Tag Archives: NO2

City Traffic.

New research says traffic exhaust is giving millions of kids asthma all around the world

Traffic-associated pollution leads to roughly 4 million cases of asthma in children worldwide each year, a new study reports.

City Traffic.

Image via Pixabay.

The team looked at 125 cities around the world, keeping track of the nitrogen oxide (NO2) levels in their air, and how it related to new pediatric cases of asthma. The study, based on data from 2010 to 2015, estimates that 4 million children worldwide develop asthma each year due to NO2, with 64% of these new cases occurring in urban areas.

The gas accounted for anywhere between 6% (Orlu, Nigeria) to 48% (Shanghai, China) of these cases, the authors report. Overall, NO2’s contribution to new cases of pediatric asthma exceeded 20% in 92 cities, they add, in both developed and emerging economies.

Bad air

“Our findings suggest that millions of new cases of pediatric asthma could be prevented in cities around the world by reducing air pollution,” said Susan C. Anenberg, PhD, an associate professor of environmental and occupational health at Milken Institute SPH, and the study’s senior author.

“Improving access to cleaner forms of transportation, like electrified public transport and active commuting by cycling and walking, would not only bring down NO2 levels, but would also reduce asthma, enhance physical fitness, and cut greenhouse gas emissions.”

Asthma is a chronic disease that involves inflammation of the lung’s airways, making it hard (sometimes impossible) to breathe. It is estimated that 235 million people worldwide currently have asthma, varying in intensity from wheezing to life-threatening attacks. This study is the first to take a look at how traffic-related nitrogen dioxide fits into the asthma picture. The work relied on a method that takes into account high exposures to NO2  that occur near busy roads, Anenberg explains.

For the study, the team linked together global datasets of NO2 concentrations,  population distributions, and asthma incidence rates with epidemiological evidence relating traffic-derived NO2 pollution with asthma development in kids. This wealth of data allowed the team to estimate how many new cases of pediatric asthma are attributable to NO2 pollution in the 194 countries and 125 major cities they studied.

Here are some key takeaways:

  • Roughly 4 million children developed asthma, each year, from 2010 to 2015 due to NO2 pollution (primarily from motor vehicle exhaust).
  • NO2 accounted for between 6% to 48% of pediatric asthma incidence. Its contribution exceeded 20% in 92 cities located in developed and emerging economies.
  • The ten highest NO2 contributions were estimated for eight cities in China (37 to 48% of pediatric asthma incidence) followed by Moscow, Russia and Seoul, South Korea, both at 40%.
  • In the US, the top-five most affected cities (as judged by percentage of pediatric asthma cases linked to polluted air) are Los Angeles, New York, Chicago, Las Vegas, and Milwaukee
  • China had the largest national health burden associated with air pollution at 760,000 cases of asthma per year, followed by India at 350,000, and the United States at 240,000.
  • In general, cities with high NO2 concentrations also had high levels of greenhouse gas emissions.

The World Health Organization (WHO) has set Air Quality Guidelines for NO2 and other air pollutants. For NO2, that guideline pins about 21 parts per billion for annual average levels as being safe. The researchers estimate that most children live in areas that conform to this guideline, but say that 92% of new pediatric asthma cases attributable to NO2 sprung up in areas that met the WHO guidelines.

“That finding suggests that the WHO guideline for NO2 may need to be re-evaluated to make sure it is sufficiently protective of children’s health,” said Pattanun Achakulwisut, PhD, lead author of the paper and a postdoctoral scientist at Milken Institute SPH.

The team, however, is confident that we can do better. Many of the solutions aimed at scrubbing cities of the greenhouse gases in their air would also reduce NO2 levels, thus helping prevent new cases of asthma.

The paper “Global, national, and urban burdens of paediatric asthma incidence attributable to ambient NO2 pollution: estimates from global datasets” has been published in The Lancet Planetary Health journal.

The UK government is being taken to court over air pollution…again

Beginning today, environmental lawyer group ClientEarth is taking to court against the UK government in the second lawsuit between the two. CE claims that the lawmakers have failed to take serious action to limit air pollution, leading to the deaths of tens of thousands.

Canary Wharf under smog.
Image credits Matt Buck / Wikimedia.

European cities have some of the highest levels of atmospheric nitrogen dioxide (NO2) in the world, mostly due to the high ratio of diesel vehicles in use. Since regular exposure to this gas is very hazardous, in 1999 the EU set legal limits for how much of the stuff can be puffing about in the air we breathe — limits which went into effect in 2010.

Under this law, the city of London got an hourly limit of 200 micrograms NO2/sq meter of air. However, to say that authorities didn’t try to abide by these figures would be an understatement.

“[London was] only permitted to breach those limits 18 times in a year. However, [the city] weezed past the yearly limit just 8 days into the year,” Andrei wrote in January.

“[London polluted] about 40 times more than it should under EU (European Union) regulation.”

Love is in the air, but so is pollution

And it’s not just London. Only five of the country’s 43 air quality zones meet the EU’s limits. Needless to say, this doesn’t sit well with the people who have to breathe it all in.

So in 2011, backed by rising public displeasure on the issue, ClientEarth took the UK government to court over their lack of action on cleaning the air. The case was handled by the European Court of Justice, which ruled in 2014 that national courts can and should ensure their governments take pollution under legal limits “as soon as possible”. From then on, the UK’s Supreme Court handled the suit. In April 2015 it ordered the environmental minister to take “immediate action” by consulting with the public and putting together a plan to clean the air.

Clean air plz we’re dying — Love, Supreme Court, xoxo.

But very little has been done. The plan set out back in December was so vague that CE said they’ll take the UK government to court again, unless their game improves, literally days after it was made public. In effect, the plan estimated compliance to the limits by 2025. To add insult to injury, DEFRA announced it will begin public consultations on the plan involving the creation of five clean air zones — which will not restrict diesel vehicles — just last week, mere days before the second trial.

“It’s taken 18 months for ministers to even begin a consultation,” says James Thornton, head of ClientEarth. “This is a woefully inadequate response to the air pollution crisis.”

So CE is taking to courts against the UK’s government yet again. Supporters say that the government has been deliberately stalling, based on models which predict that emissions would decline as older vehicles get phased out without the ruling body having to do much. They point out that, as Volkswagen recently proved, NO2 and particulate matter emission measurements for modern diesels (on which these models are based) are flat-out lies.

“Defra’s latest figures estimate there are 40,000 early deaths across the UK every year because of air pollution. The government is acting unlawfully by refusing to turn this situation around. It is failing morally and it is failing legally to uphold our right to breathe clean air,” ClientEarth CEO James Thornton said.

More decisive action is needed

“The government must come up with far bolder measures, ready to face this issue head-on,” Thornton added.

“Air quality in this country is nothing short of a public health crisis.”

So what would constitute “bolder measures”? Phasing out diesel is the first obvious step. For starters, I find it mindboggling that the UK is still handing out incentives for diesel cars — so maybe start there? Something along the lines of “scrap your own diesel and get a discount on this brand new *insert literally anything else here*”. Then the implementation of real Clean Air Zones would prevent the most polluting vehicles from entering towns or city centers. Retrofitting of buses and trucks to make them gentler on the environment and lungs, a cleaner public transport network, and so on. There’s a lot to do here.

Clean energy would also help a lot to improve air quality.

But first this case needs to happen, and the UK government needs to understand that pollution is a very real hazard to the public, one which they have a moral — and legal — obligation to solve.

The trial will take place on Oct. 18 and 19, with the ruling to be announced two weeks after the hearing.