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The importance of ingested soils in supplying fluorine and lead to sheep grazing contaminated pastures in the Peak District mining area of Derbyshire, UK
2013
Abrahams, Peter W. | Blackwell, Nia L.
For sheep grazing pastures in areas of mineralisation and former metalliferous mining activity, an excessive intake of potentially harmful elements (PHEs) such as fluorine (F) and lead (Pb) can result in clinical and subclinical toxicity. The prime aim of our work was to calculate the intakes of both of these PHEs by sheep grazing pastures in the mineralised/mined Peak District area of Derbyshire. The bi-monthly sampling of topsoils (0-15 cm depth) and the faeces of sheep from fields at seven farms was undertaken for a 1-year period. These samples were analysed for titanium that allowed the rates of soil ingestion (and hence also herbage ingestion since we assume that the sheep have an overall diet of 1 kg dry matter (DM)/day) to be determined. Our findings were then combined with previously published soil and soil-free pasture herbage F and Pb concentrations determined from the seven farms to calculate the intakes of both PHEs. The results show seasonal variations of soil ingestion at the seven farms ranging from <0.1 to 20.1 % of the DM intake (median = 3 %), with the highest rates of ingestion being associated with the winter-spring (i.e. December-April) period. Our calculations show that at some farms, sheep can be exposed to dietary concentrations in excess of recommended guidelines potentially throughout the whole year, though livestock movement to less-contaminated pastures would lessen any toxic impact. Because the soil concentrations are greater than those associated with soil-free pasture herbage, ingested soils are the main dietary source of Pb and (especially) F to sheep. However, subjecting freshly sampled topsoils to sequential extraction procedures undertaken in the laboratory indicates that the majority of Pb and (especially) F may not be readily soluble in the ovine digestion system, so reducing the quantities of both PHEs available for absorption.
Show more [+] Less [-]Trace metals in flounder, Platichthys flesus (Linnaeus, 1758), and sediments from the Baltic Sea and the Portuguese Atlantic coast
2013
Polak-Juszczak, Lucyna
Trace metals were examined in the muscle tissue of flatfish species of flounder, Platichthys flesus (Linnaeus, 1758), sediments from two southern Baltic Sea sites (Gdańsk Bay and Ustecko-Łebskie as a reference) and in two areas of the Portuguese Atlantic coast (Douro River estuary and Atlantic fishing ground as a reference) to evaluate spatial differences in trace metals. Additionally, the accumulation of trace metals in flounder of different length classes was assessed. Flounder from the Gdańsk Bay area contained twofold more cupper (Cu), lead (Pb) and mercury (Hg) than did flounder from the Douro River estuary, but zinc (Zn) and cadmium (Cd) were at similar concentrations. The sediments from Gdańsk Bay contained significantly more Zn and threefold more Cd, while concentrations of Cu and Pb were twofold lower. The concentrations of metals in the sediments did not correlate with those in the flounder. Spatial differences were noted in metal concentrations in flounder from the southern Baltic Sea and the Portuguese Atlantic coast as well as within these regions, with higher concentrations in the flounder from the Baltic Sea Gdańsk Bay. The flounder in length class 25-30 cm from Gdańsk Bay contained metal concentrations comparable to those of class 40-45 cm specimens from the Atlantic coast. The accumulation of metals in flounder length classes differed in the two regions.
Show more [+] Less [-]Meta-analysis of environmental contamination by phthalates
2013
Bergé, Alexandre | Cladière, Mathieu | Gasperi, Johnny | Coursimault, Annie | Tassin, Bruno | Moilleron, Régis
Phthalate acid esters (PAE), commonly named phthalates, are toxics classified as endocrine-disrupting compounds; they are primarily used as additives to improve the flexibility in polyvinyl chloride. Many studies have reported the occurrence of phthalates in different environmental matrices; however, none of these studies has yet established a complete overview for those compounds in the water cycle within an urban environment. This review summarizes PAE concentrations for all environmental media throughout the water cycle, from atmosphere to receiving waters. Once the occurrences of compounds have been evaluated for each environmental compartment (urban wastewater, wastewater treatment plants, atmosphere, and the natural environment), we reviewed data in order to identify the fate of PAE in the environment and establish whether geographical and historical trends exist. Indeed, geographical and historical trends appear between Europe and other countries such as USA/Canada and China, however they remain location dependent. This study aimed at identifying both the correlations existing between environmental compartments and the processes influencing the fate and transport of these contaminants into the environment. In Europe, the concentrations measured in waterways today represent the background level of contamination, which provides evidence of a past diffuse pollution. In contrast, an increasing trend has actually been observed for developing countries, especially for China.
