We are what we breathe

If you replace the contents of a five-gallon bottle that sits aloft a water cooler, substituting water with air, you will breathe an equivalent of 600 bottles every day, taking approximately 20,000 breaths.

It is generally an unconscious action whereby air that passes through our nose and mouth and into our lungs. The air consists of oxygen (21 per cent) with nitrogen (78 per cent), and the remaining is small amounts of argon, carbon dioxide and other gases and water vapour (one per cent).

Individually and collectively, we take the air we breathe for granted and yet every breath is vital for sustaining our lives, supplying our blood with oxygen and removing metabolic waste in the form of carbon dioxide.

A 2004 research paper concluded that mothers who used air fresheners daily suffered almost 10 per cent more headaches than those who used them less than once a week. Photograph: iStock

Within the air, dusts, chemical components and biological agents will be present; these variables can affect our health, both physiologically and psychologically, they can affect our perception of our environment, determining whether our surroundings are conducive and comfortable.

Our noses are the gatekeepers to our lungs, they tell us that the air is different in a bakery, sewer, restaurant or farm. Distinctive odours all carry molecules; tiny amounts can trigger our olfactory receptors and our emotions to the odour.

Our noses warn us of dangerous environments that may be polluted; however, some dangers are odourless, such as carbon monoxide or indeed substances such as synthetic scents which possess a pleasant smell and may skew our reaction to the potential harm.

As most individuals spend approximately 90 per cent of their time indoors, they are therefore exposed to the indoor environment to a much greater extent than the outdoors.

Indoor pollutants can be generated from mould, volatile organic compounds (VOCs) from furnishings and building materials, chemical fumes from cleaning products, paints, combustion gases, radon, dust mites, animal hair and dander. Aside from the indoor pollutant sources, external air becomes concentrated as it filtrates into our indoor environments and adds to the toxic soup.

With hundreds of varied compounds, typical immediate health effects can include eye, nose and throat irritation, headaches, migraines, nausea, fatigue and feelings of dizziness. Such immediate effects are usually short-term and treatable. Sometimes the treatment is simply eliminating the person’s exposure to the source of the pollution – if it can be identified.

Reaction to indoor air pollutants can be individually determined by factors such as gender, age, activity within the exposed area, individual sensitivity, repetitive exposure and/or pre-existing conditions.

Julie Riggs: " Mental health conditions, reduction in productivity and comfort have also been linked to changes in air quality."

Other health effects may show up years after exposure has occurred or only after long or repeated periods of exposure. These effects, which include respiratory diseases, heart disorders and cancer, can be severely debilitating or fatal. Mental health conditions, reduction in productivity and comfort have also been linked to changes in air quality.

Reduced cognitive function

As we breathe air into our lungs, a gas exchange occurs between our blood and the air. The lungs contain five lobes filled with small spongy sacs called alveoli. The alveoli walls are extremely thin (about 0.2 micrometres) and covered in tiny blood vessels called pulmonary capillaries.

As we breathe in, oxygen diffuses into the red blood cells and releases back used carbon dioxide, which we exhale (approximately 4–5 per cent). The oxygen travels initially to the heart, and then is pumped around the rest of our body. But is it not just oxygen that diffuses into our blood.

Because many particulates of pollution are so small, they accompany the oxygen and are also spread around our body, with our blood being the vehicle. These pollutants can travel to other organs, such as our liver, kidneys, spleen, bone marrow and reproductive system. But they can also cross from the brain’s blood vessels into the brain tissue and cause inflammation. It takes four seconds for the air you breathe to impact your brain.

Air pollution impacts start before we are even born. Black carbon particles, emitted by the incomplete combustion of fossil fuels, such as diesel engines and wood burning stoves, have been found in the lungs and brains of foetuses. Children are more vulnerable to exposure due to the fact their organs, immune and neurological systems still developing.

90 per cent of brain development happens by the age of four. Because of their lower body weight, children breathe in a relatively greater volume of air than adults, thus resulting in a greater body burden.

There are numerous studies linking the relationship between babies’ and children’s exposure to fine particulate matter pollution and poorer behavioural functioning, low IQ, low memory and cognitive performance.

