Biomimetic ZrO2-modified seaweed residue with excellent fluorine/ bacteria removal and uranium extraction properties for wastewater purification

Exploring and developing promising biomass composite membranes for the water purification and waste resource utilization is of great significance. The modification of biomass has always been a focus of research in its resource utilization. In this study, we successfully prepare a functional composite membrane, activated graphene oxide/seaweed residue-zirconium dioxide (GOSRZ), with fluoride removal, uranium extraction, and antibacterial activity by biomimetic mineralization of zirconium dioxide nanoparticles (ZrO2 NPs) on seaweed residue (SR) grafted with oxidized graphene (GO). The GOSRZ membrane exhibits highly efficient and specific adsorption of fluoride. For the fluoride concentrations in the range of 100-400 mg/L in water, the removal efficiency can reach over 99 %, even in the presence of interfering ions. Satisfactory extraction rates are also achieved for uranium by the GOSRZ membrane. Additionally, the antibacterial performance studies show that this composite membrane efficiently removes Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA). The high adsorption of F- and U(VI) to the composite membrane is ascribed to the ionic exchange and coordination interactions, and its antibacterial activity is caused by the destruction of bacterial cell structure. The sustainability of the biomass composite membranes is further evaluated using the Sustainability Footprint method. This study provides a simple preparation method of biomass composite membrane, expands the water purification treatment technology, and offers valuable guidance for the resource utilization of seaweed waste and the removal of pollutants in wastewater.

A correlational study of uranium in groundwater with other physicochemical parameters using GIS mapping in Godda district of Jharkhand, India

The present research concentrates on the cumulative use of GPS and GIS technologies, which are excellent resources for analyzing and monitoring divergent physicochemical parameters in groundwater, including pH, TDS, EC, ORP, Ca+2, Mg+2, NO3-, F-, SO4-2, Cl- and PO4-3 with explicit regard to uranium. Garmin GPS is used to record the locations of the sampling points in the Godda study area. The research aims to offer a thorough understanding of the relationship between soil and water, its impact on public health and the extent to which water can be used in various ways based on its quality. Utilizing the inverse distance weighted (IDW) technique, it is examined how these groundwater parameters and the Water Quality Index (WQI) can be estimated spatially. Additionally, a correlation analysis of the water quality parameters is computed to estimate the local population's cancer risk living in the study area. Except for calcium and magnesium, which are present in excess concentrations throughout the study area with the highest values of 325 and 406 mg/l, respectively at Amediha and Meherma, the results showed that the maximum concentration parameters are within limits with the standard. The main reason might be the area's predominance of Alfisol soil type. The radioactive element uranium is found to be in a limited  range. Chemo-toxicity and radiological risk assessment of the whole area lie far below the restricted cancer risk limit i.e., 30 ppb with the highest concentration of 14 ppb in the 'Sunderpahari' region, following the results obtained. The WQI for the area ranges from 'good' to 'very poor.' The results were favorable but a few sites such as 'Boarijor' and its surroundings, require additional attention to enhance groundwater quality. Given uranium's low availability in groundwater the region's cancer risk assessment is below average.

Waterborne uranium causes toxic effect and thyroid disruption in zebrafish larvae

Uranium is a radioactive element that is widely present in aquatic environment. However, limited knowledge is available about the effect of uranium on thyroid system, which plays a key role in the development of animals. In this study, zebrafish embryos were exposed to different environmentally relevant concentrations of uranium (2, 20 and 100 μg/L) for 120 h. The bioaccumulation, developmental toxicities, changes of thyroid hormones (THs) and key genes related to the hypothalamic-pituitary-thyroid (HPT) axis in larvae were analyzed after exposure. Results showed that uranium could bioaccumulate in zebrafish larvae, with the bioconcentration factors ranging from 49.6 to 523. Consequently, significant developmental toxicities and changes in locomotor activities were observed with a concentration-dependent manner. The levels of triiodothyronine (T3) levels in larvae were substantially decreased, whereas those of thyroxine (T4) were increased in fish bodies. The levels of THs were regulated by the negative feedback loops through HPT axis related genes, most of which (NIS, Deio1, Deio2, TRα, TSHβ and UGT1ab) were significantly depressed after exposure to uranium. Our results suggest the potential toxicities and thyroid disruption of uranium on zebrafish, which would provide baseline data set for better understanding the impact of waterborne uranium on aquatic organisms and the associated mechanisms. This study also highlights the key role of thyroid disruption in the ecological risk assessment of uranium pollution.