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Environmental research [journal]
- Extracellular histones mediate the effects of metal-rich air particles on blood coagulation. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:76-82.
Epidemiological studies have shown associations of particulate matter (PM) exposure with hypercoagulability and thrombosis. Extracellular circulating histones have recently been identified as novel mediators of inflammatory and procoagulant responses. The potential roles of extracellular histones in PM-related hypercoagulability have yet not been investigated.In 63 steel workers, we evaluated the effects of exposure to PM and PM metal components on two extracellular histone modifications (H3K4me3 and H3K9ac); and the association of H3K4me3 and H3K9ac with coagulation markers.Extracellular H3K4me3 and H3K9ac were determined in plasma through enzyme-linked immunosorbent assays. Coagulation markers included endogenous thrombin potentials (ETPs), tissue-type plasminogen activator antigen (t-PA) and d-dimer. Exposure to PM with aerodynamic diameters <1μm (PM1) or <10μm (PM10) and PM10 metal components were estimated for each participant.The coagulation marker ETP, measured in the presence of soluble thrombomodulin (ETP TM+), showed significant positive associations with PM1 (β=107.84, p=0.03), PM10 (β=83.06, p=0.02), and zinc (β=75.14, p=0.03); and a marginal association with iron (β=122.58, p=0.07). Additional PM effects were observed on t-PA, D-dimer, and ETP TM+. PM1 exposure was associated with increased plasma H3K4me3 and H3K9ac (β=0.20, p=0.02; β=0.16, p=0.05, respectively). H3K4me3, but not H3K9ac, was associated with zinc (β=0.13, p=0.03) and iron (β=0.32, p=0.01) contained in PM. ETP TM+ was increased in association with higher plasma H3K4me3 (β=0.50, p=0.05) and H3K9ac (β=0.54, p=0.05).This observational study suggests potential roles of extracellular histones in PM-induced hypercoagulability. Experimental studies are warranted to further characterize these findings.
- Lead in new paints in Nepal. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:70-75.
Samples from 75 paint products made by 21 domestic and foreign manufacturers were purchased from retail stores in five major cities in Nepal and tested for lead content. Information provided on product labels were noted. Samples were selected to be representative of the large number of brands and colors available in retail shops. Although a majority of the products purchased were manufactured in Nepal, paints from four additional countries were tested. Out of a total of 75 samples, 57 (76%) of the tested paints contained lead at concentrations greater than 90ppm (ppm). Ninety-three percent of the paints that exceeded 90ppm had levels in excess of 600ppm. Lead concentrations in the tested paints ranged up to 200,000ppm (20%) lead by weight and the median concentration was 5100ppm. These results indicate that lead paint is commonly being sold for residential and other consumer applications in Nepal without any consumer warnings. Regulations are needed to specify the maximum concentration of lead allowed in paint products manufactured, imported, or distributed in the country to protect public health. Efforts must be made to get lead-containing paint products recalled from stores so that they are not used in homes, schools, and other child-occupied facilities.
- Early life perfluorooctanoic acid (PFOA) exposure and overweight and obesity risk in adulthood in a community with elevated exposure. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:62-69.