Good indoor air quality programmes are increasingly embedded into corporate wellbeing strategies to deliver a healthier and happier work environment. Photograph: iStock

Polycyclic aromatic hydrocarbons, which are a by-product of fossil fuel combustion, are linked to exposure in children who experience attention problems and anxiety and depression symptoms.

But it is not just children. Increasing amounts of evidence are emerging that show airborne pollutants are associated with an increased risk of dementia, Alzheimer’s disease and general cognitive decline in older adults. Researchers in Canada looked at 6.6 million people, using their postcodes to measure how close they lived to major roads and their medical records to identify residents who had gone on to develop dementia.

The Lancet in 2020 listed air pollution as one of 12 important ‘modifiable’ risk factors for dementia. Of course, there are many contributing factors that can influence dementia risk, including genetics, health condition and age.

As often is the case, health factors can be latent and it can be difficult to conclusively state a major contributing cause. So researchers have been looking at ‘oxidative stress’ which is the imbalance of toxic molecules inside our cells and the antioxidants we need to remove them. This has itself been connected to the onset of dementia.

Air pollutants can cause restricted blood-flow in arteries, which can lead to higher blood pressure and an increased risk of stroke, both risk factors for dementia. Higher rates of psychiatric illnesses, such as depression, schizophrenia, bipolar disorder and personality disorders, have all been linked to polluted air.

Lack of oxygen, substance asphyxiation or a compound that reduces oxygen can affect brain tissue. Heavy metals and mixed organic solvents have been associated with brain disorders, including mood changes, motor function problems and mental slowing, and memory and concentration problems. Cheshire-born Lewis Carroll, who wrote Alice’s Adventures in Wonderland in 1865, would have resided near the local hat factories and potentially witnessed the effects of mercury on the central nervous system of employees, perhaps providing inspiration for the novel’s Mad Hatter character.

Can good air quality help chess players?

Let’s consider a common gas that surrounds us, we even contribute towards the pollutant. Carbon dioxide (CO2), the air we exhale. Typical indoor concentrations can range from 380ppm – 2500ppm.

The Workplace Exposure Limits EH40/2005 supplement to the Control of Substances Hazardous to Health Regulations 2002 enforces a maximum of 5,000 ppm long term exposure (an employee’s average airborne exposure in any 8-hour work shift of a 40-hour work week to protect against undesirable changes in the acid–base balance of the body. Although CO2 workplace exposure limits are not exceeded, lower concentrates of 1,000ppm have be shown to affect the body physically and psychologically.

It is difficult to provide a direct cause of health effects associated with indoor air quality, but collective research has indicated that carbon dioxide exceeding 800ppm will result in a range of health and comfort factors. These include headache, fatigue, eye symptoms, nasal symptoms and respiratory tract symptoms. Carbon dioxide can affect individuals with sensitivities to changes in air quality and can contribute towards some conditions such as migraines.

Even mental health conditions, such as stress, anxiety and depression, have significant contributing factors. 16 years ago I conducted a study looking at slight elevations of CO2 in students performing reactional, performance tasks. Levels reaching 1,000ppm resulted in a 30 per cent reduction in cognitive ability (reaction, decision making).

This study has been replicated since by different researchers with similar results. We do not often associate air quality with poor productivity – however consider how a 30 per cent reduction could be critical in certain occupations, such as an airline pilot. Or when you need to make a strategic decision, such as a chess move. With the prize money of US$1.6m for the Champions Chess Tour, a slight reduction in strategic thinking could be the difference between first and second place.

Researchers have investigated how indoor air quality affects the quality of strategic decision-making based on data from official chess tournaments. They analysed a unique data set linking the readings of air-quality monitors (CO2, particulate matter and temperature °C) inside the tournament room against the quality of 30,000 moves by 121 players across three tournaments in Germany in 2017, 2018, and 2019, each of which lasted two months.

The researchers then compared the moves against the optimal ones determined by a chess computer and found that even with a slight increase in air pollution, the likelihood that players would make a mistake increased by 2.1 per cent and the severity of the errors rose by 10.8 per cent.

Similar studies have looked at high strategic decision making, including the New York Stock exchange in the US and 100,000 investors in a German brokerage firm. Particle pollution was analysed against the decisions of investment, with one standard deviation was associated with an 11.9 per cent reduction in same-day returns.

The secrets of scents

Scented candles and other scented products are on the increase. You only need to look at the supermarket aisle of air fresheners to see a growing industry. Scent is more closely linked to our memories than other senses, hence these ‘emotional’ scents can stimulate our brains.