Show more [+] Less [-]Perfluorinated compounds and organochlorine pesticides in soils around Huaihe River: a heavily contaminated watershed in Central China
2013
Meng, Jing | Wang, Tieyu | Wang, Pei | Giesy, John P. | Lü, Yonglong
Perfluorinated compounds (PFCs) and organochlorine pesticides (OCPs) were analyzed in surface soils along the Huaihe River. Sixteen target PFCs and nine OCPs were quantified in soils from a region of intensive industrial and agricultural development. Concentrations of PFCs and OCPs ranged from less than the limit of detection (LOD) to 1.22 ng/g and 3.63 to 227 ng/g, respectively. Contamination by OCPs was more serious than that of PFCs, which was consistent with the fact that OCPs were widely used in agriculture of the district while there was no known production or application of PFCs in the study area. The predominant PFCs in soils were PFOA and PFOS with concentrations that ranged from <LOD to 0.20 ng/g and <LOD to 0.21 ng/g, respectively. Among the three groups of OCPs, average concentrations of HCHs, DDTs, and HCB were 4.7, 23.7, and 1.4 ng/g, respectively. Results of principal component analysis revealed relatively weak associations between concentrations of PFCs and those of OCPs, while concentrations of OCPs exhibited similar patterns of distributions. Among the mainstream and five tributaries, the highest concentrations of PFCs were observed along the Pihe River, while the highest concentrations of OCPs occurred along the Xifeihe River. In general, concentrations of PFCs were evenly distributed, while those of OCPs exhibited relatively greater spatial differences.
Show more [+] Less [-]The assessment of particulate matter emitted from stone-crushing industry by correlating rock textures with particles generated after comminution and dispersed in air environment
2013
Belardi, Girolamo | Vignaroli, Gianluca | Plescia, Paolo | Passeri, Luciano
The generation and emission of particulate matter from abrasion industry are subjects of the pollution monitoring by multidisciplinary study involving earth sciences and engineering disciplines. This work investigates the correlation between textural properties of in situ rock with class size distribution and morphology of particles generated after rock comminution and particles emitted in the air. A special comminution-dust sampling architecture was realised. The combined use of scanning electron microscopy and particle size analyser was considered in performing digital image analysis on both crushed products and airborne particles collected onto membrane filters. The results show that the size and morphology of crushed particles are linked to the petrographic rock properties. In particular, particles with fibrous morphology are prominent in rocks showing foliated textures where elongated minerals occurred, with implication for asbestos-bearing rocks. For what concerns the airborne particles, the results show that their aerodynamic diameters are independent of the crusher operating conditions. External parameters probably intervene in the distribution of the airborne particles emission, including the dynamic air fluxes, or environmental conditions. By applying mathematical models, the morphology and size range of airborne particles following the comminution processes can be predicted, and results has implication for pollutants contamination due to particulate matters emitted by crush stone industry.
Show more [+] Less [-]Effects of copper fungicide residues on the microbial function of vineyard soils
2013
Wightwick, Adam M. | Salzman, Scott A. | Reichman, Suzanne M. | Allinson, Graeme | Menzies, Neal W.
The use of copper-based fungicides leads to an accumulation of copper (Cu) in vineyard soils, potentially causing adverse effects to the microbial function and fertility of the soil. This study used a soil microcosm approach to assess the effects of Cu accumulation on microbial function in vineyard soils. Surface soil samples were collected from 10 vineyards and a number of un-impacted reference sites in each of three different viticultural regions of Australia. The field-collected soils were transferred to microcosms and maintained for up to 93 days in the laboratory at 20–22 °C and 60 % of their maximum water-holding capacity. The microbial function of the soils was indicated by measuring phosphomonoesterase, arylsulfatase, urease, and phenol oxidase activities. In general, the vineyard soils had greater concentrations of Cu and lower enzyme activities than in the reference soils, although a weak negative relationship between Cu and enzyme activity could only be found for phosphomonoesterase activity. The results show that soil physical–chemical properties (i.e., organic carbon, pH) are greater determinants of soil enzyme activity than increased soil Cu concentration at the Cu concentrations present in vineyard soils.
Show more [+] Less [-]Semen quality of environmentally exposed human population: the toxicological consequence
2013
Pant, Niraj | Pant, A. B. | Chaturvedi, P. K. | Shukla, M. | Mathur, N. | Gupta, Y. K. | Saxena, D. K.
