This study aims at describing and interpreting concentrations of arsenic (As), mercury (Hg) and vanadium (V) in seven species of fish, three species of shellfish, one species of crab and two species of shrimp from the typical estuary-bay ecosystem. Arsenic, Hg and V differed among species, and the highest As, Hg and V were observed in shellfish. The stable nitrogen (δ15N) and carbon (δ13C) isotopes were determined to investigate the trophic interactions between fluctuating environment and aquatic species. Arsenic concentrations in samples were found negatively correlated with δ15N, implying biodilution effect of As through the food web, while Hg concentrations in samples were positively correlated with δ15N, indicating their biomagnification effect. The estimated daily intake values of Hg and V in this study were all below the oral reference dose. However, elevated As intakes of some aquatic organisms suggested a potential risk for frequent consumers.

This paper reports baseline levels of litter (macro, meso and microplastics) in sediments collected from different areas of the Croatian MPA of the Natural Park of Telaščica bay (Adriatic Sea, GSA n. 17). The distribution of total abundance according to size, for all analysed locations evidences that microplastics are the dominant fraction concerning item's numbers. In all analysed samples no macroplastics were found, while microplastics are 88.71% and mesoplastics are 11.29% of the total.

From 1861 to the 1940s, gold was produced from 64 mining districts in Nova Scotia, where mercury amalgamation was the dominant method for the extraction of gold from ore until the 1880s. As a result, wastes (tailings) from the milling process were contaminated by mercury and were high in naturally occurring arsenic. In 2004 and 2005, sediments, water and mollusc tissues were collected from 29 sampling stations at nine former gold mining areas along the Atlantic coastline and were analysed for arsenic and mercury. The resulting data were compared with environmental quality guidelines. Samples indicated high potential risk of adverse effects in the intertidal environments of Seal Harbour, Wine Harbour and Harrigan Cove. Arsenic in Seal Harbour was bioavailable, resulting in high concentrations of arsenic in soft-shell clam tissues. Mercury concentrations in tissues were below guidelines. This paper presents results of the sampling programs and implications of these findings.

The dearth of long-time series hampers the measurement of the ecosystem change that followed the global marine climate shift of the 1980–90s. The sessile communities of Portofino Promontory reefs (Ligurian Sea, NW Mediterranean) have been discontinuously studied since the 1950s. Collating information from various sources, three periods of investigations have been distinguished: 1) 1950–70s; 2) 1980–90s; 3) 2000–10s. A cooler phase in time 1 was followed by a rapid warming in time 2, to stabilize at about 0.5°C higher in time 3. Human pressure grew impressively, especially after the establishment of a MPA in 1999. Multivariate analyses evidenced a major change of community composition in time 2. Some species disappeared or got rarer, many found refuge at depth, and among the newcomers there were recently introduced alien species. This study demonstrated the importance of descriptive historical data to understand magnitude and pattern of change in the long term evolution of marine ecosystems.

Contamination of sandy beaches of the Baltic Sea in Kaliningrad region is evaluated on the base of surveys carried out from June 2015 to January 2016. Quantity of macro/meso/microplastic objects in the upper 2cm of the sandy sediments of the wrack zone at 13 sampling sites all along the Russian coast is reported. Occurrence of paraffin and amber pieces at the same sites is pointed out. Special attention is paid to microplastics (range 0.5–5mm): its content ranges between 1.3 and 36.3 items per kg dry sediment. The prevailing found type is foamed plastic. No sound differences in contamination are discovered between beaches with high and low anthropogenic load. Mean level of contamination is of the same order of magnitude as has been reported by other authors for the Baltic Sea beaches.

