Mercury assessment in the marine environment: assessment criteria comparison (EAC/EQS) for mercury

Mercury is known for its worldwide environmental impact. It is addressed by several existing international agreements addressing atmospheric emissions (CLRTAP), the marine environment (OSPAR, HELCOM, Barcelona, Bucharest), waste (Basel), and export of chemicals (Rotterdam). It can be brought into the biosphere by humans by two different mechanisms: 1) intentional extraction and use, and 2) as a natural constituent in other materials. Mercury is extremely toxic to both man and biota and can be transformed within the aquatic environment into more toxic organic compounds (e.g. methyl mercury). A main pathway of mercury to the sea is atmospheric and it can be carried long distances from its source. The primary risk to the general population is exposure to methylmercury via ingestion of aquatic foods. OSPAR measures and subsequent EU measures regulate the main industrial sources for mercury releases to the environment. A suite of OSPAR measures control mercury emissions, discharges and sources. OSPAR has promoted actions in other international forums, especially the EU, e.g. call for actions to prevent pollution from the disposal of large amounts of pure and waste mercury arising from the closure or conversion of mercury cell chlor-alkali plants and for control measures on the use and marketing of mercury in various products

Trace elements: critical insights from 15 years of monitoring in the Venice Lagoon catchment basin (Italy)

The study focused on selected trace elements (As, Cd, Cr, Hg, Ni, Pb) monitored in surface waters of the Venice Lagoon catchment basin (North East Italy) over the period 2000-2015. The monitoring was undertaken to verify the achievement of the quality objectives set by the European and national legislations. The available results have been analyzed to evaluate the chemical status of water bodies. The limit of quantification (LOQ) of the applied analytic techniques appears critical for the adequate water monitoring; for some parameters, the percentage of not visible values due to non-satisfactory LOQ was higher in the beginning of the period; the subsequent improvement of LOQ allowed assessing the respect of environmental quality standards (EQSs). The study analyzes time trends in single stations and the differences between detected concentrations in the considered stations. Moreover, maximum concentrations and water flows have been considered to understand the potential correlation. Cumulated frequency curves for the most critical parameters have been built to identify situation of potential overtaking of the EQSs in force. The most polluted sampling stations of the drainage basin for the six trace elements were found in Cuori and Fiumazzo rivers. Although LOQs changed over time, the recorded trends show a quality improvement and a good compliance with respect to EQSs set by European legislation, while considering EQSs set by local special legislation, the objectives are not yet satisfied. Arsenic is ubiquitous; thus, it can be supposed to be originated as a background environmental concentration, while nickel appears of industrial origin according to its point and local presence

Levels and trends of brominated flame retardants in the European environment

In this paper, we review those data which have recently become available for brominated flame retardants (particularly the brominated diphenyl ethers (BDEs) and hexabromocyclododecane (HBCD)) in samples from the European environment. Environmental compartments studied comprise the atmosphere, sediments and soils, sewage sludges, and a variety of biological samples and food chains. This is currently a very active research area, and we cite over 70 studies reported in the literature during 2003¿04. Findings include that the input of BDEs (especially BDE209) to the Baltic Sea by atmospheric deposition now exceeds that of PCBs by a factor of almost 40 times. Sewage sludge samples from both industrial and background locations show concentrations of BDEs, HBCD and tetrabromobisphenol-A (TBBP-A) that are of a similar order, indicating that the major source is from diffuse leaching from products into wastewater streams from users, households and industries generally. Point-sources from industries using BFRs (e.g. the textile industry) also generate local hot-spots. Sediment core studies identified the presence of two of the three PBDE formulations. The penta-mix formulation was clearly present from the beginning of the 1970s, but the deca-mix only appeared in the late 1970s. BDE183, BDE209 and HBCD were detected in peregrine falcons from Sweden and other birds feeding on terrestrial food chains. BDEs are found widely distributed in fish, including those from high mountain lakes in Europe, as a consequence of long-range atmospheric transport and deposition. A temporal trend study in archived freeze-dried mussels from the Seine estuary, France, indicated an exponential increase in BDE concentrations during the period 1982¿1993, which levelled off in 1999 and 2001 and then began to decline after 2002. HBCD was detected in liver and blubber samples from harbour seals and harbour porpoises from the Wadden and North Seas, though very few animals yielded positive values for TBBP-A. There are difficulties in comparing data on ¿BDE from studies in which different suites of BDE congeners have been determined, and we suggest a common suite which will allow the study of all three commercial PBDE formulation