The economic development of a country is mainly dependent on important industrial activities such as mining. Because of mining operations, huge quantities of solid wastes especially, overburden and rejects, are generated. As these are not valuable to the owners of the mine, they may be inappropriately disposed of into the environment, posing severe threat to the environment, particularly affecting both surface and ground water quality. Most mine waste-related environmental degradation is associated with leaching of contaminants from overburden dumps and acid mine drainage. Leachates originating from mine waste overburden dumps may have the potential to contaminate the surrounding water resources, especially ground water. The present paper envisages the harmful effect of mine waste leachates on the environment and how it creates possible hazard to aquatic life. This paper also reviews the strategies for improvements in existing mine waste management along with the suitable measures to combat the overall problem.

Elevation in toxic trace metal concentration found in coastal sediments in recent years (2013–2016) increased the risk to the aquaculture industry in south Hangzhou bay. This study assessed the main factors controlling the metal distribution and mobility in sediments by sampling from 20 sites along the bank. Spatial distribution and cluster analysis indicated that Cd, As, Hg and Sb attributed to anthropogenic terrestrial sources; while Cr, Co, Cu, Ni, Zn, and Pb, carried by fine-grained sediments and accumulated on tidal flat, were inputted from marine sources. High mobility of Cd was expected because of its considerable proportion (~50%) associated with the acid extractable fraction. Pb, Cu and Co in redox sensitive fraction should also be taken into concern in management of reclaimed area affected by tide. Risk assessments by potential ecological risk index (PERI) emphasised the importance of further monitor and proper treatment of 4 terrestrial generated metals in sediments.

Spatial distribution and potential ecological risk of trace metals in the surface sediment of south east coast of India covering eight different ecosystems was studied. The concentration of major elements viz. Ca, Mg, K, Ti and trace metals viz. Cr, Mn, Co, Al, Fe, Ni, Cu, Zn, Cd and Pb were analysed by energy dispersive X-ray fluorescence technique. Contamination factor, geo-accumulation index, probable effect level, enrichment factor and pollution load index were calculated to evaluate the pollution status. Except cadmium, CF values for all the metals ranged between 1≤CF≤3 indicating moderate metal contaminations along the coast. Mean PEL quotient (Qm-PEL) indicated toxicity probability to be below 21%. Fe, Cu, Zn and Co showed significant positive correlation (p<0.01) with clay. Chromium was the only metal that demonstrated strong negative correlation with clay (p<0.01) and positive correlation (p<0.01) with sand content.

Spatial and temporal patterns of coastal microbial pollution are not well documented. Our study examined these patterns through measurements of fecal indicator bacteria (FIB), nutrients, and physiochemical parameters in Hilo Bay, Hawai'i, during high and low river flow. >40% of samples tested positive for the human-associated Bacteroides marker, with highest percentages near rivers. Other FIB were also higher near rivers, but only Clostridium perfringens concentrations were related to discharge. During storms, FIB concentrations were three times to an order of magnitude higher, and increased with decreasing salinity and water temperature, and increasing turbidity. These relationships and high spatial resolution data for these parameters were used to create Enterococcus spp. and C. perfringens maps that predicted exceedances with 64% and 95% accuracy, respectively. Mapping microbial pollution patterns and predicting exceedances is a valuable tool that can improve water quality monitoring and aid in visualizing FIB hotspots for management actions.

A comprehensive review is reported on the extent of release of ultrafine and nanoparticles from vehicular exhaust on Indian roads, the mechanism of evolution of these particles and the influence of key fuel and meteorological parameters on their evolution and dispersion. Consolidated understanding developed based on the available literature on nanoparticle formation and transformation processes is presented pictorially in the form of a schematic diagram. Influence of various parameters on the evolution of nanoparticles is elaborated using the present scientific understanding of dispersion mechanisms in the near and far field of vehicular exhausts. Inferences are drawn for the influence of Indian road conditions and atmospheric conditions on the dispersion of these evolved nanoparticles. Broad based suggestions are outlined for the Indian regulatory authorities so as to minimize the hazardous influence of such particulate emissions to urban population.

