This work reports changes in suspended particulate matter, turbidity, dissolved Cr, Ni, Cu, Cd, Hg and Pb concentrations, and phytoplankton biomass and composition during a 5-month period dredging operation, in a trace element contaminated area of the Tagus estuary (Portugal). Phytoplankton biomass, diatom:other groups ratio, benthic:pelagic diatom ratio, Margalef's, Simpson's diversity, Shannon–Wiever's, and Warwick and Clarke's taxonomic diversity and distinctness indices, and individual taxa were investigated as indicators of dredging induced changes. Significant rise in sediment resuspension and trace element mobilisation caused by dredging influenced the community structure but not the overall biomass. Benthic diatom displacement into the water column maintained species diversity, and therefore, none of the indices highlighted community changes. Contrastingly, diatom:other groups ratio and benthic:pelagic diatom ratio were reliable indicators for the assessment of dredging induced changes. A shift in composition towards species less susceptible to trace elements was observed, disclosing some individual taxa as potential indicators.

A whole-cell bacterial bioreporter Acinetobacter baylyi strain ADP1_recA_lux that responds to genotoxins was employed to directly assess the adverse effects of the bioavailable fraction of mitomycin C (MMC), benzo[a]pyrene (BaP), chromium (VI) and lead (II) in amended soils and soil samples from two fragile areas in China without soil pre-treatment. The amended soils containing pollutants with the concentrations as low as 0.4 mg/kg MMC, 0.5 mg/kg BaP, 520 mg/kg Cr (VI) and 2072 mg/kg Pb (II) were found to be toxic. Soil particle-associated pollutants accounted for 86%, 100%, 29%, and 92% of the genotoxicity in the MMC, BaP, Cr (VI), and Pb (II) amended soil, respectively. The soils from contaminated sites were also valid to be genotoxic. The results suggest both free and soil particle-associated pollutants are bioavailable to soil organisms and a solid-phase contact bioreporter assay to soil contamination could provide a rapid screening tool for environmental risk assessment.

We investigated effects of arsenate (AsV), chromate (CrVI) and sulfate on As and Cr uptake and translocation by arsenic hyperaccumulator Pteris vittata (PV), which was exposed to AsV, CrVI and sulfate at 0, 0.05, 0.25 or 1.25 mM for 2-wk in hydroponic system. PV was effective in accumulating large amounts of As (4598 and 1160 mg/kg in the fronds and roots at 0.05 mM AsV) and Cr (234 and 12,630 mg/kg in the fronds and roots at 0.05 mM CrVI). However, when co-present, AsV and CrVI acted as inhibitors, negatively impacting their accumulation in PV. Arsenic accumulation in the fronds was reduced by 92% and Cr by 26%, indicating reduced As and Cr translocation. However, addition of sulfate increased uptake and translocation of As by 26–28% and Cr by 1.63 fold. This experiment demonstrated that As and Cr inhibited each other in uptake and translocation by PV but sulfate enhanced As and Cr uptake and translocation by PV.

This review provides a summary of studies analysing metal concentrations in soils and soil solution at European roadsides. The data collected during 27 studies covering a total of 64 sites across a number of European countries were summarised. Highest median values of Cr, Cu, Ni, Pb, and Zn were determined in the top soil layer at the first 5 m beside the road. Generally, the influence of traffic on soil contamination decreased with increasing soil depth and distance to the road. The concentration patterns of metals in soil solution were independent from concentrations in the soil matrix. At 10-m distance, elevated soil metal concentrations, low pH, and low percolation rates led to high solute concentrations. Directly beside the road, high percolation rates lead to high annual loadings although solute concentrations are comparatively low. These loadings might be problematic, especially in regions with acidic sandy soils and a high groundwater table.

Freshwater aquatic organisms face the challenge of being exposed to a multitude of chemicals discharged by the human population. The objective of this study was to rank metals according to the threat they pose to aquatic organisms. This will contribute to a wider Chemical Strategy for freshwater which will risk-rank all chemicals based on their potential risk to wildlife in a UK setting. The method involved comparing information on ecotoxicological thresholds with measured concentrations in rivers. The bioconcentration factor was also considered as a ranking method. The metals; Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn, were analysed using this approach. Triclosan and lindane were used as comparative organic pollutants. Using a range of ranking techniques, Cu, Al and Zn came top of the list of concern, with Cu coming first.

