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Spatial distribution and speciation of mercury and methyl mercury in the surface water of East River (Dongjiang) tributary of Pearl River Delta, South China Full text
2012
Liu, Jinling | Feng, Xinbin | Zhu, Wei | Zhang, Xian | Yin, Runsheng
PURPOSE: The distribution and speciation of mercury in surface water of East River, Guangdong province, China were investigated. METHODS: All told 63 water samples were collected during a bi-weekly sampling campaign from July 15th to 26th, 2009. RESULTS: Total mercury (THg) concentrations in water samples ranged from 11 to 49 ng/L. Maximum levels of THg were measured in the lower reaches of East River, where it passes through a major industrial area adjacent to Dongguang city. Higher ratios of dissolved mercury (THg (aq)) in proportion to THg were restricted to the downstream section of East River. Concentrations of the minor constituent methyl mercury varied in the range from 0.08 to 0.21 ng/L. On average, methyl mercury made up 0.8% and 0.56% of THg (aq) and THg, respectively. Dissolved species dominated the speciation of methyl mercury in proportions up to 81%, which may imply that methyl mercury is largely produced in situ within the river water. Environmental factors (such as water temperature, dissolved oxygen, etc.) are regarded to play an important role in Hg methylation processes were monitored and assessed. CONCLUSIONS: In an international perspective, East River must be classified as a polluted river with considerably sources within its industrial areas. The THg (aq) and particle mercury fluxes to the Pearl River Estuary by East River run-off were estimated to be 0.31 ± 0.11 and 0.17 ± 0.13 t/year, respectively. Hence, in total nearly 0.5 t Hg is annually released to the sea from the East River tributary.
Show more [+] Less [-]Occupational exposure to formaldehyde in an institute of morphology in Brazil: a comparison of area and personal sampling Full text
2012
de M. Ochs, Soraya | de O. Grotz, Lucas | Factorine, Luciara S. | Rodrigues, Mauro R. | Netto, Annibal D Pereira
BACKGROUND, AIMS, AND SCOPE: Formaldehyde (FA) is a harmful chemical, which is classified as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer. Solutions of FA that are used to preserve cadavers in research and education morphological institutes represent a risk to occupational health of professionals and students. During the dissection of cadavers in the anatomy laboratories, FA vapors are emitted, resulting in the exposure of students and their instructors to elevated levels of FA. The World Health Organization recommends an air quality guideline value of 0.1 mg m⁻³ for exposure to FA. The limit of occupational exposure adopted by the Brazilian legislation (2.3 mg m⁻³) is markedly higher than those adopted by institutions of other countries around the world. The purpose of this study was to determine the levels of personal exposure and the area concentration of FA in the morphology department of the Federal Fluminense University, Brazil, and investigate and compare the relationship between them. METHODS: Four rooms distributed in the three floors of the Morphology Department were evaluated: the embalming laboratory, the anatomy laboratories, the corridor of the teachers’ rooms, and the entrance hall. Thirty-six samples in total were collected in the second semester of 2010 and first semester of 2011. The air sampling and FA analysis were performed according to the EPA TO-11A Protocol, using a diffusive sampling device for carbonyl compounds. Personal samples were collected from monitors using a sampling device pinned on each person’s lapel. The samples were analyzed using rapid resolution liquid chromatography with UV-DAD detection at 360 nm. RESULTS AND DISCUSSION: The concentrations of FA ranged from 0.20 and 0.18 mg m⁻³ in the corridor between the teachers’ rooms, 0.03 to 0.37 mg m⁻³ in the entrance hall, 0.22 to 2.07 mg m⁻³ in the anatomy laboratory, 2.21 to 2.52 mg m⁻³, in the embalming room. The levels found in the corridor between the teachers’ rooms and in the entrance hall were lower than in other compartments because of their large distances to the sources of FA and better ventilation. The other rooms presented higher levels of FA because of the activities carried there (embalming and dissection procedures). Even in the rooms that showed the lowest levels of FA, the values found were higher than those established by all international guideline limits, except the Brazilian legislation limit, although, the concentration level in the embalming room was even greater than the Brazilian guideline. These concentrations are 100–1,000-fold higher than those reported in an FA outdoor study. The exposure levels of monitors and students ranged from 1.89 to 4.82 mg m⁻³, indicating that current practices at the Morphology Department at the university would represent a health risk. The simultaneous monitoring of area concentrations and personal exposure showed that the characteristics of classes and of cadavers’ parts, the number of students in the room and even the activities of the monitors influence the FA concentrations. CONCLUSION: This study revealed that the concentration of FA was low in the ventilated areas of the Morphology Department, and that the personal exposure when the person was close to the cadavers during the dissection procedure was higher than the mean FA concentration. This should be considered in the risk assessment of FA during these activities without effective protection equipment. It is suggested that the Brazilian legislation of exposure to formaldehyde requires an urgent update considering international legislation.