95 per cent of the chemicals used in fragrances today are synthetic compounds derived from petroleum, including benzene derivatives, aldehydes, and many other known toxins and sensitisers, which are known toxins capable of causing allergic respiratory disorders (asthma), as well as neurological and cutaneous disorders. 84 per cent of these ingredients have never been tested for human toxicity, or have been tested only minimally. Many of the chemicals are nerve toxins with recognised effects on the central nervous system.

95 per cent of the chemicals used in fragrances today are synthetic compounds derived from petroleum, including benzene derivatives, aldehydes, and many other known toxins. Photograph: iStock

Studies have shown that inhaling fragrances can also cause circulatory changes and electrical activity in the brain. These changes can trigger migraine headaches; affect the ability to concentrate and cause dizziness and fatigue.

Research suggests that perfumed products may contribute towards Attention deficit hyperactivity disorder (ADHD); and the use of the plasticisers phthalates diethyl phthalate (DEP) or di-methyl phthalate (DMP) has been associated with numerous impacts on male reproductive health, including changes in hormone levels and genital development in baby boys.

Aluminium in aerosol form may be more readily absorbed into the brain through the nasal passages. Studies show that regular use of these products, in particular deodorant aerosols, can increase the risk of Alzheimer’s by as much as three times.

A 2004 research paper concluded that mothers who used air fresheners daily suffered almost 10 per cent more headaches than those who used them less than once a week. And that of the mothers who used air fresheners, 16 per cent suffered from depression compared with 12.7 per cent of those mothers who hardly ever used air fresheners. A third of all the fragrance chemicals currently in use have been flagged as potentially toxic by scientists around the world.

Ingredients like formaldehyde, phthalates, parabens, and toluene – known as polyfluoroalkyl substances (PFAS) – that have been established in scientific literature as causing or likely causing cancer, birth defects, hormone disruption, infertility and more, are legally allowed in these products.

Some of these chemicals can stay stored in our blood and fatty tissue forever. It is estimated that on average, a body burden (the amount of a particular chemical stored in the body at a particular time), is approximately 700 contaminants. There has been a heightened discussion around PFAS recently, otherwise known as “forever chemicals” because they are so persistent.

Fragrance formulas are considered trade secrets; manufacturers only have to state fragrance on the label and do not need to identify the chemical make-up. Fragrance-free or unscented does not guarantee they do not contain fragrance chemicals: they imply they have no perceptible odour.

An emerging issue of brain health

Indoor air quality is often seen as an invisible hazard and when discussed, we associate the discussion with our environment and physical health. But, without doubt, the ability to breath clean, unpolluted air to protect our brain function has huge emotional, economic and moral reasoning. 99 per cent of the global population breathes unclean air that does not meet the World Health Organization guidelines. In urban areas where pollution is high, brain health inequality is forming.

Some businesses are starting to engage more in the indoor air quality debate, and are raising awareness through training, introducing policies, adopting the topic into their employee wellbeing programmes, discussing the concerns with their HVAC/facility engineers and OHS practitioners. Some forward-thinking organisations are even displaying QR codes in their building so people can be informed about the air quality. The owners at Apricot Tree Café in Mississauga, Ontario, Canada, is an example.

Good indoor air quality (IAQ) programmes are essential for the ‘lungs of a building’ to be ‘well’. IAQ is increasingly embedded into corporate wellbeing strategies to deliver a healthier and happier work environment. If you expect the food you eat and the water you drink to be uncontaminated, you should also expect the air we breathe to be safe.

We therefore need to adopt upstream health interventions, identifying the sources of pollution and protecting against long-term ill health and discomfort.

As a society, we need to take the conversation about air quality more seriously, and further investment in research is needed. It is time for researchers to develop the evidence that will allow governments, businesses and individuals to demand global standards for indoor air quality, to reduce emissions, exposure and harm and achieve a fundamental right to breathe clean air.

Dr Julie Riggs will be speaking on ‘The impact of indoor air quality on occupants’ cognitive function, productivity and wellbeing’ at the BSC’s Wellbeing Conference on 18 April. Book at: britsafe.org/wellbeing2023

Dr Julie Riggs is senior head of education at the British Safety Council