Environment-health link in a context of urban agricultures: studies of oral exposure to pollutants in order promote the human health

Environmental Science and Pollution Research -     

Activated carbon produced from waste coffee grounds for an effective removal of bisphenol-A in aqueous medium

Environmental Science and Pollution Research - Bisphenol-A is widely used chemical in industry and unfortunately often detected in natural waters. Considered as an emerging pollutant, bisphenol-A...     

Concentrations of cadmium and other metals in Fucus vesiculosus L. and Fontinalis dalecarlica Br. Eur. from the northern Baltic Sea and the southern Bothnian Sea

Concentrations of Cd and ten other metals (Al, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) were determined in the brown seaweed Fucus vesiculosus L. and the aquatic moss, Fontinalis dalecarlica Br. Eur. from the northern Baltic Sea and the southern Bothnian Sea. Elevated concentrations of metals were found in samples taken close to densely populated areas, such as Stockholm and Nyn?shamn. Very high concentrations of especially Zn were found in both Fucus and Fontinalis samples taken from the area south of the Gulf of G?vle. The results indicate that mining and industrial activities along the river Dal?lven are the main sources of Zn and several other metals. Cd concentrations in Fucus plants reached maximum values (24.5 mg kg(-1)) at the northern site. The gradual increase of Cd concentrations in Fucus plants northward could not be totally explained by the salinity gradient in the Baltic Sea; reasons for this are discussed in this paper.     

Stage dependent susceptibility to lead in Bufo arenarum embryos

The stage dependent susceptibility to lead in amphibian development was studied by exposing Bufo arenarum embryos during neurulae, neuromuscular activity and gill circulation stages for twenty hours to 1 ppm Pb(2+). Survival, malformations and behavioral disorders were evaluated. The embryonic susceptibility to lead was markedly stage dependent. The survival at the neuromuscular activity stage was approximately half that of the other two periods; concerning malformations, the gill circulation stage was the least sensitive. The observed malformations consisted of failed closure of neural tube, hydropsy, small and cylindrical tails, reduced body size and incurvations in the body axis. Some alterations occurred in all experimental groups and therefore were considered non-dependent on the period of treatment. In all experimental embryos, neurological disorders such as trembles and loss of equilibrium were observed.     

Natural phillipsite as a matrix for a slow-release formulation of oxamyl

The performance of phillipsite as a matrix for slow-release formulation of oxamyl [N,N-dimethyl-2-methylcarbamoyl-oxymino-2-(methylthio)acetamide] was tested. The adsorption kinetics followed a first-order law, and the adsorption isotherm fitted well in a two-surface Langmuir model, suggesting a double mechanism of interaction between oxamyl and the sorbent. The sorption mechanism, studied by FTIR, provided two fractions of oxamyl. The first one is sorbed on the mineral surface, linked by H-bonding, and the second one is constituted by a multilayer of oxamyl molecules linked by a water bridge between them. The release kinetics of oxamyl from a substratum zeolite-oxamyl also follows a first-order law, with two stages that correspond to both fractions of oxamyl previously detected.     

Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St Lawrence River estuary--I. Concentrations and patterns of specific PCBs, chlorinated pesticides and polychlorinated dibenzo-p-dioxins and dibenzofurans

Blubber samples from beluga whales (Delphinapterus leucas) in the St Lawrence River estuary were analysed for PCB congeners (ortho- and non-ortho-substituted) and other persistent organochlorines as well as chlorinated dibenzo-dioxins/furans (PCDD/Fs). Major individual components (mean concentrations > 1 microg g(-1)) were 4,4'-DDE, -DDD and -DDT, T12 (a toxaphene-related compound), trans-nonachlor, oxychlordane, mirex, HCB, tris(p-chlorophenyl) methane and dieldrin. Concentrations of SigmaPCBs (8.3-412 microg g(-1)), SigmaDDT (3.36-389 microg g(-1)) and mirex (0.18-6.8 microg g(-1)) were particularly elevated relative to other odontocetes in Canadian waters. SigmaDDT, PCBs (as Aroclor), mirex and T12 concentrations were positively correlated with age of adult females (> 10 years) but only weakly, or not significantly, correlated with age of adult males. PCDD/Fs were present at low ng kg(-1) levels and consisted mainly of penta- and hexachlorofurans, and hepta- and octachlorodioxin. CB126 (3,3',4,4',5-PCB) was the most prominent non-ortho-substituted PCB congener in beluga blubber. Total TCDD toxic equivalents averaged 330 ng kg(-1) in females and 1400 ng kg(-1) in males and were dominated by CB126, and the mono-ortho-substituted congeners CB105 and CB118. Biomagnification factors (BMFs) for mirex and SigmaPCB from fish to beluga ranged from 11 to 16, and were similar to BMFs in Arctic animals, indicating that elevated levels in St Lawrence animals are a consequence of relatively high levels of recalcitrant organochlorines in prey of the beluga in the St Lawrence river system.     