Show more [+] Less [-]Thorough analysis of polyhalogenated compounds in ray liver samples off the coast of Rio de Janeiro, Brazil Full text
2012
Rosenfelder, Natalie | Lehnert, Katja | Kaffarnik, Stefanie | Torres, Joao P. M. | Vianna, Marcelo | Vetter, Walter
INTRODUCTION: Five liver samples of two different ray species (Gymnura altavela and Zapteryx brevirostris) off the coast of Rio de Janeiro, Brazil, were analyzed for their pollution with anthropogenic and naturally occurring organohalogen compounds. MATERIAL AND METHODS: The samples were extracted with accelerated solvent extraction, and after a clean-up procedure, organohalogen compounds were separated by a modified group separation on activated silica. Subsequent analyses were done by targeted and non-targeted gas chromatography–mass spectrometry in the electron capture negative ion mode. RESULTS AND DISCUSSION: “Classic” organohalogen compounds such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and technical 1,1,1-trichloro-2,2-di(4-chlorophenyl)ethane (DDT) were detected and quantified. PCBs generally exceeded the parts per million level and represented up to 90% of the total contamination of the ray livers. High concentrations were also detected for p,p′-DDE. Non-targeted full scan investigations lead to the detection of an abundant trichlorinated compound which was identified as a new DDT metabolite in biota. Different PBDE congeners and several halogenated natural products were quantified as well. In addition, polychlorinated terphenyls were identified and analyzed in the two species. Moreover, both ray species showed different fatty acid patterns and stable carbon isotope signatures. CONCLUSIONS: The two ray species showed high concentrations of organohalogen compounds in their liver tissue. Varied δ 13C values by up to 3.1‰ indicated that the two ray species were living in different habitats.
Show more [+] Less [-]Cellular alterations and modulation of protein expression in bitumen-challenged human osteoblast cells Full text
2012
Dhondge, Alka | Surendran, Subin | Seralathan, Muhil Vannan | Naoghare, Pravin K. | Krishnamurthi, Kannan | Devi, Sivanesan Saravana | Chakrabarti, Tapan
PURPOSE: There are many arguments on the carcinogenic potential of bitumen extract. The mechanism of bitumen-induced damage is not well understood at the molecular level. Therefore, in the present study, cell-transforming and tumor-inducing potential of bitumen extract was studied using in vitro [human osteosarcoma (HOS) cells] and in vivo [nude and severe combined immunodeficiency (SCID) mice] models. METHODS: Gas chromatography/mass spectrometry (GC/MS) analysis was carried out to find out the existence of carcinogenic compounds in the bitumen extract. Cell transformation test, anchorage independence assay, karyotyping assay, tumorigenicity assay, and 2-DE analysis were used to find out the effect of bitumen using the in vitro and in vivo models. RESULTS: GC/MS analysis showed the existence of carcinogenic compounds in the bitumen extract. HOS cells were treated with different concentrations (25, 50, and 100 μl/ml) of bitumen extract. Compared to the parental HOS cells, bitumen transformants (HOS T1 and HOS T2) showed the characteristics of anchorage independency, chromosomal anomaly, and cellular transformation. Interestingly, bitumen transformants were not able to form tumor in nude/SCID mice. Proteomic analysis revealed the existence of 19 differentially expressed proteins involved in progression of cancer, angiogenesis, cell adhesion, etc. CONCLUSIONS: Exposure of bitumen extract to HOS cells results in the cellular transformation similar to cancer cells and can modulate proteins involved in the progression of cancer. We state that the non-tumorogenic potential of bitumen transformant in nude/SCID mice can be attributed to the downregulation of galectin-1, chromodomain helicase DNA-binding protein 1-like gene, and membrane-associated guanylate kinase 2 protein.
