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Robert Tardif Manuel Rodriguez Cyril Catto Ginette Charest-Tardif Sabrina Simard 《环境科学学报(英文版)》2017,29(8):163-172
The formation and concentration of disinfection by-products (DBPs) in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels (e.g., trihalomethanes (THMs), chloramines) and emerging DBPs (e.g., Halonitromethanes, Haloketones, NDMA) in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process: activation of ultraviolet (UV) photoreactor, halt of air stripping with continuation of air extraction from the buffer tank, halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate (PASS) coagulant. UV caused a high increase of Halonitromethanes (8.4 fold), Haloketones (2.1 fold), and THMs in the water (1.7 fold) and, of THMs in the air (1.6 fold) and contributed to reducing the level of chloramines in the air (1.6 fold) and NDMA in the water (2.1 fold). The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool. 相似文献
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An Ecology-Based Method for Defining Priorities for Large Mammal Conservation: The Tiger as Case Study 总被引:2,自引:0,他引:2
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Ginette Simon‐Sylvestre Marie‐France Rousseau 《Journal of environmental science and health. Part. B》2013,48(5):537-552
Abstract The depressive effect of metoxuron which is sometimes observed on nitrifying bacteria, evolves with time to become harmless a month later, under laboratory conditions. This phenomenon is explained by the present work carried out with two different soils, freshly sampled or airdried. Metoxuron disappeared very quickly in the soil; the kinetics of disappearance were similar for the two soils studied. This phenomenon, which results from a biological degradation, was not modified by supplying soil with ammoniacal nitrogen. 相似文献
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The objective of the present study was to determine the rat blood:air partition coefficients (P(b:a)) of chloroform, bromodichloromethane, dibromochloromethane and bromoform present in vitro individually or as mixtures. The experimentally determined P(b:a) of chloroform, bromodichloromethane, dibromochloromethane and bromoform present individually corresponded to (mean +/- SD, n = 8) 21.3 +/- 1.8, 41.8 +/- 6.2, 97.5 +/- 4.1, and 187 +/- 7.4, respectively. The P(b:a) of these trihalomethanes (THMs) showed a decreasing trend during mixed in vitro exposures to 0.138 +/- 0.002 or 0.273 +/- 0.002 micromol of each of the four THMs. In general, the P(b:a) determined during mixed exposures differed by < or = 15% of the average P(b:a) determined for THMs present individually. The results of this study suggest that an alteration of P(b:a) of the individual THMs is unlikely to occur at the blood concentrations of THMs observed during mixed exposures in rats. 相似文献
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Yazbeck C Kloppmann W Cottier R Sahuquillo J Debotte G Huel G 《Environmental geochemistry and health》2005,27(5-6):419-427
Objective: To evaluate health impact of boron in drinking water. Methods: A regional scale geographical study in Northern France was conducted. Assessment of boron blood levels in a group of 180
healthy individuals and correlation with boron content in drinking water were followed by an assessment of health indicators
such as birth rates, mortality rates, and sex ratios in zones of different boron content in drinking water. Results: After necessary adjustments, men living in municipalities with more than 0.30 mg/L of boron in drinking water had elevated
but not significant boron blood levels compared with those living in municipalities with boron water levels of less than 0.30 mg/L
(159.1 versus 123.0 ng/g; p > 0.05). The standardized birth ratio adjusted for the reference geographic zone and calendar time period was 1.07 and 1.28
in the low and high (>0.3 mg/L) boron content municipalities, respectively. The birth rate in municipalities with high boron
content in drinking water was higher than that of the reference geographic zone and of the French general population (p < 10-4). The standardized mortality ratio adjusted for the reference geographic zone and calendar time period was 0.94 and 0.92
in the low and high boron content municipalities, respectively. The mortality rate in municipalities with high boron content
in drinking water was less than that of the reference geographic zone and of the French general population (p < 10-3). No statistical difference was noted in the male–female sex ratios between the different municipality zones (p = 0.45). Conclusions: The results of this study do not support the idea of a deleterious effect of boron on human health, at the boron water level
contents found in this specific region. In fact, there is a tendency toward a beneficial effect with low-dose environmental
exposure (less than 1 mg/L of boron) in drinking water. 相似文献
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Mussel transplantation and biomarkers as useful tools for assessing water quality in the NW Mediterranean 总被引:12,自引:0,他引:12
Roméo M Hoarau P Garello G Gnassia-Barelli M Girard JP 《Environmental pollution (Barking, Essex : 1987)》2003,122(3):369-378
Mussels, coming from an aquaculture farm located in a clean open bay, were transplanted to several stations of the bays of Nice and Cannes (NW Mediterranean) including a reference site for one month at three periods. Several biomarkers: activities of glutathione S-transferase (GST; exposure to organics), of catalase (exposure to oxidative stress) and of acetylcholinesterase (inhibited by some pesticides) and the lipid peroxidation (thiobarbituric acid reactive substances: TBARS) were measured in transplanted mussels. Cd, Cu and Zn concentrations were also measured as well as their condition index. The results demonstrated some seasonal variations in GST and catalase activities with higher levels in June compared to October. The condition index was also higher in June than in October. Principal component analyses performed with the whole set of data allowed to separate stations or groups of stations according to their responses. The mussels from the harbour of Nice were characterized by high TBARS levels and catalase activity in October 1999 whereas in the harbour of Cannes, animals presented very high copper concentrations and GST activities in June 2000. At the reference site, mussels generally presented low enzymatic activities (except AChE activity) and peroxidation levels and low heavy metal concentrations. 相似文献
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