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11.
《环境科学学报(英文版)》2023,35(4):378-386
Quantification of regulated and emerging disinfection byproducts (DBPs) in swimming pool water, as well as the assessment of their lifetime health risk are limited in China. In this study, the occurrence of regulated DBPs (e.g., trihalomethanes, haloacetic acids) and emerging DBPs (e.g., haloacetonitriles, haloacetaldehydes) in indoor swimming pool water and the corresponding source water at a city in Eastern China were determined. The concentrations of DBPs in swimming pool water were 1-2 orders of magnitude higher than that in source water. Lifetime cancer and non-cancer risks of DBPs stemming from swimming pool water were also estimated. Inhalation and dermal exposure were the most significant exposure routes related to swimming pool DBP cancer and non-cancer risks. For the first time, buccal and aural exposure were considered, and were proven to be important routes of DBP exposure (accounting for 17.9%-38.9% of total risk). The cancer risks of DBPs for all swimmers were higher than 10−6 of lifetime exposure risk recommended by United States Environmental Protection Agency, and the competitive adult swimmers experienced the highest cancer risk (7.82 × 10−5). These findings provide important information and perspectives for future efforts to lower the health risks associated with exposure to DBPs in swimming pool water. 相似文献
12.
Sander P. M. Ganzevles Fons S. W. van Nuland Leo R. M. Maas Huub M. Toussaint 《Die Naturwissenschaften》2009,96(4):449-456
In nautical literature, ‘dead-water’ refers to the obstructive effect encountered by ships moving in stratified water due
to the ship generating waves on an interface that separates different water masses. To investigate the hypothesis that open
water swimming may also be obstructed by an encounter of dead-water, possibly causing drowning, we performed two experiments
that assess the impact of stratified water on swimming. In the first experiment, subjects made a single front-crawl stroke
while lying on a carriage that was rolling just above the water surface. The gain in kinetic energy, as a result of the stroke,
was far less in stratified than in homogeneous water. In the second experiment, four subjects swam a short distance (5 m)
in homogeneous and in two different settings of stratified water. At the same stroke frequency, swimming in stratified conditions
was slower by 15%, implying a loss in propulsive power by 40%. Although in nature stratification will be less strong, extrapolation
of the results suggests that dead-water might indeed obstruct swimming in open water as well. This effect will be most pronounced
during fair weather, when stratification of a shallow surface layer is most easily established. Our findings indicate that
swimmers’ anecdotal evidence on ‘water behaving strangely’ may have to be taken more seriously than previously thought. 相似文献
13.
Ichthyosaurs have been compared with the fast-swimming thunniform groups of marine vertebrates, tuna, lamnid sharks, and dolphins,
based on similarity of shape of the body and locomotory organs. In addition to shape, high-tensile stiffness of the control
surfaces has been shown to be essential in maximizing hydrodynamic efficiency in extant thunniform swimmers. To date, there
has been no evidence of a stiffening support system for the dorsal fin and dorsal lobe of the caudal fin in ichthyosaurs,
the sole stiffening structure of the ventral lobe being an extension of the vertebral column along its leading edge. Stenopterygius SMF 457 is arguably the best soft-tissue preserved ichthyosaur specimen known. Here, we examine soft-tissue preservation
in this specimen in the control surfaces and provide the first evidence of a complex architecture of stiff fibers in the dorsal
and caudal fins. We find by comparisons and by analogy that these fibers provided a remarkable mechanism for high tensile
stiffness and efficiency of the locomotory organs virtually identical to that of the great white shark, Carcharodon carcharias. It is the first mechanostructural study of the control surfaces of a Jurassic ichthyosaur that adds essential evidence in
support of the view that these forms were high-speed thunniform swimmers. 相似文献
14.
Qi Zheng Lindsay K. Jmaiff Blackstock Wenchao Deng Hailin Wang X. Chris Le Xing-Fang Li 《环境科学学报(英文版)》2017,29(3):322-325
正Swimming is excellent exercise and offers many health benefits.However,the"chlorine smell"in swimming pools may be a turn-off for some people.Although this smell is often thought to be of chlorine,it actually comes from volatile compounds that are produced from unintended reactions between disinfectants(e.g.,chlorine)and organic matter in 相似文献
15.
通过对深圳七家游泳池水中三氯甲烷的监测,三氯甲烷超标严重(52%超标,最高超标4倍)对对卤代烃的形成及其影响因素进行探讨,提醒人们不要忽视来自游泳池中的有机污染。 相似文献
16.
