BEIJING (REUTERS) - China will aim to cut solid waste imports to zero by next year as part of its efforts to ease pollution pressures and encourage its recyclers to treat the soaring volumes of domestic trash, a senior environmental ministry official said on Thursday (March 28).

Since the 1980s, China has taken in hundreds of millions of tonnes of foreign paper, plastic, electronic waste and scrap metal for recycling by an army of backyard workshops. Beijing began restricting deliveries last year, while customs authorities have launched a series of crackdowns on waste smuggling, leading to hundreds of arrests.

"China will further tighten restrictions of waste imports and eventually aims to realise zero waste imports by 2020," Qiu Qiwen, director of the Ministry of Ecology and Environment's solid waste division, said on the sidelines of a briefing.

China imported 22.6 million tonnes of solid waste last year, down 47 per cent from a year earlier, the ministry said.

In December, Beijing also vowed to ban imports of more varieties of scrap steel, copper and aluminium starting from July, and the veto will be extended to products such as scrap stainless steel and titanium at the end of this year.

The aim was to block imports of all waste products that could be be sourced domestically. Qiu said products not included on the banned list would also be restricted by next year, but high-quality material would still be accepted.

"If the solid waste ... meets the requirements of China's import standards and doesn't contain any hazards, then it can be treated as common commodities, not waste," he said.

Trash has emerged as one of China's biggest environmental challenges. The country faces a solid waste treatment backlog of around 60-70 billion tonnes, putting it under huge pressure to boost recycling capacity.

It has already launched a scheme to create "waste-free cities" and is building hundreds of "comprehensive recycling bases" across the country. But firms complain that China lacks the infrastructure and waste treatment habits required to create a profitable business.