Similar to ‘forever chemical’ PFAS, medium-chain chlorinated paraffins (MCCPs)—often found in textiles and PVC products—are toxins that can take a long time to breakdown in the environment and negatively impact human health. Scientists at the University of Colorado Boulder have now, in a first for North American, detected these toxins in the air while researching aerosol formation. These airborne MCCPs particles likely entered the atmosphere through biosolids—a fertilizer developed from treated wastewater. They are also known as “forever chemicals” for their tendency to linger in the environment. Of the others, one of the most concerning is a type of toxin known as medium-chain chlorinated paraffins, or MCCPs.