The water coming out of your tap may look clear, but there is a lot more to it than meets the eye. When it comes to chemicals in tap water Australia has much more relaxed standards than a lot of other countries. Our water infrastructure and supply systems face significant challenges, and compromises have been made in the name of protecting people from the most serious threats.
However, these compromises mean that many Australians are being exposed to higher levels of chemicals from their tap water than they realise. From chlorine levels higher than the recommended dosage for a public swimming pool to heavy metals from ageing pipes and industrial pollution, tap water chemicals are a serious matter for millions of people.
The Australian Drinking Water Guidelines (ADWG) set out rules for which chemicals should be added to Australian tap water, as well as recommended limits for other chemicals and contaminants that may enter our water supply. This article answers some common questions about Australian tap water chemicals, including what you can do to make sure you are drinking, bathing, and washing with the best water possible.
Where do tap water chemicals come from?
Chemicals can enter Australian tap water in three ways: they can be present in the original water source, they can be added during the water treatment process, or they can enter the water as it travels from the treatment plant to your home.
The water coming out of your tap will be strongly influenced by the environment from which it was originally drawn. Rainwater reservoirs, for example, may have significantly lower calcium and magnesium levels than underground aquifers but will be more vulnerable to airborne particles like pesticides and heavy metal dust.
Most source-drawn impurities in Australian water are either naturally occurring particles (e.g. calcium, algae, sediment, etc.) or pollutants from industrial run-off. Water treatment processes help control harmful contaminants like bacteria and dangerous toxins, but not all environmental impurities can be removed before the water reaches your home.
Some chemicals are deliberately added to tap water during the treatment process. Most treatment chemicals are disinfectants, added to neutralise harmful bacteria and keep the water sterile on its way to your tap. Other treatments include coagulants, which make contaminants easier to remove, and chemicals like fluoride, which is added in accordance with government policies to address dental health.
Chemicals that enter the water after the treatment process are typically either metal particles picked up from ageing pipes or disinfection by-products that are produced when disinfectants react with organic matter in the water. These impurities bypass the large-scale water treatment process, so households must use individual water filtration systems to remove them.
Is there chlorine in tap water in Australia?
Chlorine is the most commonly used disinfectant for water treatment in the world. Popular for its low cost and ease of use, chlorine has been widely used in municipal water disinfection for over a century.
In Australia, chlorine is used to neutralise bacteria and waterborne pathogens as mains water travels to our homes. Chlorine dissipates over time, so water utilities have to use strong enough doses to make sure disinfectants are present to keep the water bacterially safe all the way to your tap.
However, the trade-off of this thoroughness is that your tap water will often have quite high levels of chlorine in it, especially if you live in a city or near a water treatment facility. The ADWG allows for chlorine concentrations up to 5mg/L. While this level of chlorine is not toxic in drinking water, it does have a powerful effect on its taste and smell; the threshold for detecting the flavour and odour of chlorine is typically around 0.3mg/L.
What chemicals are in tap water because of water utilities?
Water utilities in Australia add chemicals to town water supplies for a number of reasons, from disinfection to improving overall public health. The exact chemicals present in your water will vary depending on the treatment processes used in your region, and their levels will vary depending on your proximity to the treatment plant.
Chlorine
As discussed above, chlorine is the most commonly used disinfectant chemical for water treatment. It kills bacteria and is not typically toxic at the levels found in Australian tap water. However, even safe levels of chlorine can cause irritations to your skin, eyes, and lungs. Long-term chlorine exposure can also have more serious health effects; the risk of developing certain cancers increases significantly when comparing data on people who drink chlorinated tap water compared to water without chlorine.
Ammonia & Chloramine
Chlorine dissipates over time, so it is not always the best option for water treatment and disinfection in a country as large as Australia. Certain regions that need their water to travel long distances without losing bacterial protections add ammonia to the chlorine, forming a more stable compound called chloramine.
