Asbestos in drinking water

Asbestos is a term for a group of naturally occurring fibrous minerals that have been used in a wide range of cement-based building products including roofing, wall and fence sheeting, water pipes, and flues to heating appliances. (In WA, AC products were manufactured between 1921 and 1987. The use of most asbestos products was phased out during the 1980s, and manufacturing of all asbestos products ceased in 1987.) 

Asbestos fibres pose a serious risk to your health when breathed in, and care should be taken when handling any building material that could potentially contain asbestos. Asbestos fibres when swallowed, however, have not been shown to be harmful. Therefore, asbestos fibres that may be present in drinking water are not considered to be hazardous to human health. 

This factsheet has been created by the Department of Health (DOH) to provide answers to the following questions regarding asbestos in drinking-water:
  • How does asbestos get into drinking-water?
  • Should I be concerned about asbestos in my drinking-water?
  • Are there any guidelines concerning asbestos in drinking-water?
  • Are asbestos levels in scheme drinking-water supplies monitored?
  • Are there any other issues I should consider about asbestos in water?
  • How can I find out if my roof or water pipes are made of asbestos?

How does asbestos get into drinking-water?

Asbestos in drinking-water can come from a variety of different sources including asbestos-containing minerals, industrial waste, and asbestos roofing and pipes. Rainwater collected from roofs containing asbestos cement (AC), for example, may contain asbestos. Similarly, any AC pipes used in a water distribution system may degrade over time, allowing asbestos material to enter drinking-water.

Should I be concerned about asbestos in my drinking-water?

No. While studies have clearly shown that asbestos poses a serious health risk when it is dry and inhaled, there is very little evidence to show that asbestos fibres will cause any harm when they are wet and swallowed.

The effects of asbestos in the water supply have been studied extensively, and results have not shown an elevated risk of asbestos-related disease. In addition, although inhaled asbestos is a known carcinogen (cancer-causing substance), asbestos when swallowed is considered to pose very little, if any, carcinogenic risk to human health. 

Similarly, any inhalation of aerosols associated with showering or irrigation are unlikely to present a risk from asbestos in the water.

Are there any guidelines concerning asbestos in drinking-water?

Yes. The 2004 Australian Drinking Water Guidelines (2004 ADWG), as published by the National Health and Medical Research Council (NHMRC), provide a factsheet on asbestos in drinking-water. The fact sheet states “There is insufficient data to set a guideline value”, “as the weight of evidence indicates that ingested asbestos is not hazardous to health”. Also the World Health Organization (WHO) has concluded that establishing a guideline for asbestos in drinking-water is unnecessary, given the absence of evidence that the ingested asbestos is hazardous to health.

Are asbestos levels in scheme drinking-water supplies monitored?

No. Australian scheme supplies are not routinely monitored for asbestos because asbestos fibres in drinking-water are not considered harmful to human health.

Are there any other issues I should consider about asbestos in water?

Yes. As AC roof structures deteriorate over time, asbestos fibres will be released and can either be washed into a rainwater tank or soak well. Care should be taken to ensure that if you have to desludge a rainwater tank the sludge is kept wet at all times while it is being removed and disposed. Similarly any maintenance to soak wells should only be done when the soil is wet to prevent the release of any dust.

How can I find out if my roof contains asbestos?

It is difficult to determine if a roof material contains asbestos by simply looking at it. If you do not know if a material contains asbestos, remain cautious and treat it as though it does. To be certain, you can have the material tested at a laboratory accredited by the National Association of Testing Authorities (NATA). Testing laboratories can be found by contacting NATA Inspection and Testing Services, Bentley (08) 9489 2800.

Summary

  • Asbestos in drinking-water may come from a variety of sources including asbestos-cement water pipes and roofing material.
  • Asbestos fibres that may be found in drinking water are not considered to be hazardous to human health.
  • The 2004 Australian Drinking Water Guidelines and World Health Organisation have not set a guideline value for asbestos due to the absence of evidence that asbestos is hazardous to health.
  • Rainwater tank sludge from AC roofs should be kept wet at all times while being removed and disposed.
  • Any maintenance to rainwater soak wells from AC roofs should only be done when the soil is wet to prevent the release of any dust.
  • Building materials manufactured after 1987 are unlikely to contain asbestos however if you are unsure have it tested by a NATA accredited laboratory. 

More information

Water Unit, Environmental Health Directorate
Department of Health
Telephone: 9388 4999
Last reviewed: 22-06-2016
Produced by

Public Health