12 research outputs found

    Exposure to brominated trihalomethanes in drinking water and reproductive outcomes

    No full text
    Objectives Exposure to disinfection by-products (DBPs) during pregnancy has been associated with adverse birth outcomes. We evaluated exposure to DBPs through ingestion, inhalation and dermal absorption among pregnant women in Crete, in relation to birth weight and gestational age. Methods The mother–child birth cohort in Crete (‘Rhea’ study) enrolled 1359 pregnant women at the third month of pregnancy (2007–2008), residents in the prefecture of Heraklion. Exposures were assessed through three questionnaires administered during pregnancy requesting extensive information on personal water-related habits. Tap water samples were collected in representative mother homes on the basis of detailed water distribution patterns, and were analysed for major DBPs including trihalomethanes (THMs). Logistic and linear regression models were applied. Results Pregnant women reported a high consumption of bottled water at home (76%) and work (96%). More than half the women (59%) washed dishes by hand, nearly all women (94%) took showers rather than baths (1%), and only 2% attended a swimming pool. THM levels were low (<20 μg/l) with a high proportion of brominated compounds. When using quantitative estimates of residential exposure, we found no association with low birth weight (LBW, OR 0.7, 95% CI 0.4 to 1.4), small for gestational age for weight (SGAweight, OR 1.1, 95% CI 0.6 to 2.2) and preterm delivery (OR 0.8, 95% CI 0.5 to 1.3). Similar results were observed when taking into account uptake of THMs through all exposure routes. Conclusions We found no evidence for an increased risk of LBW, SGA and preterm delivery at the relatively low level exposure to THMs and particularly brominated THMs in Cretan drinking water

    Exposure to brominated trihalomethanes in drinking water and reproductive outcomes

    No full text
    Objectives: Exposure to disinfection by-products (DBPs) during pregnancy has been associated with adverse birth outcomes. We evaluated exposure to DBPs through ingestion, inhalation and dermal absorption among pregnant women in Crete, in relation to birth weight and gestational age. Methods: The mother-child birth cohort in Crete (&apos;Rhea&apos; study) enrolled 1359 pregnant women at the third month of pregnancy (2007-2008), residents in the prefecture of Heraklion. Exposures were assessed through three questionnaires administered during pregnancy requesting extensive information on personal water-related habits. Tap water samples were collected in representative mother homes on the basis of detailed water distribution patterns, and were analysed for major DBPs including trihalomethanes (THMs). Logistic and linear regression models were applied. Results: Pregnant women reported a high consumption of bottled water at home (76%) and work (96%). More than half the women (59%) washed dishes by hand, nearly all women (94%) took showers rather than baths (1%), and only 2% attended a swimming pool. THM levels were low (&lt;20 μg/l) with a high proportion of brominated compounds. When using quantitative estimates of residential exposure, we found no association with low birth weight (LBW, OR 0.7, 95% CI 0.4 to 1.4), small for gestational age for weight (SGAweight, OR 1.1, 95% CI 0.6 to 2.2) and preterm delivery (OR 0.8, 95% CI 0.5 to 1.3). Similar results were observed when taking into account uptake of THMs through all exposure routes. Conclusions: We found no evidence for an increased risk of LBW, SGA and preterm delivery at the relatively low level exposure to THMs and particularly brominated THMs in Cretan drinking water

    Abamectin is metabolized by CYP392A16, a cytochrome P450 associated with high levels of acaricide resistance in Tetranychus urticae

