Occupational exposure to pesticides and Parkinson's disease: A systematic review and meta-analysis of cohort studies

ObjectivesTo systematically review available cohort studies and estimate quantitatively the association between occupational exposure to pesticides and Parkinson's disease (PD).MethodsStudies were identified from a MEDLINE search through 30 November 2011 and from the reference lists of identified publications. Relative risk (RR) estimates were extracted from 12 studies published between 1985 and 2011. Meta-rate ratio estimates (mRR) were calculated according to fixed and random-effect meta-analysis models. Meta-analyses were performed on the whole set of data and separate analyses were conducted after stratification for gender, exposure characterisation, PD cases identification, geographic location, reported risk estimator and cohort study design.ResultsA statistically significant increased risk of PD was observed when all studies were combined (mRR = 1.28; 95% confidence interval [CI]: 1.03–1.59) but there was a high heterogeneity and inconsistency among studies. The highest increased risks were observed for studies with the best design, i.e. reporting PD diagnosis confirmed by a neurologist (mRR = 2.56; CI: 1.46–4.48; n = 4), for cohort studies reporting incidence of PD (mRR = 1.95; CI: 1.29–2.97; n = 3) as well as for prospective cohorts (mRR = 1.39; CI: 1.09–1.78; n = 6). A significant increased risk was also seen for banana, sugarcane and pineapple plantation workers (mRR = 2.05; CI: 1.23–3.42; n = 2).ConclusionsThe present study provides some support for the hypothesis that occupational exposure to pesticides increases the risk of PD.     

Non-specific physical symptoms and electromagnetic field exposure in the general population: Can we get more specific? A systematic review

ObjectiveA systematic review of observational studies was performed to address the strength of evidence for an association between actual and perceived exposure to electromagnetic fields (EMF) and non-specific physical symptoms (NSPS) in the general population. To gain more insight into the magnitude of a possible association, meta-analyses were conducted.MethodsLiterature databases Medline, Embase, SciSearch, PsychInfo, Psyndex and Biosis and additional bibliographic sources such as reference sections of key publications were searched for the detection of studies published between January 2000 and April 2011.ResultsTwenty-two studies met our inclusion criteria. Qualitative assessment of the epidemiological evidence showed either no association between symptoms and higher EMF exposure or contradictory results. To strengthen our conclusions, random effects meta-analyses were performed, which produced the following results for the association with actual EMF; for symptom severity: Headache odds ratio (OR) = 1.65; 95% confidence interval (CI) = 0.88–3.08, concentration problems OR = 1.28; 95% CI = 0.56–2.94, fatigue-related problems OR = 1.15; 95% CI = 0.59–2.27, dizziness-related problems OR = 1.38; 95% CI = 0.92–2.07. For symptom frequency: headache OR = 1.01; 95% CI = 0.66–1.53, fatigue OR = 1.12; 95% CI = 0.60–2.07 and sleep problems OR = 1.18; 95% CI = 0.80–1.74. Associations between perceived exposure and NSPS were more consistently observed but a meta-analysis was not performed due to considerable heterogeneity between the studies.ConclusionsThis systematic review and meta-analysis finds no evidence for a direct association between frequency and severity of NSPS and higher levels of EMF exposure. An association with perceived exposure seems to exist, but evidence is still limited because of differences in conceptualization and assessment methods.     

Dietary exposure to cadmium and risk of breast cancer in postmenopausal women: A systematic review and meta-analysis

BackgroundWith tobacco smoking, diet is the main source of cadmium (Cd) exposure in the general population. The carcinogenic and estrogenic activities of Cd make it a contaminant of potential concern for hormone-dependent cancers including breast cancer. Postmenopausal women represent the most appropriate population to investigate the possible impact of exogenous factors with potential estrogenic activity on breast cancer as, after menopause, their estrogenic influence is predominant.ObjectivesWe systematically reviewed available studies on the association between dietary exposure to Cd and breast cancer focusing on postmenopausal women. A meta-analysis combining the risk estimators was performed and potential sources of between studies heterogeneity were traced.MethodsStudies were searched from MEDLINE through 31 January 2015 and from the reference lists of relevant publications. Six eligible studies published between 2012 and 2014 were identified and relative risk estimates were extracted. Meta-rate ratio estimates (mRR) were calculated according to fixed and random-effect models. Meta-analyses were performed on the whole set of data and separate analyses were conducted after stratification for study design, geographic location, use of hormone replacement therapy (HRT), tumor estrogen receptor status (ER + or ER −), progesterone receptor status (PGR + or PGR −), body mass index (BMI), smoker status, zinc or iron intake.ResultsNo statistically significant increased risk of breast cancer was observed when all studies were combined (mRR = 1.03; 95% confidence interval [CI]: 0.89–1.19). Several sources of heterogeneity and inconsistency were identified, including smoker status, HRT use, BMI, zinc and iron intake. Inconsistency was also strongly reduced when only considering ER −, PGR −, tumors subgroups from USA and from Japan. The risks were, however, not substantially modified after stratifications. No evidence of publication bias was found.ConclusionThe present study does not provide support for the hypothesis that dietary exposure to Cd increases the risk of breast cancer in postmenopausal women. Misclassification in dietary Cd assessment in primary studies could have biased the results towards a finding of no association.     

