Residential Pesticide Exposure Research Articles

Pesticide residue exposure effect on health, growth, and development among children from agricultural area

Nowadays, the exposure to pesticides has become a matter of public health concern. The primary and secondary take-home exposure of pesticides may influence the health of communities. Farmworkers’ families generally live close to agricultural areas, which may increase the risk of residential pesticide exposure. Pesticide exposure affects children more than adults. Environmental quality drives the shifting patterns of children’s major health problems, from infectious to chronic diseases. Children’s developing organs may be exposed to low-dose concentrations of environmentally disruptive pesticides such as organophosphates, organochlorines, carbamates, and pyrethroids. Several groups of pesticide metabolites induce and inhibit growth and development in children. Potential health problems such as chronic respiratory disease, asthma, and wheezing in children were more often reported from agricultural communities than children from rural areas. Children who were in contact with pesticides during both their prenatal development and childhood reported diminished cognitive scores. This can be attributable to the elevated levels of pesticides found in their urine, which have been extensively documented. Diammonium phosphate (DAP) metabolites as one of the organophosphate pesticides (OPPs) residues correlate with high KIM-1 levels in urine, significantly leading to chronic kidney disease. DNA damage may be A potential reported effect in children from agricultural communities. Thus, to ensure children’s health and development, it is necessary to strengthen the impact of pesticide studies on children.

A Two-Pronged Educational Intervention for Caregivers to Prevent Residential Pesticide Exposure Among Thai Young Children Living in Agricultural Area.

Residential pesticide exposure can be harmful to the health of young children, particularly in agricultural areas. It is critical to educate their caregivers on pesticide exposure prevention. The purpose of this study was to determine the effectiveness of a two-pronged education intervention for caregivers in preventing pesticide exposure among Thai young children living in agricultural areas. This was an experimental study with 90 primary caregivers of young children aged 6 months to 5 years. Thirty caregivers each were assigned to one of three groups: booklet plus lecture intervention, only booklet intervention, and control. Caregivers in both interventions received a booklet that educated them on residential pesticide exposure and prevention. The caregivers in the booklet plus lecture group also attended a 2-hour lecture with the same content as the booklet. A questionnaire was developed to assess caregivers' knowledge, attitudes, intention, and behaviors regarding residential pesticide exposure and prevention in children. Face-to-face interviews were conducted at their homes three times: baseline, post-intervention, and follow-up (three weeks after the end of the intervention). Linear mixed models showed that, from baseline to post-intervention, the intervention effect on knowledge and attitude in both intervention groups, as well as intention in the booklet plus lecture group, was significant (p<0.05). From baseline to follow-up, the knowledge, attitude, intention, and behavior scores in both intervention groups increased significantly more than the control group (p<0.01). Only the attitude score increased more in the booklet plus lecture group than in the booklet group at post-intervention (p=0.009) and follow-up (p=0.003). Both the booklet plus lecture method and the booklet method alone have a positive effect on improving the caregiver's knowledge and behaviors regarding pesticide exposure prevention at home. Thus, providing a booklet to caregivers to reduce children's risk of pesticide exposure is recommended.

Exploring associations between residential exposure to pesticides and birth outcomes using the Dutch birth registry

