BEIJING, April 23 (Reuters) – China’s scrap metal imports in March fell by 24.6 percent from a year ago as new curbs on foreign solid waste came into effect, while waste paper imports slid by 54.2 percent and the country imported zero waste plastic. New impurity limits – set at 1 percent for nonferrous metal, and at 0.5 percent for paper, plastics and ferrous metal – were announced by China last year and had already impacted shipments but only officially came into force on March 1. China imported a total of 570,000 tonnes of scrap metal last month, the General Administration of Customs said on Monday, versus 760,000 tonnes a year ago and 440,000 tonnes in February, when the country had a week-long holiday for Lunar New Year. Scrap copper imports were at 220,000 tonnes last month, down 37.7 percent from March 2017. China’s Ministry of Ecology and Environment last week confirmed that imports of Category 7 scrap copper – such as coiled copper cable and waste motors – would be banned from the end of this year. Import quotas for scrap copper have already been falling. Meanwhile, China imported 180,000 tonnes of aluminium scrap last month, up from 119,737 tonnes in February but down 5.6 percent year-on-year. China said on April 2 that it would impose a 25 percent tariff on aluminium scrap from the United States in retaliation against U.S. steel and aluminium tariffs imposed in March. China’s overall imports of foreign solid waste – including waste paper, waste plastics and scrap metal – fell by roughly half from a year ago to 2 million tonnes in March, data earlier this month showed.