Daily Archives: September 14, 2015

Are Differences in Water Treatment a Social Inequity?

There are several difficulties with this study which lead to misleading conclusions. A major premise of the study is that differences in treatment result from some municipalities being “deprived.” In reality, all of the municipalities have the same responsibility to decide what type of treatment to provide. Choices are made that lead to treatment differences. Communities as well as rural areas will make different choices. The suggestion that someone is being “deprived” as a result of the choices they make is rather misleading. Even more problematic is using 2 different proxies to draw a conclusion without consideration of actual exposure and risk.

Delpla I, Benmarhnia T, Lebel A, Levallois P, Rodriguez MJ. Investigating social inequalities in exposure to drinking water contaminants in rural areas. Environmental Pollution 2015 Sep 11;207:88-96. doi: 10.1016/j.envpol.2015.08.046.

Few studies have assessed social inequalities in exposure to drinking water contaminants. This study explores this issue in 593 rural municipalities of Québec, Canada. Quartiles of an ecological composite deprivation index were used as a proxy of socioeconomic status. Total trihalomethanes (TTHMs) and lead were chosen as proxies of chemical drinking water quality. The results show that the majority of deprived rural municipalities apply no treatment to their water (26%) or use a basic treatment (51%), whereas a relative majority of the wealthiest municipalities (40%) use advanced treatment. The proportion of municipalities having important lead (>5 μg/L) levels is highest in most deprived municipalities. Moreover, most deprived municipalities have a higher risk of high tap lead levels (RR = 1.33; 95%CI: 1.30, 1.36). Conversely, most deprived municipalities have a lower risk of high TTHMs levels (RR = 0.78; 95%CI: 0.69, 0.86). These findings suggest an environmental inequality in drinking water contaminants distribution in rural municipalities.