BackgroundMaternal occupational exposure to pesticides has been linked to adverse birth outcomes but associations with residential pesticide exposures are inconclusive. ObjectivesTo explore associations between residential exposure to specific pesticides and birth outcomes using individual level exposure and pregnancy/birth data. MethodsFrom all 2009–2013 singleton births in the Dutch birth registry, we selected mothers > 16 years old living in non-urban areas, who had complete address history and changed addresses at most once during pregnancy (N = 339,947). We estimated amount (kg) of 139 active ingredients (AI) used within buffers of 50, 100, 250 and 500 m around each mother's home during pregnancy. We used generalized linear models to investigate associations between 12 AIs with evidence of reproductive toxicity and gestational age (GA), birth weight (BW), perinatal mortality, child́s sex, prematurity, low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA), adjusting for individual and area-level confounders. For the remainder 127 AIs, we used minimax concave penalty with a stability selection step to identify those that could be related to birth outcomes. ResultsRegression analyses showed that maternal residential exposure to fluroxypyr-meptyl was associated with longer GA, glufosinate-ammonium with higher risk of LBW, linuron with higher BW and higher odds of LGA, thiacloprid with lower odds of perinatal mortality and vinclozolin with longer GA. Variable selection analysis revealed that picoxystrobin was associated with higher odds of LGA. We found no evidence of associations with other AIs. Sensitivity and additional analysis supported these results except for thiacloprid. DiscussionIn this exploratory study, pregnant women residing near crops where fluroxypyr-meptyl, glufosinate-ammonium, linuron, vinclozolin and picoxystrobin were applied had higher risk for certain potentially adverse birth outcomes. Our findings provide leads for confirmatory investigations on these compounds and/or compounds with similar modes of action.

Residential exposure to pesticides and birth outcomes using the Dutch birth registry

BACKGROUND AND AIM: To explore associations between residential exposure to specific pesticides and birth outcomes using individual level exposure and pregnancy/birth data. METHODS: From all singleton births from 2009-2013 in the Dutch birth registry we selected mothers &amp;#x3e;16 years-old living in non-urban areas that had complete address history and changed addresses at most once during pregnancy (N=325,435). We selected 12 active ingredients (AIs) with some evidence of reproductive toxicity and that were used in the Netherlands according to a farmers’ survey from 2008 and explored a further 127 AIs. We estimated amount used (kg) within buffers of 50, 100, 250 and 500 meters around each mother&amp;#x27;s home during pregnancy. We used generalized linear models to investigate associations between AIs and gestational age, birth weight, low birth weight (LBW), small for gestational age (SGA), large for gestational age (LGA), still births/infant mortality, and prematurity, adjusting for individual and area-level confounders. We further used minimax concave penalty with a stability selection step to identify which AIs could further be related to the birth outcomes among the 12 and the additional 127 AIs. RESULTS: Maternal residential exposure to linuron was associated with increased birth weight [β [95% confidence interval] 296.49 [56.07, 536.90], 74.32 [27.92, 120.72], 13.87 [6.86, 20.88] and 1.93 [0.56, 3.30], in 50m, 100m, 250m and 500m buffers) and higher odds of LGA babies (OR [95% CI] 5.72 [1.04, 31.58], 1.49 [1.06, 2.08], 1.07 [1.02, 1.13], 1.01 [1.00, 1.02], respectively). Variable selection also yielded the same associations, and further identified signals for a relationship between fluroxypir-meptyl and gestational age, picoxystrobin and LGA, and glufosinate and LBW. CONCLUSIONS: Residential proximity to linuron during pregnancy was associated to increased birth weight and being large for gestational in babies. Other possible associations were identified that need further investigation. KEYWORDS: residential pesticide exposure, birth registry

Thyroid Cancer and Pesticide Use in a Central California Agricultural Area: A Case Control Study.

To examine environmental factors that influence risk of thyroid cancer. We performed a case-control study utilizing thyroid cancer cases from the California Cancer Registry (1999-2012) and controls sampled in a population-based manner. Study participants were included if they were diagnosed with thyroid cancer, lived in the study area at their time of diagnosis, and were ≥35 years of age. Controls were recruited from the same area and eligible to participate if they were ≥35 years of age and had been living in California for at least 5 years prior to the interview. We examined residential exposure to 29 agricultural use pesticides, known to cause DNA damage in vitro or are known endocrine disruptors. We employed a validated geographic information system-based system to generate exposure estimates for each participant. Our sample included 2067 cases and 1003 controls. In single pollutant models and within a 20-year exposure period, 10 out of 29 selected pesticides were associated with thyroid cancer, including several of the most applied pesticides in the United States such as paraquat dichloride [odds ratio (OR): 1.46 (95% CI: 1.23, 1.73)], glyphosate [OR: 1.33 (95% CI: 1.12, 1.58)], and oxyfluorfen [OR: 1.21 (95% CI: 1.02, 1.43)]. Risk of thyroid cancer increased proportionately to the total number of pesticides subjects were exposed to 20 years before diagnosis or interview. In all models, paraquat dichloride was associated with thyroid cancer. Our study provides first evidence in support of the hypothesis that residential pesticide exposure from agricultural applications is associated with an increased risk of thyroid cancer.

