Monash researchers question the safety of tank water

January 2007

Prof Don Bursill (CEO, CRC for Water Quality and Treatment) and Peter Donlon (Technical Director, Water Services Association of Australia), with project leader Dr Karin Leder (left), Professor John McNeil (right) and Dr Martha Sinclair (2nd from right).

Monash medical researchers are collaborating with other scientists nationally to assess the safety of drinking water and in particular, tank water.

Since rainwater is the primary source of drinking water for 11% of Australian households, it is normally accepted as a relatively safe source of water in the absence of a disinfected tap water supply.

However, rainwater is subject to intermittent contamination by microbial pathogens carried by birds and small animals which have access to rooftops.

The increasing proliferation of rainwater tanks in urban areas is likely to lead to increased rainwater consumption, because of the “pure and natural” image of this water source.

Alumnus Dr Karin Leder, Head of the Infectious Disease Epidemiology Unit in Department of Epidemiology and Preventive Medicine (DEPM), is coordinator of the public health component of the research and Dr Martha Sinclair is a Senior Research Fellow on the study.

“Rigorous data on the safety of drinking untreated rainwater is lacking, so the Collaborative Research Centre (CRC) at DEPM is undertaking a double-blinded randomised trial to determine whether microbial pathogens in untreated rainwater make a significant contribution to gastroenteritis in people who consume such water,” Dr Leder said.

The study has been primarily funded by the National Health and Medical Research Council, with additional funding for the water quality testing component being provided by the CRC for Water Quality and Treatment.  The South Australian Department of Health is also involved in the study and will host the study office in Adelaide.

Three hundred households in and around Adelaide will be recruited and assigned either real or sham water treatment units to treat rainwater used for drinking and cold food preparation.  The real units will contain a filter and ultraviolet unit to remove microbes, while the sham units will appear the same but be non-functional.  Families will record their health status in diaries for a period of 12 months, and rates of gastroenteritis in the real and sham groups will then be compared to see whether the removal of micro-organisms from rainwater affected health outcomes.

The pilot study phase is currently underway and the main study will commence in February 2007.

More information about the CRC for Water Quality and Treatment