Pollution readings at air-monitoring stations reached the highest levels on Wednesday afternoon, just hours after the Environmental Protection Department issued health warnings earlier in the day.
Mong Kong in Kowloon, plus Yuen Long and Tsuen Wan in the New Territories all recorded levels classed as a ‘serious’ health risk.
Meanwhile, readings for PM 2.5 – fine airborne particles with a diameter of 2.5 microns or less – were six times higher than levels recommended by the World Health Organization in Tsuen Wan and Tung Chung on Lantau Island, Headline Daily reported.
A release from the Environmental Protection Department explained that higher than normal levels of nitrogen dioxide and particulate matter were recorded on Wednesday morning as the city was affected by an airstream with higher background pollutant concentrations and the light wind hindered effective dispersion of air pollutants.
Sunshine enhanced photochemical smog activity and the formation of ozone and fine particulates, resulting in the city’s bad pollution.
Clean Air Network, an independent non-government group focused on air pollution issues in Hong Kong criticized the government for using meteorologists to explain the problem – while ignoring uncontrolled growth in the number of cars in the city, particularly old vehicles that emit excessive air pollution.
The association said roadside air quality had deteriorated, with the level of nitrogen dioxide and PM 10 – inhalable particles of 10 microns or less, rising by 5% and 3% respectively in 2017, compared to levels in 2016.