Could air pollution be linked to higher crime rates?

Well, now I fancy some burgling. Image: Getty.

The impact of air pollution on human health is well-documented. We know that exposure to high levels of air pollutants raises the risk of respiratory infections, heart disease, stroke, lung cancer as well as dementia and Alzheimer’s disease. But there is growing evidence to suggest that air pollution does not just affect our health – it affects our behaviour too.

Lead was removed from petrol in the USA in the 1970s in response to concerns that vehicle emissions could be contributing to behavioural problems, learning difficulties and lowered IQ among children. In particular, childhood exposure to lead increases traits such as impulsiveness, aggression and low IQ – which can influence criminal behaviour. Taking lead out of petrol has since been linked with a 56 per cent drop in violent crime in the 1990s.

Short-term exposure to air pollution, especially sulphur dioxide, has been associated with a high risk of hospital admissions for mental disorders in Shanghai. And in Los Angeles, a study concluded that higher levels of particulate matter pollution increases teenage delinquent behaviour in urban neighbourhoods – though of course these effects are compounded by poor relationships between parents and children, as well as social and mental distress on the part of the parents.

It now believed that exposure to air pollutants can cause inflammation in the brain. What’s more, fine particulate matter is harmful to developing brains, because it can damage brain and neural networks and influence behaviour.

Criminal behaviour

The evidence so far suggests that air pollution has the capacity to increase bad behaviour – especially among young people. But further research indicates that it can have even more serious impacts. One study of air pollution and crime in 9,360 US cities suggests that air pollution increases crime. Polluted air increases anxiety, which can in turn lead to a rise in criminal or unethical behaviour. The study concluded that cities with higher levels of air pollution had higher levels of crime.

Recent research from the UK provides provides more information on this issue, by comparing data for 1.8m crimes over two years with pollution data from London’s boroughs and wards. The analysis considered factors such as temperature, humidity and rainfall, days of the week and different seasons.

The air quality index (AQI) reports how clean or polluted the air is each day. Researchers found that a 10 point raise in the AQI increases the crime rate by 0.9 per cent. Levels of crime in London are therefore higher on the most polluted days. The study found that air pollution influenced crime in London’s wealthiest and poorest neighbourhoods.

Specifically, the findings linked higher air pollution levels in London to increases in petty crime such as shoplifting and pick-pocketing. But it is worth noting that the researchers found no significant impact on serious crimes such as murder, rape or assault resulting in severe injury.

The stress factor

Exposure to poor quality air can increase the stress hormone cortisol, which can influence risk perception. Higher levels of risk taking is one reason why there is a rise in criminal activity on polluted days. The researchers conclude that reducing air pollution could reduce crime.

SMog: a recipe for misbehaviour. Image: Ian D. Keating/Flickr/creative commons.

But other social and environmental factors may also influence people’s behaviour. Environmental disorder – such as broken windows and graffiti – can induce social and moral disorder. The broken window theory suggests that signs of disorderly and petty criminal behaviour trigger more disorderly and petty criminal behaviour, causing this behaviour to spread.


It is becoming clear the effects of polluted air goes beyond the well-known impacts on health and environment. Yet air pollution remains high in many countries. According to the World Health Organisation, nine out of ten people worldwide are now breathing in toxic air.

There’s still a lot we don’t know about how individual air pollutants can affect health and behaviour, and how this differ with gender, age, class, income and geographic location. The link between high levels of air pollution and increases in type of behaviour requires further robust evidence to determine a stronger causal link.

But there’s plenty of evidence to prove that poor air quality is bad for both our physical and mental health. Concerted action by national and local government is required to tackle the problem by developing more sustainable transport, efficient and renewable energy production and use, and waste management.

The ConversationThe UN BreatheLife campaign is now challenging citizens to take action by leaving their car at home and use alternative forms of transport for at least the distance of a marathon (42km/26 miles) for one month. We all have a role to play in ensuring we can all breathe clean air, and gain the benefits of improved physical, mental and social well-being.

Gary Haq, SEI Associate, Stockholm Environment Institute, Environment Department, University of York.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

In New Zealand, climate change is driving an eco-nationalist revival

The green and pleasant land of the South Island. Image: Getty.

“Ten years ago I would have called them settler f*****g land squatters,” Mike Smith, Maori-dom’s most tenacious activist, said last November as he reflected on the agriculture industry’s central role in driving climate change. “Now I have to try and get these people on board.”

Smith is infamous for taking a chainsaw to Auckland’s most prominent tree on a damp October night in 1994 in protest of the “Pākehā” – or white European –dominated government’s fiscal envelope restraining treaty settlements. Now he’s turned his hand to another cause close-to-home for the Maori, New Zealand’s indigenous population: the environment.

“We’re super vulnerable, like we are to anything,” Smith says. “When it comes to climate change it’s like the poorest people in the world are going to be hit the hardest first, and that’s a lot of us.”

