OPINION LETTERS

摘要

Fred Pearce describes a key caveat to announcements in 2010 that the Millennium Development Goal target for access to safe drinking water had been met (12 April, p 12). In his article, I am quoted as saying that the World Health Organization has been silent on this issue. To clarify, I was referring to the fact that there has been no formal response to published estimates of the gap between what is "improved" and what is "safe". The WHO/UNICEF-supported Joint Monitoring Programme, which measures global progress towards water and sanitation targets, has repeatedly articulated that access to an "improved" water source is a useful but imperfect metric, quite different from more direct measures of microbiological or chemical water safety.