Being the most reactive of all chemical elements and the lightest member of halogen group, fluorine is found in the environment as fluoride. Both natural and anthropogenic activities are responsible for fluoride contamination in groundwater. Fluoride has dual effect on human health. While lower concentration (<0.5 mg/L) is responsible for dental fluorosis, higher concentration (>1.5 mg/L) leads to skeletal fluorosis and even death. The present review paper is aimed at providing detailed occurrence of fluoride pollution around the globe and in India. Among the different defluoridation techniques to remove excess fluoride from contaminated drinking water at both community and domestic levels, adsorption is found to be very effective due to its technical feasibility, simple characteristics and comparative low-cost nature. Various adsorbents have been tested for their ability to treat fluoride contaminated water, viz., activated carbon, activated alumina, soil, clay and a variety of waste materials. Since fluoride pollution of drinking water is a major concern of poor people as they cannot afford to spend on purification of water, usage of low-cost natural mineral (natural mineral) as adsorbent for fluoride removal is one of the most essential issues in modern era. The present review bestows a detailed discussion on natural mineral as adsorbent used in defluoridation process with special emphasis on soil and low-cost clay minerals.

This study focused on whistles produced by Guiana dolphin under different noise conditions in Guanabara Bay, southeastern Brazil. Recording sessions were performed with a fully calibrated recording system. Whistles and underwater noise levels registered during two behavioral states were compared separately between two areas. Noise levels differed between the two areas across all frequencies. Whistle duration differed between areas and was negatively correlated with noise levels. Whistling rate was positively correlated with noise levels, showing that whistling rate was higher in noisier conditions. Results demonstrated that underwater noise influenced Guiana dolphin acoustic behavior.

Many people practice open defecation in south Asia. As a result, lot of human waste containing nutrients such as nitrogen (N) and phosphorus (P) enter rivers. Rivers transport these nutrients to coastal waters, resulting in marine pollution. This source of nutrient pollution is, however, ignored in many nutrient models. We quantify nutrient export by large rivers to coastal seas of Bangladesh, India and Pakistan, and the associated eutrophication potential in 2000 and 2050. Our new estimates for N and P inputs from human waste are one to two orders of magnitude higher than earlier model calculations. This leads to higher river export of nutrients to coastal seas, increasing the risk of coastal eutrophication potential (ICEP). The newly calculated future ICEP, for instance, Godavori river is 3 times higher than according to earlier studies. Our modeling approach is simple and transparent and can easily be applied to other data-poor basins.

Marine pollution by metals has been a major challenge for ecological systems; however, water quality criteria (WQC) for metals in saltwater is still lacking. Especially from a regulatory perspective, chronic effects of metals on marine organisms should receive more attention. A quantitative ion characteristic–activity relationships–species sensitivity distributions (QICAR-SSD) model, based on chronic toxicities for eight marine organisms, was established to predict the criteria continuous concentrations (CCCs) of 21 metals. The results showed that the chronic toxicities of various metals had good relationships with their physicochemical properties. Predicted CCCs of six metals (Hg2+, Cu2+, Pb2+, Cd2+, Ni2+ and Zn2+) were in accordance with the values recommended by the U.S. EPA, with prediction errors being less than an order of magnitude. The QICAR-SSD approach provides an alternative tool to empirical methods and can be useful for deriving scientifically defensible WQC for metals for marine organisms and conducting ecological risk assessments.

We examined prey selection and foraging behaviors of the crab Charybdis japonica exposed to four combinations of pH (7.3 and 8.1) and temperature (18°C and 25°C). The order of prey selection by C. japonica was Potamocorbula laevis, Ruditapes philippinarum, Tegillarca granosa and Mactra veneriformis. Under high pCO2, times for searching, breaking, eating and handling were all significantly longer than those at the normal pCO2, and the prey profitability and predation rate under high pCO2 were significantly lower than normal pCO2. Moreover, temperature significantly influenced the foraging behaviors, but its effects were not as strong as those of pH; times for searching, eating and handling under high temperature were significantly lower than the low temperature, and the prey predation rates under high temperature was significantly higher than low temperature. In conclusion, high pCO2 negatively affected the foraging behavior, but high temperature actively stimulated the foraging behaviors of crabs.