Farm Residents Research Articles

Cats on farms in the United Kingdom: numbers and preventive care

Studies concerning domestic cats on farms have historically explored social interactions and roaming patterns. Limited information exists on the numbers of farm cats, and care provided for them. Questionnaire-based exploration...

Incident thyroid disease in female spouses of private pesticide applicators

BackgroundLittle is known about modifiable risk factors for thyroid disease. Several pesticides have been implicated in thyroid disruption, but clinical implications are not clear. ObjectiveWe assessed associations between pesticide use and other farm exposures and incident hypothyroidism and hyperthyroidism in female spouses of farmers in the Agricultural Health Study (AHS). MethodsWe used Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals for risk of thyroid disease in 24,092 spouses who completed at least one follow-up questionnaire. ResultsWe identified 1627 hypothyroid and 531 hyperthyroid cases over 20 years of follow-up. The fungicides benomyl, maneb/mancozeb, and metalaxyl, the herbicide pendimethalin, and among those over 60 years of age the insecticides parathion and permethrin (applied to crops) were associated with elevated hypothyroidism risk, with HR ranging from 1.56–2.44. Conversely, the insecticide phorate, and the herbicides imazethapyr and metolachlor were associated with decreased risk (HR ranging 0.63–0.73), as were long-term farm residence and other farm-related activities (HR ranging 0.69–0.84). For hyperthyroidism, the insecticide diazinon, the fungicides maneb/mancozeb, and the herbicide metolachlor were associated with increased risk (HR ranging 1.35–2.01) and the herbicide trifluralin with decreased risk (HR: 0.57). ConclusionsSeveral individual pesticides were associated with increased risk of hypothyroidism and hyperthyroidism, although some pesticides were associated with decreased risk. Some of the findings, specifically associations with fungicides, are consistent with results from an earlier analysis of prevalent diseases in AHS spouses.

Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia: pooled and meta-analyses from the Childhood Leukemia International Consortium.

The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case–control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1–14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95% CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95% CI: 0.86, 0.99) and cats (OR = 0.87, 95% CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta‐analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves’ delayed infection hypothesis.

Healthcare utilisation prior to the diagnosis of inflammatory bowel diseases and the influence of livestock exposure: A longitudinal case-control study.

An increased prevalence of the inflammatory bowel diseases, ulcerative colitis and Crohn’s disease, was found amongst residents in a livestock dense area. We hypothesised that exposure to livestock farms might be a substantial environmental factor that contributes to the development of these diseases and that in the lead up to inflammatory bowel diseases potential risk factors can be identified. This study aimed to investigate the contribution of livestock exposure to the development of these diseases and the clinical events prior to the diagnosis. Electronic health records from 2006–2013 of general practices were used. The study population consisted of patients with a new diagnosis of inflammatory bowel diseases resident in areas with a high (n = 141) or lower (n = 109) livestock density. Patients with low back pain (n = 10,469) were used as controls. For those in a livestock dense area, distance to livestock farms was determined. Associations between morbidities and drug prescriptions in the reporting year and three years previous to the diagnosis, and the residential proximity to livestock exposure were investigated with multivariable logistic regression analyses. Acute and chronic morbidity of the gastrointestinal tract and associated drug prescriptions were predictive for the development of inflammatory bowel diseases. In addition, a positive association was found between infections and living within 500 meter of poultry farms and the development of inflammatory bowel diseases [OR: 3.3 (1.1–9.9)]. Nonetheless, overall livestock exposure contributed little to the development of these diseases. These results suggest that exposure to livestock farms on its own contributes minimal to the development of inflammatory bowel diseases. Nonetheless, having infections appeared to be a risk factor for neighbouring residents of poultry farms. More research is warranted to explain the increased prevalence of inflammatory bowel diseases amongst residents in areas with a high density of livestock.

