It’s not just the planet that is hurting, as Lisa Salmon finds out
What climate change and air pollution are doing to our planet is frightening – but what they can do to our health is equally scary.
The World Health Organisation stresses that air pollution and climate change are intertwined, for example, the shifts in weather patterns due to climate change can cause more ozone to be produced at ground level, which harms our health. Increased ozone levels then contribute to more warming.
“Climate change and air pollution are among the most serious health challenges we face this century,” says BMA board of science chair, Professor Dame Parveen Kumar. “We need to see bold and immediate action if we are to curb this dangerous threat.”
Here the Royal College of Physicians and the Royal College of Paediatrics and Child Health outline 11 of the major health effects, as detailed in their Every Breath We Take: The Lifelong Impact of Air Pollution Report.
1. Premature birth and stillbirth
When pregnant women breathe in some pollutants, these can cross the placenta to the developing baby. Air pollution can affect growth of the unborn baby and may be linked to premature birth, which in some cases can lead to severe disability and early death.
From the earliest stages of development, DNA is susceptible to changes arising from exposure to air pollution.
Evidence also suggests potential links with higher rates of stillbirth. In addition, it is thought the exposure of pregnant women to traffic-related air pollution accounts for more than a fifth of all cases of low birth weight at term.
2. ADHD and low IQ
Children are especially vulnerable to air pollution, and may suffer permanent health impacts from early exposure.
Heavy metals, particularly lead and mercury, which can cross the placenta and accumulate in the foetus, have been associated with neurodevelopmental harm, leading to reduced cognitive function, lower IQ, attention deficit hyperactivity disorder (ADHD), and possibly autism spectrum disorder.
3. Asthma and other childhood respiratory illnesses
There’s “compelling evidence” in children and adults that air pollution exposure is associated with new onset asthma.
In the Californian Children’s Health Study, exposure to higher levels of nitrogen oxides was associated with new-onset asthma and children living within 75m of a major road had a 29% increased risk of lifetime asthma.
Children living in highly polluted areas are four times more likely to have reduced lung function in adulthood. Infants living in areas with high levels of particulate air pollution are at more risk of death in the first year of life.
4. Cardiovascular disease
Studies have shown significant associations between air pollution and a range of cardiovascular problems in adults. Both short- and long-term exposure to air pollution can increase the risk of heart attacks, heart failure, arrhythmias (abnormal heart rhythms) and stroke in at-risk individuals, such as older people or those with pre-existing medical conditions.
The International Agency for Research on Cancer (IARC) classifies outdoor air pollution and particulate matter from it as carcinogenic to humans.
It says there’s strong evidence that exposure to outdoor air pollution is associated with changes in gene expression and genetic damage, which are linked to increased cancer risk. In addition, IARC says there’s “sufficient evidence that exposure to outdoor air pollution causes lung cancer”.
Research suggests some air pollution may be connected to the development of obesity. Prenatal exposure to endocrine-disrupting chemicals, for example, has been reported to increase children’s risk of obesity.
7. Chronic obstructive pulmonary disease (COPD)
There’s strong evidence that long-term exposure to outdoor air pollution suppresses normal lung function growth in children, and accelerates lung function decline in adults. COPD is common in the elderly, and is often linked to smoking. Patients with COPD have a reduced ability to clear inhaled material from their lungs and may, as a result, get a higher-than-normal dose of air pollution.
The Alzheimer’s Society says the most convincing evidence linking air pollution to dementia comes from a 2016 study of 6.6 million people from Canada. It found those living within 50m of a major road were 7% more likely to develop dementia than people living more than 300m away.
As other factors are associated with living on a busy road, such as high noise pollution and stress, the Alzheimer’s Society points out the study doesn’t prove air pollution causes dementia. “However, it does suggest that the study of air pollution and dementia should be prioritised for future research,” it adds.
There is “concerning” evidence that exposure to air pollution is associated with new-onset type 2 diabetes in adults. One study found living within 50m of a major road, compared with those living more than 200m away, was associated with new-onset type 2 diabetes.
10. Mental health
More frequent and severe flooding is a result of climate change, and health experts are concerned about the effect on people’s mental health, with victims of the 2007 UK floods up to five times more likely to experience symptoms of stress and anxiety.
11. Spread of disease
Changes in climate are likely to alter the geographic range of serious diseases transmitted to humans by, for example, mosquitoes, ticks, and fleas, like malaria and dengue.
Source: Belfast Telegraph
Author: Lisa Salmon