Show more [+] Less [-]RO/NF membrane treatment of veterinary pharmaceutical wastewater: comparison of results obtained on a laboratory and a pilot scale Full text
2012
Dolar, Davor | Ignjatić Zokić, Tatjana | Košutić, Krešimir | Ašperger, Danijela | Mutavdžić Pavlović, Dragana
BACKGROUND: Emerging contaminants (ECs) are commonly derived from industrial wastewater, which is often a consequence of an inadequate treatment of the latter. Improperly pretreated pharmaceutical wastewater could cause difficulties in operations of wastewater treatment plants while incomplete elimination of ECs during the processing might result in their appearance in drinking water. METHODS: This paper deals with membrane treatment of pharmaceutical wastewater on a laboratory and a pilot scale as well as with the removal of the following veterinary pharmaceuticals (VPs) (sulfamethoxazole, trimethoprim, ciprofloxacin, dexamethasone, and febantel). RESULTS: The pretreatment of pharmaceutical wastewater by means of coagulation and microfiltration (MF) prevented the irreversible fouling of the fine porous structure of the reverse osmosis (RO) and nanofiltration (NF) membranes which were used in the final stage of wastewater processing. The percentage of the removal of the selected VPs ranges from 94% to almost 100% in the case of NF and RO membranes in both scales. The recovery percentage concerning the pilot scale amounted to 88%. Membrane cleaning was successfully carried out in both scales. CONCLUSIONS: The differences in retention between laboratory and pilot tests are due to different raw wastewater quality and different recovery and hydrodynamic of the two systems. Fouling and concentration polarization were more pronounced in laboratory setup (frame-plate module) than in pilot unit (spiral module). The proposed integrated membrane treatment (coagulation, MF, NF, and RO) can be employed for treatment of wastewater originating from pharmaceutical factory. The obtained permeate can be safely discharged to sewer system or could be reused in manufacturing process.
Show more [+] Less [-]Effect directed analysis and mixture effects of estrogenic compounds in a sediment of the river Elbe Full text
2012
Schmitt, Sebastian | Reifferscheid, Georg | Claus, Evelyn | Schlüsener, Michael | Buchinger, Sebastian
INTRODUCTION: Endocrine disrupting chemicals (EDCs) are present in the environment and can have serious effects on humans and wildlife. For the establishment of environmental quality guidelines and regulation of EDCs, a better understanding and knowledge of the occurrence and the behavior of environmental EDCs is necessary. The aim of the present study was to comprehensively identify substances that are responsible for the estrogenic effect of an environmental sediment sample taken from the river Elbe/Germany. DISCUSSION: The estrogenic effect of the organic sediment extract was determined using the yeast–estrogen–screen (YES). The sample was fractionated by liquid chromatography (LC) for effect directed analysis. The composition of estrogen-active fractions was further investigated by gas chromatography–mass spectrometry and high-resolution LC–MS analysis. The composition of the environmental sample was rebuilt with pure compounds in order to assess the partition of estrogenic activity caused by the identified compounds. The organic sediment extract showed an estrogenic potential of 1.9 ± 0.4 ng/g ethinylestradiol equivalents in the sediment. The most prominent contaminants with an estrogenic potential were 17β-estradiol, estrone, and 4-iso-nonylphenols, but other xenoestrogens like bisphenol A and stigmasterol could be found as well. A rebuild of the sample was measured in the YES in order to investigate mixture effects. About 67 % of the observed estrogenic effect in the sediment extract could be explained by a mixture which contained all identified compounds. Chlorophene (o-benzyl-p-chlorophenol)—a widely used antiseptic that was also identified in the sediment extract—has xenoestrogenic properties in the YES that are in the range of other xenoestrogens like 4-n-nonylphenol. This is the first report on chlorophene acting as a xenoestrogen.