Development of the Structure and Construction of Seaweed Farmer's Residence in Bantaeng Regency

Seaweed farmer is one of the biggest livelihoods of the society in Bantaeng Regency. The problems of seaweed farmer's residential in Bantaeng city (case study), as follows: First, the excessive utilization of the residence so that the hierarchy of the spatial is not clear. Second, utilizing the structure or construction of the residence as a place of goods storage and as a place for clothes drying that can affect the building structures security. Third, the addition of spatial on the residence without a good planning on the structure and construction of the residence. Fourth, the spatial function for seaweed processing activities built in residential areas and on the residence itself so that seaweed industry processing developed into dense, slum, without sanitation, and unfit for habitation. The purpose of the research is to analyze the structure and construction of seaweed farmer's residence reviewed from its spatial organization and function in Bantaeng Regency. The data are obtained by direct survey and field observation where the interview is conducted by using questionnaire. The society aspiration data were obtained by using Focus Group Discussion (FGD) approach. Techinal analysis is conducted by using qualitative descriptive. The result of the analysis show that: 1) The spatial in the growing and developing residence is influenced by some seaweed farmer's activity and that spatial development influences the structure and construction development of stilt house buildings that are structured or overlapping each other. The construction development is conducted independently by the owner of the residence without an appropriate or standard basic constructions. 2) The concept of the structure and development of farmer's residence maintains the construction system of Bugis-Makassar stilt house but with the procurement of spatial organization as needed by the seaweed farmer. Key words: seaweed farmers, seaweed farmers's recidence, structure and construction

Prevalence and Determinants of Sinus Problems in Farm and Non-Farm Populations of Rural Saskatchewan, Canada

Although sinus problems have long been recognized as the most common respiratory symptoms associated with agricultural work, there is a scarcity of recent studies and/or reliable estimates as to the true prevalence or risk factors of sinus problems related to farming. The aim of this study was to determine the prevalence of sinus problems in farming and non-farming rural populations and further investigate the association of individual (for example life-style, occupational), contextual (e.g., environmental), and important covariates (e.g., age, sex) with sinus problems. A large-scale cross-sectional study was conducted in farm and non-farm residents of rural Saskatchewan, Canada. A logistic regression model based on a generalized estimating equations approach were fitted to investigate the risk factors of sinus problems. Sinus problems were reported by 2755 (34.0%) of the 8101 subjects. Farm residents were more likely to spend their first year of life on farm compared with non-farm residents, and indicated a significantly lower risk of sinus problems. Meanwhile, occupational exposure to solvent and mold were associated with an increased risk of sinus problems. Some health conditions such as allergy and stomach acidity/reflux, family history, and female sex were also related to a higher risk of sinus problems. Farm residents had a significantly lower risk of sinus problems than non-farm residents, likely due to the exposure to farm specific environments in their early life.

Comparison of cancer incidence in Australian farm residents 45 years and over, compared to rural non-farm and urban residents - a data linkage study

BackgroundIt is not known if the incidence of common cancers in Australian farm residents is different to rural non-farm or urban residents.MethodsData from farm, rural non-farm and urban participants of the 45 and Up Study cohort in New South Wales, Australia, were linked with state cancer registry data for the years 2006–2009. Directly standardised rate ratios for cancer incidence were compared for all-cancer, prostate, breast, colorectal cancer, melanoma and non-Hodgkin Lymphoma (NHL). Proportional hazards regression was used to generate incidence hazard ratios for each cancer type adjusted for relevant confounders.ResultsFarm women had a significantly lower all-cancer hazard ratio than rural non-farm women (1.14, 1.01–1.29). However, the lower all-cancer risk observed in farm men, was not significant when compared to rural non-farm and urban counterparts. The all-cancer adjusted hazard ratio for combined rural non-farm and urban groups compared to farm referents, was significant for men (1.08,1.01–1.17) and women (1.13, 1.04–1.23). Confidence intervals did not exclude unity for differences in risk for prostate, breast, colorectal or lung cancers, NHL or melanoma. Whilst non-significant, farm residents had considerably lower risk of lung cancer than other residents after controlling for smoking and other factors.ConclusionsAll-cancer risk was significantly lower in farm residents compared to combined rural non-farm and urban groups. Farm women had a significantly lower all-cancer adjusted hazard ratio than rural non-farm women. These differences appeared to be mainly due to lower lung cancer incidence in farm residents.

Serotype and virulence genes of Klebsiella pneumoniae isolated from mink and its pathogenesis in mice and mink

In the study, 15 K. pneumoniae strains were isolated from the mink experiencing respiratory distress in mideastern Shandong province, China, and the prevalence of K. pneumoniae in the sampled mink was 11.9% (15/126). Fourteen (93.33%) of the 15 K. pneumoniae isolates were identified as serotype K2 and hypermucoviscosity phenotype. The 12 virulence-associated genes of the K. pneumoniae isolates were tested. The prevalence of the wabG gene for the isolates were 100% (15/15), the ureA gene 100% (15/15), the rmpA gene 93.33% (14/15), the aerobactin gene 93.33% (14/15), the uge gene 93.33% (14/15), the IucB gene 80% (12/15) and the ybtA gene 13.33% (2/15). But the other five genes, fim, iroNB, wcaG, alls and kfuBC, gave a negative PCR reaction in the 15 isolates, respectively. The animal experiments using K. pneumoniae-SD-12 and K. pneumoniae-SD-21 demonstrated that the serotype K2 was high virulence for mice and mink. These finding implied there exist potential threat that K. pneumoniae pathogens could transmit to human, especially the fur animal farm workers and residents lived near the fur animal farms. Therefore, the etiology and epidemiological surveillance of K. pneumoniae in mink should be strengthened for people’s public health.

