Illegal Chinese production of a banned crude oil-derived chemical used for cheap home insulation is thought to be the main source of rising emissions of gas that is damaging the ozone layer, according to environmental group Environmental Investigation Agency. Two months ago, scientists published a study in the scientific journal Nature, according to which there has been an unexpected and persistent increase in global emissions of the ozone-depleting trichlorofluoromethane (CFC-11) substance that has been banned since 2010. The thing that baffled scientists was that after a constant drop in the atmospheric CFC-11 concentrations between 2002 and 2012, the rate of decline has slowed down by around 50 percent since 2012, suggesting unreported new production. The Environmental Investigation Agency published a new report on Monday, blaming the inexplicable rise in the chemical to illegal production of rigid polyurethane (PU) foam in China, used as insulation in its booming construction sector. […]