Reported residential pesticide use and breast cancer risk on Long Island, New York

Pesticides, common environmental exposures, have been examined in relation to breast cancer primarily in occupational studies or exposure biomarker studies. No known studies have focused on self-reported residential pesticide use. The authors investigated the association between reported lifetime residential pesticide use and breast cancer risk among women living on Long Island, New York. They conducted a population-based case-control study of 1,508 women newly diagnosed with breast cancer between August 1996 and July 1997 and 1,556 randomly selected, age-frequency-matched controls. Comprehensive residential pesticide use and other risk factors were assessed by using an in-person, interviewer-administered questionnaire. Unconditional logistic regression was used to calculate odds ratios and 95% confidence intervals. Breast cancer risk was associated with ever lifetime residential pesticide use (odds ratio = 1.39, 95% confidence interval: 1.15, 1.68). However, there was no evidence of increasing risk with increasing lifetime applications. Lawn and garden pesticide use was associated with breast cancer risk, but there was no dose response. Little or no association was found for nuisance-pest pesticides, insect repellents, or products to control lice or fleas and ticks on pets. This study is the first known to suggest that self-reported use of residential pesticides may increase breast cancer risk. Further investigation in other populations is necessary to confirm these findings.     

Lifetime Pesticide Use and Telomere Shortening among Male Pesticide Applicators in the Agricultural Health Study

Background: Telomere length (TL) in surrogate tissues may be influenced by environmental exposures.Objective: We aimed to determine whether lifetime pesticides use is associated with buccal cell TL.Methods: We examined buccal cell TL in relation to lifetime use of 48 pesticides for 1,234 cancer-free white male pesticide applicators in the Agricultural Health Study (AHS), a prospective cohort study of 57,310 licensed pesticide applicators. Participants provided detailed information on lifetime use of 50 pesticides at enrollment (1993–1997). Buccal cells were collected from 1999 to 2006. Relative telomere length (RTL) was measured using quantitative real-time polymerase chain reaction. We used linear regression modeling to evaluate the associations between specific pesticides and the logarithm of RTL, adjusting for age at buccal cell collection, state of residence, applicator license type, chewing tobacco use, and total lifetime days of all pesticide use.Results: The mean RTL for participants decreased significantly in association with increased lifetime days of pesticide use for alachlor (p = 0.002), 2,4-dichlorophenoxyacetic acid (2,4-D; p = 0.004), metolachlor (p = 0.01), trifluralin (p = 0.05), permethrin (for animal application) (p = 0.02), and toxaphene (p = 0.04). A similar pattern of RTL shortening was observed with the metric lifetime intensity-weighted days of pesticide use. For dichlorodiphenyltrichloroethane (DDT), we observed significant RTL shortening for lifetime intensity-weighted days (p = 0.04), but not for lifetime days of DDT use (p = 0.08). No significant RTL lengthening was observed for any pesticide.Conclusion: Seven pesticides previously associated with cancer risk in the epidemiologic literature were inversely associated with RTL in buccal cell DNA among cancer-free pesticide applicators. Replication of these findings is needed because we cannot rule out chance or fully rule out bias.     

Soy,Soy Isoflavones,and Protein Intake in Relation to Mortality from All Causes,Cancers, and Cardiovascular Diseases: A Systematic Review and Dose–Response Meta-Analysis of Prospective Cohort Studies

ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I² value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I²=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I²=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.     

