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Application of bioassays to evaluate a copper contaminated soil before and after a pilot-scale electrokinetic remediation
2009
Wang, Quan-Ying | Zhou, Dong-Mei | Cang, Long | Sun, Tian-Ran
Remediation programmes are considered to be complete when human risk-based criteria are met. However, these targets are often unsatisfied with the ecological parameters that may be important with regard to future soil use. Five soil subsamples, collecting along a pilot-scale soil column after electrokinetic treatment, were studied, from which about 42.0%-93.3% soil Cu had been successfully removed. A series of biological assays including soil microbial biomass carbon, basal soil respiration, soil urease activity, earthworm assays, and seed assays were used to evaluate their ecological risks. The results showed that the bioassay data from the treatment variants did not supposedly reflecting the decreased soil Cu concentrations after the electrokinetic treatment, but were highly correlated with some soil physicochemical characteristics. It suggests that bioassays are necessary to assess the ecotoxicity of soil after electrokinetic treatment.
Show more [+] Less [-]Modelling the risk of Pb and PAH intervention value exceedance in allotment soils by robust logistic regression
2009
Soils of allotments are often contaminated by heavy metals and persistent organic pollutants. In particular, lead (Pb) and polycyclic aromatic hydrocarbons (PAHs) frequently exceed legal intervention values (IVs). Allotments are popular in European countries; cities may own and let several thousand allotment plots. Assessing soil contamination for all the plots would be very costly. Soil contamination in allotments is often linked to gardening practice and historic land use. Hence, we predict the risk of IV exceedance from attributes that characterize the history and management of allotment areas (age, nearby presence of pollutant sources, prior land use). Robust logistic regression analyses of data of Swiss allotments demonstrate that the risk of IV exceedance can be predicted quite precisely without costly soil analyses. Thus, the new method allows screening many allotments at small costs, and it helps to deploy the resources available for soil contamination surveying more efficiently. The contamination of allotment soils, expressed as frequency of intervention value exceedance, depends on the age and further attributes of the allotments and can be predicted by logistic regression.
Show more [+] Less [-]Exposure assessment of French women and their newborn to brominated flame retardants: Determination of tri- to deca- polybromodiphenylethers (PBDE) in maternal adipose tissue, serum, breast milk and cord serum
2009
Antignac, Jean-Philippe | Cariou, Ronan | Zalko, Daniel | Berrebi, A (Alain) | Cravedi, Jean-Pierre | Maume, Daniel | Marchand, Philippe | Monteau, Fabrice | Riu, Anne | Andre, François
In the frame of a French monitoring program, tri- to deca- polybromodiphenylethers (PBDE) have been measured in maternal and cord serum, adipose tissue, and breast milk samples, collected from 93 volunteer women during caesarean deliveries. The seven major tri- to heptaBDE (BDE-28, 47, 99, 100, 153, 154, and 183) were detected in adipose tissue and breast milk with cumulated median values of 2.59 and 2.51 ng g-1 l w. Nine highly brominated octa- to decaBDE (BDE-196, 197, 201, 202, 203, 206, 207, 208 and 209) was performed in the same samples, with cumulated median values of 2.73 and 3.39 ng g-1 l w in adipose tissue and breast milk, respectively. At this opposite, median levels of octa- to decaBDE in maternal and cord serum appeared significantly higher than the levels of tri- to heptaBDE in the same matrices, i.e. 8.85 and 12.34 versus 0.98 and 0.69 ng g-1 l w, respectively. This study provides the first data at the French level regarding the occurrence of PBDE in human, and demonstrates the exposure of both human foetus at late stage of pregnancy and newborn at early stages of life through breastfeeding with special emphasis on the presence of highly brominated compounds.