Exposure to multiple sources of polycyclic aromatic hydrocarbons and breast cancer incidence

BackgroundDespite studies having consistently linked exposure to single-source polycyclic aromatic hydrocarbons (PAHs) to breast cancer, it is unclear whether single sources or specific groups of PAH sources should be targeted for breast cancer risk reduction.ObjectivesThis study considers the impact on breast cancer incidence from multiple PAH exposure sources in a single model, which better reflects exposure to these complex mixtures.MethodsIn a population-based case-control study conducted on Long Island, New York (N = 1508 breast cancer cases/1556 controls), a Bayesian hierarchical regression approach was used to estimate adjusted posterior means and credible intervals (CrI) for the adjusted odds ratios (ORs) for PAH exposure sources, considered singly and as groups: active smoking; residential environmental tobacco smoke (ETS); indoor and outdoor air pollution; and grilled/smoked meat intake.ResultsMost women were exposed to PAHs from multiple sources, and the most common included active/passive smoking and grilled/smoked food intake. In multiple-PAH source models, breast cancer incidence was associated with residential ETS from a spouse (OR = 1.20, 95%CrI = 1.03, 1.40) and synthetic firelog burning (OR = 1.29, 95%CrI = 1.06, 1.57); these estimates are similar, but slightly attenuated, to those from single-source models. Additionally when we considered PAH exposure groups, the most pronounced significant associations included total indoor sources (active smoking, ETS from spouse, grilled/smoked meat intake, stove/fireplace use, OR = 1.45, 95%CrI = 1.02, 2.04).ConclusionsGroups of PAH sources, particularly indoor sources, were associated with a 30–50% increase in breast cancer incidence. PAH exposure is ubiquitous and a potentially modifiable breast cancer risk factor.     

Mercury and thyroid autoantibodies in U.S. women,NHANES 2007–2008

Associations between positive thyroid autoantibodies and total blood mercury in women were evaluated using the National Health and Nutrition Examination Survey (NHANES), 2007–2008. Women are at increased risk for autoimmune disorders, mercury exposure has been associated with cellular autoimmunity and mercury accumulates in the thyroid gland. We used multiple logistic regression to evaluate the associations between total bloodmercury and thyroglobulin autoantibody antibody positivity and thyroid peroxidase autoantibody positivity in non-pregnant, non-lactating women aged 20 and older not currently using birth control pills or other hormone therapies, adjusted for demographic factors, menopausal status, nutrient intake and urine iodine (n = 2047). Relative to women with the lowest mercury levels (≤ 0.40 μg/L), women with mercury > 1.81 μg/L (upper quintile) showed 2.24 (95% CI = 1.22, 4.12) greater odds for thyroglobulin autoantibody positivity (p_trend = 0.032); this relationship was not evident for thyroid peroxidase autoantibody positivity. Results suggest an association between mercury and thyroglobulin autoantibody positivity.     