#51 Pesticides in carpet dust and self-reported pesticide use in four areas of the us

PURPOSE: As part of a case-control study of non-Hodgkin's lymphoma (NHL), exposure to home/garden pesticides is being assessed based on self-reported pest treatments and analysis of carpet dust samples. Here, we compare the study centers in terms of reported pesticide use and pesticide levels in carpet dust sampled from control subjects' current homes.METHODS: Of 1,057 controls, 53 refused dust collection (5%). About half of those who consented were eligible (owned carpets 5 years and used vacuum cleaner within past year) (530 subjects). Southwest Research Institute sieved and extracted dust from a used vacuum cleaner bag collected from each subject's current home. For 513 samples with sufficient dust (78 in Detroit, 147 in Iowa, 127 in Los Angeles, and 161 in Seattle), analysis for 30 pesticides was performed by GC/MS.RESULTS: In LA, 85% of subjects treated for crawling insects in/around the home (excluding lawns/gardens), higher than any other site. Dust from LA had the highest median levels of propoxur, chlorpyrifos, diazinon, and permethrin, insecticides often used for crawling insects. Termite treatments were most prevalent in LA, consistent with LA's relatively high median levels of chlorpyrifos, permethrin, and chlordane. Although lawn/garden insects were treated most often in Seattle (61%), none of the lawn/garden insecticides analyzed were detected most frequently in Seattle. The herbicides 2,4-D and dicamba were highest in Iowa, which had the highest reported treatment of lawn/garden weeds (69%). The agricultural herbicides atrazine, alachlor, and metolachlor were detected only in Iowa.CONCLUSION: Dust levels of residential pesticides were generally reflective of self-reported pest treatment practices. Seattle's relatively low prevalence of lawn/garden insecticides in dust, despite high reported use of these pesticides, is perhaps related to the relatively moist climate in Seattle.     

The Effects of Soy Consumption before Diagnosis on Breast Cancer Survival: The Multiethnic Cohort Study

This study tested the hypothesis that prediagnostic soy intake was inversely associated with all-cause and breast cancer-specific mortality. The analyses included 3842 women in the Multiethnic Cohort (MEC) study of African Americans, Native Hawaiians, Japanese Americans, Latinos, and Caucasians, who completed a quantitative food frequency questionnaire, aged ≥50 yr at cohort entry, and diagnosed with primary invasive breast cancer following cohort entry (1993–2007). Hazard ratios (HR) and 95% confidence intervals (CI) were estimated from Cox proportional hazards regression with adjustment for known clinical and lifestyle factors. During a mean follow-up after diagnosis of invasive breast cancer of 6.2 ± 3.8 yr, there were 804 deaths including 376 breast cancer-specific deaths. The HR (95%CI) for all-cause and breast cancer-specific morality comparing the highest versus lowest tertiles were 1.03 (0.81–1.33) and 1.03 (0.71–1.50) for soy products and 0.99 (0.82–1.20) and 0.95 (0.71–1.28) for total isoflavones, respectively (P_trend > 0.60 for all). There was limited evidence of differences by hormone receptor status, tumor stage, or ethnic group. Prediagnostic soy intake was unrelated to mortality in postmenopausal women. Our findings are consistent with the literature that soy consumption does not adversely affect breast cancer survival in women.     

Association between physical activity and mortality in breast cancer: a meta-analysis of cohort studies

Previous studies concerning the association between physical activity (PA) and mortality in breast cancer yielded mixed results. We investigated the association by performing a meta-analysis of all available studies. Relevant studies were identified by searching PubMed and EMBASE to January 2014. We calculated the summary relative risk (RR) and 95 % confidence intervals (CIs) using random-effects models. The dose–response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression. Sixteen cohort studies involving 42,602 patients of breast cancer were selected for meta-analysis. The analyses showed that patients who participated in any amount of PA before diagnosis had a RR of 0.82 (95 % CI 0.74–0.91) for breast cancer-specific mortality (vs. low PA). Those who participated in high PA and moderate PA before diagnosis had a RR of breast cancer-specific mortality of 0.81 (95 % CI 0.72–0.90) and 0.83 (95 % CI 0.73–0.94), respectively. Similar inverse associations of prediagnosis PA were found for all-cause mortality. Postdiagnosis PA on breast cancer-specific and all-cause mortality also showed the same results. Stratifying by body mass index (<25 vs. ≥25) or menopausal status, all the subgroups experienced benefits with PA, with a stronger mortality reduction among overweight women than normal weight women and among postmenopausal women than premenopausal women. A linear and significant dose–response association was only found for breast cancer-specific or all-cause mortality and prediagnosis PA (P for nonlinearity = 0.07 and 0.10, respectively). In conclusion, both prediagnosis and postdiagnosis PA were associated with reduced breast cancer-specific mortality and all-cause mortality.     

