Coastal areas may be impacted by human and industrial activities, including contamination by wastewater, heavy metals and hydrocarbons. This study aimed to evaluate the impact of hydrocarbons (TPH) and metals on the microbiota composition and abundance in two estuarine systems in the coast of São Paulo: the Santos (SE) and Itanhaém (IE) estuaries. The SE was found to be chronically contaminated by heavy metals and highly contaminated by hydrocarbons. This finding was correlated with the increased density of cyanobacteria in sediments and suggests the possible use of cyanobacteria for bioremediation. These contaminants influence the density and composition of estuarine microbiota that respond to stress caused by human activity. The results are troubling because quantitative and qualitative changes in the microbiota of estuarine sediments may alter microbiological processes such as decomposition of organic matter. Moreover, this pollution can result in damage to the environment, biota and human health.

Chidiyatappu Bay is one of the least disturbed marine environments of Andaman & Nicobar Islands, the union territory of India. Oceanic flushing from southeast and northwest direction is prevalent in this bay. Further, anthropogenic activity is minimal in the adjoining environment. Considering the pristine nature of this bay, seawater samples collected from 12 sampling stations covering three seasons were analyzed. Principal Component Analysis (PCA) revealed 69.9% of total variance and exhibited strong factor loading for nitrite, chlorophyll a and phaeophytin. In addition, analysis of variance (ANOVA-one way), regression analysis, box-whisker plots and Geographical Information System based hot spot analysis further simplified and supported multivariate results. The results obtained are important to establish reference conditions for comparative study with other similar ecosystems in the region.

Bottlenose dolphins (Tursiops truncatus) inhabiting the Indian River Lagoon, FL (IRL) have tissue mercury concentrations among the highest reported worldwide. Analysis of total mercury (THg) concentrations in blood collected between 2003 and 2012 showed a significant linear decrease over time (p=0.04). Significant differences in the spatial distribution of THg in resident IRL dolphins were also observed with a general gradient in concentration from north to south. Evaluation of local biogeochemistry and accumulation of mercury in prey species is needed to better understand factors influencing the distribution of Hg in the apex predator. Analyses of temporal and spatial patterns of exposure to THg in this sentinel species may have implications for both ecosystem and public health in the region.

Forty-three surface sediment samples and one gravity core obtained from the offshore area of the Changjiang River were analyzed for selected heavy metals (Cu, Pb, Zn, Cd, As, Hg) to evaluate the spatial distribution and potential ecological risk during the last century. The results indicated that the sediments are composed of silty sand, sandy silt and silt and were deposited in a relatively stable environment over the last century. The studied marine sediments are fine and easily adsorb heavy metals from aquatic systems. The heavy metal concentrations were found to be enriched in the sediments and were generally closely related to anthropogenic activities. However, the data analysis demonstrated that the levels of heavy metal contamination were below background values during the last century, indicating low ecological risk. Spatially, a higher concentration was found at the entrance to the Changjiang River, while it decreased to the northeast. The vertical distribution of contamination levels and ecological risk can be divided into four periods based on the downcore variation in heavy metals: pre-1940s, 1940s–1970s, 1970s–1990s and the late 1990s to the present. These conclusions form the basis for implementing appropriate policies to protect marine sediment quality.

Total concentrations and chemical forms of heavy metals in surface sediments of Maluan Bay were determined and multiple geochemical indices and guidelines were applied to assess potential contamination and environmental risks. Metal concentrations exhibited significant spatial variation and the speciation of Cr was presented dominantly in the residual fraction, while Cd was found mostly in the non-residual fraction and thus of high potential bioavailability. Cluster analysis separated four subgroups of sampling sites with different levels of contamination. Further, a multivariate method offered the specific interpretation of possible contaminant sources and/or pathways. Factor scores characterized the sampling locations and elucidated the pollution status, pointing out the impact of multiple “hidden hotspots” of contaminants and providing further evidence of the existence of clear pollution-risk gradients in lagoon areas. The study supports the integrative approach as powerful tool to diagnose the pollution status scientifically for management decisions in coastal sediment of complex environment.

We provide the first report on trace element concentrations in eggs of common eiders (Somateria mollissima), a coastal benthic foraging sea duck, from Nova Scotia, Canada, and compare those to known values from this species elsewhere. Most trace elements of toxicological concern (Hg, Se, Cd, Cu, Zn) were lower in eider eggs from Nova Scotia than from eider eggs collected farther north in Canada, although As was elevated. Our data provide strong support for a pattern of increasing Hg at higher latitudes for this species.

Abundance and composition of anthropogenic marine debris were assessed on the basis of six bottom trawl surveys conducted on the continental slope off Iwate Prefecture, Pacific coast of northern Japan, in 2003, 2004 and 2011, and the temporal changes due to the Tohoku earthquake and tsunami in March 2011 evaluated. In 2003 and 2004, 54–94 items km−2 of marine debris, dominated by sea-base sourced items mainly comprising fishing gear and related items from adjacent fishing grounds on the continental shelf, were quantified. In the post-earthquake period, the density increased drastically to 233–332 items km−2, due to an increase in land-base sourced items generated by the tsunami. However, a major increase in abundance after the disaster, compared to the total amount of tsunami debris swept into the sea, was not found. Additional sources of land-based debris from the adjacent continental shelf are suggested in the present waters.

Near-road measurements for nitrogen dioxide (NO2) using passive air samplers were collected weekly in traffic exposure zones (TEZs) in the Research Triangle area of North Carolina (USA) during Fall 2014. Land use regression (LUR) analysis and pairwise comparisons of TEZs showed NO2 concentrations were associated with TEZs. Greater NO2 levels occurred in delay, high volume, and bus route sections versus higher signal light density, urbanized, and “remainder of study” areas. Comparison of near-road passively sampled NO2 concentrations by TEZ agreed with previous real-time on-road comparisons for NO2 in these TEZs.

Hydrogen sulfide generated in eutrophic marine sediment is harmful for living organisms. It is therefore necessary to remove hydrogen sulfide from the sediment to restore benthic ecosystems. Previous studies revealed that granulated coal ash, which is a by-product of coal thermal electric power stations, could remove and oxidize hydrogen sulfide. In this study, we propose a simplified simulation model to estimate the hydrogen sulfide removal efficiency of granulated coal ash. Hydrogen sulfide concentrations in eutrophic marine sediment pore water with and without the application of granulated coal ash were calculated by the proposed model, and the outputs were compared with semi-field or field observation data. The model outputs reproduced the observed data well. Using the proposed model outputs, we suggest an optimum application dosage of granulated coal ash for remediating eutrophic marine sediment.

Antibiotic use is a well-described practice to promote animal health whether for prevention or treatment. Nonetheless, it can also cause a number of potentially harmful effects that dictate the need to implement regulation to assure a reduction of hazards to the consumers and the environment. Chloramphenicol (CAP) is a broad-spectrum antibacterial excluded from use in animal food production but despite this, reports of illegal use still persist. More recently, awareness has risen that the surrounding natural ecosystems can potentially be contaminated by pharmaceuticals and the extent of their effects in non-target organisms is already under the scope of researchers. To face the demanding new challenges a methodology for the determination of CAP in the green macroalgae Ulva lactuca by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed, optimized and fully validated following the guidelines of the EC Decision 2002/657.