A critical assessment of epidemiological studies for the investigation of the health risk of drinking untreated rainwater

ABSTRACT

Rainwater has been used for many purposes globally including drinking, however whether untreated rainwater is a risk factor for health problems remains inconclusive. Rainwater tanks generally serve households and in many instances illness may not be reported. There are some published studies which have investigated the role of rainwater in the occurrence of illness. Additionally, several outbreaks associated with rainwater have been reported in the literature. The many epidemiological study designs which have been used in these investigations will be discussed. This paper will critically assess the advantages and limitations of the various epidemiological designs and present a design which may provide a more conclusive answer to the role of rainwater on the health of persons who use it for drinking. A current randomized controlled trial assessing the risk associated with drinking untreated rainwater amongst people who choose rainwater as their primary source of drinking water will be discussed.