参照国家标准《公共场所卫生指标及限值要求》(GB 37488—2019),在游泳池布设6个采样点,采用计算机远程实时在线监测游泳池水pH值、游离余氯、细菌总数、大肠菌群、尿素、浑浊度、温度等指标,用自动调控装置进行水质净化处理,并将该自控技术和人工检测与净化手段作比对。结果表明:计算机远程在线监测能实时了解水质状况,远程集中管理节约人力成本;游泳池水质参数指标超出安全值时,自控装置会自动预警和报警并自动施药和注水,施药精准度较高,安全性能较好;游泳池水质随着温度和人数变化具有较大的差异性,采用人工手段和自控技术监测与净化相结合的方式管理游泳池,安全系数更高。 相似文献
17.
Alvyn P. Berg Ting-An Fang Hao L. Tang 《Frontiers of Environmental Science & Engineering》2019,13(1):10
18.
The main objective of the present study was to investigate possible links between biomarkers and swimming performance in the estuarine fish Pomatoschistus microps acutely exposed to metals (copper and mercury). In independent bioassays, P. microps juveniles were individually exposed for 96 h to sub-lethal concentrations of copper or mercury. At the end of the assays, swimming performance of fish was measured using a device specially developed for epibenthic fish (SPEDE). Furthermore, the following biomarkers were measured: lipid peroxidation (LPO) and the activity of the enzymes acetylcholinesterase (AChE), lactate dehydrogenase (LDH), glutathione S-transferases (GST), 7-ethoxyresorufin-O-deethylase (EROD), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPx). LC50s of copper and mercury (dissolved throughout metal concentrations) at 96 h were 568 μg L−1 and 62 μg L−1, respectively. Significant and concentration-dependent effects of both metals on swimming resistance and covered distance against water flow were found at concentrations equal or higher than 50 μg L−1 for copper and 3 μg L−1 for mercury (dissolved throughout metal concentrations). These results indicate that SPEDE was efficacious to quantify behavioural alterations in the epibenthic fish P. microps at ecologically relevant concentrations. Significant alterations by both metals on biomarkers were found including: inhibition of AChE and EROD activities, induction of LDH, GST and anti-oxidant enzymes, and increased LPO levels, with LOEC values ranging from 25 to 200 μg L−1 for copper and from 3 to 25 μg L−1 for mercury (dissolved throughout metal concentrations). Furthermore, significant and positive correlations were found between some biomarkers (AChE and EROD) and behavioural parameters, while negative correlations were found for others (LPO, anti-oxidant enzymes and LDH) suggesting that disruption of cholinergic function through AChE inhibition, decreased detoxification capability due to EROD inhibition, additional energetic demands to face chemical stress, and oxidative stress and damage may contribute to decrease the swimming performance of fish. Since a reduced swimming capability of fish may reduce their ability to capture preys, avoid predators, and interfere with social and reproductive behaviour, the exposure of P. microps to copper and/or mercury concentrations similar to those tested here may decrease the fitness of wild populations of this species. 相似文献
19.
In water, chlorine reacts with nitrogen-containing compounds to produce disinfection by-products such as nitrogen trichloride which induces ocular and respiratory irritations in swimming pool workers. This study proposes a model to predict variations in NCl3 concentration over time in a traditional indoor swimming pool as a function of its operating parameters and attendance. The model was developed taking into consideration the reaction mechanisms, thermodynamic equilibria, physico-chemical properties, and transfer mechanisms occurring at the pool's surface. This model was validated through a robust series of experiments over two days and two nights in a real swimming pool. The model was found to satisfactorily predict variations over time in the concentrations of the chemical species investigated, including nitrogen trichloride. The work presented constitutes a first step to extend the model at different swimming pools. This approach may also be used to study the influence of the main operating parameters and to evaluate the impact of setting up water treatment systems on nitrogen trichloride concentration. 相似文献
20.
Disinfection of water for human use is essential to protect against microbial disease; however, disinfection also leads to formation of disinfection by-products (DBPs), some of which are of health concern. From a chemical perspective, swimming pools are a complex matrix, with continual addition of a wide range of natural and anthropogenic chemicals via filling waters, disinfectant addition, pharmaceuticals and personal care products and human body excretions. Natural organic matter, trace amounts of DBPs and chlorine or chloramines may be introduced by the filling water, which is commonly disinfected distributed drinking water. Chlorine and/or bromine is continually introduced via the addition of chemical disinfectants to the pool. Human body excretions (sweat, urine and saliva) and pharmaceuticals and personal care products (sunscreens, cosmetics, hair products and lotions) are introduced by swimmers. High addition of disinfectant leads to a high formation of DBPs from reaction of some of the chemicals with the disinfectant. Swimming pool air is also of concern as volatile DBPs partition into the air above the pool. The presence of bromine leads to the formation of a wide range of bromo- and bromo/chloro-DBPs, and Br-DBPs are more toxic than their chlorinated analogues. This is particularly important for seawater-filled pools or pools using a bromine-based disinfectant. This review summarises chemical contaminants and DBPs in swimming pool waters, as well as in the air above pools. Factors that have been found to affect DBP formation in pools are discussed. The impact of the swimming pool environment on human health is reviewed. 相似文献