Chapter 8

Mixtures


How can we find out if mixtures play a role for the risk assessment?

Bisphenol A was phased out from commerce in Europe in 2020 due to its classification as a substance of very high concern. Numerous replacement products are entering the market.
How can we find out if these replacement products are safe? What makes it particularly difficult if one chemical is replaced by several chemicals?

Chemicals occur rarely alone but in mixtures with other chemicals. In artificial football pitches granules of recycled tyre materials are used as infills. Amongst other components, these infills contain Polycyclic aromatic hydrocarbons (PAH)s. PAHs are actually mixtures of hundreds of distinct polyaromatic compounds. The EU uses a mixture of eight PAHs as indicators, including Benzo[a]pyrene (BaP), Benzo[e]pyrene (BeP), Benzo[a]anthracene (BaA), Chrysene (CHR), Benzo[b]fluoranthene (BbFA), Benzo[j]fluoranthene (BjFA), Benzo[k]fluoranthene (BkFA), Dibenzo[a,h]anthracene (DBAhA). How can we account for mixtures in risk assessment? What assumptions do you have to make? Would that assumptions likely be fulfilled for these eight PAHs?