Chloramine takes much longer to dissipate, making it both more reliable for disinfection and more difficult to remove through filtration. Removing chloramine requires specialised catalytic carbon filters.
Chlorine dioxide
In addition to liquid chlorine and chloramine treatments, some water utilities use small amounts of chlorine dioxide. This gas is an effective disinfectant, but it can also be highly toxic in larger doses so its use is limited.
Ozone
Ozone is a powerful oxidiser, highly effective for neutralising bacteria and organic contaminants in drinking water. However, it is significantly more expensive than chlorine, is toxic at higher concentrations, and can produce carcinogenic by-products. The ADWG outlines strict standards for its use in public water treatment.
Fluoride
Fluoride has been added to Australian tap water for several decades in line with government initiatives to improve dental health. The fluoride is absorbed into our bodies so that trace amounts are present in our saliva, adding a constant level of basic protection to our teeth.
However, water fluoridation has been a controversial topic ever since it was introduced. There has been a great deal of discussion about the potential health and ethical issues of mass fluoridation, with many Australians preferring to remove fluoride from their water entirely.
Fluoride cannot be removed by most water filters, requiring either very slow gravity filtration or reverse osmosis.
Aluminium
Aluminium sulphate is added to water as a coagulant. Coagulation is a process that makes smaller impurities easier to remove, causing them to clump together so that they can be filtered out during the treatment process.
Excessive, long-term exposure to aluminium has been linked to a number of serious health issues, including neurological disorders and bone diseases.
Is tap water unhealthy without any chemicals?
This long list of chemicals may sound concerning, but tap water with no chemicals at all would pose a much greater risk to public health. Treatment chemicals like chlorine and fluoride may be linked to some serious potential health risks, but they are added to our water for a very good reason.
Untreated water can carry dangerous bacteria, spreading infectious diseases like typhoid, cholera, dysentery, and e coli. High-grade water filters can protect your home from bacteria to a certain degree, but most household filters are designed to process safe, potable water.
There are absolutely valid concerns about the kinds of chemicals that may be present in your tap water and what effects they can have on your body. However, objectively speaking, your water would be a lot unhealthier without them.
Unwanted chemicals in Australian tap water
While treatment chemicals are added deliberately to control water quality, other chemicals may be present either because they are too difficult to remove or because they enter the water supply after the treatment process is complete.
Trihalomethanes
Disinfectants like chlorine and chloramine may be effective for neutralising bacteria, but the chemical reaction that allows them to disinfect public water also produces chemicals like trihalomethanes. Several compounds within this class of chemicals have been classed as carcinogens and endocrine disruptors, increasing your risk of various cancers and developmental/reproductive issues.
Lead
Older homes (built before the 1980s) will often have lead components in their plumbing, either with entire lead pipes or lead soldering between various pipes and fixtures. Lead contamination is now known to be a serious issue, especially for children and pregnant women.
If you live in an older home, consider purchasing a lead testing kit for your tap water and looking into water filtration options that are specifically rated for heavy metal removal.
Copper
While much less toxic than lead, elevated copper levels from abrasion and chemical wear on pipes and plumbing can still be a health risk. Copper is an important mineral our bodies need in small doses, but high levels can lead to issues like stomach cramps, nausea, and diarrhea.
Copper levels vary significantly across Australia depending on the plumbing infrastructure and water sources in your area. Monitoring and controlling copper levels is an important part of keeping your home’s water safe.
Mercury
Like lead, mercury is a heavy metal now known to be highly toxic. While trace amounts of mercury occur naturally in the earth, it often enters public water supplies through industrial pollution and agricultural run-off.
Mercury is one of several substances carefully regulated by the ADWG, but having an activated carbon or reverse osmosis filter in your home is a great way to protect yourself from heavy metals that enter the water stream after the treatment process.
Arsenic
Arsenic is another naturally occurring particle that is highly toxic to humans. It typically enters our water supply when mineral deposits containing the chemical erode and dissolve, or else through groundwater contamination from industrial and agricultural waste.