Pesticides in doormat and floor dust from homes close to treated fields: Spatio-temporal variance and determinants of occurrence and concentrations

Indoor dust has been postulated as an important matrix for residential pesticide exposure. However, there is a lack of information on presence, concentrations and determinants of multiple pesticides in dust in residential homes close to treated fields. Our objective was to characterize the spatial and temporal variance of pesticides in house dust, study the use of doormats and floors as proxies for pesticides in indoor dust and identify determinants of occurrence and concentrations. Homes within 250 m from selected bulb fields were invited to participate. Homes within 20 km from these fields but not having agricultural fields within 500 m were selected as controls. House dust was vacuumed in all homes from floors (VFD) and from newly placed clean doormats (DDM). Sampling was done during two periods, when pesticides are used and not-used. For determination of 46 prioritized pesticides, a multi-residue extraction method was used. Most statistical analyses are focused on the 12 and 14 pesticides that were detected in >40% of DDM and VFD samples, respectively. Mixed models were used to evaluate relationships between possible determinants and pesticides occurrence and concentrations in DDM and VFD. 17 pesticides were detected in more than 50% of the homes in both matrixes. Concentrations differed by about a factor five between use and non-use periods among homes within 250 m of fields and between these homes and controls. For 7 pesticides there was a moderate to strong correlation (Spearman rho 0.30–0.75) between concentrations in DDM and VFD. Distance to agricultural fields and air concentrations were among the most relevant predictors for occurrence and levels of a given pesticide in DDM. Concentrations in dust are overall higher during application periods and closer to fields (<250 m) than further away. The omnipresence of pesticides in dust lead to residents being exposed all year round.

Modifiable and Non-Modifiable Factors Affecting the Risk of Childhood Leukemia: An Overview of Meta-Analysis

Background: Numerous meta-analyses of childhood leukemia have been published, but no comprehensive study has examined the factors influencing childhood leukemia. We aimed to scrutinize the modifiable and non-modifiable factors affecting the risk of childhood leukemia. Materials and Methods: In this overview, two independent researchers screened the articles studying the effect of modifiable and non-modifiable factors on the childhood leukemia from the related databases, including Scopus, EMBASE, Cochrane, Web of Science, and Medline, without time and language restrictions from inception up to March 10, 2020. Results: Eight meta-analyses were included in this overview. Breastfeeding compared with non-breastfeeding was associated with 9% reduction in the risk of childhood leukemia (OR = 0.91). The children with the birth weight of ≥4,000 g were at a higher risk of acute lymphoblastic leukemia compared with those with low birth weight (OR = 1.26, 95% CI = 1.17, 1.37). There was a significant relationship between childhood leukemia and residential pesticide exposure (SOR=1.57). There was a relationship between influenza during pregnancy and higher risk of ALL (POR=3.64; 95% CI = 1.34-9.90), and childhood leukemia (POR=1.77). The childhood AML had a statistically significant relationship with no alcohol consumption during pregnancy. The SOR of childhood ALL had an association with paternal smoking. A statistical relationship exists between magnetic field intensity of ≥0.4 μT and childhood leukemia. The exposure to NO2 and benzene exhibited the OR of 1.64 (95% CI = 0.91-2.95) and 1.21 (95% CI = 0.97-1.52), respectively. Conclusion: Decreased breastfeeding, high birth weight, viral infections during pregnancy, alcohol consumption, maternal exposure to direct and indirect smoking, and exposure to electromagnetic fields and airborne pollutants are found to be significant risk factors for childhood leukemia.