Farm residence and reproductive health among boys in rural South Africa

BackgroundFew studies have investigated reproductive health effects of contemporary agricultural pesticides in boys.ObjectivesTo determine the association between pesticide exposure and reproductive health of boys.MethodsWe conducted a cross-sectional study in rural South Africa of boys living on and off farms. The study included a questionnaire (demographics, general and reproductive health, phyto-estrogen intake, residential history, pesticide exposures, exposures during pregnancy); and a physical examination that included sexual maturity development ratings; testicular volume; height, weight, body mass index; and sex hormone concentrations.ResultsAmong the 269 boys recruited into the study, 177 (65.8%) were categorized as farm (high pesticide exposures) and 98 (34.2%) as non-farm residents (lower pesticide exposures). Median ages of the two groups were 11.3 vs 12.0 years, respectively (p < 0.05). After controlling for confounders that included socioeconomic status, farm boys were shorter (regression coefficient (RC) = − 3.42 cm; 95% confidence interval (CI): − 6.38 to − 0.45 cm) and weighed less (RC = − 2.26 kg; CI: − 4.44 to − 0.75 kg). The farm boys also had lower serum lutenizing hormone (RC = − 0.28 IU/L; CI: − 0.48 to − 0.08 IU/L), but higher serum oestradiol (RC = 8.07 pmol/L; CI: 2.34–13.81 pmol/L) and follicle stimulating hormone (RC = 0.63 IU/L; CI: 0.19–1.08 U/L).ConclusionsOur study provides evidence that farm residence is associated with adverse growth and reproductive health of pubertal boys which may be due to environmental exposures to hormonally active contemporary agricultural pesticides.     

Male specific association between xenoestrogen levels in placenta and birthweight

BackgroundFetal exposure to endocrine disrupting chemicals may increase the risk for adverse health effects at birth or later in life.ObjectivesThe objective of this study is to analyze the combined effect of xenoestrogens on reproductive and perinatal growth outcomes (child birthweight, early rapid growth and body mass index (BMI) at 14 months) using the biomarker total effective xenoestrogen burden (TEXB).Methods490 placentas were randomly collected in the Spanish prospective birth cohort Environment and Childhood (INMA) project. TEXB was used to assess the estrogenicity of placental samples in two fractions: that largely attributable to environmental organohalogenated xenoestrogens (TEXB-alpha), and that mostly due to endogenous estrogens (TEXB-beta), both expressed in estrogen equivalent units (Eeq) per gram of tissue. Linear or logistic regression models were performed adjusting for cohort and confounders. Sex interactions were investigated.ResultsThe median TEXB-alpha level was 0.76 pM Eeq/g (interquartile range (iqr): 1.14). In multivariate models, higher TEXB-alpha levels (third tertile, > 1.22 pM Eeq/g; iqr: 1.73) were associated with increased birthweight in boys but not in girls (β = 148.2 g, 95% CI: 14.01, 282.53, p_int = 0.057). Additionally, higher TEXB-alpha values in boys were related with a lower risk of early rapid growth (OR = 0.37; 95% CI: 0.15, 0.88) and with a non significant association with larger BMI z-scores at 14 months of age (β = 0.29; 95% CI: − 0.11, 0.69).ConclusionsThese findings suggest that prenatal exposure to xenoestrogens may increase birthweight in boys, which might have an impact on child obesity and other later health outcomes.     

Association between long-term exposure to air pollution and mortality in France: A 25-year follow-up study

IntroductionLong-term exposure to air pollution (AP) has been shown to have an impact on mortality in numerous countries, but since 2005 no data exists for France.ObjectivesWe analyzed the association between long-term exposure to air pollution and mortality at the individual level in a large French cohort followed from 1989 to 2013.MethodsThe study sample consisted of 20,327 adults working at the French national electricity and gas company EDF-GDF. Annual exposure to PM₁₀, PM_10–2.5, PM_2.5, NO₂, O₃, SO₂, and benzene was assessed for the place of residence of participants using a chemistry-transport model and taking residential history into account. Hazard ratios were estimated using a Cox proportional-hazards regression model, adjusted for selected individual and contextual risk factors. Hazard ratios were computed for an interquartile range (IQR) increase in air pollutant concentrations.ResultsThe cohort recorded 1967 non-accidental deaths. Long-term exposures to baseline PM_2.5, PM_10-25, NO₂ and benzene were associated with an increase in non-accidental mortality (Hazard Ratio, HR = 1.09; 95% CI: 0.99, 1.20 per 5.9 μg/m³, PM_10-25; HR = 1.09;95% CI: 1.04, 1.15 per 2.2 μg/m³, NO₂: HR = 1.14; 95% CI: 0.99, 1.31 per 19.3 μg/m³ and benzene: HR = 1.10; 95% CI: 1.00, 1.22 per 1.7 μg/m³).The strongest association was found for PM₁₀: HR = 1.14; 95% CI: 1.05, 1.25 per 7.8 μg/m³. PM₁₀, PM_10-25 and SO₂ were associated with non-accidental mortality when using time varying exposure. No significant associations were observed between air pollution and cardiovascular and respiratory mortality.ConclusionLong-term exposure to fine particles, nitrogen dioxide, sulfur dioxide and benzene is associated with an increased risk of non-accidental mortality in France. Our results strengthen existing evidence that outdoor air pollution is a significant environmental risk factor for mortality. Due to the limited sample size and the nature of our study (occupational), further investigations are needed in France with a larger representative population sample.     

