolina, we are currently assessing the association of pesticides with respiratory outcomes, including wheeze, adult asthma, farmer's lung, and chronic bronchitis. At enrollment (1993-1997), 19% of farmers and 22% of commercial pesticide applicators reported wheeze in the previous year. Using logistic regression models adjusted for age, state, smoking status, and body mass index, we evaluated the association of 40 individual pesticides with wheeze within these two groups separately. In both groups, we observed strong evidence of an association of organophosphates with wheeze. For farmers, the organophosphates chlorpyrifos, malathion, and parathion were positively associated with wheeze; for the commercial applicators, the organophosphates chlorpyrifos, dichlorvos, and phorate were positively associated with wheeze. Chlorpyrifos was strongly associated with wheeze in a dose-dependent manner in both groups; use of chlorpyrifos for at least 20 days per year had an odds ratio of 1.48 (95% confidence interval [CI] = 1.00-2.19) for farmers and 1.96 (95% CI = 1.05-3.66) for commercial applicators. Our wheeze results are consistent with recent animal models that support a role for organophosphates and respiratory outcomes.

Adult↗
PubMed2006

Phorate exposure and incidence of cancer in the agricultural health study.

BACKGROUND: We recently reported a link between use of the organophosphate pesticide phorate and risk of prostate cancer among applicators with a family history of prostate cancer in the Agricultural Health Study (AHS). OBJECTIVE: This finding, together with findings of associations between other organophosphate pesticides and cancer more broadly, prompted us to examine phorate exposure and overall cancer incidence in the AHS. Adding 3 years of follow-up and using more detailed exposure information allowed us to see whether the prostate cancer finding held. METHODS: The AHS is a prospective study of licensed restricted-use pesticide applicators from North Carolina and Iowa. To our knowledge, this is the largest examination of workers occupationally exposed to phorate. Pesticide exposure and other information was collected using two self-administered questionnaires completed from 1993 to 1997. Poisson regression was used to calculate rate ratios (RR) and 95% confidence intervals (CI), adjusting for potential confounders. RESULTS: Phorate use was not related to the incidence of all cancers combined or to any individual cancer, although we had insufficient numbers to study non-Hodgkin lymphoma or leukemia, which have been linked to organophosphates in other studies. Although prostate cancer risk was not significantly related to phorate use overall or among those without a family history, the risk tended to increase among applicators with a family history of prostate cancer. The interaction RR was 1.53 (95% CI, 0.99-2.37). CONCLUSION: The observed statistical interaction suggests a gene-environment interaction between family history and phorate exposure in the incidence of prostate cancer, but other explanations are also possible.

Adult↗
PubMed2006

Cancer incidence among pesticide applicators exposed to cyanazine in the agricultural health study.

BACKGROUND: Cyanazine is a common pesticide used frequently in the United States during the 1980s and 1990s. Animal and human studies have suggested that triazines may be carcinogenic, but results have been mixed. We evaluated cancer incidence in cyanazine-exposed pesticide applicators among the 57,311 licensed pesticide applicators in the Agricultural Health Study (AHS). METHODS: We obtained detailed pesticide exposure information from a self-administered questionnaire completed at enrollment (1993-1997). Cancer incidence was followed through January 2002. Over half of cyanazine-exposed applicators had >or=6 years of exposure at enrollment, and approximately 85% had begun using cyanazine before the 1990s. We used adjusted Poisson regression to calculate rate ratios (RRs) and 95% confidence intervals (CIs) of multiple cancer sites among cyanazine-exposed applicators. We calculated ptrend values, and all statistical tests were two-sided. Two exposure metrics were used: tertiles of lifetime days of exposure (LD) and intensity-weighted LD. RESULTS: A total of 20,824 cancer-free AHS applicators reported ever using cyanazine at enrollment. Cancer incidence comparisons between applicators with the lowest cyanazine exposure and those with the highest exposure yielded the following for the LD metric: all cancers, RR=0.99 (95% CI, 0.80-1.24); prostate cancer, RR=1.23 (95% CI, 0.87-1.70); all lymphohematopoietic cancers, RR=0.92 (95% CI, 0.50-1.72); non-Hodgkin lymphoma, RR=1.25 (95% CI, 0.47-3.35); lung cancer, RR=0.52 (95% CI, 0.22-1.25). CONCLUSIONS: We did not find any clear, consistent associations between cyanazine exposure and any cancer analyzed. The number of sites was small for certain cancers, limiting any conclusion with regard to ovarian, breast, and some other cancers.

Adult↗
PubMed2006

Cancer incidence among pesticide applicators exposed to dicamba in the agricultural health study.

