Externality watch: Air pollution leads to 7 million deaths

From BBC news, air pollution caused 7 million deaths in 2012:

Seven million people died as a result of air pollution in 2012, the World Health Organization estimates.

Its findings suggest a link between air pollution and heart disease, respiratory problems and cancer.

One in eight global deaths were linked with air pollution, making it “the world’s largest single environmental health risk”, the WHO said.

Nearly six million of the deaths had been in South East Asia and the WHO’s Western Pacific region, it found.

Largest single environmental health risk? I hadn’t hear that before but it makes sense because air pollution is a pretty much global phenomenon.

In general, environmental economists tend to think that pollution is not “internalized” meaning that the level of pollution is above the level which is economically efficient. Under economic efficiency there would definitely still be some air pollution because, although the pollution is costly, it would be even more costly to eliminate the pollution entirely.

Here’s how air pollution affects health:

Reducing air pollution could save millions of lives, said the WHO.

WHO family, woman and children’s health assistant director-general Dr Flavia Bustreo said: “Cleaning up the air we breathe prevents non-communicable diseases as well as reduces disease risks among women and vulnerable groups, including children and the elderly.

The WHO assessment found the majority of air pollution deaths were linked with cardiovascular diseases.

For deaths related to outdoor pollution, it found:

  • 40% – heart disease
  • 40% – stroke
  • 11% – chronic obstructive pulmonary disease (COPD)
  • 6% – lung cancer
  • 3% – acute lower respiratory infections in children

For deaths related to indoor pollution, it found:

  • 34% – stroke
  • 26% – heart disease
  • 22% – COPD
  • 12% – acute lower respiratory infections in children
  • 6% – lung cancer

The Cheapest Way to Skin a Cat

BBC News reports on a study arguing that pollution targets in the European Union are not strict enough:

A study confirming a link between atmospheric pollution and heart-attack risk strengthens the EU case for tougher clean-air targets, experts say.

Research in the BMJ looking at long-term data for 100,000 people in five European countries found evidence of harm, even at permitted concentrations.

Experts stressed that the risk to an individual was still relatively small.

And some argued the results were not conclusive as they did not take account of previous exposure to higher levels.

All this seems fine, but the next paragraph struck me:

Other factors, such as smoking or having high blood pressure, contribute more to a person’s risk of heart attack than pollution from traffic fumes and industry, they say.

It may well be that smoking and high blood pressure contribute more to the risk of a heart attack than local pollution, but this paragraph seems to imply that the “some experts” are saying we shouldn’t work on cutting down pollution and instead should be more concerned about battling smoking and high blood pressure. (And I’m not saying this is what the experts are saying, it’s just the impression that the paragraph gives the reader.)

In environmental economics we learn about cost-effectiveness analysis.  Cost-effectiveness analysis is used to determine the least-cost way to achieve some goal.  So, for example, if we want to reduce the risk of heart attack, we might put resources into discouraging smoking (anti-smoking campaigns), battling high blood pressure (anti-salt campaigns?), lowering local pollution (emissions taxes), or other strategies. We then try to determine how much we should invest in each strategy to reach a given goal (e.g. lowering the risk of heart disease by 10%) in the cheapest – that is, most cost-effective – way.

So, even though smoking and high blood pressure lead to a greater risk of heart attack than local pollution, it may yet be that, for a given reduction in the risk of a heart attack, it is more cost-effective to put our efforts into battling local pollution. Whether it is actually more or less cost-effective is another issue – I don’t know the answer because I haven’t studied the issue.  But unfortunately, while the article cites experts from environmental and respiratory medicine, it does not cite the views of any economists who have studied the issue.

That’s how an environmental economist would think about this issue…