and parts supplier barsh the tests concluded normal much region dioxide emissions had no negative effects on people and apparent all clear for diesel and the snub to the world health organizations research its conclusion was rather different namely that these little missions caused cancer the human tests are a new low point for carmakers in the admissions crisis they follow revelations last week that monkeys were forced to inhale curfew is in two thousand and fourteen something v.w. has since apologized for in twenty fifteen the emission scandal showed you had spent years manipulating its vehicles microbes and dioxide output the carmaker had hoped to leave all that behind but these latest revelations suggest that's unlikely at least any time soon. now for more on the story from d.w. science joins me in the studio welcome derek good to have you why would car makers want to know how the nitrogen how much nitrogen dioxide is actually hazardous to people how much they can have before they get sick isn't this no one already well obviously it's not that nitrogen dioxide and high concentrations