China has publicly accused dozens of firms, including some of its largest state enterprises, of exceeding pollution limits and breaching monitoring standards, as concerns grow that the slowing economy is undermining a five-year war on pollution. In lists published by the Ministry of Ecology and Environment over the past week, subsidiaries of state giants such as China Baowu Steel Group and the Aluminium Corporation of China were cited and fined for breaching emissions standards among other violations. China has been stepping up its supervision capabilities and has plugged thousands of factories into a real-time emissions monitoring system, but enforcement remains one of its biggest challenges. The ministry has continued to warn that China’s slowing economy had given some regions an excuse to “loosen their grip” on environmental protection. In the first quarter of this year, air quality in smog-prone northern regions fell compared with last year, and some regions also saw pollution readings in major lakes and rivers rise over the period. A notice published last Friday said as many as 82 Chinese enterprises exceeded waste water emissions standards in the fourth quarter of 2018, including 44 sewage treatment plants and six waste water treatment facilities. A unit of the Aluminium Corporation of China in Shanxi province was named as one of five “serious offenders”. China’s green efforts hit by fake data and grass-roots corruption It said the unit had exceeded emissions restrictions for a total of 92 days during the period. The firm did not respond to requests for comment. As well as being fined, the companies cited were told to restrict operations until problems were resolved. The biggest fine was meted out to a waste water treatment plant in Liaoning province, which was ordered to pay 7.2 million yuan (US$1 million). In a separate review of monitoring standards in the Yangtze River Delta and the Fenwei plain regions, the ministry identified more than 300 firms for equipment quality violations and exceeding waste water discharge restrictions. It found only 22 per cent of equipment was of the required standard. The list included a special steel producing unit of Baosteel, China’s biggest steelmaker. Baosteel did not respond to a request to comment.