Road-traffic noise and factors influencing noise annoyance in an urban population

Noise annoyance is influenced by sound-related factors: type of noise, noise level and frequency, and person-related factors—physiological, psychological, and social factors. Prior to implementation of the Directive 2002/49/EC of the European Parliament and of the Council in Serbia, there was a need for the first comprehensive study on noise annoyance in Serbian urban population. The aim of this study was to determine principal factors for high noise annoyance in an adult urban population and to assess their predictive value. A cross-sectional study was performed on 3097 adult residents of a downtown municipality in Belgrade (1217 men and 1880 women), aged 18–96 years. Equivalent noise levels [Leq (dBA)] were measured during day, evening and night in all streets of the municipality. Noise annoyance was estimated using self-reported annoyance scale. Noise annoyance showed strong correlation with noise levels, personal characteristics and some housing conditions. Dose–response relationship was found between the percentage of highly annoyed residents and Lden. Logistic regression model identified increased risk for a high level of noise annoyance with regard to: orientation of living room/bedroom toward the street (Odds Ratio = 2.60; 95% Confidence Interval = 2.04–3.31), duration of stay at apartment during the day [OR = 1.04, 95%CI = 1.02–1.06 (per hour)], noise sensitivity [OR = 1.04, 95%CI = 1.03–1.04 (per scale unit)], and nighttime road-traffic noise level [OR = 1.03, 95%CI = 1.02–1.04 (per decibel)].     

Maternal urinary bisphenol A levels and infant low birth weight: A nested case–control study of the Health Baby Cohort in China

BackgroundExposure to bisphenol A (BPA), a known endocrine disruptor, has been demonstrated to affect fetal development in animal studies, but findings in human studies have been inconsistent.ObjectivesWe investigated whether maternal exposure to BPA during pregnancy is associated with an increased risk of infant low birth weight (LBW).MethodsA total 452 mother-infant pairs (113 LBW cases and 339 matched controls) were selected from the participants enrolled in the prospective Health Baby Cohort (HBC) in Wuhan city, China, during 2012–2014. BPA concentrations were measured in maternal urine samples collected at delivery, and the information of birth outcomes was retrieved from the medical records. A conditional logistic regression was used to evaluate the relationship between urinary BPA levels and LBW.ResultsMothers with LBW infants had significantly higher urinary BPA levels (median: 4.70 μg/L) than the control mothers (median: 2.25 μg/L) (p < 0.05). Increased risk of LBW was associated with higher maternal urinary levels of BPA [adjusted odds ratio (OR) = 3.13 for the medium tertile, 95% confidence interval (CI): 1.21, 8.08; adjusted OR = 2.49 for the highest tertile, 95% CI: 0.98, 6.36]. The association was more pronounced among female infants than among male infants, with a statistical evidence of heterogeneity in risk (p = 0.03).ConclusionsPrenatal exposure to higher levels of BPA may potentially increase the risk of delivering LBW infants, especially for female infants. This is the first case–control study to examine the association in China.     

Exposure to emissions from municipal solid waste incinerators and miscarriages: A multisite study of the MONITER Project

BackgroundMiscarriages are an important indicator of reproductive health but only few studies have analyzed their association with exposure to emissions from municipal solid waste incinerators.This study analyzed the occurrence of miscarriages in women aged 15–49 years residing near seven incinerators of the Emilia-Romagna Region (Northern Italy) in the period 2002–2006.MethodsWe considered all pregnancies occurring in women residing during the first trimester of pregnancy within a 4 km radius of each incinerator. Addresses were geocoded and exposures were characterized by a dispersion model (ADMS Urban model) producing pollution maps for incinerators based on PM₁₀ stack measurements and for other pollution sources based on NO_x ground measurements. Information on pregnancies and their outcomes was obtained from the Hospital Discharge Database. Simplified True Abortion Risks (STAR) × 100 estimated pregnancies were calculated. We ran logistic regressions adjusting for maternal characteristics, exposure to other sources of pollution, and sites, considering the whole population and stratifying by miscarriage history.ResultsThe study analyzed 11,875 pregnancies with 1375 miscarriages. After adjusting for confounders, an increase of PM₁₀ due to incinerator emissions was associated with an increased risk of miscarriage (test for trend, p = 0.042). The odds ratio for the highest quartile of exposed versus not exposed women was 1.29, 95% CI 0.97–1.72. The effect was present only for women without previous miscarriages (highest quartile of exposed versus not exposed women 1.44, 95% CI 1.06–1.96; test for trend, p = 0.009).ConclusionExposure to incinerator emissions is associated with an increased risk of miscarriage. This result should be interpreted with those of a previous study on reproductive health conducted in the same area that observed an association between incinerator exposure and preterm births.     

