Researchers from the University of California, Riverside found that the addition of black carbon reduces the bioavailability, or the fraction of chemicals that can be taken up by organisms, of polybrominated diphenyl ethers (PBDEs) in sediment. They developed a method to measure PBDE bioavailability in sediment and found that reduction in bioavailability varied greatly depending on the type of black carbon; activated carbon showed the best efficiency compared to biochar or charcoal.