and b.m.w. funded research group that study twenty five human volunteers inhaling nitrogen dioxide. says it won t conduct any more tests on animals hopefully not on humans either this comes as europe s car industry fights for a future for the diesel is no dispute that nitrogen oxide pollution is a problem levels are too high in places like dusseldorf munich hamburg. berlin a total of twenty eight german cities exceed limits in some cases dramatically and it s not just germany france has nineteen affected areas including paris and its suburbs britain has sixteen including london in total twenty three of the twenty eight e.u. countries exceed equality norms germany s environmental agency says two thirds of nitrogen oxide is produced by diesel engines even the cleanest diesels produce this toxic gas even mission has summoned nine environment ministers including germany s