Prime Minister Jacinda Ardern appears, at least rhetorically, the most sympathetic leader to his cause in a decade. In her campaign launch speech late last year, she made the future government’s position clear: “Climate change is my generation’s nuclear free moment.”

This message should resonate with followers of her Labour party: the NZ left has long nurtured an environment-orientated “culture-of-protest”. So Ardern’s call to arms was bound to gain her loyal support among children of the 1960s and ‘70s, who led the march against nuclear ship visits, spurring on the government of the time to wriggle out from the US nuclear umbrella, and place a ban on foreign nuclear ship visits.

Now, it is to the tycoons of deep sea oil exploration they aim to close NZ’s ports.

In this, Smith is not short of support locally, with marches run by grassroots organisations and international animal welfare funds beginning to gain traction with every day New Zealanders. In this, Ardern’s prediction is correct: the Coal Action Network Aotearoa (CANA), is reminiscent of the Campaign for Nuclear Disarmament (CND), an earlier cluster of left-wing pacifists and nature lovers who drove the creation of the nuclear free zone.  

In December, 15,000 passionate protesters marched through the capital. And with the government’s recent ban of offshore oil exploration projects, Jeanette Fitzsimons, former Green party co-leader and the head of CANA, is optimistic about similar change to the energy and farming sectors.

The Labour-NZ First-Green party coalition seems focused on setting a new global precedent, weaning NZ away from a United States which has jettisoned the Paris Agreement. The move replicates another 20 years ago, when New Zealand’s anti-nuclear movement was central to an upsurge in New Zealand nationalism. Now, the same sense of going it alone on foreign policy is apparent both locally and in Parliament.

Dr. Gradon Diprose, a senior lecturer at Massey University, argues that this echoes an older expression of colonial nationalism, that saw “New Zealand as a land of natural abundance”. This: “eco-nationalism” is centered on “protecting certain visions of picturesque landscapes and unspoiled natural beauty”. The slogan “Clean, green New Zealand” is prevalent in popular culture and tourism marketing. The public seems to have latched onto it too, and ranked keeping NZ’s waterways “clean and green” top of a recent survey of of kiwis’ top concerns.

Three decades ago, it was the 10 July 1985 sinking of the Greenpeace flagship Rainbow Warrior that thrust local activists’ fears into the public eye, resulting in an almost nation-wide expression of climate-protectionism.


The bombing, a French intelligence operation sparked by Greenpeace’s calls for an end to foreign nuclear testing in the Pacific, galvanised a great deal of change to New Zealand’s overseas defence policies. A lack of censure from New Zealand’s Western allies drove Wellington to distance itself from the United States, while the shock of seeing a friendly nation violate NZ’s sovereignty left many at home seething.

Thirty years on, the foreign policy split throughout the Anglosphere, regarding Russian-Western relations, globalism, and the old international rules-based order, is becoming wider. Climate change is just the tip of the iceberg.

Most Kiwis you talk to will shake their heads in disapproval at US president Donald Trump’s scandalous outing last year in Helsinki. But US defiance of internationally brokered climate resolutions is something they can see clearly reflected in rural communities across the country.

The country saw records broken at both ends of the extreme weather spectrum last year. As 2018 kicked off, Kiwis sweltered through the hottest summer on record, while in Golden Bay, a small inlet near the northern tip of the South Island, residents endured the largest flood in 150 years. So, when President Trump tweets “So much for Global Warming”, the majority of New Zealanders look back fondly on NZ’s 1985 decision to boycott the “ANZUS” treaty, putting New Zealand at odds with its war-time ally America on defence legislation.

Public calls to take the same track on environmental regulation have become louder in the wake of Donald Trump’s election. The former US Secretary of State, Rex Tillerson, received a frosty “unwelcome” while on a flyby to the capital in 2017, with the New York Times’ Washington correspondent, Gardiner Harris remarking: “I’ve never seen so many people flip the bird at an American motorcade as I saw today”. Protests against President Trump’s stance on climate change are beginning to gain greater traction further still, with the hundred-strong “march for science” setting the tone for the new government later that year.

New Zealand certainly isn’t afraid of radicalism, and its activists are persistent. It’s already banned single use plastics in supermarkets. Plenty more is to come, Smith says.

And yes, reform is going to inhibit sometimes vital industries: “It doesn’t matter which way you spin the dice on this, whatever’s being done is going to hurt. People who are looking for a painless way of mitigating climate change, [but] I don’t think there is one.”

But among Smith’s troupe of climate agitators, the feeling is that, without drastic change, “the land”, the heart of the Maori ethos, is going to be hurt far more.

Back in Auckland, NZ’s financial hub, an electric scooter craze is gripping the city. This, too, has gained the support of local environmentalists. In New Zealand, a national sense of pride is always coupled with a certain eccentricity. In a country this size, change always starts small.