Haze 'is bad for your heart'

Victoria Vaughan Straits Times 14 Jun 10;

HAZE is bad for your heart, with evidence linking it to heart attacks and cardiovascular death having 'strengthened substantially', warned the American Heart Association (AHA) in a scientific statement on its website.

The culprit is particulate matter less than 2.5 micrograms in diameter, known as PM2.5, the main component of haze.

The warning comes at a time when the haze season, caused by widespread burning of forests in Indonesia, is about to begin again in the region from next month.

Satellite pictures in April showed 3,166 hot spots in the region, much higher than the 2,427 detected in April last year, prompting fears that the haze will return even stronger in the traditional burning season from July to September.

In Singapore, air quality is calculated using the Pollutant Standards Index (PSI), which does not measure PM2.5 levels. Instead, it measures the amount of PM10, a larger particulate matter in haze.

Doctors say the very small PM2.5 particles may get into a human's blood circulation and cause direct harm to the person.

Singapore's National Environment Agency (NEA) said it monitors PM2.5 levels through its 11 air-monitoring stations islandwide, although this measurement is not made publicly available each day.

Instead, the agency lists the annual average reading in its annual report.

The PM2.5 average here in the last two years were both above the 'safe' level recommended by the World Health Organisation (WHO) and the United States Environmental Protection Agency (EPA).

They were 16 micrograms (ug) per cubic m and 19 ug per cubic m respectively, which exceeds both the WHO standard of 10 ug per cubic m and the EPA standard of 15 ug per cubic m.

But the NEA said the levels clocked here were comparable to that in other major cities like London, New York, Los Angeles and Paris. The level was higher last year compared to the year before because of 'transboundary smoke haze', it added.

The PSI was a standard Singapore adopted from the EPA 19 years ago and daily PSI readings are made publicly available on NEA's website. The US agency no longer uses this index, having switched to the Air Quality Index (AQI) in 1999. This index measures PM2.5 levels in the air.

When asked if it would consider switching its method of calculating air quality, an NEA spokesman said there was 'no internationally-harmonised protocol' for reporting air quality indices.

'The PSI system that NEA has adopted has served us well in issuing appropriate public health advisories when Singapore's air quality was adversely affected by transboundary smoke haze in the past,' said the spokesman.

Other places such as Hong Kong, Malaysia, Brunei, Indonesia, Britain, France and Belgium also used indices which measured PM10 rather than PM2.5, the agency pointed out.

The NEA did not elaborate on why PM2.5 levels are not made available daily.

However, experts felt it was time for more regular updates on PM2.5 levels.

National University of Singapore climatologist, Associate Professor Matthias Roth, felt hourly values should be made available to the public.

'It's important for the public to know about the levels of PM2.5 in the air as these small particles have a strong association with most types of respiratory illness and even mortality,' he said. 'Reporting an annual average has limited use as it will have a low bias due to the numerous rainy days when concentration of air pollutants are minimal.'

When asked if the public should be concerned about PM2.5, Singapore's Health Ministry said: 'The PSI cut-offs are internationally accepted standards. People are advised to avoid vigorous outdoor activities at PSI more than 100 because air quality is unhealthy beyond this level. However, these are general public health guidelines and individuals may choose to avoid vigorous outdoor activities at PSI levels less than 100 if they are still concerned.'

According to the WHO, air pollution is estimated to cause about two million premature deaths worldwide each year.

But while AHA's warning seems pretty dire, heart doctors here say they have not seen increased incidents linked to haze.

Dr K. Gunasegaran, a senior consultant at the Department of Cardiology in the National Heart Centre, noted the haze situation here is not particularly bad. 'Generally, it is not prevalent all year round,' he said.

But while the centre has not seen an upswing in cardiac failure during hazy periods, he said patients with underlying conditions such as lung disease could be at higher risk.

He suggested such individuals stay indoors during periods of haze and seek early medical attention if they feel unwell.

Are we prepared?
Straits Times 21 Jun 10;

THE article, 'Haze 'is bad for your heart'' (last Monday), said that with more hot spots detected in the region in April this year compared with the number last year, the haze may return stronger in the coming months.

Are we now better prepared to counter a thicker haze should that happen?

Would more data on pollutants, such as particulate matter PM10 and PM2.5, be made known when their levels are abnormally high? Should hourly measurements be disclosed?

And do people here know the dos and don'ts if the situation becomes life-threatening? What safety procedures are in place or recommended to deal with a critical situation - at homes and in schools, hospitals, coastal areas and other open areas? What are the ways to inform the public of precautions and procedures?

Freak weather conditions seem to occur quite often around the world these days and must be factored into our disaster preparation planning.

When pollutant levels are dangerously high and an unexpected windless condition suddenly develops, the situation could become life-threatening. Britain experienced two smog disasters in the last 60 years due to freak weather conditions - one in 1952 and another in 1991.

If a freak, windless condition develops here amid a huge gathering of pollutants in the air, what should we do?

Do we have the technology and equipment to create winds or make rain, or protect our drinking water from pollution?

To depend totally or only on our breezy weather to avert haze disasters is unwise.

Ng Ya Ken

Burning issue
Straits Times Forum 21 Jun 10;

'Reduce outdoor burning of incense and paper offerings here.'

MADAM LEE SIEW KENG: 'I read with concern last Monday's article, 'Haze 'is bad for your heart''. For those living near temples that burn incense and paper offerings, this presents a double whammy. There is a limit to what we can do about forest burning in Indonesia, but surely we can reduce outdoor burning of incense and paper offerings here. Smoke absorbers should be installed in temples if burning cannot be avoided. We should also limit the hours during which offerings can be burned. Getting temples to plant more trees to absorb the smoke may also help. Smaller, covered kilns should be used and larger offerings should be burned in state incinerators.'