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Environmental exposure to organochlorine pesticides and deficits in cochlear status in children 全文
2015
Sisto, Renata | Moleti, Arturo | Palkovičová Murínová, Ľubica | Wimmerová, Soňa | Lancz, Kinga | Tihányi, Juraj | Čonka, Kamil | Šovčíková, Eva | Hertz-Picciotto, Irva | Jusko, Todd A. | Trnovec, Tomáš
The aim of this study was to examine the hypothesis that organochlorine pesticides (OCPs), hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), and 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p′-DDT) and its metabolite 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p′- DDE) are ototoxic to humans. A multivariate general linear model was designed, in which the statistical relation between blood serum concentrations of HCB, β-HCH, p,p′-DDT, or p,p′-DDE at different ages (at birth, 6, 16, and 45 months) and the distortion product otoacoustic emissions (DPOAEs) was treated as multivariate outcome variables. Polychlorinated biphenyl (PCB) congeners and OCPs were strongly correlated in serum of children from our cohort. To ascertain that the association between DPOAEs at a given frequency and concentration of a pesticide is not influenced by PCBs or other OCP also present in serum, we calculated benchmark concentrations (BMCs) relating DPOAEs to a serum pesticide alone and in presence of confounding PCB-153 or other OCPs. We found that BMCs relating DPOAEs to serum pesticides are not affected by confounders. DPOAE amplitudes were associated with serum OCPs at all investigated time intervals, however, in a positive way with prenatal exposure and in a negative way with all postnatal exposures. We observed tonotopicity in the association of pesticides with amplitude of DPOAEs as its strength was frequency dependent. We conclude that exposure to OCPs in infancy at environmental concentrations may be associated with hearing deficits.
显示更多 [+] 显示较少 [-]Air pollution by allergenic spores of the genus Alternaria in the air of central and eastern Europe 全文
2015
Kasprzyk, Idalia | Rodinkova, Victoria | Šaulienė, Ingrida | Ritenberga, Olga | Grinn-Gofron, Agnieszka | Nowak, Małgorzata | Sulborska, Aneta | Kaczmarek, Joanna | Weryszko-Chmielewska, Elzbieta | Bilous, Elena | Jedryczka, Malgorzata
Spores of the genus Alternaria belong to one of the most prevailing constituents of the air in all regions of the world. They form infectious inoculum of numerous plant species as well as severe inhaled allergies. The aim of this study was to compare the biological pollution with Alternaria spores of the air of 12 cities located in central and eastern Europe. The experiment was done in 2010 and it covered the territory of Latvia (LV), Lithuania (LT), Poland (PL) and Ukraine (UA). The spores were counted using an identical method and standard equipment (7-day Lanzoni volumetric sampler) followed by extensive statistical calculations. The timing of the day of maximum concentration changed mainly along the N-S direction and had a positive correlation with latitude. The most important factor determining the increase in Alternaria spore concentration was the temperature, whereas other weather parameters were not related or of low significance. Regardless of geographical location, the first phase of the season (0–0.9 % of Alternaria spores in the air) was the longest (up to 60 days) and the last (97.5 to 99 %) was the shortest (22 days or less). The means of daily concentrations of Alternaria spores ranged from 11 spores m⁻³ in Klaipeda (LT, Baltic Sea coast) to 187 in Poznan (west PL, agricultural plain). The threshold value of 80 spores m⁻³ that triggers the first allergy symptoms was exceeded in 8 to 86 days (Vinnitsa, UA, temperate continental, forest-steppes region). There were considerable differences between the highest number of spores per cubic metre of air, varying from 139 in the north (Klaipeda, LT) to 2,295 in central west (Poznan, PL). The biological pollution by Alternaria spores in several places of central and eastern Europe was high; the number of days exceeding the threshold value of 300 spores m⁻³ connected with serious health problems of atopic people ranged from 0 to 1 on the north (LV, LT) to 29 in central west (Poznan, PL).