The drivers behind microplastic (up to 5mm in diameter) consumption by animals are uncertain and impacts on foundational species are poorly understood. We investigated consumption of weathered, unfouled, biofouled, pre-production and microbe-free National Institute of Standards plastic by a scleractinian coral that relies on chemosensory cues for feeding. Experiment one found that corals ingested many plastic types while mostly ignoring organic-free sand, suggesting that plastic contains phagostimulents. Experiment two found that corals ingested more plastic that wasn't covered in a microbial biofilm than plastics that were biofilmed. Additionally, corals retained ~8% of ingested plastic for 24h or more and retained particles appeared stuck in corals, with consequences for energetics, pollutant toxicity and trophic transfer. The potential for chemoreception to drive plastic consumption in marine taxa has implications for conservation.

Major and trace metal concentrations were determined in western Adriatic sediment cores. Based on sediment chronology, the earliest anthropogenic influence appeared as a Zn and Pb increase in the Po River prodelta starting from ~1914. The increasing contamination signal of these trace metals propagated southward as far as 450km with a growing delay, taking ~10years to reach the south Adriatic Sea. Although greater inventories of excess trace metals in the northern sector pointed to the influence of the intense human activities in the Po River drainage basin and Venice lagoon system, we observed a reduction of excess trace metals from mid-1980s, related to the implementation of stricter environmental regulations on chemical wastewaters. In contrast, an increase in trace metal accumulation in surficial sediment from the 2000s in front of the cities of Ancona and Bari suggested a recent local input of trace metals, probably due to harbor activities.

The environmental quality differences between two groups of reefs in the Veracruz Reef System were evaluated. The North group of reefs is very close to Veracruz, an urban and port zone, whereas the South group is more isolated, with minor anthropogenic disturbances. To prove the hypothesis that the North group is more affected by anthropogenic activities, the concentrations of hydrocarbons in liver, metals and metalloids such as Se, As, Ba, Cd, Hg and V in muscle, and PAH metabolites in bile were evaluated, and related to biomarkers (transcript abundance of cytochrome P4501A, Vitellogenin, and Glutathione-S-transferase) in two species of fish: Haemulon aurolineatum and Ocyurus chysurus. H. aurolineatum presents the highest concentrations for many pollutants, but O. chysurus shows the most significant differences in pollutant concentrations and biomarkers between the two reef groups, suggesting that this species could be used as a sentinel in future studies in the Gulf of Mexico.

Mangrove sediment harbors a unique microbiome and is a hospitable environment for a diverse group of bacteria capable of oil biodegradation. Our goal was to understand bacterial community dynamics from mangrove sediments contaminated with heavy-oil and to evaluate patterns potentially associated with oil biodegradation is such environments. We tested the previously proposed hypothesis of a two-phase pattern of petroleum biodegradation, under which key events in the degradation process take place in the first three weeks after contamination. Two sample sites with different oil pollution histories were compared through T-RFLP analyses and using a pragmatic approach based on the Microbial Resource Management Framework. Our data corroborated the already reported two-phase pattern of oil biodegradation, although the original proposed explanation related to the biophysical properties of the soil is questioned, opening the possibility to consider other plausible hypotheses of microbial interactions as the main drivers of this pattern.

In order to evaluate trace element bioavailability and potential transfer into marine food chains in human impacted areas of the Fildes Peninsula (King George Island, South Shetland Islands Archipelago), element levels (Cr, Ni, Cu, Zn, Cd, and Pb) were determined in water, sediments, phytoplankton, and in diatom Phaeodactylum tricornutum Bohlin (Bacillariophyceae) cells immobilised in alginate and exposed to water and sediments, from the Bellingshausen Dome (reference site) and Ardley Cove (human impacted area), during January 2014. High element concentrations in exposed P. tricornutum indicated element mobilisation from sediments into the water. Levels in exposed cells reflected the sediment element content pattern, comparable to those found in phytoplankton, supporting phytoplankton as an important path of trace element entry into marine food chains. This study clearly shows immobilised P. tricornutum as good proxy of phytoplankton concerning element accumulation efficiency, and an effective tool to monitor trace element contamination in polar coastal ecosystems.