Sustainability certification by Marine Stewardship Council may be obscuring labour abuses in seafood supply chains, say researchers Sustainability certification by Marine Stewardship Council may be obscuring labour abuses in seafood supply chains, say researchers The Marine Stewardship Council (MSC), which operates a “blue tick” scheme to indicate the sustainability of fish, has been accused of creating an “illusion” of ethical sourcing, after a study reported that widespread labour abuses have