Effects of the phenylurea herbicide isoproturon on periphytic diatom communities in freshwater indoor microcosms

The toxic effects of the phenylurea herbicide Isoproturon -IPU: (3-(4-isopropylphenyl)-1, 1-dimethylurea)-were studied on the colonization of periphytic diatom communities, within indoor microcosms consisting of a mixed biotope (water column and natural sediment) and two biological species-rooted macrophyte cuttings (Elodea densa) and benthic bivalve molluscs (Corbicula fluminea). The periphyton, essentially composed of diatoms, was collected on artificial substrata (glass slides) in the upper layers of the water column, after two periods of exposure (34 and 71 days). IPU was initially added in the water or in the sediment compartment, at two nominal concentrations (L1 and L2 levels) for each contamination source-5 and 20 microg litre(-1) and 100 and 400 microg kg(-1) in sediment (w/w) respectively. The effects of IPU on the density and community structure of periphytic diatoms are described. A marked reduction in the diatom density was observed after 34 days exposure to the lower concentration of IPU in the water (5 microg litre(-1)). For the L2 levels, the very small number of live cells present did not permit quantification of the diatom density. After 71 days, recovery in community parameters occurred for the two contamination levels of the sediment and water column sources. Samples collected in the experimental units contaminated with the L2 levels were dominated by heterotrophic and smaller diatom species, such as Sellaphora seminulum. Data treatment based on factorial discriminant analysis enabled us to distinguish the different contamination conditions, with only 11 species from the 130 taxa identified.     

Analysis of gaseous diisocyanates in air using chemosorption sampling

A sampling procedure for 2,4- and 2,6-toluenediisocyanate (TDI) and 4,4′-diphenylmethane diisocyanate (MDI) in the range 0.007-0.7 mg/m³ in a 15 L air sample is described. The sampling is performed with 9-(N-methylaminomethyl)-anthracene (MAMA) adsorbed on a solid sorbent, Amberlite XAD-2. The recoveries are 80–100% in this chemosorption reaction. The urea derivatives are desorbed with N,N-dimethylformamide and analysed by high performance liquid chromatography (HPLC). Samples and prepared chemosorption tubes are stable for at least two weeks if stored in the dark. To complete the investigation, field measurements of TDI were performed in an industrial atmosphere.     

Surfactant solubilization of hydrophobic compounds in soil and water

The soil/water partition coefficient (K_d) of hexachlorobenzene (HCB) ranged from 220 1/kg to 1800 1/kg for eight soils having a wide range of physico-chemical properties. K_d normalised to soil organic carbon (K_oc) was found to be 28000 ± 4800 1/kg. Anionic surfactant dodecylsulphate (DS) present at concentrations above the critical micellar concentration (CMC) caused reductions in the apparent soil/water partition coefficient (K_d ^*) in the range of 3–26 times for most soils and up to 36–91 times for sandy soils. Below CMC, at environmentally relevant surfactant concentrations, K_d ^* was reduced by a factor of 1–13. For clay and calcareous soils significant adsorption/complexation/precipitation of DS occurred. At the lowest DS concentration this produced a two-fold increase in K_d ^*. At increasing DS concentrations this effect was shielded by the solubihzing effect from DS. Monomer (K_mn) and micellar (K_mc) surfactant/water partition coefficients for HCB were determined to be, 980 ± 190 1/kg and 21000 ± 1600 1/kg, respectively.     

Geochemical and Pb isotopic evidence for sources and dispersal of metal contamination in stream sediments from the mining and smelting district of Príbram, Czech Republic

Stream sediments from the mining and smelting district of Príbram, Czech Republic, were studied to determine the degree, sources and dispersal of metal contamination using a combination of bulk metal and mineralogical determinations, sequential extractions and Pb isotopic analyses. The highest metal concentrations were found 3-4 km downstream from the main polymetallic mining site (9800 mg Pb kg(-1), 26 039 mg Zn kg(-1), 316.4 mg Cd kg(-1), 256.9 mg Cu kg(-1)). The calculated enrichment factors (EFs) confirmed the extreme degree of contamination by Pb, Zn and Cd (EF>40). Lead, Zn and Cd are bound mainly to Fe oxides and hydroxides. In the most contaminated samples Pb is also present as Pb carbonates and litharge (PbO). Lead isotopic analysis indicates that the predominant source of stream sediment contamination is historic Pb-Ag mining and primary Pb smelting (206Pb/207Pb=1.16), while the role of secondary smelting (car battery processing) is negligible.