Active and passive cigarette smoke and breast cancer survival

PURPOSE: The association between active and passive cigarette smoking before breast cancer diagnosis and survival was investigated among a cohort of invasive breast cancer cases (n = 1273) participating in a population-based case-control study. METHODS: Participants diagnosed with a first primary breast cancer between August 1, 1996, and July 31, 1997, were followed-up until December 31, 2002, for all-cause mortality (n = 188 deaths), including breast cancer-specific mortality (n = 111), as reported to the National Death Index. RESULTS: In Cox models, the adjusted hazards ratios (HRs) for all-cause mortality were slightly higher among current and former active smokers, compared with never smokers (HR, 1.23; 95% confidence interval [95% CI], 0.83-1.84) and 1.19 (95% CI, 0.85-1.66), respectively). No association was found between active or passive smoking and breast cancer-specific mortality. All-cause and breast cancer-specific mortality was higher among active smokers who were postmenopausal (HR, 1.64; 95% CI, 1.03-2.60 and HR, 1.45; 95% CI, 0.78-2.70, respectively) or obese at diagnosis (HR, 2.10; 95% CI, 1.03-4.27 and HR, 1.97; 95% CI, 0.89-4.36, respectively). Associations between smoking and all-cause and breast cancer-specific mortality did not differ by cancer treatment. CONCLUSIONS: These data do not provide strong evidence for an association between smoking and all-cause or breast cancer-specific mortality, although smokers who are postmenopausal or obese at diagnosis may be at higher risk.     

Association Between Sugar-Sweetened Beverage Intake and Mortality Risk in Women: The California Teachers Study

BackgroundThe evidence linking sugar-sweetened beverage (SSB) intake and mortality risk is conflicting, and associations between various SSB subtypes and mortality remain unclear.ObjectiveTo examine the association between baseline SSB intake, subtypes of SSB intake, and mortality risk in women.DesignProspective cohort study.Participants/settingParticipants of the California Teachers Study (n = 100,314; median age = 53 years) free of cardiovascular disease, cancer, and diabetes at baseline (1995-1996) were followed from 1995 to 2015. Baseline SSB intake was defined as caloric soft drinks (regular soft drinks, not diet soda), sweetened bottled waters or teas, and fruit drinks; and was derived from a self-administered food frequency questionnaire.Main outcome measureMortality was ascertained via annual linkage with state- and nationwide mortality records and the National Death Index over 20 years.Statistical analysisMultivariable-adjusted Cox proportional hazards models were used to generate hazard ratios (HRs) and 95% CIs for assessing associations between SSB intake and mortality. Rare/never consumers were the comparator group.ResultsThere were a total of 14,143 deaths over 20 years (30.5% from cardiovascular disease; 29.2% from cancer). In women who consumed ≥ 7 servings/week of SSBs at baseline (4% of participants), the multivariable-adjusted HRs were not significant for all-cause, cardiovascular disease-specific, or cancer-specific mortality. Consuming ≥ 7 servings/week of baseline caloric soft drink was associated with a higher risk of all-cause (HR = 1.26, 95% CI 1.10 to 1.46; P for trend = 0.02) and cancer-specific (HR = 1.33, 95% CI 1.08 to 1.63; P for trend = 0.08) mortality. In secondary analyses, consuming ≥ 1.5 c/day of baseline SSBs was associated with all-cause mortality (HR = 1.12, 95% CI 1.02 to 1.24; P for trend = 0.01).ConclusionsAlthough the baseline frequency of total SSB intake was not significantly associated with mortality, consuming ≥ 7 servings/week of caloric soft drinks was associated with higher risk of all-cause and cancer-specific mortality. Findings support public health efforts to reduce caloric soft drink consumption.     