    No full text
    Abamectin is one of the most important insecticides worldwide. It is used against major agricultural pests and insects of public health importance, as well as against endoparasites in animal health. Abamectin has been used successfully for the control of the spider mite Tetranychus urticae, a major agricultural pest with global distribution, an extremely diverse host range, and a remarkable ability to develop resistance against insecticides including abamectin. Target site resistance mutations may explain a large part of resistance, although genetic evidence and transcriptomic data indicated that additional mechanisms may also be implicated in the abamectin resistant phenotype. To investigate a functional link between cytochrome P450-mediated metabolism and abamectin resistance, we recombinantly expressed three cytochrome P450s (CYP392A16, CYP392D8 and CYP392D10) that have been associated with high levels of abamectin resistance in a resistant T. urticae strain isolated from Greece. CYP392A16 was expressed predominately in its P450 form however, both CYP392D8 and CYP392D10 were expressed predominately as P420, despite optimization efforts on expression conditions. CYP392A16 catalyses the hydroxylation of abamectin (Kcat = 0.54 pmol/min/pmol P450; Km = 45.9 μM), resulting in a substantially less toxic compound as confirmed by bioassays with the partially purified metabolite. However, CYP392A16 did not metabolize hexythiazox, clofentezine and bifenthrin, active ingredients that also showed reduced toxicity in the abamectin resistant strain. Among a number of fluorescent and luminescent substrates screened, Luciferin-ME EGE was preferentially metabolized by CYP392A16, and it may be a potential diagnostic probe for metabolic resistance detection and monitoring

    Development of West-European PM<sub>2.5</sub> and NO<sub>2</sub> land use regression models incorporating satellite-derived and chemical transport modelling data.

    No full text
    Satellite-derived (SAT) and chemical transport model (CTM) estimates of PM2.5 and NO2 are increasingly used in combination with Land Use Regression (LUR) models. We aimed to compare the contribution of SAT and CTM data to the performance of LUR PM2.5 and NO2 models for Europe. Four sets of models, all including local traffic and land use variables, were compared (LUR without SAT or CTM, with SAT only, with CTM only, and with both SAT and CTM). LUR models were developed using two monitoring data sets: PM2.5 and NO2 ground level measurements from the European Study of Cohorts for Air Pollution Effects (ESCAPE) and from the European AIRBASE network. LUR PM2.5 models including SAT and SAT+CTM explained ~60% of spatial variation in measured PM2.5 concentrations, substantially more than the LUR model without SAT and CTM (adjR(2): 0.33-0.38). For NO2 CTM improved prediction modestly (adjR(2): 0.58) compared to models without SAT and CTM (adjR(2): 0.47-0.51). Both monitoring networks are capable of producing models explaining the spatial variance over a large study area. SAT and CTM estimates of PM2.5 and NO2 significantly improved the performance of high spatial resolution LUR models at the European scale for use in large epidemiological studies

    Variation of NO2 and NOx concentrations between and within 36 European study areas: Results from the ESCAPE study

    Get PDF
    The ESCAPE study (European Study of Cohorts for Air Pollution Effects) investigates long-term effects of exposure to air pollution on human health in Europe. This paper documents the spatial variation of measured NO2 and NOx concentrations between and within 36 ESCAPE study areas across Europe. In all study areas NO2 and NOx were measured using standardized methods between October 2008 and April 2011. On average, 41 sites were selected per study area, including regional and urban background as well as street sites. The measurements were conducted in three different seasons, using Ogawa badges. Average concentrations for each site were calculated after adjustment for temporal variation using data obtained from a routine monitor background site. Substantial spatial variability was found in NO2 and NOx concentrations between and within study areas; 40% of the overall NO2 variance was attributable to the variability between study areas and 60% to variability within study areas. The corresponding values for NOx were 30% and 70%. The within-area spatial variability was mostly determined by differences between street and urban background concentrations. The street/urban background concentration ratio for NO2 varied between 1.09 and 3.16 across areas. The highest median concentrations were observed in Southern Europe, the lowest in Northern Europe. In conclusion, we found significant contrasts in annual average NO2 and NOx concentrations between and especially within 36 study areas across Europe. Epidemiological long-term studies should therefore consider different approaches for better characterization of the intra-urban contrasts, either by increasing of the number of monitors or by modelling
    corecore