Bushfires are currently burning in Australian states including Victoria, Tasmania, Western Australia and South Australia. In some areas, fire authorities have warned residents about the presence of smoke.

Bushfire smoke is harmful to our health. Tiny particles of ash can lodge deep in the lungs.

Exposure to this type of smoke may worsen existing conditions such as asthma, and induce a range of health effects from irritation of the eyes, nose and throat to changes in the cardiovascular system.

Public health recommendations during smoke events tend to provide general advice, and don’t often include advice specifically geared at children. But children are not just little adults. They are uniquely vulnerable to environmental hazards such as bushfire smoke for a number of reasons.

Different physiology, different behaviour

Children’s lungs are still developing and maturing.

Airways are smaller in children, especially young children, which is associated with greater rates of particle deposition – when particles settle on the surfaces of the airways.

Children also breathe more air per kilogram of body weight compared with adults, and therefore inhale more polluted air relative to their size.

Further, children’s detoxification systems are still developing, so environmental toxins take longer to effectively clear from their bodies.

Meanwhile, children’s behaviour and habits may expose them to more environmental toxins than adults. For example, they tend to do more physical activity and spend more time outdoors. Higher levels of physical activity lead to more air inhaled per kilogram of body weight.

Also, a normal and important part of children’s early play is exploring their environment, including by putting things in their mouth. This can result in kids ingesting soil, dust and dirt, which often contain environmental contaminants.

For these reasons, it’s important to consider the specific needs of children when providing advice on what to do when there’s smoke in the air.

Keeping our environments healthy

The Australian government offers recommendations for minimising the health risks from exposure to bushfire smoke. The main advice includes staying indoors and keeping doors and windows closed.

This is great advice when the smoke is thick outside, but air pollutants may still accumulate inside the home. So it’s important to air your home once the smoke outside starts to clear. Take advantage of wind changes to open up and get air moving out of the house with a cross breeze.

Kids are natural scientists, so get them involved. For example, you and your child can “rate” the air each hour by looking at a landmark outside your home and rating how clearly you can see it. When you notice the haze is reducing, open up the house and clear the air.

Because air pollutants settle onto surfaces in our home and into household dust, an easy way to protect kids during smoky periods is to do a daily dust with a wet cloth and vacuum regularly. This will remove pollutants and reduce ingestion by children as they play. Frequent hand washing helps too.

Healthy bodies and minds

Research exploring the effects of bushfire smoke exposure on children’s health is sparse. However, during smoke events, we do see an increase in hospital visits for asthma, as well as children reporting irritation to their eyes, nose and throat.

If your child has asthma or another medical condition, ensure they take any prescribed medications on a regular schedule to keep their condition well controlled. This will minimise the risk of a sudden worsening of their symptoms with bushfire smoke exposure.

Make sure any action plans for symptom flare-ups are up to date, and ensure you have an adequate supply of in-date medication somewhere easy to locate and access.

Kids can get worried during bushfires, and fire emergencies have been linked with a reduction in children’s mental health. Stories such as the Birdie’s Tree books can help children understand these events do pass and people help one another in times of difficulty.

Learning more about air pollution can help too. Our group has a children’s story explaining how air pollution affects our bodies and what can help.

It’s also important for parents and caregivers not to get too stressed, as children cope better when their parents manage their own anxiety and help their children do the same. Try to strike a balance between being vigilant and staying calm.

What about masks?

N95 masks can protect the wearer from fine particles in bushfire smoke, but their use is a bit complicated when it comes to kids. Most young children won’t be able to fit properly into an N95 mask, or won’t tolerate the tight fit for long periods. Also, their smaller airways make it harder for young children to breathe through a mask.

If you choose to use an N95 mask for your children, it’s best to save them for instances when high-level outdoor exposure is unavoidable, such as if you’re going outside when the smoke is very thick.

N95 masks should be replaced after around four hours or when they become damp.

If your child has an existing heart or lung condition, consult their doctor before having them wear an N95 mask.

Our team is currently recruiting for a study exploring the effects of bushfire smoke in children. If you live in south east Queensland and are interested in participating in the event of a bushfire or hazard reduction burn near your home, please express your interest here.

Dwan Vilcins, Group leader, Environmental Epidemiology, Children’s Health Environment Program, The University of Queensland; Nicholas Osborne, Associate Professor, School of Public Health, The University of Queensland, and Paul D. Robinson, Conjoint Professor in Respiratory and Sleep Medicine, Child Health Research Centre, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Most of us are fortunate that, when we turn on the tap, clean, safe and high-quality water comes out.

But a senate inquiry into the presence of PFAS or “forever chemicals” is putting the safety of our drinking water back in the spotlight.