BACKGROUND: Dicamba is an herbicide commonly applied to crops in the United States and abroad. We evaluated cancer incidence among pesticide applicators exposed to dicamba in the Agricultural Health Study, a prospective cohort of licensed pesticide applicators in North Carolina and Iowa. METHODS: Detailed pesticide exposure information was obtained through a self-administered questionnaire completed from 1993 to 1997. Cancer incidence was followed through 31 December 2002 by linkage to state cancer registries. We used Poisson regression to estimate rate ratios and 95% confidence intervals for cancer subtypes by tertiles of dicamba exposure. Two dicamba exposure metrics were used: lifetime exposure days and intensity-weighted lifetime exposure days (lifetime days x intensity score). RESULTS: A total of 41,969 applicators were included in the analysis, and 22,036 (52.5%) reported ever using dicamba. Exposure was not associated with overall cancer incidence nor were there strong associations with any specific type of cancer. When the reference group comprised low-exposed applicators, we observed a positive trend in risk between lifetime exposure days and lung cancer (p = 0.02), but none of the individual point estimates was significantly elevated. We also observed significant trends of increasing risk for colon cancer for both lifetime exposure days and intensity-weighted lifetime days, although these results are largely due to elevated risk at the highest exposure level. There was no apparent risk for non-Hodgkin lymphoma. CONCLUSIONS: Although associations between exposure and lung and colon cancer were observed, we did not find clear evidence for an association between dicamba exposure and cancer risk.

Adult↗
PubMed2006

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. OBJECTIVES: 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.

Adult↗
PubMed2005

Cancer incidence among male pesticide applicators in the Agricultural Health Study cohort exposed to diazinon.

Little is known about the potential carcinogenicity associated with routine application of diazinon, a common organophosphate insecticide. The authors explored a possible association of diazinon exposure with cancer risk in the Agricultural Health Study, a prospective cohort of licensed pesticide applicators in Iowa and North Carolina enrolled in 1993-1997. A total of 23,106 male applicators provided information in a self-administered questionnaire. Among 4,961 applicators who reported using diazinon, 301 incident cancer cases were diagnosed during the follow-up period ending December 2002 compared with 968 cases among 18,145 participants who reported no use. Poisson regression was used to calculate rate ratios and 95% confidence intervals. Two quantitative exposure metrics were used: lifetime exposure days and intensity-weighted lifetime exposure days, a measure that incorporates probability of pesticide exposure with lifetime pesticide application frequency. When lifetime exposure days were used, increased risks for the highest tertile of exposure and significant tests for trend for lung cancer and leukemia were observed. No other cancer site showed an association with diazinon for the highest tertile of exposure. Because these results were based on small numbers, additional analyses are necessary as more cases accrue to clarify whether diazinon is associated with cancer risk in humans.

Adult↗
PubMed2005

Mortality among participants in the agricultural health study.

PURPOSE: This analysis of the Agricultural Health Study cohort assesses the mortality experience of licensed pesticide applicators and their spouses. METHODS: This report is based on 52,393 private applicators (who are mostly farmers) and 32,345 spouses of farmers in Iowa and North Carolina. At enrollment, each pesticide applicator completed a 21-page enrollment questionnaire. Mortality assessment from enrollment (1994-1997) through 2000 provided an average follow-up of about 5.3 years, 447,154 person-years, and 2055 deaths. RESULTS: Compared with the general population in the two states, the cohort experienced a very low mortality rate. Standardized mortality ratios (SMRs) for total mortality, cardiovascular disease, diabetes, COPD, total cancer, and cancers of the esophagus, stomach, and lung were 0.6 or lower for both farmers and spouses. These deficits varied little by farm size, type of crops or livestock on the farm, years of handling pesticides, holding a non-farm job, or length of follow up. SMRs among ever smokers were not as low as among never smokers, but were still less than 1.0 for all smoking-related causes of death. No statistically significant excesses occurred, but slightly elevated SMRs, or those near 1.0, were noted for diseases that have been associated with farming in previous studies. CONCLUSIONS: Several factors may contribute to the low mortality observed in this population, including the healthy worker effect typically seen in cohorts of working populations (which may decline in future years), a short follow-up interval, and a healthier lifestyle manifested through lower cigarette use and an occupation that has traditionally required high levels of physical activity.

Agriculture↗
PubMed2005

Factor analysis of pesticide use patterns among pesticide applicators in the Agricultural Health Study.

Exposure to certain pesticides has been linked with both acute and chronic adverse health outcomes such as neurotoxicity and risk for certain cancers. Univariate analyses of pesticide exposures may not capture the complexity of these exposures since use of various pesticides often occurs simultaneously, and because specific uses have changed over time. Using data from the Agricultural Health Study, a cohort study of 89,658 licensed pesticide applicators and their spouses in Iowa and North Carolina, we employed factor analysis to order to characterize underlying patterns of self-reported exposures to 50 different pesticides. Factor analysis is a statistical method used to explain the relationships between several correlated variables by reducing them to a smaller number of conceptually meaningful, composite variables, known as factors. Three factors emerged for farmer applicators (N=45,074): (1) Iowa agriculture and herbicide use, (2) North Carolina agriculture and use of insecticides, fumigants and fungicides, and (3) older age and use of chlorinated pesticides. The patterns observed for spouses of farmers (N=17,488) were similar to those observed for the farmers themselves, whereas five factors emerged for commercial pesticide applicators (N=4,384): (1) herbicide use, (2) older age and use of chlorinated pesticides, (3) use of fungicides and residential pest treatments, (4) use of animal insecticides, and (5) use of fumigants. Pesticide exposures did not correlate with lifestyle characteristics such as race, smoking status or education. This heterogeneity in exposure patterns may be used to guide etiologic studies of health effects of farmers and other groups exposed to pesticides.

Adult↗