Development of a black carbon-inclusive multi-media model: application for PAHs in Stockholm

A multi-media model was developed for predicting the fate of organic chemicals in the Greater Stockholm Area, Sweden, and applied to selected polycyclic aromatic hydrocarbons (PAHs). Although urban models have been previously developed, this model is novel in that it includes sorption to pyrogenically-derived particles, commonly termed "black carbon" (BC), within the model structure. To examine the influence of BC sorption on environmental fate of PAHs, two versions of the model were generated and run: one in which sorption to BC was included and one in which BC sorption was excluded. The inclusion of BC sorption did not cause any significant variations to air levels, but it did cause an average 20-30% increase in sediment concentrations related to increased sediment solids partitioning. The model also predicted reduced advective losses out of the model domain, as well as chemical potential to diffuse from sediments, whilst total chemical inventory increased. In all cases, the lighter PAHs were more affected by BC inclusion than their heavier counterparts. We advocate the addition of sorption to BC in future multi-media fate and exposure models, which as well as influencing fate will also alter (lower) chemical availability and, thus, wildlife exposure to hydrophobic chemicals. A quantification of the latter was derived with the help of the soot-inclusive model version, which estimated a lowering of dissolved water concentrations between five and >200 times for the different PAHs of this study.     

Assessment of soils contamination with veterinary antibiotic residues in Northern Poland using developed MAE-SPE-LC/MS/MS methods

Among the wide range of compounds reaching the soil are the veterinary antimicrobials. Since no regulations regarding acceptable levels of drug concentrations in the environment exist, monitoring tests, particularly concerning soils, are carried out very rarely. This study presents a preliminary assessment of the contamination of agricultural soils in Northern Poland with seven antimicrobial veterinary medicines which has never been carried out before. Veterinary drugs were detected in 54% of the examined soil samples; the most commonly detected drugs were sulfonamides and trimethoprim. The highest indicated concentrations refer to enrofloxacin (57.0 μg kg^?1) and trimethoprim (47.8 μg kg^?1). The presence of these target drugs in the soil environment confirms the need for further monitoring studies. The analytical methods developed in this study are an excellent tool to achieve this goal and allow an estimation of the risk connected with the presence of veterinary antimicrobials in soils.

     

Effect of land use changes on non-carcinogenic health risks due to nitrate exposure to drinking groundwater

Environmental Science and Pollution Research - This study aimed to determine the effect of land-use changes on the non-carcinogenic health risk of nitrate ion exposure of underground drinking water...     

Organochlorine pollutants in Scots pine needles--biological and site related variation within a forest stand

To study the biological variation in the content of some persistent organic pollutants, viz hexachlorobenzene (HCB), alpha- and gamma-hexachlorocyclohexane (alpha- and gamma-HCH), and 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane (DDT) were analysed in needles from Scots pine trees growing at an isolated peninsula south of Stockholm, Sweden. The concentration variations of each compound was evaluated by a nested analysis of variance (ANOVA) with sampling site specific compass direction, individual tree, and sampling height as factors. Two pair-wise post hoc tests were used to test significant results from the ANOVA. The hexachlorocyclohexanes showed no significant differences between sampling site, trees or sampling height. DDT concentration was significantly lower at the sampling site with the densest vegetation compared to at least three of the other sampling sites. HCB was significantly lower at the lowest sampling height (0.5 m).     

Blood serum concentrations of perfluorinated compounds in men from Greenlandic Inuit and European populations

Perfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are used in large quantities. They are persistent and found in measurable levels in human serum around the world. They have been associated with developmental, hepatic, and carcinogenic effects in animal studies. The aim of the present study was to describe levels of PFCs in serum among Inuits from Greenland and inhabitants from Warsaw, Poland and Kharkiv, Ukraine. Furthermore, the aim was to define social- and lifestyle related determinants of exposure for these compounds. Serum levels of seven PFCs were analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS). The concentrations of PFOS and PFOA were the highest of all PFCs in all three populations with a total amount of almost 90% of the PFCs. The mean levels of PFOS and PFOA were in the Greenlandic Inuits 52 and 4.8 ng mL(-1), in Poland 19 and 5.2 ng mL(-1), and in Ukraine 8.1 and 1.9 ng mL(-1), respectively. Thus, levels of PFCs in the serum of Inuits on Greenland were among the highest described in a general population whereas the levels in Poland were similar to other industrialized countries. The exposure in Ukraine was rather low. In the Greenlandic Inuit population, intake of seafood, tea, age and area of living were significant determinants of PFOS concentrations and explained about 22% of the variation. For the other populations no strong determinants were found.     

Pollution in coastal fog at Alto Patache,Northern Chile

Background  

The Atacama Desert in Northern Chile is one of the most arid places on earth. However, fog occurs regularly at the coastal mountain range and can be collected at different sites in Chile to supply settlements at the coast with freshwater. This is also planned in the fog oasis Alto Patache (20°49′S, 70°09′W). For this pilot study, we collected fog water samples in July and August 2008 for chemical analysis to find indications for its suitability for domestic use.     

Generator column determination of aqueous solubilities for non-ortho and mono-ortho substituted polychlorinated biphenyls

Aqueous solubilities of four non-ortho and eight mono-ortho substituted PCBs were determined using a generator-column technique followed by subsequent off-line GC/ECD analysis of the aqueous solutions. The method is based on pumping water through a column containing glass beads coated with the congener being studied and has been used to measure solubilities at room temperature. The method circumvents many of the experimental difficulties encountered with the traditional shake-flask system. Aqueous solubility of 3,3′,4,4′-tetrachlorobiphenyl determined by this procedure is compared with data obtained from the shake-flask method and the computational method. The precision of replicate measurements is better than ±6.5%. Aqueous solubilities determined for 12 congeners ranged from 6.07 × 10⁻¹¹ to 4.47 × ⁻⁹ mol/L and generally decreased with molecular weight and increased with degree of ortho-chlorine substitution within a molecular-weight class.     

NAPL migration and ecotoxicity of conventional and renewable fuels in accidental spill scenarios

Fuels derived from non-petroleum renewable resources have raised interest due to their potential in replacing petroleum-based fuels, but information on their fate and effects in the terrestrial and aquatic environments in accidental spill scenario is limited. In this study, migration of four fuels (conventional diesel, conventional gasoline, renewable diesel NExBTL, and ethanol-blended gasoline RE85 containing maximum 85 % ethanol) as non-aqueous phase liquids (NAPL) in soil was demonstrated in a laboratory-scale experiment. Ecotoxicity data was produced for the same fuels. There was no significant difference in migration of conventional and renewable diesel, but gasoline migrated 1.5 times deeper and 7–9 times faster in sand than diesel. RE85 spread horizontally wider but not as deep (p?Eisenia fetida followed by ethanol-blended gasoline (LC50 1,643 mg/kg THC) and conventional diesel (LC50 2,432 mg/kg THC), although gasoline evaporated fast from soil. For comparison, the toxicity of the water-accommodated fractions (WAF) of the fuels was tested with water flea Daphnia magna and Vibrio fischeri, also demonstrating groundwater toxicity. The WAF of conventional gasoline and RE85 showed almost similar toxicity to both the aquatic test species. EC50 values of 1:10 (by volume) WAF were 9.9 %WAF (gasoline) and 9.3 %WAF (RE85) to D. magna and 9.3 %WAF (gasoline) and 12.3 %WAF (RE85) to V. fischeri. Low solubility decreased toxicity potential of conventional diesel in aquatic environment, but direct physical effects of oil phase pose a threat to organisms in nature. Renewable diesel NExBTL did not show clear toxicity to any test species.