Dietary Intake of Advanced Glycation End Products (AGEs) and Mortality among Individuals with Colorectal Cancer

Advanced glycation end-products (AGEs) may promote oxidative stress and inflammation and have been linked to multiple chronic diseases, including cancer. However, the association of AGEs with mortality after colorectal cancer (CRC) diagnosis has not been previously investigated. Multivariable Cox proportional hazards models were used to calculate hazard ratios and corresponding 95% confidence intervals for associations between dietary intake of AGEs with CRC-specific and all-cause mortality among 5801 participant cases diagnosed with CRC in the European Prospective Investigation into Cancer and Nutrition study between 1993 and 2013. Dietary intakes of AGEs were estimated using country-specific dietary questionnaires, linked to an AGE database, that accounted for food preparation and processing. During a median of 58 months of follow-up, 2421 cases died (1841 from CRC). Individually or combined, dietary intakes of AGEs were not associated with all-cause and CRC-specific mortality among cases. However, there was a suggestion for a positive association between AGEs and all-cause or CRC-specific mortality among CRC cases without type II diabetes (all-cause, P_interaction = 0.05) and CRC cases with the longest follow-up between recruitment and cancer diagnosis (CRC-specific, P_interaction = 0.003; all-cause, P_interaction = 0.01). Our study suggests that pre-diagnostic dietary intakes of AGEs were not associated with CRC-specific or all-cause mortality among CRC patients. Further investigations using biomarkers of AGEs and stratifying by sex, diabetes status, and timing of exposure to AGEs are warranted.     

Residential proximity to agricultural pesticide applications and childhood acute lymphoblastic leukemia

Ambient exposure from residential proximity to applications of agricultural pesticides may contribute to the risk of childhood acute lymphoblastic leukemia (ALL). Using residential histories collected from the families of 213 ALL cases and 268 matched controls enrolled in the Northern California Childhood Leukemia Study, the authors assessed residential proximity within a half-mile (804.5 m) of pesticide applications by linking address histories with reports of agricultural pesticide use. Proximity was ascertained during different time windows of exposure, including the first year of life and the child's lifetime through the date of diagnosis for cases or reference for controls. Agricultural pesticides were categorized a priori into groups based on similarities in toxicological effects, physicochemical properties, and target pests or uses. The effects of moderate and high exposure for each group of pesticides were estimated using conditional logistic regression. Elevated ALL risk was associated with lifetime moderate exposure, but not high exposure, to certain physicochemical categories of pesticides, including organophosphates, chlorinated phenols, and triazines, and with pesticides classified as insecticides or fumigants. A similar pattern was also observed for several toxicological groups of pesticides. These findings suggest future directions for the identification of specific pesticides that may play a role in the etiology of childhood leukemia.     

Comparison of pesticide levels in carpet dust and self-reported pest treatment practices in four US sites

Epidemiologic studies have used both questionnaires and carpet dust sampling to assess residential exposure to pesticides. The consistency of the information provided by these two approaches has not been explored. In a population-based case-control study of non-Hodgkin's lymphoma, carpet dust samples were collected from the homes of 513 control subjects in Detroit, Iowa, Los Angeles, and Seattle. The samples were taken from used vacuum cleaner bags and analyzed for 30 pesticides. Interviewers queried subjects about the types of pests treated in their home using a detailed questionnaire accompanied by visual aids. Geographic variations in pesticide levels were generally consistent with geographic differences in pest treatment practices. Los Angeles residents reported the most treatment for crawling insects, fleas/ticks, and termites, and Los Angeles dust samples had the highest levels of propoxur, chlorpyrifos, diazinon, permethrin, and chlordane. Iowa had the most treatment for lawn/garden weeds, and also the highest levels of 2,4-dichlorophenoxyacetic acid and dicamba. Although Seattle had the highest proportion of subjects treating for lawn/garden insects, the lawn/garden insecticides were higher in other sites. Multivariate linear regression revealed several significant associations between the type of pest treated and dust levels of specific pesticides. The strongest associations were between termite treatment and chlordane, and flea/tick treatment and permethrin. Most of the significant associations were consistent with known uses of the pesticides; few expected associations were absent. The consistency between the questionnaire data and pesticide residues measured in dust lends credibility to both methods for assessing residential exposure to pesticides. The combined techniques appear promising for epidemiologic studies. Interviewing is the only way to assess pesticide exposures before current carpets were in place. Dust sampling provides an objective measure of specific compounds to which a person may have been exposed through personal use of a pesticide or by drift-in or track-in from outside, and avoids recall bias.     