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.

Quality of care and quality of life of people with dementia living at green care farms: a cross-sectional study

BackgroundMany countries are introducing smaller, more home-like care facilities that represent a radically new approach to nursing home care for people with dementia. The green care farm is a new type of nursing home developed in the Netherlands. The goal of this study was to compare quality of care, quality of life and related outcomes in green care farms, regular small-scale living facilities and traditional nursing homes for people with dementia.MethodsA cross-sectional design was used. Three types of nursing homes were included: (1) green care farms; (2) regular small-scale living facilities; (3) traditional nursing homes. All participating nursing homes were non-profit, collectively funded nursing homes in the south of the Netherlands. One hundred and fifteen residents with a formal diagnosis of dementia were included in the study. Data on quality of care was gathered and consisted of outcome indicators (e.g. falling incidents, pressure ulcers), structure indicators (e.g. hours per resident per day), and process indicators (e.g. presence, accessibility and content of protocols on care delivery). Furthermore, questionnaires on cognition, dependence in activities of daily living, quality of life, social engagement, neuropsychiatric symptoms, agitation, and depression were used.ResultsData showed that quality of care was comparable across settings. No large differences were found on clinical outcome measures, hours per resident per day, or process indicators. Higher quality of life scores were reported for residents of green care farms in comparison with residents of traditional nursing homes. They scored significantly higher on the Quality of Life – Alzheimer’s disease Scale (p < 0.05, ES = 0.8) indicating a better quality of life. In addition, residents of green care farms scored higher on three quality of life domains of the Qualidem: positive affect, social relations and having something to do (p < 0.05, ES > 0.7). No differences with regular small-scale living facilities were found.ConclusionsGreen care farms seem to be a valuable alternative to existing nursing homes. This is important as people with dementia are a heterogeneous group with varying needs. In order to provide tailored care there also is a need for a variety of living environments.

Farm-Boarding School Management: Linear Programming Contributions in the Search of Self-Sufficiency and Optimization

Farm schools offer a learning environment for the education of students in Agricultural Technical Programs and offer this program adopting boarding systems (“farm-boarding schools” or “FBS”). The big challenge in FBS is balancing education and production, that is, provide resources for practical classes and at the same time provide food for farm residents from a pre-defined budget by the sponsoring institution. The aim of this paper is to present a linear programming model to plan and optimize FBS production and supply. The model was applied in two FBS in Brazil. The model developed could show the complexity of the FBS system, which features a variety of productions and the interactions among them. The modeling process presented positive results from a technical and managerial point of view, including people management. The formulated model showed an optimized scenario which extended the managers’ analysis horizon and allowed safer decision making. The system’s complexity hampers dialogue between the farm-boarding school team and managers. From the modeling process and the standardization of data and generated results, there was a greater safety margin to present investment proposals and analyzes, accelerating the decision-making process, which was a positive addition to the system.

Hospital-Based Case-Control Study of MDS Subtypes and Benzene Exposure in Shanghai.

Objective:Due to the sparse data on benzene exposure and myelodysplastic syndrome (MDS) subtypes, we studied this relationship in patients from 29 hospitals in Shanghai, China.Methods:We recruited 604 cases of MDS and 1193 controls matched on age, sex, and admission date. We interviewed subjects for information on workplace and lifestyle exposures, and developed semi-quantitative exposure estimates.Results:Benzene exposure showed a direct exposure–response pattern with refractory cytopenia with multilineage dysplasia, a less certain association with refractory cytopenia with unilineage dysplasia, and no association with other MDS subtypes. A different pattern was observed with farm residence and smoking, which was primarily related to refractory anemias.Conclusions:This research demonstrates the importance of MDS subtype specification for more robust etiologic insights. Our data suggests that subtypes with non-erythroid dysplasia are associated with benzene exposure.

