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Source identification of copper, lead, nickel, and zinc loading in wastewater reclamation plant influents from corrosion of brass in plumbing fixtures
2009
Kimbrough, David Eugene
A natural experiment indicated that a link between the presence and concentration of four elements, copper, lead, nickel, and zinc in the influent to two wastewater reclamation plants to the presence and concentrations of the same four elements in the tap water of residential properties. There were 36 populations of results that were assessed for the normality of their distribution, the difference in their median concentrations, the similarity in the ratios of their median concentrations, and the correlations of the concentrations. The results of this study suggest that brass corrosion is the major source of these four elements in the water reclamation plants influent and that there are two distinct populations of brass sources, those in the early stages of dezincification where the release of the non-copper elements is dominant and those in the later stages where the release of copper dominates and the type of brass that is corroding. Statistical analysis of residential tap waters and water reclamation plant influent showed that metals found in both came from brass corrosion.
显示更多 [+] 显示较少 [-]Levels and distribution of polybrominated diphenyl ethers (PBDEs) in the freshwater environment surrounding a PBDE manufacturing plant in China
2009
Xu, Jie | Gao, Zishen | Xian, Qiming | Yu, Hongxia | Feng, Jianfang
Polybrominated diphenyl ethers (PBDEs) were determined in muscle, liver and eggs of freshwater fishes and surface sediments from the Nongkang River in Jinhu, Jiangsu Province, China. The present study is the first to report PBDE concentrations in the freshwater environment surrounding a PBDE manufacturing plant in China. The concentrations of 13 PBDE congeners in muscle, liver and eggs of freshwater fishes ranged from <LOD to 130, <LOD to 252 and <LOD to 33.3 ng/g lipid wt, respectively, while the concentrations of 13 PBDE congeners in surface sediments from sewage outfall, upstream and downstream of the river were 52, 9.2, 7.1 ng/g organic carbon wt, respectively. Contamination by PBDEs in this area was not serious when compared with other regions of the world. A relatively high proportion of BDE-183 was found, consistent with the octa-BDE technical mixtures from the manufacturing plant by the side of the river. The first study to report concentrations of PBDEs in the freshwater environment surrounding a PBDE manufacturing plant in China.
显示更多 [+] 显示较少 [-]The impact of semiconductor, electronics and optoelectronic industries on downstream perfluorinated chemical contamination in Taiwanese rivers
2009
Lin, Angela Yu-Chen | Panchangam, Sri Chandana | Lo, Chao-Chun
This study provides the first evidence on the influence of the semiconductor and electronics industries on perfluorinated chemicals (PFCs) contamination in receiving rivers. We have quantified ten PFCs, including perfluoroalkyl sulfonates (PFASs: PFBS, PFHxS, PFOS) and perfluoroalkyl carboxylates (PFCAs: PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA) in semiconductor, electronic, and optoelectronic industrial wastewaters and their receiving water bodies (Taiwan's Keya, Touchien, and Xiaoli rivers). PFOS was found to be the major constituent in semiconductor wastewaters (up to 0.13 mg/L). However, different PFC distributions were found in electronics plant wastewaters; PFOA was the most significant PFC, contributing on average 72% to the effluent water samples, followed by PFOS (16%) and PFDA (9%). The distribution of PFCs in the receiving rivers was greatly impacted by industrial sources. PFOS, PFOA and PFDA were predominant and prevalent in all the river samples, with PFOS detected at the highest concentrations (up to 5.4 μg/L). The semiconductor, electronics and optoelectronic industries are the primary source of PFC contamination in downstream aqueous environments.
显示更多 [+] 显示较少 [-]Nitrous oxide supersaturation at the liquid/air interface of animal waste
2009
Makris, Konstantinos C. | Andra, Syam S. | Hardy, Michael | Sarkar, Dibyendu | Datta, Rupali | Bach, Stephan B.H. | Mullens, Conor P.
