Study links heart attacks to rise in air pollution

By ROGER DOBSON and SEVERIN CARRELL

Small rises in urban air pollution can trigger an increased number of potentially fatal heart attacks, an international study has discovered.

Doctors have found that even slight daily increases in sulphur dioxide - one of the main culprits for the lethal London smogs of the 1950s - will lead to a rise in hospital admissions for heart illnesses.

Professor Jon Ayres, a respiratory expert at Aberdeen University, said: "We found new evidence for the effects of urban air pollution on cardiac diseases in Europe, suggesting that air pollutants could trigger a heart attack in people with vulnerable arteries.

"When this link between pollution and heart disease was first seen, everyone thought there had been some mistake. But we are now building up a body of evidence that there is an effect, and at quite low levels."

The study compared the link between sulphur dioxide levels and hospital admission rates in seven European cities and regions, including London, Birmingham, Madrid, Paris and Rome, with potentially far-reaching conclusions for city councils and environment agencies.

Their results showed that an increase of only 10 micrograms per cubic metre of sulphur dioxide would lead to a 1 per cent rise in hospital admissions for coronary problems within the next 48 hours.

In London, for example, which already produces more than 100 coronary cases a day, this would mean one extra heart patient for every 10 microgram rise in sulphur dioxide pollution.

The report, published in the European Heart Journal, warns that these findings, "if translated to all the European cities, would result in a considerable public health impact".

This conclusion will intensify pressure on Governments and environment agencies to force power stations, shipping companies and industry to cut their sulphur dioxide emissions even further. British councils may also have to ban coal burning in homes.

The dangers of high levels of sulphur dioxide are well known. In the worst of London's smogs in 1952, caused by black smoke and sulphur dioxide from coal fires, deaths due to heart diseases more than doubled.

Doctors also suspect that particulates - ultra-fine particles of soot and unburnedt oil from diesel engine exhausts - can cause heart attacks and lung disease.

Exactly why pollution causes heart problems remains unclear.

One theory is that particles get into the lungs and cause an inflammatory reaction. That may make the blood more sluggish, triggering heart attacks in vulnerable people.

Another theory is that sulphur dioxide may have an effect upon the rhythm of the heart, causing it to beat erratically.

Auckland's problem

* A report for the Ministry of Transport estimated that 436 people died prematurely in the city each year because of air pollution

This included 253 due to vehicle pollution.

* A study this month of more than 40,000 Auckland cars has found between 30 and 40 per cent exceed American exhaust emission limits.

* Auckland rubbish fires annually spew out 110 tonnes of fine soot, 600 tonnes of carbon monoxide and 200 tonnes of hydrocarbons.

- INDEPENDENT