Show more [+] Less [-]Quantification of bisphenol A, 353-nonylphenol and their chlorinated derivatives in drinking water treatment plants Full text
2012
Dupuis, Antoine | Migeot, Virginie | Cariot, Axelle | Albouy-Llaty, Marion | Legube, Bernard | Rabouan, Sylvie
Bisphenol A (BPA) and nonylphenols (NP) are of major concern to public health due to their high potential for human exposure and to their demonstrated toxicity (endocrine disruptor effect). A limited number of studies have shown that BPA and NP are present in drinking water. The chlorinated derivatives that may be formed during the chlorination step in drinking water treatment plants (DWTP) exhibit a higher level of estrogenic activity than their parent compounds. The aim of this study was to investigate BPA, 353NP, and their chlorinated derivative concentrations using an accurate and reproducible method of quantification. This method was applied to both surface and treated water samples from eight French DWTPs producing from surface water. Solid-phase extraction followed by liquid chromatography–tandem mass spectrometry was developed in order to quantify target compounds from water samples. The limits of detection ranged from 0.3 to 2.3 ng/L for BPA and chlorinated BPA and from 1.4 to 63.0 ng/L for 353NP and chlorinated 353NP. BPA and 353NP were found in most analyzed water samples, at a level ranging from 2.0 to 29.7 ng/L and from 0 to 124.9 ng/L, respectively. In most of DWTPs a decrease of BPA and 353NP was observed between surface water and treated water (36.6 to 78.9 % and 2.2 to 100.0 % for BPA and 353NP, respectively). Neither chlorinated BPA nor chlorinated 353NP was detected. Even though BPA and 353NP have been largely removed in the DWTPs studied, they have not been completely eliminated, and drinking water may consequently remain a source of human exposure.
Show more [+] Less [-]Estrogenic effects of dissolved organic matter and its impact on the activity of 17β-estradiol Full text
2012
Chen, Lei | Shen, Chaofeng | Tang, Xianjin | Chen, Chen | Chen, Yingxu
BACKGROUND AND PURPOSE: The ubiquitous dissolved organic matter (DOM) is actually not inert as we always think, and the hormone-like effects of DOM have been reported. The objective of this study was to investigate the estrogenic effects of DOM and its impact on the activity of the natural estrogen 17β-estradiol (E2). MATERIALS AND METHODS: DOM of three different sources, HA sodium salt, Suwannee River natural organic matter (NOM), and Nordic Reservoir NOM, were used. The estrogenic activity was detected by using the yeast estrogen screen (YES) assay. Estrogenic effects of DOM without and after solar irradiation were tested. Influences on the action of E2 by DOM were also investigated. RESULTS: No direct estrogenic effects of the DOM used were observed in the YES assay. However, the estrogenic activities after 24 h of irradiation increased to 0.0288, 0.0178, and 0.0195 μM of E2 equivalents for HA sodium salt, Suwannee River NOM, and Nordic Reservoir NOM, respectively. After incubation of DOM, the estrogenic activity of E2 was increased by low concentrations (8.33 and 83.3 μM) of DOM while decreased by higher concentrations (8.33 × 102 and 8.33 × 103 μM) of DOM. CONCLUSIONS: Though direct estrogenic effects of DOM were not observed, increase in the estrogenic activity of DOM after irradiation was significant. DOM shows amphoteric influence on the natural estrogen E2, which depends on the concentration of DOM used. Because of its ubiquity, DOM may be of great ecological significance, playing an important role in regulating the reproduction of aquatic organisms.
