German automakers Volkswagen, BMW and Daimler backed studies that exposed humans and monkeys to exhaust fumes and nitrogen dioxide, the Washington Post reports. European Research Group on Environment and Health in the Transport Sector (EUGT), which conducted the studies in 2014, never published results.

Why it matters: Experiments reportedly forced monkeys to "inhale exhaust fumes from a Volkswagen Beetle car and an older pickup truck for several hours in an attempt to prove the Beetle’s clean emission standards." Human subjects "were asked to inhale nitrogen dioxide (NO2), a gas that is primarily emitted through traffic," according to the Post.

What they're saying:

• “We are shocked by the extent and application of the studies ... We condemn the experiments in the strongest terms," Daimler said in a statement.
• Both Daimler and BMW denied having knowledge of the EUGT study, reportedly led by Volkswagen.
• Volkswagen blamed “mistakes and misjudgments of individuals.”
• A spokesperson for German Chancellor Angela Merkel said, the experiments "are in no way ethically justifiable and they raise serious questions for those who backed them."