A tyre pile burns out of control in California – similar fires are seen across the world, with one in Kuwait recently claiming the record as the largest

Around 3,400 tonnes of tyres were dumped in landfill in 2019, the latest year with data recorded, according to government figures revealed to LegCo today.

That represents 285,000 car tyres or 155,000 truck tyres, and is around 15% of all the tyres retired each year, according to transport minister Frank Chan Fan.

Responding to a question from transport panel chairman Frankie Yick Chi-ming, Chan said just 6,500 tonnes of tyres were recycled locally in 2019, down 30% from 2017. With 100 tonnes exported for recycling, that yields a recovery rate of just 23% of all tyres retired.

Figures of landfilled tyres and recycled tyres are compiled from separate agencies with differing methodologies and do not tally: according to landfill figures, the total tyre waste in Hong Kong in 2019 was 22,667 tonnes, or around 1.9 million car tyres; while according to recycling figures, the total waste was 28,696 tonnes.

Of those recycled locally, 80% were re-treaded for re-use, while 20% were granulated into raw material for producing rubber powder and paving blocks. Highways Department says it is trialling the use of waste tyres to make new road surfaces, although no research has risen above the pilot stage.

In response to a question on whether the government would consider a “polluter pays” principle for tyre waste, Chan said the government would “examine the necessity”.

He said the government has subsidised an EcoPark tyre recycler with around HK$8 million this year “to enhance its operational efficiency and transformational upgrade by purchasing equipment for shredding waste tyres, separating steel wires, granulating rubber and separating fibres, for turning waste tyres into rubber powder, steel wires, paving blocks and rubber mats.”

But Chan could not explain why the number of tyres recycled every year has been falling, despite government investment in the sector.

Meanwhile, new research from Oxford-based research house Emissions Analytics found tyre wear to be 1,000 worse than engine exhausts in terms of pollutants.

“Harmful particle matter from tyres – and also brakes – is a very serious and growing environmental problem, one that is being exacerbated by the increasing popularity of large, heavy vehicles such as SUVs, and growing demand for electric vehicles, which are heavier than standard cars because of their batteries,” says the firm.

According to Emissions Analytics, non-exhaust emissions are believed to constitute the majority of primary particulate matter from road transport, including 60 percent of cancer-causing PM2.5.