Show more [+] Less [-]Relationship of urinary arsenic metabolites to intake estimates in residents of the Red River Delta, Vietnam
2009
Agusa, Tetsuro | Kunito, Takashi | Minh, Tu Binh | Trang, Pham Thi Kim | Iwata, Hisato | Viet, Pham Hung | Tanabe, Shinsuke
This study investigated the status of arsenic (As) exposure from groundwater and rice, and its methylation capacity in residents from the Red River Delta, Vietnam. Arsenic levels in groundwater ranged from <1.8 to 486 μg/L. Remarkably, 86% of groundwater samples exceeded WHO drinking water guideline of 10 μg/L. Also, estimated inorganic As intake from groundwater and rice were over Provisional Tolerable Weekly Intake (15 μg/week/kg body wt.) by FAO/WHO for 92% of the residents examined. Inorganic As and its metabolite (monomethylarsonic acid and dimethylarsinic acid) concentrations in human urine were positively correlated with estimated inorganic As intake. These results suggest that residents in these areas are exposed to As through consumption of groundwater and rice, and potential health risk of As is of great concern for these people. Urinary concentration ratios of dimethylarsinic acid to monomethylarsonic acid in children were higher than those in adults, especially among men, indicating greater As methylation capacity in children.
Show more [+] Less [-]Persistence of organochlorine chemical residues in fish from the Tombigbee River (Alabama, USA): Continuing risk to wildlife from a former DDT manufacturing facility
2009
Hinck, Jo Ellen | Norstrom, Ross J. | Orazio, Carl E. | Schmitt, Christopher J. | Tillitt, Donald E.
Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p'- and o,p′-DDT isomer concentrations and o,p'- versus p,p'-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbee River. Concentrations of p,p'-DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations from a national program. Total DDT in McIntosh bass exceeded dietary effect concentrations developed for bald eagle and osprey. Hexachlorobenzene, PCBs, and toxaphene concentrations in bass from McIntosh also exceeded thresholds to protect fish and piscivorous wildlife. Whereas concentrations of DDT and most other organochlorine chemicals in fish have generally declined in the U.S. since their ban, concentrations of DDT in fish from McIntosh remain elevated and represent a threat to wildlife.
Show more [+] Less [-]Influence of toxic cyanobacteria on community structure and microcystin accumulation of freshwater molluscs
2009
Gerard, Claudia | Poullain, Virginie | Lance, Emilie | Acou, Anthony | Brient, Luc | Carpentier, Alexandre
Community structure and microcystin accumulation of freshwater molluscs were studied before and after cyanobacterial proliferations, in order to assess the impact of toxic blooms on molluscs and the risk of microcystin transfer in food web. Observed decrease in mollusc abundance and changes in species richness in highly contaminated waters were not significant; however, relative abundances of taxa (prosobranchs, pulmonates, bivalves) were significantly different before and after cyanobacterial bloom. Pulmonates constituted the dominant taxon, and bivalves never occurred after bloom. Microcystin accumulation was significantly higher in molluscs from highly (versus lowly) contaminated waters, in adults (versus juveniles) and in pulmonates (versus prosobranchs and bivalves). Results are discussed according to the ecology of molluscs, their sensitivity and their ability to detoxify.
Show more [+] Less [-]Genotoxicity of water from the Songhua River, China, in 1994-1995 and 2002-2003: Potential risks for human health
2009
Liu, Jia-Ren | Dong, Hong-Wei | Tang, Xuan-Le | Sun, Xiang-Rong | Han, Xiao-Hui | Chen, Bing-Qing | Sun, Chang-Hao | Yang, Bao-Feng
A previous study showed that the cancer mortalities are higher for residents who lived nearby the Songhua River heavily polluted by organic contamination. It is important to determine its risk of carcinogenic potential. Short-term genotoxic bio-assays using Salmonella, Sister Chromatid Exchange (SCE), and Micronuclei (MN) assays were employed to examine the genotoxic activity of ether extracts of water samples taken from the Songhua River. The results of the Salmonella bioassay indicated that there were indirect frame-shift mutagens in the water samples. A dose-response relationship for the SCE and MN assays was obtained. These results showed that organic extracts of water samples have genotoxic activity and the risk of carcinogenic potential to human health. The mutagenesis of water samples had changed compared to the results in 1994-1995. An increasing trend of risk of carcinogenic potential in the Songhua River after ten years should be noted and needs to be studied further.