Concentrated animal feeding operations around the globe generate large amounts of nitrous oxide (N2O) in the surrounding atmosphere. Liquid animal waste systems have received little attention with respect to N2O emissions. We hypothesized that the solution chemistry of animal waste aqueous suspensions would promote conditions that lead to N2O supersaturation at the liquid/air interface. The concentration of dissolved N2O in poultry litter (PL) aqueous suspensions at 25 °C was 0.36 μg N2O mL−1, at least an order of magnitude greater than that measured in water in equilibrium with ambient air, suggesting N2O supersaturation. There was a nonlinear increase in the N2O Henry constants of PL from 2810 atm/mole fraction at 35 °C to 17 300 atm/mole fraction at 41 °C. The extremely high N2O Henry constants were partially ascribed to N2O complexation with aromatic moieties. Complexed N2O structures were unstable at temperatures > 35 °C, supplying the headspace with additional free N2O concentrations. Temperature-dependent N2O supersaturation at the liquid/air interface of animal waste.
显示更多 [+] 显示较少 [-]Do lagoons near concentrated animal feeding operations promote nitrous oxide supersaturation
2009
Makris, Konstantinos C. | Sarkar, Dibyendu | Andra, Syam S. | Bach, Stephan B.H. | Datta, Rupali
Animal wastewater lagoons nearby concentrated animal feeding operations (CAFOs) represent the latest tendency in global animal farming, severely impacting the magnitude of greenhouse gas emissions, including nitrous oxide (N₂O). We hypothesized that lagoon wastewater could be supersaturated with N₂O as part of incomplete microbial nitrification/denitrification processes, thereby regulating the N₂O partitioning in the gaseous phase. The objectives of this study were: (i) to investigate the magnitude of dissolved N₂O concentrations in the lagoon; and (ii) to determine the extent to which supersaturation of N₂O occurs in wastewater lagoons. Dissolved N₂O concentrations in the wastewater samples were high, ranging from 0.4 to 40.5 μg N2O mL⁻¹. Calculated dissolved N₂O concentrations from the experimentally measured partition coefficients were much greater than those typically expected in aquatic systems (<0.6 μg N₂O mL⁻¹). Knowledge of the factors controlling the magnitude of N₂O supersaturation could potentially bridge mass balance differences between in situ measurements and global N₂O models. Supersaturation of nitrous oxide may occur in lagoons near concentrated animal feeding operations.
显示更多 [+] 显示较少 [-]Removal of trace elements in three horizontal sub-surface flow constructed wetlands in the Czech Republic
2009
Kröpfelová, Lenka | Vymazal, Jan | Švehla, Jaroslav | Štíchová, Jana
Between March 2006 and June 2008 removal of 34 trace elements was measured on a monthly basis at three horizontal-flow constructed wetlands in the Czech Republic designed to treat municipal wastewater. In general, the results indicated a very wide range of removal efficiencies among studied elements. The highest degree of removal (average of 90%) was found for aluminum. High average removal was also recorded for zinc (78%). Elements removed in the range of 50-75% were uranium, antimony, copper, lead, molybdenum, chromium, barium, iron and gallium. Removal of cadmium, tin, mercury, silver, selenium and nickel varied between 25 and 50%. Low retention (0-25%) was observed for vanadium, lithium, boron, cobalt and strontium. There were two elements (manganese and arsenic) for which average outflow concentrations were higher compared to inflow concentrations. Reduced manganese compounds are very soluble and therefore they are washed out under anaerobic conditions. The paper describes the removal of trace elements in constructed wetlands treating municipal sewage.
显示更多 [+] 显示较少 [-]Immune modulation in the blue mussel Mytilus edulis exposed to North Sea produced water
2009
Hannam, M.L. | Bamber, S.D. | Sundt, R.C. | Galloway, T.S.
The discharge of oil well produced water (PW) provides a constant source of contaminants to the marine environment including polycyclic aromatic hydrocarbons, alkylated phenols, metals and production chemicals. High concentrations of PW cause adverse effects to exposed biota, including reduced survival, growth and reproduction. Here we explore the effects of PW on immune function in the blue mussel, Mytilus edulis. Mussels were exposed for 21 days to sublethal PW concentrations (0.125-0.5%) and cellular parameters were measured. Cell viability, phagocytosis and cytotoxicity were inhibited after exposure to 0.25% and 0.5% PW, whilst the 0.125% PW treatment produced significant increases in these biomarker responses. This biphasic response was only observed after 7 days exposure; longer exposure periods led to a reduction in immune parameters. Results indicate that PW concentrations close to the discharge point cause modulation to cellular immunity. The implications for longer-term disease resistance are discussed. Exposure to produced water alters immune function in the sentinel species Mytilus edulis.