Recreational swimmers' exposure to Vibrio vulnificus and Vibrio parahaemolyticus in the Chesapeake Bay,Maryland, USA

Vibrio vulnificus and Vibrio parahaemolyticus are ubiquitous in the marine–estuarine environment, but the magnitude of human non-ingestion exposure to these waterborne pathogens is largely unknown. We evaluated the magnitude of dermal exposure to V. vulnificus and V. parahaemolyticus among swimmers recreating in Vibrio-populated waters by conducting swim studies at four swimming locations in the Chesapeake Bay in 2009 and 2011. Volunteers (n = 31) swam for set time periods, and surface water (n = 25) and handwash (n = 250) samples were collected. Samples were analyzed for Vibrio concentrations using quantitative PCR. Linear and logistic regressions were used to evaluate factors associated with recreational exposures. Mean surface water V. vulnificus and V. parahaemolyticus concentrations were 1128 CFU mL^− 1 (95% confidence interval (CI): 665.6, 1591.4) and 18 CFU mL^− 1 (95% CI: 9.8, 26.1), respectively, across all sampling locations. Mean Vibrio concentrations in handwash samples (V. vulnificus, 180 CFU cm^− 2 (95% CI: 136.6, 222.5); V. parahaemolyticus, 3 CFU cm^− 2 (95% CI: 2.4, 3.7)) were significantly associated with Vibrio concentrations in surface water (V. vulnificus, p < 0.01; V. parahaemolyticus, p < 0.01), but not with salinity or temperature (V. vulnificus, p = 0.52, p = 0.17; V. parahaemolyticus, p = 0.82, p = 0.06). Handwashing reduced V. vulnificus and V. parahaemolyticus on subjects' hands by approximately one log (93.9%, 89.4%, respectively). It can be concluded that when Chesapeake Bay surface waters are characterized by elevated concentrations of Vibrio, swimmers and individuals working in those waters could experience significant dermal exposures to V. vulnificus and V. parahaemolyticus, increasing their risk of infection.     

Air pollution exposure increases the risk of rheumatoid arthritis: A longitudinal and nationwide study

ObjectiveRheumatoid arthritis (RA) has been associated with inhaled pollutants in several studies, and it is a disease of chronic inflammation. The association between air pollution and the risk of RA remains unclear. Therefore, we conducted this nationwide, retrospective, sex-stratification study to evaluate this association.MethodsWe collected data from the Longitudinal Health Insurance Database (LHID), maintained by the Taiwan Bureau of National Health Insurance, and the Taiwan Air Quality-Monitoring Database (TAQMD), released by the Taiwan Environmental Protection Agency. The TAQMD provides the daily concentrations of particulate matter with the aerodynamic diameter < 2.5 μm (PM_2.5) and nitrogen dioxide (NO₂) from 74 ambient air quality-monitoring stations distributed all over Taiwan during 1998–2010. The LHID and TAQMD were linked according to the residential areas of insurants and the areas where the air quality-monitoring stations were located. A residential area was defined according to the location of the clinic and hospital that treated acute upper respiratory tract infections. The yearly average air pollutant concentrations were categorized into 4 levels based on quartiles. We evaluated the risk of RA in residents exposed to 4 levels of PM_2.5 and NO₂ concentrations.ResultsWe detected an increased risk of RA in participants exposed to PM_2.5 and NO₂. Among four quartiles of NO₂ concentration, namely Q1, Q2, Q3, and Q4, the adjusted hazard ratios (aHRs) in Q2, Q3, and Q4 compared with that in Q1 were 1.07 (95% confidence interval [CI] = 0.76–1.50), 1.63 (95% CI = 1.16–2.31),and 1.49 (95% CI = 1.05–2.12), respectively. Regarding the PM_2.5 concentrations, the aHRs after exposure to the Q2, Q3, and Q4 levels were 1.22 (95% CI = 0.85–1.74), 1.15 (95% CI = 0.82–1.62), and 0.79 (95% CI = 0.53–1.16), respectively.ConclusionThe results of this nationwide study suggest an increased risk of RA in residents exposed to NO₂.     

