Asbestos in Drinking Water: Evaluating Risks, Testing, and Remediation
You drink water, knowing it’s healthy for you. But could our water supply eventually contribute to ill health? If we continue to drink water moving through degrading asbestos pipes, that might be the outcome in the future.
Asbestos isn’t just in our homes. It’s also in our infrastructure we rely on for fresh, clean drinking water every day. Learn more about the risks, testing, and remediation of asbestos in drinking water below.
Why Is There Asbestos In Our Water?
Technically, the fresh and clean drinking water we obtain from our dams, aquifers, and rivers doesn’t contain asbestos. However, it can become contaminated with asbestos if it’s directed through concrete pipes that contain asbestos.
We replaced our aging pipes with asbestos-containing pipes until the 1980s, with no new ones installed since 1986. However, many of those old asbestos pipes are still in use and no longer in excellent condition.
As the pipes get older, asbestos fibres can start being released into the drinking water. It’s also possible for asbestos to get into our water supplies from construction sites and landfills.
The situation is particularly dire in Christchurch. According to a study on asbestos’s concentration and prevalence in Christchurch’s drinking supply, 19 of 20 samples from mains water supplies via hydrants showed long and short asbestos fibres. Samples were collected from pipes installed from the 1930s to the 1960s, with ‘abundant evidence’ of fibres being released from pipes of this age.
The study concluded by saying that we should prioritise the replacement of pipes 50+ years old to reduce the risk of water-carried asbestos into urban environments. The goal would also be to reduce the risk of asbestos ingestion from contaminated water sources.
What Are the Risks of Asbestos In Water?
We know that asbestos fibres are harmful to breathe in. When those tiny fibres embed in our lungs, we can be at risk of cancer, mesothelioma, and other uncomfortable and deadly illnesses. Hundreds of Kiwis die from such illnesses each year. However, there isn’t a great deal of information and knowledge surrounding the dangers of asbestos in water.
Currently, there is no consistent evidence to suggest that drinking asbestos increases the cancer risk. However, drinking asbestos daily for extended periods may be harmful to our health.
Some troubling information has also come to light in recent years, highlighted by the CDC. Some research suggests that people who have been exposed to asbestos fibres in water have a higher-than-average death rate from intestinal, stomach, and oesophagus-related cancers. At this stage, we don’t know whether this is related to asbestos or something else. In animal studies, instances of fatal cancers weren’t more pronounced. However, some rats did get more non-fatal tumors in some studies.
Testing for Asbestos in Water
The average person might test for asbestos in their homes before undertaking renovations. However, they likely aren’t testing for asbestos in their water supply. Fortunately, sample collectors do this for us.
In the previously mentioned Christchurch study, sample collectors obtained samples from hydrants and taps along the pipe network. They collected the water in 500mL plastic low-density polyethylene bottles. These bottles had been acid-washed and twice rinsed with purified water before the samples were collected.
Once the samples were obtained, experts used a YSI multi-sensory probe to record their temperature, electrical conductance, and pH before they were cooled to four degrees Celsius. They were then sent to a lab for pre-treatment with ozone gas and UV light before being analysed with transmission electron microscopy. After this whole process, it was revealed that Christchurch residents were drinking water with >10 μm and 0.5 μ asbestos fibres.
How to Get Asbestos Out of Our Drinking Water
Once asbestos is in drinking water, it can be practically impossible for homeowners to get it out of there. The most effective option is removing it at the source: the pipes.
That takes time. As of 2022, New Zealand has 9,000 kilometres of asbestos pipes that need to be replaced at approximately $2.2 billion. Currently, the oldest pipes are 20 to 30 years overdue for replacement, with asbestos older than 50 years at the highest risk of degradation.
Fortunately, many councils already have plans in place to replace aging pipes. For example, the New Plymouth District Council planned to invest $280 million in its water network over the next ten years. Much of that plan involved replacing pipes containing asbestos cement.
Learn More About Asbestos Today
Knowledge is power. The more we know about this hazardous material, the more steps we can put in place to keep ourselves safe. At a government and council level, this involves performing research into the presence of asbestos in our water supplies and replacing asbestos cement pipes. With time and investment, asbestos in our water can be a problem of the past.