Persistent Organic Pollutants in gull eggs of two species (Larus michahellis and Larus audouinii) from the Ebro delta Natural Park

The aim of this study was to determine the impact of priority and emerging Persistent Organic Pollutants (POPs) in gull eggs from two species, the scavenger Larus michahellis and the protected species, Larus audouinii. These two species share habitat in the Natural Park of the Ebro delta (Catalonia, Spain). Compounds studied are included or under consideration in the Stockholm Convention and comprise polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated compounds (OCs), perfluorinated compounds (PFCs) and short chain chlorinated paraffins (SCCPs). Four methods based in selective extraction and gas or liquid chromatography coupled to mass spectrometry were used and quality parameters are provided. OC pesticides and marker PCBs were the most abundant chemical families detected in eggs from the two species, followed by PFCs, PBDEs (especially BDE 209) and SCCPs. Dioxin-like PCBs and PCDD/Fs were also detected in all samples. The overall widespread presence of POPs is discussed in terms of feeding habits, bird ecology and anthropogenic pressures in the protected Ebro delta breeding area.     

The size distribution of organic carbon in headwater streams in the Amazon basin

Despite the strong representativeness of streams in the Amazon basin, their role in the accumulation of coarse particulate organic carbon (CPOC), fine particulate organic carbon (FPOC), and dissolved organic carbon (DOC) in transport, an important energy source in these environments, is poorly known. It is known that the arboreal vegetation in the Amazon basin is influenced by soil fertility and rainfall gradients, but would these gradients promote local differences in organic matter in headwater streams? To answer this question, 14 low-order streams were selected within these gradients along the Amazon basin, with extensions that varied between 4 and 8 km. The efficiency of the transformation of particulate into dissolved carbon fractions was assessed for each stream. The mean monthly benthic organic matter storage ranged between 1.58 and 9.40 t ha^?1 month^?1. In all locations, CPOC was the most abundant fraction in biomass, followed by FPOC and DOC. Rainfall and soil fertility influenced the distribution of the C fraction (p?=?0.01), showing differentiated particulate organic carbon (POC) storage and DOC transportation along the basin. Furthermore, the results revealed that carbon quantification at the basin level could be underestimated, ultimately influencing the global carbon calculations for the region. This is especially due to the fact that the majority of studies consider only fine particulate organic matter and dissolved organic matter, which represent less than 50 % of the stored and transported carbon in streambeds.     

Indoor pollutant exposure among children with and without asthma in Porto,Portugal, during the cold season

Environmental Science and Pollution Research - Considering the time spent in enclosed spaces, indoor air pollutants are of major interest because of its possible impact on health. However, to date,...     

Uptake and depuration of anatoxin-a by the mussel Mytilus galloprovincialis (Lamarck, 1819) under laboratory conditions

Cyanobacterial blooms tend to be more common in warm and nutrient-enriched waters and are increasing in many aquatic water bodies due to eutrophication. The aim of this work is to study the accumulation and depuration of anatoxin-a by Mytilus galloprovincialis a widespread distributed mussel living in estuarine and coastal waters and recognized worldwide as a bioindicator (e.g. Mussel Watch programs). Research on the distribution and biological effects of anatoxin-a in M. galloprovincialis is important. Nevertheless, the risk of human intoxication due to the consumption of contaminated bivalves should also be considered. A toxic bloom was simulated in an aquarium with 5 x 10(5) cell ml(-1) of Anabaena sp. (ANA 37), an anatoxin-a producing strain. Mussels were exposed to Anabaena for 15 days and then 15 days of depuration followed. Three or more animals were sampled every 24h for total toxin quantification and distribution in soft tissues (edible parts). Water samples were also taken every 24h in order to calculate total dissolved and particulate anatoxin-a concentrations. Anatoxin-a was quantified by HPLC with fluorescence detection. No deaths occurred during accumulation and depuration periods. One day after the beginning of depuration, the toxin could not be detected in the animals. Anatoxin-a is distributed in the digestive tract, muscles and foot and is probably actively detoxified.