显示更多 [+] 显示较少 [-]Occurrence and fate of acrylamide in water-recycling systems and sludge in aggregate industries 全文
2015
Junqua, Guillaume | Spinelli, Sylvie | Gonzalez, Catherine
Acrylamide is a hazardous substance having irritant and toxic properties as well as carcinogen, mutagen, and impaired fertility possible effects. Acrylamide might be found in the environment as a consequence of the use of polyacrylamides (PAMs) widely added as a flocculant for water treatment. Acrylamide is a monomer used to produce polyacrylamide (PAM) polymers. This reaction of polymerization can be incomplete, and acrylamide molecules can be present as traces in the commercial polymer. Thus, the use of PAMs may generate a release of acrylamide in the environment. In aggregate industries, PAM is widely involved in recycling process and water reuse (aggregate washing). Indeed, these industries consume large quantities of water. Thus, European and French regulations have favored loops of recycling of water in order to reduce water withdrawals. The main goal of this article is to study the occurrence and fate of acrylamide in water-recycling process as well as in the sludge produced by the flocculation treatment process in aggregate production plants. Moreover, to strengthen the relevance of this article, the objective is also to demonstrate if the recycling system leads to an accumulation effect in waters and sludge and if free acrylamide could be released by sludge during their storage. To reach this objective, water sampled at different steps of recycling water process has been analyzed as well as different sludge corresponding to various storage times. The obtained results reveal no accumulation effect in the water of the water-recycling system nor in the sludge.
显示更多 [+] 显示较少 [-]Temporal dynamics of the cellular events in tobacco leaves exposed in São Paulo, Brazil, indicate oxidative stress by ozone 全文
2015
Pedroso, Andrea Nunes Vaz | Alves, Edenise Segala
Nicotiana tabacum ‘Bel-W3’ is widely used as an ozone bioindicator species, showing typical necrosis preceded by microscopic markers of oxidative stress. This study aimed to follow the development of symptoms in tobacco exposed in São Paulo highlighting the temporal dynamics of the cellular events. Leaves with and without necrosis were processed according to standard techniques for anatomical analyses. Leaves from the site with higher SUM00 presented thinner palisade parenchyma, fewer layers of spongy parenchyma, higher stomatal density, clusters of vessel elements in the midrib, erosion of cuticular waxes and stomatal damage. The sequence of microscopic events from the third day of exposure were condensation of the cytoplasm in parenchyma tissue, sinuosity of anticlinal walls, pectinaceous cell wall protrusions, chromatin condensation and changes in chlorophyll autofluorescence. On the 14th day of exposure, these events finally led to cell death in the palisade parenchyma and necrosis on the leaf. The markers observed indicated oxidative stress caused by ozone.
显示更多 [+] 显示较少 [-]Spatial distribution and health risk assessment of toxic metals associated with receptor population density in street dust: a case study of Xiandao District, Changsha, Middle China 全文
2015
Li, Fei | Huang, Jinhui | Zeng, Guangming | Huang, Xiaolong | Liu, Wenchu | Wu, Haipeng | Yuan, Yujie | He, Xiaoxiao | Lai, Mingyong
Spatial characteristics of the properties (dust organic material and pH), concentrations, and enrichment levels of toxic metals (Ni, Hg, Mn and As) in street dust from Xiandao District (Middle China) were investigated. Method of incorporating receptor population density into noncarcinogenic health risk assessment based on local land use map and geostatistics was developed to identify their priority pollutants/regions of concern. Mean enrichment factors of studied metals decreased in the order of Hg ≈ As > Mn > Ni. For noncarcinogenic effects, the exposure pathway which resulted in the highest levels of exposure risk for children and adults was ingestion except Hg (inhalation of vapors), followed by dermal contact and inhalation. Hazard indexes (HIs) for As, Hg, Mn, and Ni to children and adults revealed the following order: As > Hg > Mn > Ni. Mean HI for As exceeded safe level (1) for children, and the maximum HI (0.99) for Hg was most approached the safe level. Priority regions of concern were indentified in A region at each residential population density and the areas of B at high and moderate residential population density for As and the high residential density area within A region for Hg, respectively. The developed method was proved useful due to its improvement on previous study for making the priority areas of environmental management spatially hierarchical and thus reducing the probability of excessive environmental management.