Perinatal exposure to dioxins and dioxin-like compounds and infant growth and body mass index at seven years: A pooled analysis of three European birth cohorts

BackgroundDioxins and dioxin-like compounds are endocrine disrupting chemicals (EDCs). Experimental studies suggest perinatal exposure to EDCs results in later obesity. However, the few epidemiological investigations on dioxins are inconclusive. We investigated perinatal exposure to dioxins and dioxin-like compounds, infant growth and body mass index (BMI) in childhood.MethodsWe pooled data from 3 European birth cohorts (Belgian, Norwegian, Slovak) with exposure assessment in cord blood or breast milk. Two cohorts had dioxin-like toxicity assessed using dioxin-responsive chemical-activated luciferase expression (DR-CALUX) bioassay and one cohort had measured concentrations of dioxins, furans and dioxin-like polychlorinated biphenols with CALUX relative potency values applied. Growth was cohort- and sex-specific change in weight-for-age z-score between birth and 24 months (N = 367). BMI was calculated at around 7 years (median 7.17, interquartile range [IQR] 7.00–7.37 years, N = 251), and overweight defined according to international standards for children equivalent to adult BMI > 25 kg/m² (Cole and Lobstein, 2012). We fitted multivariate models using generalized estimating equations, and tested effect modification by sex, breastfeeding and cohort. Results per 10 pg CALUX TEQ/g lipid increase in exposure.ResultsDioxin exposure was highest in the Belgian and lowest in the Norwegian cohort; median (IQR) of the pooled sample 13 (12.0) pg CALUX TEQ/g lipid. Perinatal exposure to dioxins and dioxin-like compounds appeared associated with increased growth between 0 and 24 months (adjusted estimate for change in z-score: β = 0.07, 95% CI: − 0.01, 0.14). At 7 years, dioxins exposure was associated with a statistically significant increase in BMI in girls (adjusted estimate for BMI units β = 0.49, 95% CI: 0.07, 0.91) but not in boys (β = − 0.03, 95% CI: − 0.55, 0.49) (p-interaction = 0.044). Furthermore, girls had a 54% (− 6%, 151%) increased risk of overweight at 7 years (p-interaction = 0.023).ConclusionPerinatal exposure to dioxin and dioxin-like compounds was associated with increased early infant growth, and increased BMI in school age girls. Studies in larger sample sizes are required to confirm these sex-specific effects.     

Reduced birth weight in relation to pesticide mixtures detected in cord blood of full-term infants

Previous research has shown that prenatal exposure to pesticides may be associated with decreased fetal growth. The specific pesticides investigated and results reported across studies have been inconsistent, and there is a mounting need for the consideration of mixtures rather than individual agents in studies of health outcomes in relation to environmental exposures. There are also many individual pesticides that have not been investigated in human health studies to date. We conducted a pilot study in rural Zhejiang province, China, measuring 20 non-persistent pesticides (10 insecticides, 6 herbicides, 3 fungicides, and 1 repellant) in umbilical cord blood of 112 full term (> 37 weeks) infants. The pesticides detected with the greatest frequency were diethyltoluamide (DEET) (73%), a repellant, and vinclozolin (49%), a fungicide. The samples had detectable concentrations for a mean of 4.6 pesticides (SD = 1.9) with a maximum of 10. Adjusting for potential confounders, newborn birth weight was inversely associated with the number of pesticides detected in cord blood (p = 0.04); birth weight decreased by a mean of 37.1 g (95% CI, − 72.5 to − 1.8) for each detected pesticide. When assessing relationships by pesticide type, detection of fungicides was also associated with decreased birth weight (adjusted β = − 116 g [95% CI, − 212 to − 19.2]). For individual pesticides analyzed as dichotomous (detect vs. non-detect) variables, only vinclozolin (adjusted β = − 174 g [95% CI, − 312 to − 36.3]) and acetochlor (adjusted β = − 165 g [95% CI, − 325 to − 5.7]) were significantly associated with reduced birth weight. No significant associations were seen between birth weight and individual pesticides assessed as continuous or 3-level ordinal variables. Our findings from this pilot investigation suggest that exposure to fungicides may adversely impact fetal growth. Exposure to mixtures of multiple pesticides is also of concern and should be explored in addition to individual pesticides. Additional research is needed to establish causality and to understand the function and impact of fungicides and pesticide mixtures on fetal development.     