Exposure to pesticides in adults and children living near agricultural land in the UK

S17: Residential exposure to pesticides and health effects; what we know and what we should know, Room 217, Floor 2, August 28, 2019, 1:30 PM - 3:00 PM The evidence for residential exposure to pesticides due to proximity to agricultural land is sparse. Models are used to provide input into regulatory risk assessment approaches to ensure pesticides are used safely. However, as there is limited data, it is also not clear if these models perform appropriately. We carried out a study to investigate residential pesticide exposure using biological monitoring in a number of areas in the UK with variety of arable and fruit crops and compared the results with estimates from models used for regulatory risk assessment. Farmers treating crops with captan, chlormequat, chlorpyrifos or cypermethrin provided spray event information. Adults and children residing within 100m from the sprayed fields provided first-morning void urine samples during and outwith the general spray season. Statistical analyses were carried out to determine if urinary biomarkers of these pesticides were elevated after spray events. In total, 1518 urine samples from 140 participants were available for analyses, consisting of 523 spray event and 995 background samples. For captan and cypermethrin, the proportion of values below the limit of detection was greater than 80%, with no difference between spray event and background samples. For chlormequat and chlorpyrifos, the geometric mean urinary biomarker concentrations following spray events were 15.4 μg/g creatinine and 2.5 μg/g creatinine, respectively, compared with 16.5 μg/g creatinine and 3.0 μg/g creatinine for background samples within the spraying season. Outwith the spraying season, concentrations for chlorpyrifos were the same as those within spraying season backgrounds, but for chlormequat, lower concentrations were observed outwith the spraying season (12.3 μg/g creatinine). Overall, we observed no strong evidence indicative of additional urinary pesticide biomarker excretion as a result of spray events. Consequently, the majority of measured concentrations were well below the predicted concentrations based on the models used for regulatory risk assessment.

Methods for Quantifying Residential Pesticide Exposure

Methods for Quantifying Residential Pesticide Exposure

Pesticide exposure and risk of systemic lupus erythematosus in an urban population of predominantly African-American women.

Past studies have reported associations between pesticide exposure and the risk of systemic lupus erythematosus (SLE). Residential pesticide exposure has been less well studied than agricultural exposure. The purpose of this study was to assess SLE risk associated with residential pesticide exposure in an urban population of predominantly African-American women. Adult women with SLE were identified from six hospital databases and community screening in three neighborhoods in Boston, Massachusetts, USA. Controls were adult women volunteers from the same neighborhoods who were screened for the absence of connective tissue disease and anti-nuclear antibodies. Subjects were considered exposed to pesticides if they had ever had an exterminator for an ant, cockroach, or termite problem prior to SLE diagnosis or corresponding reference age in controls. Risks associated with pesticide exposure were analyzed using multivariable logistic regression models, adjusted for sociodemographic factors. We identified 93 SLE subjects and 170 controls with similar baseline characteristics. Eighty-three per cent were African-American. Pesticide exposure was associated with SLE, after controlling for potential confounders (odds ratio 2.24, 95% confidence interval 1.28-3.93). Residential exposure to pesticides in an urban population of predominantly African-American women was associated with increased SLE risk. Additional studies are needed to corroborate these findings.

Household exposure to pesticides and risk of leukemia in children and adolescents: Updated systematic review and meta-analysis.