Serum fatty acids in infants, reflecting family fish consumption, were inverselyassociated with allergy development but not related to farm residence

目的 在这项研究中，调查农场和非农场婴儿间不同血清脂肪酸模式以及其与后续过敏的关系。同时我们也分析过敏相关血清脂肪酸和母亲饮食以及母乳脂肪酸的关系。 方法 FARMFLORA出生队列包括28例农场和37例非农场婴儿。生后4个月采集21例农场和29例对照组婴儿血清用于分析磷脂脂肪酸。由儿科医生在研究对象3岁时诊断过敏。 结果 尽管农场婴儿omega-7的18∶1的比例较低，农场和对照组婴儿的血清脂肪酸模式相似。二十碳五烯酸(eicosapentaenoic acid，EPA)的血清比例与农业状态无关，但随后发展为过敏的孩子更低，每增加0.1%EPA的优势比为0.47、95%可信区间0.27～0.83(P＝0.01)。婴儿血清EPA比例与母乳EPA比例相关，继而与产妇在哺乳期富含油脂的鱼类的摄入量相关。 结论 农场婴儿的过敏保护作用与血清脂肪酸成分无关。然而，与随后发展为过敏的儿童相比，健康婴儿血清EPA的比例的更高，可能反映出家庭饮食中富含鱼类。

Green Care Farms as Innovative Nursing Homes, Promoting Activities and Social Interaction for People With Dementia

ObjectivesInnovative care environments are developed for people with dementia to encourage person-centered care. This study aims to investigate whether residents of green care farms that provide 24-hour nursing care participate more in (physical) activities and social interaction compared with residents of other nursing homes. DesignLongitudinal observation study. SettingNursing homes in the Netherlands (green care farms, traditional nursing homes, and regular small-scale living facilities). ParticipantsA total of 115 nursing home residents at baseline, 100 at follow-up. MeasurementsEcological momentary assessments (n = 16,860) were conducted using the Maastricht Electronic Daily Life Observation Tool. Residents living at green care farms were compared with residents living in traditional nursing homes and regular small-scale living facilities. The following aspects were collected for this study: the activity performed by the participant or occurring in his or her vicinity, the engagement in the activity, the level of physical activity during the activity, the physical environment (location where the activity occurred), and the level of social interaction during the activity. ResultsIn total, 9660 baseline observations and 7200 follow-up observations were conducted. Analyses showed that residents of green care farms significantly more often participated in domestic activities (P = .004, SE = 1.6) and outdoor/nature-related activities (P = .003, SE = 0.9), and significantly less often engaged in passive/purposeless activities (P < .001, SE = 1.7) compared with residents of traditional nursing homes. Furthermore, residents of green care farms had significantly more active engagement (P = .014, SE = 0.9), more social interaction (P = .006, SE = 1.1), and came outside significantly more (P = .010, SE = 1.1) than residents of traditional nursing homes. Residents of green care farms were significantly more physically active (P = .013, SE = 0.8) than were residents of regular small-scale living facilities. No other significant differences were found. ConclusionGreen care farms can be a valuable alternative to traditional nursing homes. They provide an attractive, homelike environment and activities that positively influence engagement and social interaction. Research is needed to study how successful elements of green care farms can be implemented in existing nursing homes.

Serum fatty acids in infants, reflecting family fish consumption, wereinversely associated with allergy development but not related to farmresidence.

In this study, differences in serum fatty acid patterns between farm and nonfarm infants were investigated and related to subsequent allergy development. We also related allergy-related serum fatty acids to maternal diet and breast milk fatty acids. The FARMFLORA birth cohort included 28 farm and 37 nonfarm infants. Serum was obtained from 21 farm infants and 29 controls at four months post-partum and analysed for phospholipid fatty acids. Allergy was diagnosed by paediatricians at three years of age. Serum fatty acid patterns were similar in farm and control infants, although farm infants had lower 18:1 omega-7 proportions. Serum proportions of eicosapentaenoic acid (EPA) were unrelated to farming status, but lower in children who subsequently developed allergy, with an odds ratio of 0.47 and 95% confidence interval of 0.27-0.83 (p=0.01) for every 0.1% EPA increase. The infants' serum EPA proportions correlated with breast milk EPA proportions, which, in turn, correlated with maternal oily fish intake during lactation. The allergy-protective effect of farming was not linked to infant serum fatty acid composition. However, healthy infants had higher proportions of EPA in their sera, probably reflecting a family diet rich in fish, compared to subsequently allergic children.