Polycyclic aromatic hydrocarbon-DNA adducts and survival among women with breast cancer

Polycyclic aromatic hydrocarbons (PAH) are mammary carcinogens in animal studies, and a few epidemiologic studies have suggested a link between elevated levels of PAH-DNA adducts and breast cancer incidence. An association between PAH-DNA adducts and survival among breast cancer cases has not been previously reported. We conducted a survival analysis among women with newly diagnosed invasive breast cancer between 1996 and 1997, enrolled in the Long Island Breast Cancer Study Project. DNA was isolated from blood samples that were obtained from cases shortly after diagnosis and assayed for PAH-DNA adducts using ELISA. Among the 722 cases with PAH-DNA adduct measurements, 97 deaths (13.4%) from all causes and 54 deaths (7.5%) due to breast cancer were reported to the National Death Index (NDI) by December 31, 2002. Using Cox proportional hazards models and controlling for age at diagnosis, we did not find evidence that all-cause mortality (hazard ratio (HR)=0.88; 95% confidence interval (CI): 0.57-1.37), or breast cancer mortality (HR=1.20; 95% CI: 0.63-2.28) was strongly associated with detectable PAH-DNA adduct levels compared with non-detectable adducts; additionally, no dose-response association was observed. Among a subgroup with treatment data (n=520), adducts were associated with over a two-fold higher mortality among those receiving radiation, but mortality for adducts was reduced among hormone therapy users. Results from this large population-based study do not provide strong support for an association between detectable PAH-DNA adducts and survival among women with breast cancer, except perhaps among those receiving radiation treatment.     

Low-serum carotenoid concentrations and carotenoid interactions predict mortality in US adults: the Third National Health and Nutrition Examination Survey

Evidence regarding the health benefits of carotenoids is controversial. Effects of serum carotenoids and their interactions on mortality have not been examined in a representative sample of US adults. The objective was to examine whether serum carotenoid concentrations predict mortality among US adults. The study consisted of adults aged ≥20 years enrolled in the Third National Health and Nutrition Examination Survey, 1988 to 1994, with measured serum carotenoids and mortality follow-up through 2006 (N = 13 293). Outcomes were all-cause, cardiovascular disease, and cancer mortality. In adjusted Cox proportional hazards models, participants in the lowest total carotenoid quartile (<1.01 μmol/L) had significantly higher all-cause mortality (mortality rate ratio, 1.38; 95% confidence interval, 1.15-1.65; P = .005) than those in the highest total carotenoid quartile (>1.75 μmol/L). For α-carotene, the highest quartile (>0.11 μmol/L) had the lowest all-cause mortality rates (P < .001). For lycopene, the middle 2 quartiles (0.29-0.58 μmol/L) had the lowest all-cause mortality rates (P = .047). Analyses with continuous carotenoids confirmed associations of serum total carotenoids, α-carotene, and lycopene with all-cause mortality (P < .001). In a random survival forest analysis, very low lycopene was the carotenoid most strongly predictive of all-cause mortality, followed by very low total carotenoids. α-Carotene/β-cryptoxanthin, α-carotene/lutein+zeaxanthin and lycopene/lutein+zeaxanthin interactions were significantly related to all-cause mortality (P < .05). Low α-carotene was the only carotenoid associated with cardiovascular disease mortality (P = .002). No carotenoids were significantly associated with cancer mortality. Very low serum total carotenoid, α-carotene, and lycopene concentrations may be risk factors for mortality, but carotenoids show interaction effects on mortality. Interventions of balanced carotenoid combinations are needed for confirmation.     