Human data on the relationship of semen quality with pesticide and metals are mostly inconsistent. The purpose of the study is to confirm the toxicity of organochlorine pesticide β- and γ-hexachlorocyclohexane (HCH), DDE and DDD, and metals lead or cadmium on sperm motility in epidemiological study among fertile and infertile men and to determine whether in vivo and in vitro results are in the same direction. Semen analysis and estimation of the toxicants were done in 60 fertile and 150 infertile men. In the in vitro studies, sperm were exposed to the highest levels of these toxicants found in vivo, as well as five and ten times higher, and to the mixture of all compounds. The study assesses sperm viability and motility for a period ranging between 30 min and 96 h. Epidemiological data showed an inverse correlation of toxicant with sperm motility. In vitro study showed that γ-HCH and lead after 12 h, cadmium after 8 h, and coexposure to toxicants after 6 h of exposure caused significant concentration- and duration-dependent decline in sperm motility. Data of in vitro study were concurrent with epidemiological finding that might be useful in establishing the possible association between exposure and effect of these selected pollutants on sperm motility.
Show more [+] Less [-]Multiple biomarkers of pollution effects in Solea solea fish on the Tunisia coastline
2013
Jebali, Jamel | Sabbagh, Marwa | Banni, Mohamed | Kamel, Naouel | Ben-Khedher, Sana | M’hamdi, Naceur | Boussetta, Hamadi
This field study investigates the morphological indices (condition index, hepatosomatic index) and biochemical (catalase (CAT), glutathione S-transferase (GST), acetylcholinesterase (AChE), metallothionein (MT), lipid peroxidation) parameters in liver, gills and kidney of common sole (Solea solea) originating from different sites of the Tunisian coast area impacted by different anthropogenic activities. Differences among sites and tissues for AChE, GST, CAT, MT and TBARS were found and possibly related to known sources of domestic and industrial discharges in the studied sites. Liver, gills and kidney CAT, liver and kidney MT and brain AChE were key biomarkers to discriminate fish of different sites. So, we suggest using these biomarkers in future biomonitoring.
Show more [+] Less [-]Can conservation of single surrogate species protect co-occurring species?
2013
Kang, Dongwei | Yang, Hongwei | Li, Junqing | Chen, Youping
Conservation of surrogate species is expected to benefit co-occurring species with similar distributions that share the same habitat, yet the usefulness of this approach to protect nontarget species has been extensively challenged. In this study, we aimed to assess whether co-occurring species could be afforded protection under the conservation of two proposed surrogate species, the giant panda and the takin. We undertook a thorough study on the habitat requirements of these two endangered species, based on the analysis of their habitat preferences. The results revealed that the giant panda exhibits more specialized habitat preferences than does the takin and that habitat separation between these species mainly reflected differences in their dietary requirements and preferences. We suggest that these differences might facilitate their coexistence in sympatric areas. Meanwhile, results of a discriminant function analysis showed that protection of giant pandas would protect 82.1 % of the panda's habitat, but only 25.4 % of the takin's habitat and just 57.0 % of the joint habitats of these species. Importantly, our results also showed that a joint surrogate species approach to conservation would protect 86.9 % of the panda's habitat, 53.7 % of the takin's habitat, and 72.2 % of the joint habitats of these species. This is a higher degree of habitat protection than the single surrogate conservation of pandas. We conclude that the joint surrogate species approach should be adopted to improve biodiversity conservation.
Show more [+] Less [-]Ambient air quality and asthma cases in Niğde, Turkey
2013
Kara, Ertan | Özdilek, Hasan Göksel | Kara, Emine Erman
Urban air quality is one of the key factors affecting human health. Turkey has transformed itself into an urban society over the last 30 years. At the same time, air pollution has become a serious impairment to health in many urban areas in the country. This is due to many reasons. In this study, a nonparametric evaluation was conducted of health effects that are triggered by urban air pollution. Niğde, the city which is the administrative centre of Nigde province was chosen of the effects of air pollution since, like many central Turkish cities, it is situated on a valley where atmospheric inversion occurs. In this paper, the relationship between ambient urban air quality, namely PM₁₀ and sulphur dioxide (SO₂), and human health, specifically asthma, during the winter season is examined. Air pollution data and asthma cases from 2006 to 2010 are covered in this study. The results of our study indicate that total asthma cases reported in Nigde between 2008 and 2010 were highly dependent on ambient SO₂ concentration. More asthma cases were recorded when 30 μg m⁻³ or higher SO₂ was present in the ambient air than those recorded under cleaner ambient air conditions. Moreover, it was determined that in Nigde in 2010, asthma cases reported in males aged between 45 and 64 were closely correlated with ambient SO₂ (α = 0.05).
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