Uranium contaminated drinking water linked to leukaemia—Revisiting a case study from South Africa taking alternative exposure pathways into account

The paper presents results of a follow-up to an earlier study which established a geospatial link between naturally elevated uranium (U) levels in borehole water and haematological abnormalities in local residents serving as a proxy for leukaemia prevalent in the area. While the original study focussed on drinking water only, this paper also explores alternative exposure pathways including the inhalation of dust and the food chain.U-levels in grass and tissue of sheep generally reflect U-levels in nearby borehole water and exceed background concentrations by 20 to nearly 500 times. U-levels in sheep tissue increase with age of the animal. Wool showed the highest U-concentration followed by other non-consumable tissue such as hooves, teeth and bones. Lower levels occur in edible parts such as meat and inner organs. The U-deposition rate in wool is several orders of magnitudes higher than in bone as a known target organ. Wool is an easy-to-sample non-invasive bioindicator for U-levels in meat. Depending on the original water content, dried samples show up to 5 times higher U-levels than identical fresh material.Contaminated drinking water is the main exposure pathway for farm residents resulting in U-uptake rates exceeding the WHO's tolerable daily intake (TDI) limit by up to 900%. This is somewhat mitigated by the fact that U-speciation is dominated by a neutral calcium-uranyl-carbonate complex of relatively low toxicity. Commercially available household filters are able to significantly reduce U-levels in well water and are thus recommended as a short-term intervention. Based on average consumption rates sheep meat, as local staple food, accounts for 34% of the TDI for U. Indoor levels of radon should be monitored, too, since it is linked to both, U and leukaemia. With elevated U-levels being present in other geological formations across South Africa boreholes in these areas should be surveyed.

Gender Differences in the Association of Individual and Contextual Exposures with Lung Function in a Rural Canadian Population.

To investigate the association of individual and contextual exposures with lung function by gender in rural-dwelling Canadians. A cross-sectional mail survey obtained completed questionnaires on exposures from 8263 individuals; a sub-sample of 1609 individuals (762 men, 847 women) additionally participated in clinical lung function testing. The three dependent variables were forced expired volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. Independent variables included smoking, waist circumference, body mass index, indoor household exposures (secondhand smoke, dampness, mold, musty odor), occupational exposures (grain dust, pesticides, livestock, farm residence), and socioeconomic status. The primary analysis was multiple linear regression, conducted separately for each outcome. The potential modifying influence of gender was tested in multivariable models using product terms between gender and each independent variable. High-risk waist circumference was related to reduced FVC and FEV1 for both genders, but the effect was more pronounced in men. Greater pack-years smoking was associated with lower lung function values. Exposure to household smoke was related to reduced FEV1, and exposure to livestock, with increased FEV1. Lower income adequacy was associated with reduced FVC and FEV1. High-risk waist circumference was more strongly associated with reduced lung function in men than women. Longitudinal research combined with rigorous exposure assessment is needed to clarify how sex and gender interact to impact lung function in rural populations.

Brain tumor and environmental risk factors in young people- A literature review

Introduction: Despite brain tumors being one of the most frequent tumor type in young people, little is known on their etiological factors. The main objective was to review the scientific literature on the association between exposure to environmental risk factors and brain tumors in young people. Methods: The PUBMED database was searched to identify publications on environmental risk factors (ionizing and non-ionizing radiation, heavy metals, water quality, farming, air pollution, and environmental tobacco smoke) and brain cancer in young people. Results: A total of thirty one publications were identified. Ionizing radiation was the best established environmental risk factor. We found two studies showing an increased risk, four studies showing no association and seven suggesting an increased risk between brain cancer and ionizing radiation. With respect to heavy metals, we identified one study on cadmium which found an increased risk. On water quality, two studies suggested a possible association and another one observed no increased risk, except in women who drank exclusively well water during pregnancy. Six reports showed an increased risk related to farm residence, especially when handling pesticides, while another one found an inverse association. With respect to air pollution, the four articles that we found showed an increased risk. For environmental tobacco smoke, we found one study that reported an increased risk while two other studies found no significant association. Conclusions: Ionizing radiation is the most established environmental risk factor for brain tumors. Results for other environmental risk factors are inconclusive. More studies are needed to assess the association between environmental risk factors and brain tumors in young adults.