Infants and young children may be susceptible to developmental effects of perfluorooctanoic acid (PFOA) exposure. Two previous studies, one that examined a general population exposed to environmental PFOA levels and one conducted in mice exposed to experimental PFOA levels, found that early life exposure was associated with higher body mass index (BMI) in adulthood and effects may be stronger in women than in men.Examine whether elevated early life PFOA exposure was associated with adult BMI among a group of mid-Ohio valley residents exposed to a wide range of early life PFOA levels due to emissions from a chemical plant.The cohort consisted of 8764 adults aged 20-40 years who reported height and weight on a survey between 2008 and 2011. Annual retrospective early life PFOA serum concentrations were estimated for each participant based on residential history and nearby chemical plant emissions as well as background exposure not originating from the facility. We defined early life exposure as the estimated average PFOA serum concentration over the first three years of life. We examined the association between early life PFOA exposure and adult overweight (BMI ≥25kg/m(2)) and obesity (BMI ≥30kg/m(2)) risk using logistic and linear regression models.Nearly half the participants (45%) had early life PFOA exposure serum concentration estimates above background levels. Using participants who were exposed only to background PFOA levels as the referent category with quintiles of exposure above background, adjusted odds ratios (and 95% confidence intervals) for overweight risk by increasing exposure category for women were 1.0 (ref), 1.0 (0.8, 1.3), 1.0 (0.8, 1.2), 1.0 (0.8, 1.2), 0.9 (0.7, 1.1), and 0.9 (0.7, 1.1) and for men were 1.0 (ref), 0.9 (0.6, 1.1), 1.0 (0.7, 1.3), 1.0 (0.8, 1.4), 0.7 (0.5, 0.9), and 0.9 (0.7, 1.1). Odds ratios for adult obesity risk were similar. Regression coefficients from linear models using BMI as a continuous outcome showed no association between early life PFOA exposure and adult BMI.Elevated levels of PFOA exposure in early life were not associated with overweight and obesity risk in adulthood and results did not vary by sex.
- Impairment of uterine smooth muscle contractions and prostaglandin secretion from cattle myometrium and corpus luteum in vitro is influenced by DDT, DDE and HCH. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:54-61.
The aim of this study was to investigate the effect of dichlorodiphenyltrichloroethane(DDT), dichlorodiphenyldichloroethylene (DDE) and γ-hexachlorocyclohexane (HCH) (10ng/ml) on myometrial motility and the secretory function of the myometrium and corpus luteum (CL) collected from cows on days 8-12 of the estrous cycle. All of the xenobiotics increased (P<0.05) myometrial contractility. Moreover, the xenobiotics stimulated the secretion of the following prostaglandins (PGs) from myometrial strips: PGF2α, PGE2 and PGI2. DDT and DDE also increased (P<0.05) the release of PGF2α from CL strips, and HCH had the same effect (P<0.05) on the secretion of PGE2 and PGI2. The studied xenobiotics did not affect (P>0.05) PG synthesis, but DDT and DDE increased the mRNA expression levels of leukemia inhibitor factor (LIF), which can stimulate PG production. In summary, the xenobiotics affected PG secretion from cow myometrium and CL, which may contribute to the mechanism of uterine contraction disturbance.
- Indoor particulate reactive oxygen species concentrations. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:46-53.
Despite the fact that precursors to reactive oxygen species (ROS) are prevalent indoors, the concentration of ROS inside buildings is unknown. ROS on PM2.5 was measured inside and outside twelve residential buildings and eleven institutional and retail buildings. The mean (±s.d.) concentration of ROS on PM2.5 inside homes (1.37±1.2nmoles/m(3)) was not significantly different from the outdoor concentration (1.41±1.0nmoles/m(3)). Similarly, the indoor and outdoor concentrations of ROS on PM2.5 at institutional buildings (1.16±0.38nmoles/m(3) indoors and 1.68±1.3nmoles/m(3) outdoors) and retail stores (1.09±0.93nmoles/m(3) indoors and 1.12±1.1nmoles/m(3) outdoors) were not significantly different and were comparable to those in residential buildings. The indoor concentration of particulate ROS cannot be predicted based on the measurement of other common indoor pollutants, indicating that it is important to separately assess the concentration of particulate ROS in air quality studies. Daytime indoor occupational and residential exposure to particulate ROS dominates daytime outdoor exposure to particulate ROS. These findings highlight the need for further study of ROS in indoor microenvironments.
- Associations between personal exposure to air pollutants and lung function tests and cardiovascular indices among children with asthma living near an industrial complex and petroleum refineries. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:38-45.
