Better than a decade ago

As yesterday’s pollution levels ranged between moderate and unhealthy – with unhealthy levels rising between noon and 5:00pm in particular – the Guangdong-Hong Kong-Macau Pearl River Delta Regional Air Quality Monitoring Network reported its results, which, surprisingly, shows a reduction of pollution levels over the past years.
‘The long-term downward trend of pollutant levels was evident despite short-term fluctuations,’ notes the release.
Overall, comparing 2016 to the previous year, annual concentration levels of sulphur dioxide in the air – which according to the United States Environmental Protection Agency (EPA) can increase particulate matter (PM) which can ‘penetrate deeply into sensitive parts of the lungs and cause additional health problems’, contribute to acid rain and haze and ‘harm trees and plants’ – was down 8 per cent year-on-year.
A reduction was also seen in respirable suspended particulates (RSPs), of 6 per cent year-on-year, although the level of nitrogen dioxide (NO2) – resulting mainly from the burning of fuel, as in car emissions and power plants – went up by 6 per cent year-on-year during 2016, the only one of the six measured major air pollutants to increase from the previous year.
The report points out, however, that compared with 2006 all but one of the four pollutants measured over the ten-year period decreased in level. The most significant of these was seen in nitrogen dioxide, with a total drop of 74 per cent. Current levels are about 13 ppb (parts per billion), while the EPA notes that the annual mean for NO2 should not exceed 53 ppb. This is a drop from the roughly 28 ppb present in the air in 2006.
Ozone in the air was the only pollutant to increase, with a 4 per cent rise compared to 2006, which was still, however, a 6 per cent decrease from the previous year. Ozone ‘can trigger a variety of health problems, particularly for children, the elderly, and people of all ages who have lung diseases such as asthma,’ notes the EPA, and can be created by reactions with emissions from industrial facilities, vehicle exhaust and gasoline vapours, notes the EPA.
Carbon monoxide and fine suspended particulates (FSPs), whose measurement only began in 2015, both saw decreases, of 1 per cent and 9 per cent, respectively, year-on-year in 2016.