From Legionella bacteria and Non-tuberculous mycobacteria, safe transport of mains water depends on best practice and good policy, environmental health experts say.

However, Flinders University academics warn current systems and legislation may not always be supported by solid scientific research or best practice in public health.

“There are major inconsistencies in Australia, and overseas jurisdictions, in managing Legionella and other contaminants in water systems,” says Flinders University Associate Professor Richard Bentham, who will present on possible shortfalls in Legionella disease policy at the Environmental Health Australia (EHA) National Conference in Adelaide (6-8 November 2019).

“For example, some of the requirements, to keep cold-water systems at the European standard well below 20C, is not always possible in Australia.

“Other policy settings on warm-water, hot- and cold-water systems are not always based on evidence-based science, and usually rely solely on a localised tick-box protocol, which opens the gate for all sorts of things to happen.”

Environmental health experts, including Dr Bentham, also warn that some positive policy changes can lead to other potential problems.

“For example, the removal of all lead-based tapware and pipeline systems, as introduced recently in Victorian schools, might inadvertently lead to increased public health risk from microbial contamination, such as opportunistic premise plumbing pathogens (OPPPs),” Dr Bentham and colleagues say in a new scientific article.

“We recommend that future research into plumbing materials also weigh up its effect on OPPPs such as Non-tuberculous mycobacterium (which can cause serious pulmonary illness) ahead of changes in legislation.”

Any changes in regulation regarding materials for potable water infrastructure need to be evidence based and must consider all potential risks to public health, the paper concludes.

“The complexities of water quality, materials of construction, microbial contamination, and public health risks are not well understood. For example, current data indicates limited scientific evidence to support the removal of brass fittings as a means of reducing lead exposures.”

See ‘Public health risks associated with heavy metal and microbial contamination of drinking water in Australia’ by PJ Molino, R Bentham, MJ Higgins, J Hinds and H Whiley has been published in the open access International Journal of Environmental Research and Public Opinion (Issue 20, Article 3982).

Flinders adjunct academic Dr Bentham, who is also associate director of Built Water Solutions, has consulted extensively around Australia on Legionella risk assessment and management.

Other Flinders University experts to present at the 44^th EHA National Conference this week include:

• Methamphetamine and other drug residues from clandestine labs and illicit drug use can lead to chemical contamination of properties. Flinders Professor Paul Kirkbride and consultant Dr Jackie Wright will support a masterclass on systems to dealing with this growing issue.
• Flinders senior lecturer Dr Kirstin Ross and Professor Jim Smith will discuss the importance of local government, policy, and environmental health officers in keeping the community safe.
• Salmonella and bacterial gastroenteritis food poisoning pose a risk to human health. Flinders researchers Dr Harriet Whiley, Dr Thilini Keerthirathne and Jessica Dennis will cover some of the common risks.
• South Australia leads the nation in regional community wastewater recycling using high-rate algal ponds to treat contaminants. Flinders research leader Professor Howard Fallowfield will outline examples at Kingston-on-Murray and the Mid North.

“Climate change and our ageing population are putting increasing pressure on environmental health standards,” says Dr Kirstin Ross, who helped convene the conference.

“Allergens, extreme heat and increasing frequency of natural disasters, and changing patterns of infectious diseases – from food, water, air and vector-borne – are increasingly becoming major environmental health threats,” she says, adding there is a growing shortage of environmental health officers.