Seasonal variation of acetylcholinesterase, catalase, glutathione s transferase in different size of Pinctada radiata and metal pollution (Pb, Cd, Ni) in Persian Gulf

There are various tools for monitoring the concentration of pollutants on aquatic ecosystems. Today these studies are based on biological monitoring and biomarkers. The aim of this study was to measure the concentration of the acetylcholinesterase (AChE), glutathione S-transferase and catalase as biomarkers of heavy metal contamination in pearl oyster Pinctada radiata and their mechanism in aquatic ecosystems. Heavy metals lead, cadmium and nickel were measured in soft tissue and studied stations in four seasons. Samples were collected seasonally in Lavan stations, Hendurabi and Nakhilo (in the northern Persian Gulf) from spring 2013 to winter of that year by scuba diving. Pearl oysters are divided according to their shells size; shells separated from soft tissues and were transferred to the laboratory for analysis of heavy metals and enzymes. Moopam standard method for were used for measuring the concentration of heavy metals and for analyzing tissue concentrations of glutathione S-transferase in Clam the method recommended by Habig et al in 1974 were used. For measuring acetylcholinesterase Ellman method were used. Catalase contamination in pearl oyster in the supernatant obtained from the study based on the method homogeate soft tissue of mussels (Abei, 1974) was evaluated. The results showed that the concentration of lead has significant difference in sediments station, the concentration of lead in Lavan is significantly higher than the other two stations, This could be due to the movement of tanker, boats and floating refueling and with a considerable amount of wastewater containing oil and Petroleum into the water, and also due to precipitation and industrial discharges the lead in the region is increasing, land-disposed sewage sludge, has large concentrations of lead. Compare the results of this study with standards related and other similar studies at the regional and international level showed that pollutant concentration of heavy metals in all cases significantly less than all the standards and guide values associated. And also compared to other world research results have been far less than others, Being Less of the conclusion given in this research according that nickel is one of the indicators of oil pollution in the study area and emissions have been relatively low of oil. The concentration of acetylcholinesterase at several stations, in large and small sizes and in the seasons had no significant difference. Variations of catalase, and glutathione S-transferase were almost similar to each other and parameters, station and seasons were significantly different in the concentrations of these enzymes. The effects and interaction between various parameters indicate that following parameters has impact on the concentration of catalase and glutathione S-transferase. Stations; Seasonal changes in antioxidant enzymes related to (assuming a constant in salinity and oxygen) to age, reproductive cycle, availability of food and water temperature. With increasing temperature at warm season, antioxidant enzymes were increase, with increasing temperature and abundance of food in the environment the amount of antioxidant enzymes may increase. The presence of the enzyme concentration may indicate that the higher levels of the enzyme to eliminate ROS activities to be any healthier situation. At the time of gonads maturation and spawning season catalase activity increases. This study also indicates that catalase was significantly higher in the warm season. Due to low pollutants of heavy metals in the study area, a lower level of contaminants were observed in shellfish tissue incidents of international standards and strong correlation between the amount of heavy metal contamination in pearl oyster tissue and enzymes was not observed. Therefore, we can say that the pearl oyster remains in a healthy condition and the amount of enzyme is normal.

Effects of an introduced clam (Corbicula) on water quality in the Tennessee River Valley. Presented before the second annual Sanitary Engineering Conference, Vanderbilt University, Nashville, Tenn., May 30-31, 1963.

Mode of access: Internet.

