Rajasthan is one of the main mineral potential state of India. During the last 30 years it has witnessed enormous expansion of mining industries, but mining of most of the minor minerals coupled with changing climate has posed serious problems to the environmental fabric in the state, apart from base metal beneficiation plants. Groundwater is also being polluted day-by-day by effluents generated from mineral wastes and beneficiation processes in the vicinity of mining sites such as Khetri. Pollutant concentrations were measured in groundwater at the vicinity of Khetri copper mining project, Rajasthan to investigate the influence of copper mining on environment. Pollutant concentrations in groundwater were investigated. Copper metal concentration in water samples were found above the maximum desirable limit in two sources: G4 and G5, due to washing away of mineral with water. Mining industry has deteriorated quality of groundwater resources in the state of Rajasthan, and these industries are becoming centers of pollution sources which need timely actions at government level so that natural resources such as groundwater can be protected.

The development of a surface water evaluation index is a critical factor in the assessment, restoration and protection of stream water quality. Quantifying water pollution in specific grade using dominant parameters is important, as this can explain the current state of water pollution with accuracy. As a result, an integrated multi-parameter water quality index has been developed. It is based on the 10 most prevailing parameters (pH, conductivity, nitrate ions, phosphate ions, Escherichia coli number, cadmium, chromium, lead, copper and manganese) with a scale of 1 to 4, wherein the grades are classified into 1: good; 1.1-1.5: slightly polluted; 1.6-2.0: moderately polluted; 2.1-2.9: heavily polluted and 3.0-4.0: gravely polluted. The measuring stick used was according to the 2011 background values of the World Health Organization (WHO) in which a value of 0.1 was attributed for each, so that the final grade can be calculated. Water quality data were successfully fitted in an integrated multi-parameter water quality index to measure the river water level of pollution, and effectively represented every water bodies. This innovative index is able to quantify pollution with respect to seasons, geography and geomorphology of the respective rivers. Although operative, this index still lacks scientific integrity and as such, more synoptic experiments in the rivers of developing countries are recommended to attain a pragmatic feature.

Few studies have assessed social inequalities in exposure to drinking water contaminants. This study explores this issue in 593 rural municipalities of Québec, Canada. Quartiles of an ecological composite deprivation index were used as a proxy of socioeconomic status. Total trihalomethanes (TTHMs) and lead were chosen as proxies of chemical drinking water quality. The results show that the majority of deprived rural municipalities apply no treatment to their water (26%) or use a basic treatment (51%), whereas a relative majority of the wealthiest municipalities (40%) use advanced treatment. The proportion of municipalities having important lead (>5 μg/L) levels is highest in most deprived municipalities. Moreover, most deprived municipalities have a higher risk of high tap lead levels (RR = 1.33; 95%CI: 1.30, 1.36). Conversely, most deprived municipalities have a lower risk of high TTHMs levels (RR = 0.78; 95%CI: 0.69, 0.86). These findings suggest an environmental inequality in drinking water contaminants distribution in rural municipalities.

Excess nitrogen inputs to terrestrial ecosystems via human activities have deteriorated water qualities on regional scales. Urban areas as settlements of over half global population, however, were usually not considered in the analysis of regional water pollution. Here, we used a 72-month monitoring data of water qualities in Hangzhou, China to test the role of urban rives in regional nitrogen pollution and how they response to the changes of human activities. Concentrations of ammonium nitrogen in urban rivers were 3–5 times higher than that in regional rivers. Urban rivers have become pools of reactive nitrogen and hotspots of regional pollution. Moreover, this river pollution is not being measured by current surface water monitoring networks that are designed to measure broader regional patterns, resulting in an underestimation of regional pollution. This is crucial to urban environment not only in China, but also in other countries, where urban rivers are seriously polluted.