Residential pesticide usage in older adults residing in Central California

Information on residential pesticide usage and behaviors that may influence pesticide exposure was collected in three population-based studies of older adults residing in the three Central California counties of Fresno, Kern, and Tulare. We present data from participants in the Study of Use of Products and Exposure Related Behaviors (SUPERB) study (N = 153) and from community controls ascertained in two Parkinson's disease studies, the Parkinson's Environment and Gene (PEG) study (N = 359) and The Center for Gene-Environment Studies in Parkinson's Disease (CGEP; N = 297). All participants were interviewed by telephone to obtain information on recent and lifetime indoor and outdoor residential pesticide use. Interviews ascertained type of product used, frequency of use, and behaviors that may influence exposure to pesticides during and after application. Well over half of all participants reported ever using indoor and outdoor pesticides; yet frequency of pesticide use was relatively low, and appeared to increase slightly with age. Few participants engaged in behaviors to protect themselves or family members and limit exposure to pesticides during and after treatment, such as ventilating and cleaning treated areas, or using protective equipment during application. Our findings on frequency of use over lifetime and exposure related behaviors will inform future efforts to develop population pesticide exposure models and risk assessment.     

Adherence to lifestyle-related cancer prevention guidelines and breast cancer incidence and mortality

Purpose

Breast cancer is the most common cancer in women. Many lifestyle factors have been associated with an increased risk of breast cancer incidence and mortality. An index-based approach to analyzing adherence to American Cancer Society (ACS) guidelines as a whole may better explain associations between lifestyle variables and breast cancer incidence and mortality.

Regression analysis of pesticide use and breast cancer incidence in California Latinas

An evaluation of pesticide use data and breast cancer incidence rates in California Hispanic females was conducted via a regression analysis. The analysis used 1988-2000 data from the California Cancer Registry, the population-based cancer registry that monitors cancer incidence and mortality in California. It also used pesticide use data from 1970-1988 from the California Department of Pesticide Regulation. California is the leading agricultural state in the United States, and more than a quarter of all pesticides in the United States are applied there. Hispanic (Latina) females are commonly employed in agricultural operations. The authors performed regression analysis of county-level specific pesticide use data (pounds of active ingredients applied) for two classes of pesticides, organochlorines and triazine herbicides, against the breast cancer incidence rates among Latinas, controlling for age, socioeconomic status, and fertility rates, using negative binomial regression models. A total of 23,513 Latinas were diagnosed with breast cancer in California during the years 1988-1999. Risk of breast cancer was positively and significantly associated with age and socioeconomic status, and inversely and significantly associated with fertility levels. With respect to pesticides, breast cancer was positively associated with pounds of the organochlorines methoxychlor (adjusted incidence rate ratio [IRR] for highest quartile = 1.18; confidence interval [CI] = 1.03-1.35) and toxaphene (IRR = 1.16; CI = 1.01-1.34). No significant associations were found for the triazine herbicides atrazine and simazine.     

Impact of Neighborhood Racial Composition and Metropolitan Residential Segregation on Disparities in Breast Cancer Stage at Diagnosis and Survival Between Black and White Women in California

We examined the impact of metropolitan racial residential segregation on stage at diagnosis and all-cause and breast cancer-specific survival between and within black and white women diagnosed with breast cancer in California between 1996 and 2004. We merged data from the California Cancer Registry with Census indices of five dimensions of racial residential segregation, quantifying segregation among Blacks relative to Whites; block group (“neighborhood”) measures of the percentage of Blacks and a composite measure of socioeconomic status. We also examined simultaneous segregation on at least two measures (“hypersegregation”). Using logistic regression we examined effects of these measures on stage at diagnosis and Cox proportional hazards regression for survival. For all-cause and breast-cancer specific mortality, living in neighborhoods with more Blacks was associated with lower mortality among black women, but higher mortality among Whites. However, neighborhood racial composition and metropolitan segregation did not explain differences in stage or survival between Black and White women. Future research should identify mechanisms by which these measures impact breast cancer diagnosis and outcomes among Black women.     