The role that pesticides in the domestic environment might play in the etiology of childhood leukemia remains a subject of controversy. Recent studies often reached inconsistent conclusions. To update our earlier systematic review on the association between residential/household/domestic exposure to pesticides and childhood leukemia, and to explore potential sources of heterogeneity not previously assessed. A systematic search of studies published in English between January 2009 and June 2018 was conducted in MEDLINE, and a "snowball searching" was performed from the reference list of identified publications and from Web of Science citations. Risk estimates were extracted from 15 case-control studies published between 1987 and 2018. The quality of the publications was assessed by using a modified version of the Downs and Black (1998) checklist. A random-effect meta-analysis model was used to calculate summary odds ratios (SOR) and separate analyses were conducted for acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), unspecified AL/leukemia and any leukemia types. Stratification by critical exposure period, exposure location, pesticide biocide category, child age at diagnosis, study quality, specific exposures, type of pest treated, and geographic location were performed. A statistically significant association between residential pesticide exposure and childhood leukemia was observed by combining all studies (SOR: 1.57; 95% CI: 1.27-1.95) without evidence of publication bias. Statistically significant increased risks were observed for all types of leukemia, and specifically for exposure during pregnancy, indoor exposure, prenatal exposure to insecticides and whatever the age at diagnosis. Statistical significance was also reached for high quality studies, pet treatments, professional pest control treatment and use of insect repellants, mosquito treatment and for studies from USA/Canada or International. The highest increased risks were observed for AML among children aged 2 years or less, as well as for unspecified leukemia type observed after prenatal indoor exposure. A positive association between domestic pesticide exposure and childhood leukemia is confirmed. Although the literature provides moderate to low-quality of evidence, these new results further justify the need of limiting the use of household pesticides during pregnancy and childhood.

Associations of residential exposure to agricultural pesticides with asthma prevalence in adolescence: The PIAMA birth cohort

BackgroundIt has been suggested that children who are exposed to agricultural pesticides have an increased risk of asthma, but evidence for associations betweeen residential pesticide exposure and childhood asthma is inconsistent. ObjectivesTo investigate the associations of residential pesticide exposure with the prevalence of asthma and related symptoms within a Dutch birth cohort study. MethodsIn this cross-sectional analysis, we included participants of the PIAMA birth cohort study with data on residential pesticide exposure and asthma from parent-completed questionnaires at age 14, collected in 2012 (N = 1473). We used spatial data on the presence of individual crops (cereals, open field vegetables, commercial crops, open field floriculture/bulbs, corn and potatoes) and pesticide application on these crops to estimate residential exposure to pesticides with known irritant properties for the respiratory system within distances of 100, 500, and 1000 m of the participants' homes. Logistic regression was used to estimate associations between exposure and outcomes, adjusting for potential confounders. ResultsNo associations were found between living within 100, 500 and 1000 m of agricultural fields likely treated with pesticides and symptoms of asthma. For instance, for participants living within 100 m of fields with any crops likely treated with pesticides, the adjusted odds ratios (95% confidence interval) for the prevalence of asthma, shortness of breath and dry night cough at age 14 were 0.31 (0.07, 1.32), 0.61 (0.23, 1.57) and 1.26 (0.56, 2.80), respectively. No associations were found between estimated exposure to pesticides with known irritant properties for the respiratory system and asthma or related symptoms. ConclusionsThere was no association between living near agricultural fields likely treated with pesticides and asthma and related respiratory symptoms, among our study participants.

Evaluation of the relationship between residential orchard density and dimethyl organophosphate pesticide residues in house dust.

Reducing residential pesticide exposure requires identification of exposure pathways. mCompared to the agriculture worker ‘take-home’ and residential use pathways, evidence of the ‘drift’ pathway to pesticide exposure has been inconsistent.Questionnaire data from individuals (n=99) and dust samples (n=418) from households across three growing seasons in 2011 were from the For Healthy Kids! study. Summed dimethyl organophosphate pesticide (OP) (Azinphos-Methyl, Phosmet, and Malathion) concentrations were quantified from house dust samples. Spatially-weighted orchard densities surrounding households were calculated based on various distances from homes. Regression models tested associations between orchard density, residential pesticide use, agriculture worker residents, and summed dimethyl OP house dust concentrations.Estimated relationships between orchard density and dimethyl OP in house dust were mixed: a 5% increase in orchard density resulted in 0.3% and 0.5% decreases in dimethyl OP house dust concentrations when considering land-cover 750m or 1250m away from households, respectively, but null associations with land-cover 60m or 200m away. Dimethyl OP house dust concentrations were 400% higher within homes where at least two residents were agriculture workers.Despite inconclusive evidence for the drift pathway due to potential for bias, relationships between number of agriculture workers and dimethyl OP house dust concentration underscores the take-home pathway.