The increasing demand for fresh water has forced many countries to use reclaimed wastewater for agricultural purposes. This water contains pharmaceuticals and personal care products (PPCPs) that remain biologically active following passage through wastewater treatment plants. Run-off from farms and contaminated water from treatment facilities exposes aquatic ecosystems to PPCPs. This study examined the effects of PPCPs on a lower trophic organism. Culex quinquefasciatus larvae were reared in water contaminated with environmentally relevant concentrations of common PPCPs. Acetaminophen alone and a mixture of contaminants were found to increase developmental time of larvae. Susceptibility to Bti increased in larvae exposed to antibiotics, acetaminophen, or a mixture of PPCPs. Antibiotics, hormones, and the mixture altered the mosquito bacterial microbiome. Overall, the results indicate that at environmentally relevant concentrations, PPCPs in reclaimed water can have biologically important effects on an ecologically and medically important lower trophic level insect.

Climate projections over the next century include disproportionately warmer nighttime temperatures (“asymmetrical warming”). Cool nighttime temperatures lower metabolic rates of aquatic ectotherms. In contaminated waters, areas with cool nights may provide thermal refugia from high rates of daytime contaminant uptake. We exposed Cope's gray tree frogs (Hyla chrysoscelis), southern leopard frogs (Lithobates sphenocephalus), and spotted salamanders (Ambystoma maculatum) to five concentrations of a mixture of cadmium, copper, and lead under three to four temperature regimes, representing asymmetrical warming. At concentrations with intermediate toxicosis at test termination (96 h), temperature effects on acute toxicity or escape distance were evident in all study species. Asymmetrical warming (day:night, 22:20 °C; 22:22 °C) doubled or tripled mortality relative to overall cooler temperatures (20:20 °C) or cool nights (22:18 °C). Escape distances were 40–70% shorter under asymmetrical warming. Results suggest potentially grave ecological impacts from unexpected toxicosis under climate change.

This study presents a model to assess the oil spill risk in Garorim Bay in Korea, where large-scale oil spill accidents frequently occur. The oil spill risk assessment is carried out by using two factors: 1) The impact probability of the oil spill, and 2) the first impact time of the oil that has been spilt. The risk assessment is conducted for environmentally sensitive areas, such as the coastline and aquaculture farms in the Garorim Bay area. Finally, Garorim Bay is divided into six subareas, and the risks of each subarea are compared with one another to identify the subarea that is most vulnerable to an oil spill accident. These results represent an objective and comprehensive oil spill risk level for a specific region. The prediction of the oil spill spread is based on real-time sea conditions and can be improved by integrating our results, especially when sea conditions are rapidly changing.

The nutrient uptake and release by the mussels in relation with amount of food consumption are emphasised in this research. Results of the study demonstrate that about 16% of the total mass dry weight food consumed by the mussels was released as faeces. The depositions of particulate carbon, nitrogen, and phosphorus in mussel faeces were found to be 26.3, 5.7, and 0.6mg/day/indv respectively. Soluble inorganic nutrients such as NH4+-N (2.5mg/day/indv), and PO43−-P (0.6mg/day/indv) were also released as mussel excretion. The nutrient absorption efficiency for the green mussel body was found to be 65.1% for carbon, 62.1% for nitrogen, and 79.2% for phosphorus. Subsequently, green mussels can remove particulate carbon, nitrogen and phosphorus at 108.1, 13.5, and 4.6mg/day/indv from aquatic systems. Finally, the results can help in estimating the carrying capacity of mussel cultivation without deteriorating the water quality in marine ecosystems.

Development of human activities in the Klaipėda strait generates a wide spectrum of underwater noise. In the fall of 2013, at the liquid natural gas terminal construction site in the shallow Curonian Lagoon area, an assessment of possible negative impacts on migrating salmon fish caused by pile driving noise was made. It is well known that impact hammer pile driving generates pulses with extremely high underwater noise levels. The obtained results proved that the pile hammering into the lagoon bottom generated pulses with a sound exposure level of 218dB re 1μPa2s @1m thus posing a risk to the migrating fish.