I'm happy to report that I agree wholeheartedly with Roger Masters that we humans have a biological rather than a socially constructed need for water. In fact, Prof. Masters and I are so much in agreement on this point that I don't feel it necessary to consult “the literature on mammalian biological needs” as he suggests. As a mammal myself, I firmly believe that I would die were I denied water for a sufficient length of time, though I plan on keeping this an untested hypothesis.

I'm also happy to report that I agree with Prof. Masters that water pollution, and its myriad causes, is a serious issue that adversely affects the lives of millions of people. Had water pollution been the subject of my article, Prof. Masters would have seen that we do in fact agree that it's a problem. My article (PS, January 2007, 49–54) was instead a critique of a specific literature that regards water privatization as a threat to the human right to water. Prof. Masters' contention that privatization is irrelevant to water quality is itself somewhat irrelevant to the literature I addressed in my article, though I would direct him to the excellent article I cite by Jennifer Davis (2005), which finds that “Case-based evidence in several OECD countries suggests that privatization has helped utilities achieve compliance with water quality and wastewater treatment standards” (163).

Prof. Masters' main critique of my article appears to be that, if the need for water is conceived of as a social construct and thus entirely relative, it provides no solid moral ground upon which we can say that it is bad to pollute water. This is a gross misrepresentation of my original article, but it does raise some interesting questions, since the ostensible solution to water pollution—establishing water quality standards and a regulatory body to enforce those standards—rests upon a definition of “quality” water that is in fact socially constructed.

An excellent case-in-point is the controversy surrounding the Environmental Protection Agency's decision at the end of the Bill Clinton administration to change the permissible level of arsenic in drinking water from 50 to 10 parts per billion, and the incoming George W. Bush administration's decision to postpone that decision for further study. The controversy involved not only the likely effects of low levels of arsenic on human health, but also the cost, particularly to small water companies, of system upgrades to meet the new standard, relative to the benefits of reduced cancer rates in susceptible persons, who could conceivably be supplied with bottled water at a relatively low cost.

Regardless of one's opinion about how much arsenic should be permitted in drinking water, the larger point is that binding definitions of permissible levels of any pollutant are socially constructed definitions of “quality” water. Arsenic is particularly instructive as an example because it is an element that occurs naturally and is used in various ways in industry, mining, and agriculture. Thus, depending on the source of the arsenic, lowering permissible levels can be either a process of altering “natural” water to create a socially-defined form of “quality,” or a process of reversing the effects of human actions to bring water back to its “natural” state. In either case, water becomes inextricably tied to definitions of “nature” and “quality” that are only partially related to mammalian biological need. If Prof. Masters is making an argument for better water quality standards, he is just as guilty of engaging a social construction as am I.