Ozone pollution in Hong Kong at worst level in a decade: environmental report

Ozone pollution is at its worst in nearly a decade, indicating deteriorating regional air quality, an environmental group found.

This was despite a slight improvement in levels of nitrogen dioxide, sulphur dioxide and particulate matters in the first six months of the year compared with the same period last year, the group Clean Air Network said.

The group's mid-year review found ozone levels far beyond World Health Organisation guidelines at all 15 of the city's air quality monitoring stations.

From January to June, average annual concentrations of the pollutant hit 43 micrograms per cubic metre, nearly double WHO's annual recommended concentration level of 23.5mcg per cubic metre.

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