Quantification of air quality in space and time and its effects on health

The long-term adverse effects on health associated with air pollution exposure can be estimated using either cohort or spatio-temporal ecological designs. In a cohort study, the health status of a cohort of people are assessed periodically over a number of years, and then related to estimated ambient pollution concentrations in the cities in which they live. However, such cohort studies are expensive and time consuming to implement, due to the long-term follow up required for the cohort. Therefore, spatio-temporal ecological studies are also being used to estimate the long-term health effects of air pollution as they are easy to implement due to the routine availability of the required data. Spatio-temporal ecological studies estimate the health impact of air pollution by utilising geographical and temporal contrasts in air pollution and disease risk across $n$ contiguous small-areas, such as census tracts or electoral wards, for multiple time periods. The disease data are counts of the numbers of disease cases occurring in each areal unit and time period, and thus Poisson log-linear models are typically used for the analysis. The linear predictor includes pollutant concentrations and known confounders such as socio-economic deprivation. However, as the disease data typically contain residual spatial or spatio-temporal autocorrelation after the covariate effects have been accounted for, these known covariates are augmented by a set of random effects. One key problem in these studies is estimating spatially representative pollution concentrations in each areal which are typically estimated by applying Kriging to data from a sparse monitoring network, or by computing averages over modelled concentrations (grid level) from an atmospheric dispersion model. The aim of this thesis is to investigate the health effects of long-term exposure to Nitrogen Dioxide (NO2) and Particular matter (PM10) in mainland Scotland, UK. In order to have an initial impression about the air pollution health effects in mainland Scotland, chapter 3 presents a standard epidemiological study using a benchmark method. The remaining main chapters (4, 5, 6) cover the main methodological focus in this thesis which has been threefold: (i) how to better estimate pollution by developing a multivariate spatio-temporal fusion model that relates monitored and modelled pollution data over space, time and pollutant; (ii) how to simultaneously estimate the joint effects of multiple pollutants; and (iii) how to allow for the uncertainty in the estimated pollution concentrations when estimating their health effects. Specifically, chapters 4 and 5 are developed to achieve (i), while chapter 6 focuses on (ii) and (iii). In chapter 4, I propose an integrated model for estimating the long-term health effects of NO2, that fuses modelled and measured pollution data to provide improved predictions of areal level pollution concentrations and hence health effects. The air pollution fusion model proposed is a Bayesian space-time linear regression model for relating the measured concentrations to the modelled concentrations for a single pollutant, whilst allowing for additional covariate information such as site type (e.g. roadside, rural, etc) and temperature. However, it is known that some pollutants might be correlated because they may be generated by common processes or be driven by similar factors such as meteorology. The correlation between pollutants can help to predict one pollutant by borrowing strength from the others. Therefore, in chapter 5, I propose a multi-pollutant model which is a multivariate spatio-temporal fusion model that extends the single pollutant model in chapter 4, which relates monitored and modelled pollution data over space, time and pollutant to predict pollution across mainland Scotland. Considering that we are exposed to multiple pollutants simultaneously because the air we breathe contains a complex mixture of particle and gas phase pollutants, the health effects of exposure to multiple pollutants have been investigated in chapter 6. Therefore, this is a natural extension to the single pollutant health effects in chapter 4. Given NO2 and PM10 are highly correlated (multicollinearity issue) in my data, I first propose a temporally-varying linear model to regress one pollutant (e.g. NO2) against another (e.g. PM10) and then use the residuals in the disease model as well as PM10, thus investigating the health effects of exposure to both pollutants simultaneously. Another issue considered in chapter 6 is to allow for the uncertainty in the estimated pollution concentrations when estimating their health effects. There are in total four approaches being developed to adjust the exposure uncertainty. Finally, chapter 7 summarises the work contained within this thesis and discusses the implications for future research.

Histopathological and molecular effects of microplastics in Eisenia andrei Bouché

The ocean has been assumed as the main sink of microplastics (MPs), however, soils may also receive MPs from different sources and through different pathways, which may affect the biota and their role in soil functions. To the best of our knowledge, only one study, until now, reported the effects of MPs on the survival and fitness of soil organisms (Lumbricus terrestris). In our study, epigeic earthworms, of the species E. andrei, were exposed to different concentrations of MPs (0, 62.5, 125, 250, 500 and 1000 mg/kg soildw) in an OECD artificial soil and tested for reproduction, survival and growth of adults, following a standard protocol. The size of the polyethylene MPs to which earthworms were exposed ranged between 250 and 1000 μm. No significant effects were recorded on survival, number of juveniles and, in the final weight of adult earthworms after 28d of exposure, to the different concentrations of MPs. Nevertheless, FTIR-ATR of earthworms and histopathological analysis of the gut provided evidences of damages and immune system responses to MPs.

Effects od y-Fe²O³ nanoparticles on the survival and reproduction of Biomphalaria glabrata (Say, 1818) and their elimination from this benthic aquatic snail.

2016