Saliba L J, Helmer R
WHO/EURO Project Office, Athens, Greece.
World Health Stat Q. 1990;43(3):177-87.
A number of bacterial, viral and other diseases can be contracted by man through exposure to sewage-polluted bathing-water or beach sand. The increasing use of the sea for recreation has led to major concern regarding health hazards to both local and tourist populations. Epidemiological studies attempting to correlate microbiological water quality with health effects have produced different results, leading to a wide variation in recreational water quality criteria and standards applied, and to considerable controversy regarding their implementation. The Mediterranean provides a good example of a problem region where health risks are accentuated as a result of high utilization of bathing areas coupled with long exposure periods. Coastal pollution by sewage is still a major concern and control measures vary considerably. A number of microbiological/epidemiological studies have been carried out since 1953 in an attempt to define the levels of risk following exposure to different concentrations of bacteria in bathing waters. Most of these have been prospective studies whose design involved subject recruitment on the beach itself, classification of swimmers on the basis of immersion of the head in the water, and follow-up interviews after 7-10 days, together with a system for validation of gastrointestinal symptomatology. Practically all studies showed higher morbidity among bathers as compared to non-bathers, but correlation between specific symptoms and bacterial indicator concentrations varied considerably. On the basis of the 1972-1978 Cabelli Environmental Protection Agency (EPA) study in the United States of America, later developed by EPA into a recommended health-effects criterion for marine recreational waters, one would expect 25-40 gastrointestinal cases per 1,000 persons exposed to seawater containing 100 enterococci per 100 ml. Extrapolation of these figures to annual bathing populations indicates the potential magnitude of the problem. Much more work is needed however before a satisfactory dose-response relationship is obtained, principally because of confounding factors inherent in all studies carried out so far, which still require a solution.
人类接触受污水污染的浴场用水或沙滩时，可能感染多种细菌、病毒及其他疾病。人们越来越多地利用海洋进行娱乐活动，这引发了对当地居民和游客健康危害的重大关注。旨在将微生物水质与健康影响相关联的流行病学研究产生了不同结果，导致所应用的娱乐用水水质标准和规范差异很大，在其实施方面也存在相当大的争议。地中海就是一个问题区域的典型例子，由于浴场利用率高且暴露时间长，健康风险加剧。污水造成的沿海污染仍是主要问题，控制措施差异很大。自1953年以来，已经开展了多项微生物学/流行病学研究，试图确定接触不同浓度浴场水中细菌后的风险水平。其中大多数是前瞻性研究，其设计包括在海滩上招募受试者，根据头部浸入水中的情况对游泳者进行分类，7至10天后进行随访访谈，以及一套用于验证胃肠道症状的系统。几乎所有研究都表明，游泳者的发病率高于非游泳者，但特定症状与细菌指标浓度之间的相关性差异很大。根据美国环境保护局（EPA）1972 - 1978年的研究（后来EPA将其发展为海洋娱乐用水的推荐健康影响标准），每100毫升海水中含有100个肠球菌时，预计每1000名接触海水的人中会出现25 - 40例胃肠道病例。将这些数字推算到每年的游泳人群中，可看出问题的潜在规模。然而，在获得令人满意的剂量反应关系之前，还需要开展更多工作，主要是因为迄今为止所有研究中都存在混杂因素，这些因素仍有待解决。
