Laboratory tests conducted on North American populations of zebra mussels have demonstrated the ability of adult zebra mussels to accumulate hydrophobic aquatic contaminants from algae and sediment particles. Uptake from these sources was slower than uptake from water (Bruner et al. 1992). Contaminants not retained by the zebra mussel are deposited in mussel feces and pseudofeces where they can affect invertebrate surface feeders. One hydrophobic contaminant studied was pentachlorophenol (PCP). Fisher (1992) has used PCP to show that zebra mussel bioaccumulation is related to temperature and pH and has reported that D. polymorpha is well-suited for contaminant bioaccumulation due to the rapid filtration of water for food and oxygen and a lipid content of over 14 percent. The mussels can also avoid temporary adverse physical or chemical conditions by closing their valves and thus survive in areas that are associated with contaminants. Additional details and data relating to laboratory bioaccumulation by the zebra mussel can be found in Fisher et al. (1993).
These studies by Fisher et al. (1993) indicate that these mussels are able to create dense populations at locations where contaminants are available and filter water to accumulate and retain contaminants, especially hydrophobic or lipophilic compounds. Although it was found that bioaccumulation is greater at higher temperatures, the relative body burden of contaminants may be high at low temperatures as well, because whatever contaminants are accumulated are released very slowly at temperatures of less than 10 °C.