Show more [+] Less [-]Heavy metal (Cd, Cr, Cu, Hg, Pb, Zn) concentrations in seven fish species in relation to fish size and location along the Yangtze River Full text
2012
Yi, Yu-Jun | Zhang, Shang-Hong
PURPOSE: The objective of this paper is to assess the regulation of the accumulation of heavy metals in the aquatic environment and different fish species. METHODS: Water and fish samples were collected from upper to lower reaches of the Yangtze River. The heavy metal (Cd, Cr, Cu, Hg, Pb, Zn) concentrations in the muscle tissue of seven fishes were measured. Additionally, the relationships between heavy metal concentrations in fish tissue and fish size (length and weight), condition factor, water layer distribution, and trophic level were investigated. RESULTS: Metal concentrations (milligrams per kilogram wet weight) were found to be distributed differently among different fish species. The highest concentrations of Cu (1.22 mg/kg) and Zn (7.55 mg/kg) were measured in Pelteobagrus fulvidraco, the highest concentrations of Cd (0.115 mg/kg) and Hg (0.0304 mg/kg) were measured in Silurus asotus, and the highest concentrations of Pb (0.811 mg/kg) and Cr (0.239 mg/kg) were measured in Carassius auratus and Cyprinus carpio. A positive relationship was found between fish size and metal level in most cases. The variance of the relationships may be the result of differences in habitat, swimming behavior, and metabolic activity. In this study, fishes living in the lower water layer and river bottom had higher metals concentrations than in upper and middle layers. Benthic carnivorous and euryphagous fish had higher metals concentrations than phytoplankton and herbivorous fish. Generally, fish caught from the lower reach had higher metals concentrations than those from the upper reach. CONCLUSIONS: Cadmium and lead concentrations in several fishes exceeded the permissible food consumption limits, this should be considered to be an important warning signal.
Show more [+] Less [-]Differential protein profile in zebrafish (Danio rerio) brain under the joint exposure of methyl parathion and cadmium Full text
2012
Ling, Xue-Ping | Lu, Ying-Hua | Huang, He-Qing
As different chemicals, methyl parathion (MP) and cadmium (Cd) can induce neurotoxicity on the brain of aquatic ecosystems. This study aims to explore the differential expression proteins in the brain induced by their joint stress and their joint effects, which are poorly reported, and devotes finding novel biomarkers for monitoring their contamination in water and assessing their neurological effects. The bioaccumulation of MP and Cd in tissues after 96 h of exposure was first analyzed by GC and inductively coupled plasma–MS to provide insights into the interaction. Protein profile changes in the brains of the zebrafish (Danio rerio) exposed to MP and Cd were further investigated using the proteomic approach. The correlation of gene expression on the transcription level of mRNA and the translation level of protein was examined by real-time quantitative PCR and Western blotting analysis. It showed that Cd and MP have an interaction on their bioaccumulation, which suggests that their joint effect over 96 h might be antagonistic. Proteomics revealed that 22 protein spots changed their expression levels under stress, of which 16 proteins were identified using MS. These proteins were involved in oxidation/reduction, metabolism, energy production, receptor activity, and cytoskeleton assembly. Among them, five proteins with a remarkable abundance change are significantly suggested to play important roles in the joint effect. This work demonstrates that there exists an interaction between MP and Cd toxicities, which may aid in our understanding of the mechanism of neurotoxicity induced by joint stress. The results may also provide the possibility of the establishment of candidate biomarkers for monitoring MP and Cd contamination in water.
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