Show more [+] Less [-]Determination of BTEX by GC-MS in Air of Offset Printing Plants: Comparison between Conventional and Ecological Inks
2009
Godoi, Ana F. L | Sawada, Eliza Y | de Marchi, Mary Rosa R | Van Grieken, René | Godoi, Ricardo H. M
The use of inks containing organic solvents by the offset printing process implies in the release of volatile organic compounds to the work environment. Many of these compounds such as benzene, toluene, ethylbenzene, and the xylene isomers (well known by the acronym BTEX) are extremely toxic. In this study, the BTEX concentrations were determined in two different printing plants that use distinct types of inks: the conventional and the so-called ecological, which is manufactured based on vegetal oil. Concentration ranges were 43-84, 15-3,480, 2-133, 5-459, and 2-236 μg m⁻³ for benzene, toluene, ethylbenzene, m + p-xylene, and o-xylene, respectively, for the conventional printing plant. At the ecological printing plant, concentration ranges were below limit of detection (<LD)-31, <LD-618, <LD-1,690, <LD-10,500, <LD-3,360 μg m⁻³ for benzene, toluene, ethylbenzene, m + p-xylene, and o-xylene, respectively. BTEX concentrations are lower at the ecological printing environment than in the conventional, where mineral oil-based inks are used. However, the worker who cleans the printing matrices is exposed to high concentrations of ethylbenzene and xylenes, due probably to the cleaning product's composition (containing high amounts of BTEX). Although the BTEX concentrations found in both printing work environments were below the limits considered by the Brazilian Law for Activities and Unhealthy Operations (NR-15), the exposure to such vapors characterizes risk to the workers' health for some of the evaluated samples, mainly the personal ones.
Show more [+] Less [-]An Environmental Risk Assessment of Radon in Lantian Karst Cave of Shaanxi, China
2009
Lu, Xinwei | Li, Loretta Y. | Zhang, Xiaolan
The radiation dose and environmental health risk of radon concentration in the Lantian karst cave of China to guides and visitors were estimated based on the continuous radon concentration monitoring. Distinct seasonal variations were observed in the radon concentration of the air inside the cave. The maximum concentration occurred in the summer, whereas the minimum radon concentration occurred during the winter. The annual average radon concentration in the caves investigated is slightly higher than the upper bound of radon action level for underground space used in China and less than the upper bound of radon action level recommended by the International Commission on Radiation Protection (ICRP) for workplaces. The annual effective dose to tour guides working in two investigated caves varies from 4.1 to 16.5mSv, depending on different equilibrium factors together with different dose conversion factors proposed in the literature. The annual maximum time that a tour guide or other worker can safely be inside the cave is estimated to be 1,250 or 2,246h, depending on whether one bases this on the high or mean radon concentration, with an equilibrium factor of one in both cases. Given the synergistic effects of smoking, tour guides who are smokers should be in the cave only 10-20% of these hours. In all cases, the annual effective doses to visitors are well below the 1mSv maximum suggested dose for a member of the public for 1 year.
Show more [+] Less [-]Monitoring BTEX and Aldehydes in Car Exhaust from a Gasoline Engine During the Use of Different Chemical Cleaners by Solid Phase Microextraction-Gas Chromatography
2009
Niri, Vadoud H. | Mathers, James B. | Musteata, Marcel F. | Lem, Stan | Pawliszyn, Janusz
All commercial gasoline fuels build up deposits on the spark plugs, injectors, oxygen sensors, catalytic converter, and inside the combustion chamber, which will lower the engine's performance and increase air pollution. As a result, fuel-based detergents have been developed to prevent and remove unwanted deposits. Unfortunately, many of the detergents use high amounts of aromatic solvents, which result in a greater risk of exposure to aromatic compounds like benzene. In this study, car exhaust was analyzed for benzene, toluene, ethylbenzene, and xylenes (BTEX), as well as formaldehyde and acetaldehyde during engine cleaning service using different chemical cleaners. A special device was designed for sampling from car exhaust using solid phase microextraction. The extracted compounds were analyzed using a gas chromatograph with flame ionization detector. The cleaning products were rated with regard to the amount of pollutants produced during the cleaning service.
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