Pesticide exposure and thyroid function in an agricultural population in Brazil

Although numerous pesticides may interfere with thyroid function, however, epidemiological evidence supporting this relationship is limited, particularly regarding modern non-persistent pesticides. We sought to evaluate the association of agricultural work practices, use of contemporary-use pesticides, and OC pesticides residue levels in serum with circulating thyroid hormone levels in an agricultural population. A cross-sectional study was conducted with a random sample of 275 male and female farm residents in Farroupilha, South of Brazil. Information on sociodemographics, lifestyle and agricultural work was obtained through questionnaire. Blood samples were collected on all participants and analyzed for cholinesterase activity, serum residues of OC pesticides, and levels of free T4 (FT4), total T3 (TT3) and TSH. Non-persistent pesticides exposure assessment was based on questionnaire information on current use of pesticides, and frequency and duration of use, among others. Associations were explored using multivariate linear regression models. Total lifetime years of use of fungicides, herbicides and dithiocarbamates in men was associated with increased TSH accompanied by decrease in FT4, with evidence of a linear trend. In addition, there was an association between being sampled in the high pesticide-use season and increased TSH levels. Conversely, farm work and lifetime use of all pesticides were related with slight decrease in TSH and increased TT3 and FT4, respectively. In general, pesticide use was not associated with thyroid hormones in women. Subjects with detected serum concentrations of β-hexachlorocyclohexane, endrin, dieldrin, heptachlor epoxide B, γ-chlordane, transnonachlor, heptachlor, p,p′-dichlorodiphenylethane and endosulfan II experienced slight changes in TT3; however, associations were weak and inconsistent. These findings suggest that both cumulative and recent occupational exposure to agricultural pesticides may affect the thyroid function causing hypothyroid-like effects, particularly in men.

Abstract 3427: Chemical exposures and risk of acute myeloid leukemia and myelodysplastic syndromes in a population-based study

Abstract Background Myelodysplastic syndromes (MDS) are a group of clonal hematologic disorders that result in ineffective hematopoiesis. Individuals with MDS have a high risk of progressing to leukemia, with approximately 30% expected to develop acute myeloid leukemia (AML). Benzene exposure is one of the few well-established risk factors for AML, and recent studies suggest it is also a risk factor for MDS. Exposure to other occupational and residential chemicals has been inconsistently associated with hematologic malignancies. In this analysis, we evaluated occupational and residential chemical exposures as risk factors for AML and MDS using population-based data. Methods AML and MDS cases were identified by rapid case ascertainment through the Minnesota Cancer Surveillance System (MCSS). Centralized pathology and cytogenetics reviews were conducted to confirm diagnosis and classify by subtypes. Controls were identified through the Minnesota State driver's license/identification card list. Chemical exposures were measured by self-report and included occupational and residential exposure to a variety of chemicals. Unconditional logistic regression with adjustment for age, sex, previous cancer treatment, income, and farm or rural residence was used to calculate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CI). Smoking, obesity and physical activity were considered as potential confounders but did not change effect estimates by 10% or more. Results We included 265 MDS cases, 420 AML cases, and 1388 controls in this analysis. As expected, we observed significant associations between benzene and both MDS and AML (OR = 1.77, 95% CI 1.17, 2.67 and OR = 2.03, 95% CI 1.45, 2.83, respectively). Exposure to vinyl chlorides was associated with MDS (OR = 2.25, 95% CI 1.32, 3.81) but not with AML (OR = 1.36, 95% CI 0.83, 2.21). Exposure to fertilizers (OR = 1.70, 95% CI 1.11, 2.59), soot (OR = 2.64, 95% CI 1.59, 4.39), creosote (OR = 1.95, 95% CI 1.08, 3.51), inks, dyes and tanning solutions (OR = 1.63, 95% 1.02, 2.60), and coal dust (2.64, 95% CI 1.30, 5.39) were associated with AML, while no association was seen between any of these exposures and MDS (range ORs = 0.78-1.25). No significant associations were observed for occupational pesticide exposures in either group. Discussion These data confirm the importance of benzene as a risk factor for myeloid malignancy and provide risk estimates in a population-based sample. A number of other significant associations with occupational and residential chemicals were observed for AML; however, all exposures were reported by only a small percentage of cases (≤10%). While chemical exposures play a clear role in the etiology of myeloid malignancy, these exposures do not account for the majority of cases. Citation Format: Jenny N. Poynter, Michaela Richardson, Michelle Roesler, Cindy K. Blair, Betsy Hirsch, Phuong Nguyen, Adina Cioc, James R. Cerhan, Erica Warlick. Chemical exposures and risk of acute myeloid leukemia and myelodysplastic syndromes in a population-based study. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3427.