显示更多 [+] 显示较少 [-]Combining passive samplers and biomonitors to evaluate endocrine disrupting compounds in a wastewater treatment plant by LC/MS/MS and bioassay analyses
2009
Liscio, C. | Magi, E. | Di Carro, M. | Suter, M.J.F. | Vermeirssen, E.L.M.
Two types of integrative sampling approaches (passive samplers and biomonitors) were tested for their sampling characteristics of selected endocrine disrupting compounds (EDCs). Chemical analyses (LC/MS/ MS) were used to determine the amounts of five EDCs (nonylphenol, bisphenol A, estrone, 17b-estradiol and 17a-ethinylestradiol) in polar organic chemical integrative samplers (POCIS) and freshwater mussels (Unio pictorum); both had been deployed in the influent and effluent of a municipal wastewater treatment plant (WWTP) in Genoa, Italy. Estrogenicity of the POCIS samples was assessed using the yeast estrogen screen (YES). Estradiol equivalent values derived from the bioassay showed a positive correlation with estradiol equivalents calculated from chemical analyses data. As expected, the amount of estrogens and EEQ values in the effluent were lower than those in the influent. Passive sampling proved to be the preferred method for assessing the presence of these compounds since employing mussels had several disadvantages both in sampling efficiency and sample analyses.
显示更多 [+] 显示较少 [-]Distribution of Particulate Nonylphenol in Lake Biwa, Japan
2009
Yoshida, Hiroo | Kudari, Shunsuke | Hori, Toshitaka | Sugiyama, Masahito
The distribution and geochemical behavior of nonylphenol (NP) in suspended and settling particles were studied in Lake Biwa, Japan. The vertical distribution of the particulate nonylphenol (PNP)/particulate organic carbon (POC) ratio showed a characteristic and hitherto unreported profile. The ratio was low at the surface, increased with depth to the middle layer before reaching a maximum at a depth of 45 or 65 m, and decreased toward the bottom. This profile is thought to have been due to the particulate organic matter (POM) in the lake being either freshly produced or aged POM and because the aged POM has a relatively higher affinity for NP compared to freshly produced POM. This idea was supported by the statistical analysis of physicochemical data (PNP, POC and chlorophyll a) and because the average PNP/POC ratio in the aged POM (2.24 x 10⁻⁵ g/g) was approximately four times higher than that of the freshly produced POM (0.63 x 10⁻⁵ g/g). The settling flux was estimated to be 2.2-6.4 μg/m²/day.
显示更多 [+] 显示较少 [-]Characterization of E1 Kraft Mill Effluent by Toxicity Identification Evaluation Methodology
2009
Reyes, F. | Chamorro, S. | Yeber, M. C. | Vidal, G.
In order to recover and reuse water in the Kraft mill process, evaluation of separate streams is required to identify toxic compounds or microcontaminants. The stage E1 Kraft effluent, corresponding to the first extraction step of the bleaching Kraft mill process, provides the main toxic compounds found in the final process effluent. This paper uses the toxicity identification evaluation (TIE) procedure for the physicochemical and ecotoxicological characterization of the E1 Kraft effluent. To distinguish the most important toxic compounds, a physicochemical characterization and Phase I of the TIE procedure were performed. The acute toxic effect of the E1 Kraft effluent and treated fraction was performed on Daphnia magna. Results show that untreated E1 Kraft effluent exerts an acute toxic effect on D. magna (24 h LC₅₀ = 27.6%), where the E1 Kraft effluent is characterized by pH 10.5, chemical organic demand (COD) 1,348.8 mg/l, and biological organic demand (BOD₅) 397.5 mg/l, while total phenolic compounds and color are 853.7 mg/l and 0.204 1 x 1 cm, respectively. Additionally, Cu⁺² (0.51 mg/l) and Fe⁺² (0.64 mg/l) were detected. With respect to different treatments, our results indicate that activated carbon, anionic and cationic exchange treatments were able to reduce more that 45% of E1 Kraft effluent's acute toxicity and that the ethylenediaminetetraacetic acid treatment was able to reduce the E1 Kraft effluent's acute toxicity to around 75% and the Cu⁺² concentration to 0.019 mg/l. Moreover, specific analysis of heavy metals and organic compounds by GC-MS show that the main compound responsible for the toxicity was Cu⁺², whose tolerance level on D. magna of the 0.12 mg/l.
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