Summertime is barbecue time. However, when fat reacts with glowing coal, a substance chemists call benzopyrene is created. It is a widespread environmental toxin that can cause cancer in humans. Since buildings were heated with coal and wood for decades, dispersed by chimney smoke, it is now also found in soil and groundwater. A team led by Prof. Arne Skerra from the Technical University of Munich (TUM) has deciphered the binding mechanism of an antibody to benzopyrene—a discovery that could pave the way for an easier method to identify and, hence, remove the toxin.