The effects of plastic related phthalates (DEHP) upon ragworm, Hediste diversicolor

The exposure of the general public to phthalates is widespread as well as quite variable. Many human consumer products consist of a range of phthalates as ingredients of plastic materials. These include building materials, clothing, household furniture, cosmetics, pharmaceuticals, medical equipment, dentures, nutritional supplements, food packaging materials, children toys, modeling clay, waxes, glow sticks, cleaning materials, lubricants, automobile parts and also some insecticides (Schettler, 2005).Animals are exposed in their natural habitats to a variety of human activities including those related to dissolved chemicals that are released into aquatic systems and may impact their fitness and survival. The responses of animals to stress, generated by these chemicals, determines their biochemical and behavioural fitness. Phthalate esters are example of such chemicals. Di-2-ethylhexyl phthalate (DEHP) and Hediste diversicolor were used for the purpose of this study. Hediste diversicolor were exposed to various low concentrations of 0.05, 2, and 10 μg/L of DEHP in long term exposures (3 months), and to high concentrations of 100, and 500 μg/L DEHP in short term exposure studies (7 days). The study aims to provide evidence that the accumulation of DEHP in H. diversicolor results in changes to their behaviours, specifically feeding and burrowing activity, as well as changes in their biochemical responses to phthalate driven oxidative stress via catalase and superoxide dismutase enzymes. DEHP showed different levels of persistence in seawater depending on concentrations. DEHP accumulated significantly more in H. diversicolor and persisted also in the sediment, while it degraded quickly in seawater. Exposure to DEHP generated behavioural impairments in H. diversicolor in the form of a decrease in the feeding time and an increase in the burrowing time, a typical predator escape behaviour. In addition to this stressed worm also showed an increase in two biomarkers of oxidative-stress, CAT enzymes and stability in SOD enzymes. Field samples showed fluctuations of DEHP over the year and significant differences in DEHP levels between various locations in the Humber Estuary, but generally DEHP levels are significantly higher in H. diversicolor followed by the sediment and seawater

Chitosan nano-composites applications for water remediation

AbstractWater is the most crucial element for living, and the lack of pure and clean water has increased globally. Hence, the need for water remediation from different pollutants is a must. Developing different techniques to accomplish water purification is expanding every day. Chitosan is a biodegradable and eco-friendly biopolymer which is extensively used in various applications. Here, we focus on using chitosan nano complexes with ferrites, graphene, silver, and silica nanoparticles as novel, cheap, accurate, biocompatible, reusable, and fast nano-complexes. Different synthesis protocols were used to obtain Chitosan-nano complexes. Various techniques were used to characterize and test the synthesized nanocomplexes, such as UV-Vis spectroscopy, Fourier transforms infrared spectroscopy (FT-IR), powder-X-ray diffraction (p-XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Brunauer—Emmett–Teller (BET) analysis and Inductively coupled plasma mass spectrometry (ICP-MS). The chitosan-based nanocomplexes are used for water purification and detecting different chemical pollutants such as heavy metals, organic and dyes contaminations, and eliminating different pathogenic microorganisms from the environment

Environmental Risk Assessment of Petroleum Activities in Surface Sediments, Suez Gulf, Egypt

The present study focuses on the risk assessment of heavy metal contamination in aquatic ecosystems by evaluating the current situation of heavy metals in seven locations (North Amer El Bahry, Amer, Bakr, Ras Gharib, July Water Floud, Ras Shokeir, and El Marageen) along the Suez Gulf coast that are well-known representative sites for petroleum activities in Egypt. One hundred and forty-six samples of surface sediments were carefully collected from twenty-seven profiles in the intertidal and surf zone. The hydrochemical parameters, such as pH and salinity (S‰), were measured during sample collection. The mineralogy study was carried out by an X-ray diffractometer (XRD), and the concentrations of Al, Mn, Fe, Cr, Cu, Co, Zn, Cd, and Pb were determined using inductively coupled plasma mass spectra (ICP-MS). The ecological risks of heavy metals were assessed by applying the contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI). The mineralogical composition mainly comprised quartz, dolomites, calcite, and feldspars. The average concentrations of the detected heavy metals, in descending order, were Al > Fe > Mn > Cr > Pb > Cu > Zn > Ni > Co > Cd. A non-significant or negative relationship between the heavy metal concentration in the samples and their textural grain size characteristics was observed. The coastal surface sediment samples of the Suez Gulf contained lower concentrations of heavy metals than those published for other regions in the world with petroleum activities, except for Al, Mn, and Cr. The results for the CF, EF, and Igeo showed that Cd and Pb have severe enrichment in surface sediment and are derived from anthropogenic sources, while Al, Mn, Fe, Cr, Co, Ni, Cu, and Zn originate from natural sources. By comparison, the PLI and RI results indicate that the North Amer El Bahry and July Water Floud are considered polluted areas due to their petroleum activities. The continuous monitoring and assessment of pollutants in the Suez Gulf will aid in the protection of the environment and the sustainability of resources

Integration of Water Quality Indices and Multivariate Modeling for Assessing Surface Water Quality in Qaroun Lake, Egypt

Water quality has deteriorated in recent years as a result of rising population and unplanned development, impacting ecosystem health. The water quality parameters of Qaroun Lake are contaminated to varying degrees, particularly for aquatic life consumption. For that, the objective of this work is to improve the assessments of surface water quality and to determine the different geo-environmental parameters affecting the lake environmental system in Qaroun Lake utilizing the weighted arithmetic water quality index (WAWQI) and four pollution indices (heavy metal pollution index (HPI), metal index (MI), contamination index (Cd), and pollution index (PI), that are enhanced by multivariate analyses as cluster analysis (CA), principal component analysis (PCA), and support vector machine regression (SVMR). Surface water samples were collected at 16 different locations from the lake during years 2018 and 2019. Thirteen physiochemical parameters were measured and used to calculate water quality indices (WQIs). The WQIs of Qaroun Lake such WAWQI, HPI, MI, Cd, PI revealed a different degree of contamination, with respect to aquatic life utilization. The WQIs result revealed that surface water in the lake is unsuitable, high polluted, and seriously affected by pollution for an aquatic environment. The PI findings revealed that surface water samples of Qaroun Lake were significantly impacted by Al, moderately affected by Cd and Cu, and while slightly affected by Zn due to uncontrolled releases of domestic and industrial wastewater. Furthermore, increasing salinity accelerates the deterioration of the lake aquatic environment. Therefore, sewage and drainage wastewater should be treated before discharging into the lake. The SVMR models based on physiochemical parameters presented the highest performance as an alternative method to predict the WQIs. For example, the calibration (Val.) and the validation (Val.) models performed best in assessing the WQIs with R2 (0.99) and with R2 (0.97–0.99), respectively. Finally, a combination of WQIs, CA, PCA, and SVMR approaches could be employed to assess surface water quality in Qaroun Lake