The acute cardiorespiratory effects of air quality among children living in areas with considerable heavy industry have not been well investigated. We conducted a panel study of children with asthma living in proximity to an industrial complex housing two refineries in Montreal, Quebec, in order to assess associations between their personal daily exposure to air pollutants and changes in pulmonary function and selected indicators of cardiovascular health.Seventy-two children with asthma age 7-12 years in 2009-2010 participated in this panel study for a period of 10 consecutive days. They carried a small backpack for personal monitoring of sulphur dioxide (SO2), benzene, fine particles (PM2.5), nitrogen dioxide (NO2) and polycyclic aromatic hydrocarbons (PAHs) and underwent daily spirometry and cardiovascular testing (blood pressure, pulse rate and oxygen saturation). To estimate these associations, we used mixed regression models, adjusting for within-subject serial correlation, and for the effects of a number of personal and environmental variables (e.g., medication use, ethnicity, temperature).Children with asthma involved in the study had relatively good pulmonary function test results (mean FEV1 compared to standard values: 89.8%, mean FVC: 97.6%, mean FEF25-75: 76.3%). Median diastolic, systolic blood pressures and oxygen saturation were 60/94mmHg and 99%, respectively. Median personal concentrations of pollutants were NO2, 5.5ppb; benzene, 2.1µg/m(3); PM2.5, 5.7µg/m(3); and total PAH, 130µg/m(3). Most personal concentrations of SO2 were below the level of detection. No consistent associations were observed between cardio-pulmonary indices and personal exposure to PM2.5, NO2 and benzene, although there was a suggestion for a small decrease in respiratory function with total concentrations of PAHs (e.g., adjusted association with FVC: -9.9ml per interquartile range 95%CI: -23.4, 3.7).This study suggests that at low daily average levels of exposure to industrial emissions, effects on pulmonary and cardiovascular functions in children with asthma may be difficult to detect over 10 consecutive days.
- Leisure time activities related to carcinogen exposure and lung cancer risk in never smokers. A case-control study. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:33-37.
We aim to assess the relationship between leisure time activities related to exposure to carcinogenic substances and lung cancer risk in a hospital-based case-control study performed in never smokers. We included never smoking cases with anatomopathologically confirmed lung cancer and never smoking controls undergoing trivial surgery, at 8 Spanish hospitals. The study was conducted between January 2011 and June 2013. Participants were older than 30 and had no previous neoplasms. All were personally interviewed focusing on lifestyle, environmental tobacco smoke exposure, occupational history and leisure time activities (including duration of such activities). Results were analyzed through logistic regression and adjusted also by residential radon and education level. We included 513 never smokers, 191 cases and 322 controls. The OR for those performing the studied leisure time activities was 1.43 (95%CI 0.78-2.61). When we restricted the analysis to those performing do-it-yourself activities for more than 10 years the OR was 2.21 (95%CI 0.93-5.27). Environmental tobacco smoke exposure did not modify this association. The effect for the different lung cancer histological types was very close to significance for adenocarcinoma but only when these activities were performed for more than 10 years. We encourage health professionals to recommend protective measures for those individuals while performing these hobbies to reduce the risk of lung cancer.
- Prenatal exposure to environmental contaminants and body composition at age 7-9 years. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:24-32.
The study aim was to investigate the association between prenatal exposure to endocrine disrupting chemicals (EDCs) and the body composition of 7 to 9 year old Flemish children. The subjects were 114 Flemish children (50% boys) that took part in the first Flemish Environment and Health Study (2002-2006). Cadmium, PCBs, dioxins, p,p'-DDE and HCB were analysed in cord blood/plasma. When the child reached 7-9 years, height, weight, waist circumference and skinfolds were measured. Significant associations between prenatal exposure to EDCs and indicators of body composition were only found in girls. After adjustment for confounders and covariates, a significant negative association was found in girls between prenatal cadmium exposure and weight, BMI and waist circumference (indicator of abdominal fat) and the sum of four skinfolds (indicator of subcutaneous fat). In contrast, a significant positive association (after adjustment for confounders/covariates) was found between prenatal p,p'-DDE exposure and waist circumference as well as waist/height ratio in girls (indicators of abdominal fat). No significant associations were found for prenatal PCBs, dioxins and HCB exposure after adjustment for confounders/covariates. This study suggests a positive association between prenatal p,p'-DDE exposure and indicators of abdominal fat and a negative association between prenatal cadmium exposure and indicators of both abdominal as well as subcutaneous fat in girls between 7 and 9 years old.
- Prenatal exposure to p,p'-DDE and p,p'-DDT in relation to lower respiratory tract infections in boys from a highly exposed area of Mexico. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:19-23.
Prenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), the major breakdown product of DDT, has been associated with recurrent lower respiratory tract infections (LRTIs) in infants. However, epidemiological investigations are limited.To assess the association of prenatal exposure to p,p'-DDE and p,p'-DDT with the occurrence of LRTI in boys from Chiapas, a highly exposed area of Mexico.We analyzed data from 747 singleton boys whose prenatal exposure to p,p'-DDE and p,p'-DDT was determined in maternal serum drawn at delivery (2002-2003). LRTI (i.e., pneumonia, bronchiolitis, and other illness of the bronchi) experienced by the children were reported by their mothers during in-person interviews. The median age of the children when they were last seen was 21.4 months (quartiles 19.1 and 25.3 months).Median exposure to p,p'-DDE in this population was higher (2.7µg/g lipid) than recent U.S. levels (0.20µg/g). There were 0.19 episodes of LRTI per child-year. After adjusting for potential confounders, children in the highest category of p,p'-DDE (>9.00µg/g) exposure compared to those in the lowest (≤3.00µg/g) had an adjusted incidence rate ratio (aIRR) of LRTI of 0.77 (95% confidence interval [CI], 0.41-1.46). The corresponding aIRR for p,p'-DDT (≥2.00µg/g compared to ≤0.25µg/g) was 0.65 (95% CI: 0.30-1.39).An association of prenatal exposure to p,p'-DDE and p,p'-DDT with LRTI during childhood was not supported in this population with relatively high levels of exposure.
- Novel biomarkers of mercury-induced autoimmune dysfunction: A cross-sectional study in Amazonian Brazil. [JOURNAL ARTICLE]
- Environ Res 2014 Apr 14.:12-18.
Mercury is a ubiquitous environmental contaminant, causing both neurotoxicity and immunotoxicity. Given its ability to amalgamate gold, mercury is frequently used in small-scale artisanal gold mining. We have previously reported that elevated serum titers of antinuclear autoantibodies (ANA) are associated with mercury exposures of miners in gold mining. The goal of this project was to identify novel serum biomarkers of mercury-induced immunotoxicity and autoimmune dysregulation. We conducted an analysis of serum samples from a cross-sectional epidemiological study on miners working in Amazonian Brazil. In proteomic screening analyses, samples were stratified based on mercury concentrations and ANA titer and a subset of serum samples (N=12) were profiled using Immune Response Biomarker Profiling ProtoArray protein microarray for elevated autoantibodies. Of the up-regulated autoantibodies in the mercury-exposed cohort, potential target autoantibodies were selected based on relevance to pro-inflammatory and macrophage activation pathways. ELISAs were developed to test the entire sample cohort (N=371) for serum titers to the highest of these autoantibodies (anti-glutathione S-transferase alpha, GSTA1) identified in the high mercury/high ANA group. We found positive associations between elevated mercury exposure and up-regulated serum titers of 3760 autoantibodies as identified by ProtoArray. Autoantibodies identified as potential novel biomarkers of mercury-induced immunotoxicity include antibodies to the following proteins: GSTA1, tumor necrosis factor ligand superfamily member 13, linker for activation of T cells, signal peptide peptidase like 2B, stimulated by retinoic acid 13, and interferon induced transmembrane protein. ELISA analyses confirmed that mercury-exposed gold miners had significantly higher serum titers of anti-GSTA1 autoantibody [unadjusted odds ratio=89.6; 95% confidence interval: 27.2, 294.6] compared to emerald miners (referent population). Mercury exposure was associated with increased titers of several autoantibodies in serum including anti-GSTA1. These proteins play a wide variety of roles, including as antioxidants, in the regulation of pro- and anti-inflammatory cytokines, as well as danger and oxidative stress signaling. Dysregulation of these proteins and pathways is believed to play a role in autoimmune diseases such as rheumatoid arthritis, Sjögren׳s syndrome, and multiple sclerosis. Taken together, these results suggest that mercury exposure can induce complex autoimmune dysfunction and the immunotoxic effects of this dysfunction may be measured by serum titers to autoantibodies such as anti-GSTA1.