Effects Of Pollutant Mixtures Research Articles

Urine Metabolic Signatures of Multiple Environmental Pollutants in Pregnant Women: An Exposome Approach.

Exposure to environmental pollutants, particularly during pregnancy, can have adverse consequences on child development but little is known about the effects of pollutant mixtures on endogenous metabolism in pregnant women. We aimed to identify urinary metabolic signatures associated with low level exposure to multiple environmental pollutants in pregnant women from the INMA (INfancia y Medio Ambiente) birth cohort (Spain, N = 750). 35 chemical exposures were quantified in first trimester blood samples (organochlorine pesticides, PCBs, PFAS), in cord blood (mercury), and twice in urine at 12 and 32 weeks of pregnancy (metals, phthalates, bisphenol A). 1H nuclear magnetic resonance (NMR) metabolic profiles of urine were acquired in the same samples as pollutants. We explored associations between exposures and metabolism through an exposome-metabolome wide association scan and multivariate O2PLS modeling. Novel and reproducible associations were found across two periods of pregnancy for three nonpersistent pollutants and across two subcohorts for four of the persistent pollutants. We found novel metabolic signatures associated with arsenic exposure: TMAO and dimethylamine possibly related to gut microbial methylamine metabolism and homarine related to fish intake. Tobacco smoke exposure was related to coffee metabolism and PCBs with 3-hydroxyvaleric acid, usually released under ketoacidosis. These findings will have implications for further understanding of maternal-fetal health, and health across the life-course.

New developments in sensor technology for water quality surveillance and early warning

Sensor technologies offer particular advantages for surveillance, early warning and process control. This work aimed to provide information about practical new sensing devices that can be used for rapid field assessment of water pollution. A questionnaire completed in 2002 gathered information and data for a catalogue of sensors and instruments that can potentially be applied to soils, sediments, surface and groundwater. Demonstrations of practical sensing technologies took place at a former metal mining site near to Sevilla in 2002, and focusing on diffuse pollution in Koblenz in 2003. These exercises have confirmed that sensors and analytical methodologies can be applied on site to determine various analytes. The instruments provided information useful to manage existing water pollution problems. Some of the scientific innovations of the newest technologies consisted of improved sensitivity, the improved relevance of assays based on biomarkers, the reduced impact on the environment and the capability to detect new contaminants. Sensor technologies were also found to be useful to detect the effects of pollutant mixtures. The portability of these instruments is advantageous for on site and in situ analyses. They will help industry and regulators to deal with existing pollution and attain good water quality.

Long-term effects of sulphur dioxide on crops: an analysis of dose-response relations

Research into the effects of long-term SO 2 exposures on crop growth in the absence of visible foliar injury has progressed to a point where the data are being examined for ( a ) threshold concentrations that avoid dam age and ( b ) dose-response relations that assist cost-benefit analysis of emission control. The data from 125 exposures of 21 crops to constant concentrations of SO 2 alone in chambers have been analysed with a view to identifying threshold values and dose-response relations. The most appropriate functional form for the dose-response relation was a linear regression between SO 2 concentration and percentage yield loss. The correlation was not improved by a number of transformations of either variable, nor by normalizing for duration of exposure. Exclusion of the studies with chambers using low airflows did not significantly alter the regression equations, but did result in a substantial improvement in the correlation between SO 2 and yield loss. This analysis confirms that there is considerable variability in response between species and both between and within different exposure chambers. Reasons for the differences between chambers are discussed with reference to recent information on the effect of restricted SO 2 a flux, growth rate, plant age and other stresses on responses to long-term SO 2 exposures. Recent research has focused on the interactions between SO 2 exposure and other stresses particularly pests and diseases, frost injury, wind, frequent cutting, nutrient deficiency and possibly drought. The effects of long-term exposures to SO 2 in outdoor chambers were greatest over w inter when the metabolic capacity to de-toxify SO 2 absorbed during periods of slow growth was limited by low temperatures and low irradiance. The lower sensitivity of crops to SO 2 a under optimal conditions of indoor chambers may also be because of the reduced intensity of other stresses. Dose-response relations used in recent cost-benefit analysis of sulphur oxide emission control in Europe predict much greater economic losses than the regression equations developed in this paper. However, the relevance of dose-response relations developed from chamber studies with constant levels of SO 2 a alone will also depend upon (a) the effects of fluctuating concentrations in the field and (b) the effects of pollutant mixtures rather than SO 2 alone. It should soon be possible to develop improved dose-response relations solely from studies carried out in outdoor chambers over the complete annual cropping cycle. M any of the problems inherent in chamber studies on cereals in particular, will be avoided by the recent developments in field fumigation systems.