- Many water supplies across Australia come from groundwater, where nitrate can naturally occur.
- In most occasions nitrate poses no harmful risk to your health however, pregnant women and infants should take extra care.
Reasons you might find nitrate in water
Water supplies throughout Australia often come from groundwater, which naturally contains a variety of chemical compounds, amongst which can be nitrate. Most commonly nitrates may be found where the region local to the groundwater has had significant plant decay underground. Nitrates are created as a part of the decaying process, and are able to move relatively quickly and easily through soil, owing to how soluble they are. Alternatively groundwater cane become contaminated with higher levels of nitrates through animal waste run-off from dairies and feedlots, excessive use of fertilizers, or seepage of human sewage from private septic systems.
Nitrate and your health
It’s generally accepted that low levels of nitrates typically pose little threat to the majority of adults; however pregnant women, infants and those with a G6PD deficiency should take special care as to the monitoring of their water supplies.
The Nitrate in drinking water supplies within water is 50mg per litre for children up to three months of age; whilst this is set at 100mg per litre past this age. The distinction between children up to three months is due to the potential risk of 'blue baby' (Methaemoglobinaemia) syndrome where decreased oxygen to the brain is experienced and is a condition that has been linked with high levels of Nitrate consumption. This has been a particular course for concern among many indigenous communities in Western Australia where they have experienced severe side affects.
At significantly high levels of consumption Methaemoglobinaemia can also occur in adults. The official Australian Drinking Water Guidelines provide clear advice for supplies that are over and above 100 mg per litre:
“Drinking [Water with nitrate concentration above 100 mg per litre] not recommended for any age. Treat water or seek alternative water supplies. If necessary seek Health Department advice”.
Advice on how to remove nitrate from your tap water
Whilst you can’t see, smell or taste nitrate, the growth of bacteria that can occur where there are excessive levels of nitrate may affect the odour or taste. If you're experiencing unexpected headaches and fatigue these can be symptoms linked to high levels of nitrate in your water.
Nitrate can be removed from water using a variety of processes, including: ion exchange and reverse osmosis. It’s important to note that heating or boiling nitrate contaminated water will have little effect and can actually even increase the concentration.
Who to contact if you find nitrates in tap water
For questions about nitrate levels in your drinking water, get in touch with the following organisations relevant to your location:
The Western Australian Health Department can be contacted on 08 9388 4999.
Northern Australia is a territory with a wide array of public bodies that serve individual regions; visit the Department of Health for the Northern Territory Government website to find out more.
For contact details for The Queensland Government Department of Energy and Water Supply, follow this link.
South Australia is committed to monitoring the standards of their water suppliers - more information about this can be found in their 2013-2014 Drinking Water Quality Report. South Australia’s water entities are publicly owned and known as the business entity SA Water, you can contact them via the SA Water contact page.
South Wales adopt a robust approach to the monitoring of all water chemicals, more information on this can be found on the NSW Drinking Water Monitoring Program; you may also contact the NSW Ministry of Health via their contact page or read their Private Water Supply Guidelines.
Victoria has recently revised their Safe Drinking Water Regulations – you can read more about this here. Victoria also undertake an annual report of the water quality throughout the state, download the 2014-2015 report here.
Should you have concerns about your water supply in Victoria, you can contact the government’s dedicated department for their water program on: 1300 761 874 (during business hours); on pager: 1300 790 733 (which is a 24-hour pager service for public health emergencies) or by email: water[at]dhhs.vic.gov.au.