PCBs are industrial chemicals which have been linked to cancer and birth defects.
In recent tests, environmental activists checked 10 different fish oil supplements and found that all contained PCBS, and three brands had much more than allowed by law.
Attorneys have now filed suit against eight fish oil producers and retailers including CVS, GNC and Rite Aid.
CVS, Rite Aid and Omega Protein declined to comment on the lawsuit.
GNC, Now Health Group, Twin Lab and Pharmavite, the maker of Nature Made products, all say their fish oil supplements pass strict tests and comply with all state and federal laws.