显示更多 [+] 显示较少 [-]Occurrence and behaviors of fluorescence EEM-PARAFAC components in drinking water and wastewater treatment systems and their applications: a review 全文
2015
Yang, Liyang | Hur, Jin | Zhuang, Wane
Fluorescence excitation emission matrices-parallel factor analysis (EEM-PARAFAC) is a powerful tool for characterizing dissolved organic matter (DOM), and it is applied in a rapidly growing number of studies on drinking water and wastewater treatments. This paper presents an overview of recent findings about the occurrence and behavior of PARAFAC components in drinking water and wastewater treatments, as well as their feasibility for assessing the treatment performance and water quality including disinfection by-product formation potentials (DBPs FPs). A variety of humic-like, protein-like, and unique (e.g., pyrene-like) fluorescent components have been identified, providing valuable insights into the chemical composition of DOM and the effects of various treatment processes in engineered systems. Coagulation/flocculation-clarification preferentially removes humic-like components, and additional treatments such as biological activated carbon filtration, anion exchange, and UV irradiation can further remove DOM from drinking water. In contrast, biological treatments are more effective for protein-like components in wastewater treatments. PARAFAC components have been proven to be valuable as surrogates for conventional water quality parameter, to track the changes of organic matter quantity and quality in drinking water and wastewater treatments. They are also feasible for assessing formations of trihalomethanes and other DBPs and evaluating treatment system performance. Further studies of EEM-PARAFAC for assessing the effects of the raw water quality and variable treatment conditions on the removal of DOM, and the formation potentials of various emerging DBPs, are essential for optimizing the treatment processes to ensure treated water quality.
显示更多 [+] 显示较少 [-]Effects of fluoranthene on the fitness-related traits and antioxidative defense in Lymantria dispar L 全文
2015
Mrdaković, Marija | Ilijin, Larisa | Vlahović, Milena | Todorović, Dajana | Gavrilović, Anja | Mrkonja, Aleksandra | Perić-Mataruga, Vesna
This study aimed to examine the effects of ubiquitous polycyclic aromatic hydrocarbon fluoranthene, supplemented to an artificial diet, on the fitness-related traits and activity of midgut antioxidative enzymes—superoxide dismutase (SOD) and catalase (CAT), and expression of their isoforms in the fifth-instar gypsy moth Lymantria dispar L. Prolonged duration of development and reduced weight and relative growth rate were recorded in larvae reared on the diets supplemented with different concentrations of fluoranthene. SOD and CAT activities were significantly higher in the midguts of fluoranthene-treated larvae, compared to that of the control group. Different expression patterns were detected for SOD as well as for CAT isoforms, depending on the supplemented concentration of fluoranthene. Obtained results suggest that the activity of these enzymes in gypsy moth larvae may be used as biomarkers for assessing pollution, even at low concentrations of the pollutant.
显示更多 [+] 显示较少 [-]Combining chemical and biological endpoints, a major challenge for twenty-first century’s environmental specimen banks 全文
2015
Garmendia, Larraitz | Izagirre, Urtzi | Soto, Manu | Lermen, Dominik | Koschorreck, Jan
Environmental specimen banks (ESBs) are not a new phenomenon, but in the last decades, the steep rate in the establishment of new ESBs is a sign to address new research approaches for scientists. In this way, environmental biobanking is becoming a well-organized and effective vehicle to collect samples of high quality making them available for future researchers. The endpoints promoted in the ESBs are mainly based on chemical approaches, but the necessity to add biological endpoint is fundamental (e.g., assessment of the environmental health status). Moreover, advances and development of high sensitive, high-throughput techniques along with ecotoxicological approaches based on biomarkers are stimulating a new demand for stored specimens and associated data. Like in chemically targeted environmental specimen banking, the banked samples for the assessment of biological effects also require guidance informed by knowledge of their practices and challenges, along with policies for the correct advancement of research goals and appropriate and effective biobank governance.