Residential agricultural pesticide exposures and risks of preeclampsia

We investigated risks of preeclampsia phenotypes from potential residential pesticide exposures, including 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998–2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. The following numbers of women with preeclampsia phenotypes were identified: 1045 with superimposed (pre-existing hypertension with preeclampsia) preeclampsia (265 with gestational weeks 20–31 and 780 with gestational weeks 32–36); 3471 with severe preeclampsia (824 with gestational weeks 20–31 and 2647 with gestational weeks 32–36); and 2780 with mild preeclampsia (207 with gestational weeks 20–31 and 2573 with gestational weeks 32–36). The reference population for these groups was 197,461 women who did not have diabetes (gestational or pre-existing), did not have any hypertensive disorder, and who delivered at 37 weeks or later. The frequency of any exposure was lower or about the same in each preeclampsia case group (further delineated by gestational age), and month time period, relative to the frequency in reference population controls. Nearly all odds ratios were below 1.0 for these any vs no exposure comparisons. This study showed a general lack of increased risks between a range of agriculture pesticide exposures near women's residences and various preeclampsia phenotypes.

Residential Agricultural Pesticide Exposures and Risks of Spontaneous Preterm Birth

Pesticides exposures are aspects of the human exposome that have not been sufficiently studied for their contribution to risk for preterm birth. We investigated risks of spontaneous preterm birth from potential residential exposures to 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. After exclusions, the analytic study base included 197,461 term control births and 27,913 preterm case births. Preterm cases were more narrowly defined as 20-23 weeks (n = 515), 24-27 weeks (n = 1,792), 28-31 weeks (n = 3,098), or 32-36 weeks (n = 22,508). The frequency of any (versus none) pesticide exposure was uniformly lower in each preterm case group relative to the frequency in term controls, irrespective of gestational month of exposure. All odds ratios were below 1.0 for these any versus no exposure comparisons. The majority of odds ratios were below 1.0, many of them statistically precise, for preterm birth and exposures to specific chemical groups or chemicals. This study showed a general lack of increased risk of preterm birth associated with a range of agriculture pesticide exposures near women's residences.

Agricultural pesticide use and adverse birth outcomes in the San Joaquin Valley of California

Virtually all agricultural communities worldwide are exposed to agricultural pesticides. Yet, the health consequences of such exposure are poorly understood, and the scientific literature remains ambiguous. Using individual birth and demographic characteristics for over 500 000 birth observations between 1997–2011 in the agriculturally dominated San Joaquin Valley, California, we statistically investigate if residential agricultural pesticide exposure during gestation, by trimester, and by toxicity influences birth weight, gestational length, or birth abnormalities. Overall, our analysis indicates that agricultural pesticide exposure increases adverse birth outcomes by 5–9%, but only among the population exposed to very high quantities of pesticides (e.g., top 5th percentile, i.e., ~4200 kg applied over gestation). Thus, policies and interventions targeting the extreme right tail of the pesticide distribution near human habitation could largely eliminate the adverse birth outcomes associated with agricultural pesticide exposure documented in this study.

Childhood Residential and Agricultural Pesticide Exposures in Relation to Adult-Onset Rheumatoid Arthritis in Women.

Farming and pesticide exposure may influence risk of rheumatoid arthritis (RA); the role of early-life pesticide exposure is unknown. The Sister Study includes a US national cohort of women aged 35-74 years (enrolled 2004-2009); we examined childhood pesticide exposure in women in this cohort with adult-onset RA. Cases (n = 424) were compared with 48,919 noncases. Data included pesticide use at the longest childhood residence through age 14 years, farm residence of at least 12 months with agricultural pesticide exposure through age 18 years, and maternal farm experience. Odds ratios and 95% confidence intervals were adjusted for age, race or ethnicity, education, smoking, and childhood socioeconomic factors. Cases with RA reported more frequent and direct (personal) residential pesticide use in childhood (for infrequent/indirect pesticide use, odds ratio (OR) = 1.1; for frequent/direct use, OR = 1.8; P for trend = 0.013). Compared with women without residential farm history, odds of having RA increased for those reporting a childhood-only farm residence with personal exposure to pesticides used on crops (OR = 1.8, 95% confidence interval: 1.1, 2.9) or livestock (OR = 2.0, 95% confidence interval: 1.2, 3.3). Our findings suggest adult-onset RA may be related to childhood exposure to residential and agricultural pesticides, and support further investigations of lifetime pesticide use in RA.