Surface sediments were collected from five nearshore (wastewater discharges, aquaculture facilities and a seaport) sites in Bohai Bay and Laizhou Bay, China. The equilibrium partitioning (EqP) model and empirical sediment quality guidelines (SQGs) were applied to assess the potential metal toxicity in the collected sediments. The results show that, based on the EqP model, 35% of stations exhibited potential metal toxicity. Several metals (Cu, Ni and Cr) exceeded the empirical SQGs (9–93% of the time), however these guidelines may not be suitable for use in the Bohai Sea owing to the background concentrations. The EqP model is a more useful method for assessing potential metal toxicity in Bohai Sea sediment than the empirical SQGs. Additionally, we have provided new understanding about methods for assessing sediment metal toxicity in the Bohai Sea that may be useful in other coastal areas in China.

No studies document essential (calcium, magnesium, phosphorus, potassium, sodium), trace (barium, boron, chromium, cobalt, copper, iron, manganese, molybdenum, selenium, zinc) or toxic element (antimony, arsenic, cadmium, lead, mercury, thallium) concentrations in any members of the family Molidae, including the world’s largest bony fish, the ocean sunfish (Mola mola). Here, we analyzed 21 elements in the liver of one M. mola. These values were compared to liver concentrations in multiple species with spatial and dietary overlap. Concentrations of calcium (3339ppm wet weight) and iron (2311ppm wet weight) were extremely elevated in comparison to a number of other fish species, indicating that calcium and/or iron toxicity may have occurred in this animal. Concentrations of toxic elements were generally low, with the exception of cadmium (3.5ppm). This study represents the first report of essential, trace and toxic elements in this species.

The degree of pyritization (DOP) and the extension of metals incorporation into pyrite was investigated at Guanabara Bay sediments. Maximum concentrations of total organic carbon (TOC), total sulfur, biopolymers and viable bacteria cells were observed in silted stations close to discharge points of sewage and minimum concentrations at sandy stations at the entrance of the bay. Pyrite iron concentrations (Fepy) was always lower than the reactive iron and Fepy were below the detection limit at sandy stations. The same trend was found to metals, which its degree of pyritization was Mn=Cu>As=Co>Ni>Cd>Zn≫Pb>Cr. The bay gathers all required factors to sulfate reduction and pyrite formation, once the C:S ratio express the reduced tendency conditions, almost half of the TOC present in its sediments is labile and both reactive sulfur and iron are available. However the degree of trace metals pyritization did not exceed 20%, consistent with the median DOP (29%).

The surficial coastal sediments in Kendari Bay are sampled in the field to determine the concentration and pollution level of three heavy metals (Pb, Cd and Cr). Twenty-five sampling points ranging from the inner (Wanggu River) to the outer area of the bay have been chosen. The physicochemical properties, such as temperature, pH, salinity and TDS of the overlying water, as well as the sediment type and TOC of the surficial sediments, are also measured. The total concentrations of the Pb, Cd and Cr in the sediment samples are quantified using inductively-coupled plasma mass spectrometry (ICP-MS). The concentrations of the heavy metals (Pb, Cd and Cr) ranged from 0.84 to 17.02μg/g, 0.02 to 0.17μg/g and 1.92 to 40.11μg/g (dry weight), respectively, following the Cr>Pb>Cd sequence. To assess the degree of contamination, a geoaccumulation index (Igeo) is measured. Kendari Bay is not a contaminated area regarding Pb, Cd and Cr.

The water column from Dakar coast and Saint Louis estuary in Senegal, West Africa, was sampled in order to measure the contamination level by trace metals. The speciation of metals in water allowed performing a distribution between dissolved and particulate trace metals. For the dissolved metals, the metallic concentration and repartition between the organic fraction and the inorganic fraction were performed. The results show that the pollution of the estuary was more serious than in Dakar coast for Co, Cr, Ni, Pb and Zn; while, Cd and Cu were higher in Dakar coast. A strong affinity between metals and suspended particles has been revealed. Dissolved metals that have a tendency to form organic metal complexes are in decreasing order: Cd, Zn, Pb, Co=Cr=Mn, Cu and Ni. The results showed that the mobility of trace metals in estuary is controlled by dissolved organic carbon, while in coast it depends on chlorides.