Nitrates
These chemical compounds made up of nitrogen and oxygen can come from fertilisers, septic systems, and industrial pollution. Proper environmental protections and waste management can help to control nitrate contamination in drinking water, but potentially harmful levels can still enter our water.
High levels of nitrate consumption can cause a condition known as “methemoglobinemia”, a potentially life-threatening condition that impairs your blood’s ability to carry oxygen.
Pesticides
Pesticides, herbicides, and insecticides can travel long distances through dust, aerosolized particles, and even leaching into the water basin. These agricultural products are often highly toxic, with certain chemicals like atrazine found to have an adverse effect on endocrine functions and hormonal balance.
Cadmium, Chromium, Barium, & Sulfates
This group of chemicals occurs naturally in mineral deposits and environments that can contaminate water sources, but their presence is more commonly caused by human activities. Industrial work like mining, smelting, and manufacturing all release contaminants into the environment. This discharge often has a negative effect on aquatic ecosystems, but it is also a concern for drinking water.
Health impacts from these particles range from short-term exposure reactions like skin irritations and respiratory problems to more serious, long-term health issues like cancer and reproductive issues. Water treatment processes are effective for removing most of these particles from town water, but if your home has a rainwater tank then these contaminants can easily collect as dust on your roof and then be washed into your drinking water.
Volatile Organic Compounds
Like trihalomethanes, this is a whole class of disinfection by-product chemicals and compounds that can cause serious health issues. VOCs typically evaporate very easily, entering the air we breathe and being absorbed into our skin.
VOCs can be removed by boiling, but this process just releases them into the air and makes them easier to absorb. Having all the water in your home pass through an activated carbon filter is a great way to make sure your drinking, bathing, and washing water is protected from volatile organic compounds.
Do all homes have the same tap water chemicals?
The exact characteristics of tap water vary significantly across the country. The chemicals in Australian tap water depend on factors like local treatment methods, the age and makeup of water pipes, mineral deposits, local agricultural and industrial activities, and even climate.
Different chemicals break down or flourish in different temperatures and conditions, and treatment methods are more effective in some areas than others. No two homes will have exactly the same water, so it is important to understand what is coming out of your tap in order to ensure you are drinking, washing, and bathing with the best water possible.
Is there PFAS in tap water?
Per- and poly-fluoroalkyl substances (PFAS) have been making headlines for the last few years as we become more aware of their ubiquity and health impacts. Like lead, mercury, and even asbestos, PFAS compounds were a common manufacturing component that we now know are harmful to our health.
Australia has recently made headlines for its PFAS regulations being significantly more relaxed than guidelines elsewhere, with our standards allowing levels 140 times higher than those recommended in America. These so-called “forever chemicals” have been detected in drinking water supplies across Australia, with Sydney’s water utilities recently being called out for having PFAS contamination in town water reservoirs.
While PFAS contamination is most common in groundwater stores where the compounds leach down from industrial waste and chemical firefighting foams, studies in the last few years have found that forever chemicals are also present in rainwater. Regardless of where in Australia you live, it is likely that you will be exposed to some level of PFAS contamination.
How to remove chemicals in tap water
Whether chemicals are naturally occurring, industrial pollutants, added for treatment, or by-products of disinfection, there are plenty of reasons not to want them in your body. Fortunately, there is a simple solution for removing unwanted chemicals and contaminants without sacrificing the benefits of disinfected water: Complete Home Filtration.
Premium whole home water filtration systems protect your home from chemical contamination, heavy metals, hard water damage, and more. Complete Home Filtration is an Australian company that understands the diversity of Australian tap water. This is why they offer individually configured water filters to treat the specific chemicals and contaminants that are in your water, all protected by an Australian-made cover designed to withstand Aussie conditions.
A professional water test is the best way to find out exactly what is in your tap water, and Complete Home Filtration’s water technicians can talk you through the common chemicals and concerns in your area. To find out more and book a FREE water consultation, fill out our contact form below or call us on 1300 693 458.
