Proteins play a crucial role in how certain chemicals build up and spread in organisms. In a study comparing different chemicals in a lake, researchers found that per/polyfluoroalkyl substances (PFASs) interact strongly with proteins in biofilm, leading to higher levels in snails compared to other chemicals. PFASs also showed greater increase in concentration from biofilm to snails than other chemicals tested. The study suggests that proteins help PFASs accumulate and spread in the environment.