LettersHong Kong’s cleaner transport push must not neglect tyre pollution
Readers discuss the need to monitor tyre pollution in the city, a Chinese film about the Iraq war, and the US midterms
After a summer downpour, run-off from Hong Kong’s busiest roads may carry more than leaves and litter. It can wash accumulated tyre- and road-surface particles, metals and chemical additives into drains and receiving waters.
On July 20, the Hong Kong Observatory reported that heavy rain events lasting one to three hours increased significantly between 2000 and 2024.
Electric vehicles remain essential to cleaner transport. They eliminate tailpipe emissions, support decarbonisation and, through regenerative braking, can reduce brake wear. But every vehicle, whatever its power source, still uses tyres and roads. The interaction releases particles that may become airborne or remain in road dust until intense rain mobilises them.
We do not yet know the scale or composition of this pollution in Hong Kong’s stormwater, where it accumulates, or what environmental or public health risks it may pose. Overseas studies identify potential concerns but cannot reproduce the city’s combination of dense traffic, subtropical weather, vehicle types, road materials and drainage conditions. That uncertainty is a reason to investigate, not ignore, the issue.