Derry C W, Bourne D E, Sayed A R
Department of Community Health, School of Life Sciences, Cape Technikon.
S Afr Med J. 1990 May 19;77(10):522-4.
A number of studies carried out in other countries have shown the existence of negative correlations between cardiovascular disease mortality and the hardness of water supplies. A study here showed negative correlation (P less than 0.10) between cardiovascular disease mortality for the South African urban white population and total water hardness (equivalent calcium carbonate mg/l). Negative correlations were also found to exist with the hardness-associated factors potassium (P less than 0.05), sulphate (P less than 0.05) and chloride (P less than 0.05) and manganese (P less than 0.10). The results are described in terms of existing studies and a number of local problems have been identified and discussed.
在其他国家开展的一些研究表明，心血管疾病死亡率与供水硬度之间存在负相关关系。这里的一项研究显示，南非城市白人人口的心血管疾病死亡率与总水硬度（碳酸钙毫克/升当量）之间存在负相关（P小于0.10）。还发现与硬度相关的因素钾（P小于0.05）、硫酸盐（P小于0.05）、氯化物（P小于0.05）和锰（P小于0.10）之间存在负相关。根据现有研究对结果进行了描述，并确定和讨论了一些当地问题。