Lidia Thorpe, the independent senator leading the inquiry, says Elders in the Aboriginal community of Wreck Bay in New South Wales are “buying bottled water out of their aged care packages” due to concerns about the health impacts of PFAS in their drinking water.

So, how is water deemed safe to drink in Australia? And why does water quality differ in some areas?

Here’s what happens between a water catchment and your tap.

Human intervention in the water cycle

There is no “new” water on Earth. The water we drink can be up to 4.5 billion years old and is continuously recycled through the hydrological cycle. This transfers water from the ground to the atmosphere through evaporation and back again (for example, through rain).

Humans interfere with this natural cycle by trapping and redirecting water from various sources to use. A lot happens before it reaches your home.

The quality of the water when you turn on the tap depends on a range of factors, including the local geology, what kind of activities happen in catchment areas, and the different treatments used to process it.

How do we decide what’s safe?

The Australian Drinking Water Guidelines define what is considered safe, good-quality drinking water.

The guidelines set acceptable water quality values for more than 250 physical, chemical and bacterial contaminants. They take into account any potential health impact of drinking the contaminant over a lifetime as well as aesthetics – the taste and colour of the water.

The guidelines are not mandatory but provide the basis for determining if the quality of water to be supplied to consumers in all parts of Australia is safe to drink. The guidelines undergo rolling revision to ensure they represent the latest scientific evidence.

From water catchment to tap

Australians’ drinking water mainly comes from natural catchments. Sources include surface water, groundwater and seawater (via desalination).

Public access to these areas is typically limited to preserve optimal water quality.

Filtration and purification of water occurs naturally in catchments as it passes through soil, sediments, rocks and vegetation.

But catchment water is subject to further treatment via standard processes that typically focus on:

• removing particulates (for example, soil and sediment)
• filtration (to remove particles and their contaminants)
• disinfection (for example, using chlorine and chloramine to kill bacteria and viruses)
• adding fluoride to prevent tooth decay
• adjusting pH to balance the chemistry of the water and to aid filtration.

This water is delivered to our taps via a reticulated system – a network of underground reservoirs, pipes, pumps and fittings.

In areas where there is no reticulated system, drinking water can also be sourced from rainwater tanks. This means the quality of drinking water can vary.

Sources of contamination can come from roof catchments feeding rainwater tanks as well from the tap due to lead in plumbing fittings and materials.

So, does all water meet these standards?

Some rural and remote areas, especially First Nations communities, rely on poor-quality surface water and groundwater for their drinking water.

Rural and regional water can exceed recommended guidelines for salt, microbial contaminants and trace elements, such as lead, manganese and arsenic.

The federal government and other agencies are trying to address this.

There are many impacts of poor regional water quality. These include its implication in elevated rates of tooth decay in First Nations people. This occurs when access to chilled, sugary drinks is cheaper and easier than access to good quality water.

What about PFAS?

There is also renewed concern about the presence of PFAS or “forever” chemicals in drinking water.

Recent research examining the toxicity of PFAS chemicals along with their presence in some drinking water catchments in Australia and overseas has prompted a recent assessment of water source contamination.

A review by the National Health and Medical Research Council (NHMRC) proposed lowering the limits for four PFAS chemicals in drinking water: PFOA, PFOS, PFHxS and PFBS.

The review used publicly available data and found most drinking water supplies are currently below the proposed new guideline values for PFAS.

However, “hotspots” of PFAS remain where drinking water catchments or other sources (for example, groundwater) have been impacted by activities where PFAS has been used in industrial applications. And some communities have voiced concerns about an association between elevated PFAS levels in their communities and cancer clusters.

While some PFAS has been identified as carcinogenic, it’s not certain that PFAS causes cancer. The link is still being debated.

Importantly, assessment of exposure levels from all sources in the population shows PFAS levels are falling meaning any exposure risk has also reduced over time.

How about removing PFAS from water?

Most sources of drinking water are not associated with industrial contaminants like PFAS. So water sources are generally not subject to expensive treatment processes, like reverse osmosis, that can remove most waterborne pollutants, including PFAS. These treatments are energy-intensive and expensive and based on recent water quality assessments by the NHMRC will not be needed.

While contaminants are everywhere, it is the dose that makes the poison. Ultra-low concentrations of chemicals including PFAS, while not desirable, may not be harmful and total removal is not warranted.

Mark Patrick Taylor, Chief Environmental Scientist, EPA Victoria; Honorary Professor, School of Natural Sciences, Macquarie University; Antti Mikkonen, Principal Health Risk Advisor – Chemicals, EPA Victoria, and PhD graduate, School of Pharmacy and Medical Sciences, University of South Australia, and Minna Saaristo, Research Affiliate in the School of Biological Sciences, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.