Chronic disease prevalence in women and air pollution — A 30-year longitudinal cohort study

BackgroundAir pollution, such as fine particulate matter (PM_2.5), can increase risk of adverse health events among people with heart disease, diabetes, asthma and chronic obstructive pulmonary disease (COPD) by aggravating these conditions. Identifying the influence of PM_2.5 on prevalence of these conditions may help target interventions to reduce disease morbidity among high-risk populations.ObjectivesThe objective of this study is to measure the association of exposure of PM_2.5 with prevalence risk of various chronic diseases among a longitudinal cohort of women.MethodsWomen from Ontario who enrolled in the Canadian National Breast Screening Study (CNBSS) from 1980 to 1985 (n = 29,549) were linked to provincial health administrative data from April 1, 1992 to March 31, 2013 to determine the prevalence of major chronic disease and conditions (heart disease, diabetes, asthma, COPD, acute myocardial infarction, angina, stroke and cancers). Exposure to PM_2.5 was measured using satellite data collected from January 1, 1998 to December 31, 2006 and assigned to resident postal-code at time of entry into study. Poisson regression models were used to describe the relationship between exposure to ambient PM_2.5 and chronic disease prevalence. Prevalence rate ratios (PRs) were estimated while adjusting for potential confounders: baseline age, smoking, BMI, marital status, education and occupation. Separate models were run for each chronic disease and condition.ResultsCongestive heart failure (PR = 1.31, 95% CI: 1.13, 1.51), diabetes (PR = 1.28, 95% CI: 1.16, 1.41), ischemic heart disease (PR = 1.22, 95% CI: 1.14, 1.30), and stroke (PR = 1.21, 95% CI: 1.09, 1.35) showed over a 20% increase in PRs per 10 μg/m³ increase in PM_2.5 after adjusting for risk factors. Risks were elevated in smokers and those with BMI greater than 30.ConclusionsThis study estimated significant elevated prevalent rate ratios per unit increase in PM_2.5 in nine of the ten chronic diseases studied.     

Protective glove use and hygiene habits modify the associations of specific pesticides with Parkinson's disease

Pesticides have been associated with Parkinson's disease (PD), and protective gloves and workplace hygiene can reduce pesticide exposure. We assessed whether use of gloves and workplace hygiene modified associations between pesticides and PD. The Farming and Movement Evaluation (FAME) study is a nested case–control study within the Agricultural Health Study. Use of protective gloves, other PPE, and hygiene practices were determined by questionnaire (69 cases and 237 controls were included). We considered interactions of gloves and hygiene with ever-use of pesticides for all pesticides with ≥ 5 exposed and unexposed cases and controls in each glove-use stratum (paraquat, permethrin, rotenone, and trifluralin). 61% of respondents consistently used protective gloves and 87% consistently used ≥ 2 hygiene practices. Protective glove use modified the associations of paraquat and permethrin with PD: neither pesticide was associated with PD among protective glove users, while both pesticides were associated with PD among non-users (paraquat OR 3.9 [95% CI 1.3, 11.7], interaction p = 0.15; permethrin OR 4.3 [95% CI 1.2, 15.6] interaction p = 0.05). Rotenone was associated with PD regardless of glove use. Trifluralin was associated with PD among participants who used < 2 hygiene practices (OR 5.5 [95% CI 1.1, 27.1]) but was not associated with PD among participants who used 2 or more practices (interaction p = 0.02). Although sample size was limited in the FAME study, protective glove use and hygiene practices appeared to be important modifiers of the association between pesticides and PD and may reduce risk of PD associated with certain pesticides.     

Air pollution and hospitalization for acute complications of diabetes in Chile

Exposure to air pollution has been shown to cause insulin resistance in mice. To determine the relevance to humans, we tested the association between daily air pollution concentrations and daily hospitalization for acute serious complications of diabetes, coma and ketoacidosis, in Santiago between 2001 and 2008, using generalized linear models with natural splines to control for long term trends.For an interquartile range (IQR) increase in air pollutant, the relative risks (95% CI) of hospitalization for diabetes were: 1.15 (1.10, 1.20) for carbon monoxide (IQR = 1.00); 1.07 (0.98, 1.16) for ozone (IQR = 63.50); 1.14 (1.06, 1.22) for sulfur dioxide (IQR = 5.88); 1.12(1.05, 1.20) for nitrogen dioxide (IQR = 27.94); 1.11 (1.07, 1.15) for particulate matter ≤ 10 μm diameter(IQR = 34.00); and 1.11 (1.06, 1.16) for fine particulate matter ≤ 2.5 μm diameter (IQR = 18.50). Results were similar when stratified by age, sex and season. Air pollution appears to increase the risk of acute complications of diabetes requiring hospitalization, suggesting that improvements in air quality may reduce morbidity from diabetes.     