显示更多 [+] 显示较少 [-]Organochlorines in free-range hen and duck eggs from Shanghai: occurrence and risk assessment 全文
2015
Xu, Meng | Qiu, Yanling | Bignert, Anders | Zhou, Yihui | Zhu, Zhiliang | Zhao, Jianfu
As an important part of the residents’ diet in China, the consumption of hen and duck eggs has been increasing rapidly in the past decades. Being rich in protein and lipid, eggs may be one of the main exposure routes for persistent organic pollutants (POPs) to human beings. In this study, four kinds of free-range hen and duck eggs were collected from two traditional egg-producing areas in Shanghai, namely Dianshan Lake Area and Jinshan Industry Zone. Organochlorine pesticides (OCPs, 18 compounds) and polychlorinated biphenyls (PCBs, 14 compounds) were analyzed with 41 egg samples. Among all OCPs, dichlorodiphenyltrichloroethanes (DDTs) were the dominant contaminant, with the concentrations ranging from 100 to 730 ng/g, lw. Unlike the 4,4′-DDE as the predominant DDTs congener in other three kinds of eggs, the duck eggs from Jinshan Industrial Zone had an abnormally high concentration of 2,4′-DDD, which may be related to ducks’ feedings in the water. The levels of hexachlorocyclohexanes (HCHs) and pentachloroanisole (PCA) in eggs from different places were similar to each other, while hexchlorobenzene (HCB) for hen eggs from Dianshan Lake was much higher than other eggs. According to the results, the DDTs residues detected in this study were mainly due to the historical usage, whereas the high ratio of γ-HCH/α-HCH suggested that there might be some recent input of lindane in these two areas. For PCBs, the congener profiles varied among species. Low molecular PCBs (Tri-PCBs and Tetra-PCBs) were main congeners for duck eggs from Dianshan Lake and all hen eggs, while high molecular PCBs accounted for more than 50 % for duck eggs from Jinshan Industrial Zone, which was consistent with the water analysis results of the synchronous study from our group. This study suggests that Dianshan Lake Area may not be a good reference area for POPs monitoring in Shanghai. The estimated daily intakes of DDTs, HCHs, HCBs, and PCBs were far below the reference limits, showing no significant health risk for human consumption by eating eggs collected in this study.
显示更多 [+] 显示较少 [-]Fate of phthalates and BPA in agricultural and non-agricultural soils of the Paris area (France) 全文
2015
Tran, Bich Chau | Teil, Marie-Jeanne | Blanchard, Martine | Alliot, Fabrice | Chevreuil, Marc
This study (i) investigated the concentration levels of nine phthalates and bisphenol A (BPA) in sludge samples originating from a French wastewater treatment plant (WWTP), (ii) studied the distribution of target compounds according to soil depth and calculated their half-lives, and (iii) compared the contamination level of the agricultural soil with those of soils with other land uses. The sludge contamination levels varied from a few hundred nanograms per gram dry weight (dw) for diethyl phthalate (DEP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and butyl-benzyl phthalate (BBP) to a few micrograms per gram dw for diethylhexyl phthalate (DEHP), di-iso-nonyl phthalate (DiNP), and di-iso-decyl phthalate (DiDP). After sludge application, an 8-fold increase for DEHP level and a 3-fold increase for BPA level occurred in the surface horizon of the soil. The mean distribution of phthalates according to the depth showed a positive gradient for the low molecular weight compounds and inversely, a negative gradient for the highest ones. The half-lives in the 0–20-cm soil horizon were 64 days for DEHP and 36 days for BPA. A predictive environmental concentration (PEC) of 0.3 μg g⁻¹ dw was estimated for DEHP, while the experimental value was 0.16 μg g⁻¹ dw, suggesting degradation processes in soil and/or formation of non-extractable residues. Comparisons of contamination levels for soils from different origins (urban, rural, agricultural, and forest) showed that the urban soil remained the most contaminated one, prior to the agricultural soil after treatment.
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