Decades-old asbestos cement pipes are wearing out and bursting in some Canadian communities, and a recent TV news program is raising questions about the potential health risks of asbestos fibres in drinking water.
Asbestos cement, or A-C pipes, were initially preferable for their low-cost and durability, but were discontinued for installation in the 1970s. They were thrust into the spotlight this month following recent coverage on CTV’s W5 investigative news program.
Of the 100 communities across Canada that W5 staff reached out to, 85 responded that A-C pipes continue to deliver water to parts of the community.
The general assertion from the activist prominently featured in the episode is that A-C pipes are “out of sight, out of mind” and not an issue on municipal radars, despite the potential risks to health remaining unclear.
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While concerns about airborne exposure to asbestos are well-documented, the news program says there is no general consensus about the effects of ingesting the fibres through drinking water, and particularly, the impacts of burst or broken A-C pipes on the water supply. W5, however, refers viewers to several international studies that show elevated risks of cancer, including mesothelioma.
The Canadian Water and Wastewater Association (CWWA) has put together speaking notes on asbestos-cement water pipes, for utilities and municipalities that may be receiving questions or concerns from residents/customers.
According to the CWWA, while no direct plans from governments exist to target the removal of A-C pipes, “it is recommended”, and a “generally-accepted practice” that A-C pipes be removed “during construction that exposes such pipe.”
The greatest known health threat when it comes to A-C pipes, may be to workers making repairs, states the CWWA.
“Utility workers are at the greatest risks due to airborne dust, and therefore, most wear appropriate PPE when cutting into A-C pipe,” states the CWWA.
CWWA also noted that while asbestos fibres have been found to transfer to the air through showers and humidifiers, it is a very low percentage.
The episode does note Health Canada’s stance on the issue, which is that there is no “consistent, convincing” evidence of risk from asbestos in drinking water, and the reason why no maximum contaminant levels have been set. However, the agency did tell W5 that it would “continue reviewing ‘new and emerging scientific data’ and if necessary, would consider setting limits to asbestos in water.”
The U.S. Environmental Protection Agency has a maximum contaminant level of 7 million fibres per litre for drinking water. The EPA states those who consume water with higher than that amount over extended periods may face an increased risk of developing benign intestinal polyps.
The World Health Organization’s position is that any asbestos in drinking water is mostly eliminated by the body through feces. However, the European Union has indicated that A-C pipes should no longer be used for drinking water.
The W5 episode focuses heavily on the City of Regina, where officials say the community has about 530 km of A-C water mains. City workers replace about 10 km of pipes per year that have a high break rate. W5 reported that they had water tested from a location near a Regina water main break. Their tests revealed 370,000 asbestos fibres per litre in Regina, though the composition of the pipe itself was unclear.
In response, the City of Regina has stated that no asbestos has been found in drinking water during testing.
The W5 episode (available here) also contracted analysis of drinking water from six Winnipeg neighbourhoods to see if asbestos was present. Some samples showed 60,000 fibres per litre.