Application of the Navigation Guide systematic review methodology to the evidence for developmental and reproductive toxicity of triclosan

BackgroundThere are reports of developmental and reproductive health effects associated with the widely used biocide triclosan.ObjectiveApply the Navigation Guide systematic review methodology to answer the question: Does exposure to triclosan have adverse effects on human development or reproduction?MethodsWe applied the first 3 steps of the Navigation Guide methodology: 1) Specify a study question, 2) Select the evidence, and 3) Rate quality and strength of the evidence. We developed a protocol, conducted a comprehensive search of the literature, and identified relevant studies using pre-specified criteria. We assessed the number and type of all relevant studies. We evaluated each included study for risk of bias and rated the quality and strength of the evidence for the selected outcomes. We conducted a meta-analysis on a subset of suitable data.ResultsWe found 4282 potentially relevant records, and 81 records met our inclusion criteria. Of the more than 100 endpoints identified by our search, we focused our evaluation on hormone concentration outcomes, which had the largest human and non-human mammalian data set. Three human studies and 8 studies conducted in rats reported thyroxine levels as outcomes. The rat data were amenable to meta-analysis. Because only one of the human thyroxine studies quantified exposure, we did not conduct a meta-analysis of the human data. Through meta-analysis of the data for rats, we estimated for prenatal exposure a 0.09% (95% CI: − 0.20, 0.02) reduction in thyroxine concentration per mg triclosan/kg-bw in fetal and young rats compared to control. For postnatal exposure we estimated a 0.31% (95% CI: − 0.38, − 0.23) reduction in thyroxine per mg triclosan/kg-bw, also compared to control. Overall, we found low to moderate risk of bias across the human studies and moderate to high risk of bias across the non-human studies, and assigned a “moderate/low” quality rating to the body of evidence for human thyroid hormone alterations and a “moderate” quality rating to the body of evidence for non-human thyroid hormone alterations.ConclusionBased on this application of the Navigation Guide systematic review methodology, we concluded that there was “sufficient” non-human evidence and “inadequate” human evidence of an association between triclosan exposure and thyroxine concentrations, and consequently, triclosan is “possibly toxic” to reproductive and developmental health. Thyroid hormone disruption is an upstream indicator of developmental toxicity. Additional endpoints may be identified as being of equal or greater concern as other data are developed or evaluated.     

Association between maternal exposure to perfluorooctanoic acid (PFOA) from electronic waste recycling and neonatal health outcomes

ObjectivePerfluorooctanoic acid (PFOA) has applications in numerous industrial and consumer products. The widespread prevalence of PFOA in humans demonstrated in recent studies has drawn considerable interest from the public. We aimed to evaluate the exposure of mothers to PFOA and the potential hazards to neonates in a primitive electronic waste recycling area, Guiyu, China, and a control area, Chaonan, China.MethodsOur investigation included analyses of maternal serum samples, health effect examinations, and other relevant factors. Questionnaires were administered and maternal serum samples were collected for 167 pregnant women. Solid phase extraction method was used for all analytical sample preparation, and analyses were completed using high performance liquid chromatography tandem mass spectrometry method.ResultsThe PFOA concentration was higher in maternal serum samples from Guiyu than in samples from Chaonan (median 16.95, range 5.5–58.5 ng mL^− 1; vs. 8.7, range 4.4–30.0 ng mL^− 1; P < 0.001). Residence in Guiyu, involvement in e-waste recycling, husband's involvement in e-waste and use of the family residence as workshop were significant factors contributing to PFOA exposure. Maternal PFOA concentrations were significantly different between normal births and adverse birth outcomes including premature delivery, term low birth weight, and stillbirths. After adjusting for potential confounders, PFOA was negatively associated with gestational age [per lg-unit: β = − 15.99 days, 95% confidence interval (CI), − 27.72 to − 4.25], birth weight (per lg-unit: β = − 267.3 g, 95% CI, − 573.27 to − 37.18), birth length (per lg-unit: β = − 1.91 cm, 95% CI, − 3.31 to − 0.52), and Apgar scores (per lg-unit: β = − 1.37, 95% CI, − 2.42 to − 0.32), but not associated with ponderal index.ConclusionsMothers from Guiyu were exposed to higher levels of PFOA than those from control areas. Prenatal exposure to PFOA was associated with decreased neonatal physical development and adverse birth outcomes.