Review of the published exposure data to pesticides for residents and bystanders, and for environmental risk assessment: Final report

Review of the published exposure data to pesticides for residents and bystanders, and for environmental risk assessment: Final report

Residential Pesticide Exposures in Pregnancy and the Risk of Sporadic Retinoblastoma: A Report From the Children's Oncology Group

To examine whether parental pesticide exposure contributes to the development of sporadic retinoblastoma. Case-control study. Data were collected by a large multicenter study of sporadic retinoblastoma in which parents of 99 unilateral and 56 bilateral age-matched case-control pairs were interviewed by telephone. Retrospective exposure information was collected on the type, location, timing, and frequency of residential pesticide use. We used conditional logistic regression analyses to estimate odds ratios for maternal pesticide exposure in the month before or during pregnancy and to assess whether the type of product, and the circumstances under which it was applied, were associated with risk of disease. Unilateral retinoblastoma was associated with parental insecticide use (odds ratio [OR], 2.8; confidence interval [CI], 1.1-6.7) and the use of professional lawn or landscape services (OR, 2.8; CI, 1.0-8.2). For bilateral disease we observed large point estimates for several exposures but the small number of cases rendered these results uninformative (ie, resulted in wide confidence intervals). Whether parents used the pesticide inside vs outside the home did not appear to modify risk estimates for unilateral retinoblastoma (OR, 2.5; CI, 0.9-7.0 vsOR, 2.5; CI, 1.0-6.5), nor did the type, frequency, timing related to pregnancy, or applicator of pesticideused influence estimates to an appreciable degree for disease. Our results suggest that parental pesticide exposure before or during pregnancy may play a role in the development of childhood retinoblastoma. Retrospectively collected exposure data introduces the possibility of recall bias; therefore, results should beinterpreted cautiously until additional studies are conducted.

An algorithm for quantitatively estimating non-occupational pesticide exposure intensity for spouses in the Agricultural Health Study

Purpose: Women living or working on farms may be exposed to pesticides from direct occupational use of agricultural pesticides and from non-occupational pathways, such as take-home exposure from skin, clothes and shoes of farmworkers, drift from nearby fields, and pest treatments in the home/yard. Failure to account for non-occupational pathways may underestimate total exposure, increase exposure misclassification and reduce power to detect associations in epidemiologic analyses, particularly for women who have less occupational pesticide contact than men. We developed an active-ingredient-specific algorithm for cumulative, non-occupational pesticide exposure for female spouses of pesticide applicators in the Agricultural Health Study (AHS) that quantified exposure intensity from four pathways: bystander, take-home, agricultural drift, and residential pesticide use. Methods: We used exposure data from previous meta-analyses to develop pathway weights. We used spouse and applicator responses to questions on pesticide use, farm characteristics, and other activities to identify subject-specific contrasts in pesticide exposure intensity. Results: In our algorithm, bystander exposure was a function of time a spouse spent working in fields, take-home exposure was a function of time a spouse spent at home, and both were proportional to days and years the applicator applied an active ingredient. Exposure from agricultural drift was a function of distance between homes and treated fields and days and years the applicator applied the active ingredient. Residential pesticide exposure was a function of the combined contribution of years of multiple home pest treatments, accounting for the probability the active ingredient was used in specific treatments. Conclusion: This transparent, data-driven algorithm of cumulative, aggregate pesticide exposure intensity will facilitate etiologic analyses of health effects in the AHS and could be applied to studies with similar information.