Lots of factory closures in China for environmental reviews are happening right now. According to the China Daily, about 10,000 polluting companies were ordered to suspend production or shut down by the end of June. And many factories are experiencing unexpected delays in productions.
Source: http://news.xinhuanet.com/english/2017-04/06/c_136185239.htm
Source: http://usa.chinadaily.com.cn/china/2017-07/31/content_30298900.htm
Environmental inspections have caused great impact on MgO prices. The whole supply chain has been affected by the inspection.
Source: http://www.globaltimes.cn/content/1060076.shtml
Prices of building material RISE 10-20%