Residential proximity to agricultural pesticide use and incidence of breast cancer in the California Teachers Study cohort

We examined the association between residential proximity to agricultural pesticide use and breast cancer incidence among members of the California Teachers Study cohort, a large study of professional school employees with extensive information on breast cancer risk factors, followed for cancer incidence since 1995. We identified 1552 invasive breast cancer cases, diagnosed between 1996 and 1999, among 114,835 cohort members. We used California Pesticide Use Reporting data to select pesticides for analysis based on use volume, carcinogenic potential, and exposure potential; a Geographic Information System was used to estimate pesticide applications within a half-mile radius of subjects' residences. We applied Cox proportional hazard models to estimate hazard rate ratios (HR) for selected pesticides, adjusting for age, race, and socioeconomic status. We saw no association between residential proximity to recent agricultural pesticide use and invasive breast cancer incidence. HR estimates for the highest compared to the lowest exposure categories for groups of agents were as follows: probable or likely carcinogens (1.07, 95% confidence interval (CI): 0.86-1.32), possible or suggestive carcinogens (1.06, 95% CI: 0.87-1.29), mammary carcinogens (1.15, 95% CI: 0.90-1.48), and endocrine disruptors (1.03, 95% CI: 0.86-1.25). HR estimates for other groups and individual pesticides did not differ from unity, nor was there a trend for any groupings of or individual pesticides examined. Stratifying by menopausal status or family history of breast cancer did not substantially affect our results. Our analyses suggest that breast cancer incidence is not elevated in areas of recent, high agricultural pesticide use in California.     

Genetic variation in base excision repair pathway genes, pesticide exposure, and prostate cancer risk

Background: Previous research indicates increased prostate cancer risk for pesticide applicators and pesticide manufacturing workers. Although underlying mechanisms are unknown, evidence suggests a role of oxidative DNA damage.Objectives: Because base excision repair (BER) is the predominant pathway involved in repairing oxidative damage, we evaluated interactions between 39 pesticides and 394 tag single-nucleotide polymorphisms (SNPs) for 31 BER genes among 776 prostate cancer cases and 1,444 male controls in a nested case–control study of white Agricultural Health Study (AHS) pesticide applicators.Methods: We used likelihood ratio tests from logistic regression models to determine p-values for interactions between three-level pesticide exposure variables (none/low/high) and SNPs (assuming a dominant model), and the false discovery rate (FDR) multiple comparison adjustment approach.Results: The interaction between fonofos and rs1983132 in NEIL3 [nei endonuclease VIII-like 3 (Escherichia coli)], which encodes a glycosylase that can initiate BER, was the most significant overall [interaction p-value (p_interact) = 9.3 × 10^–6; FDR-adjusted p-value = 0.01]. Fonofos exposure was associated with a monotonic increase in prostate cancer risk among men with CT/TT genotypes for rs1983132 [odds ratios (95% confidence intervals) for low and high use compared with no use were 1.65 (0.91, 3.01) and 3.25 (1.78, 5.92), respectively], whereas fonofos was not associated with prostate cancer risk among men with the CC genotype. Carbofuran and S-ethyl dipropylthiocarbamate (EPTC) interacted similarly with rs1983132; however, these interactions did not meet an FDR < 0.2.Conclusions: Our significant finding regarding fonofos is consistent with previous AHS findings of increased prostate cancer risk with fonofos exposure among those with a family history of prostate cancer. Although requiring replication, our findings suggest a role of BER genetic variation in pesticide-associated prostate cancer risk.