Mercury · When ingested,Ha0,hg2〃 and Hg2 are not toxIC. Harmful forms: methylmercury ion( CH3)Hg+ regardless of the route of exposure hg vapor when inhaled (CH3)Hg+ is produced from mercury ions by methanogens living in sediments (CH3)Hg+ is soluble in water and bioaccumulates in the aquatic ecosystem food chain (in protein-laden tissues) ( CH3)Hg* binds with protein and peptide sulfhydryl groups. It is dangerous to eat large quantities of very big ocean fish such as tuna and swordfish!Mercury • When ingested, Hg0 , Hg2 2+, and Hg2+ are not toxic. • Harmful forms: methylmercury ion (CH3)Hg+ regardless of the route of exposure, Hg vapor when inhaled. • (CH3)Hg+ is produced from mercury ions by methanogens living in sediments. • (CH3)Hg+ is soluble in water and bioaccumulates in the aquatic ecosystem food chain (in protein-laden tissues). • (CH3)Hg+ binds with protein and peptide sulfhydryl groups. • It is dangerous to eat large quantities of very big ocean fish such as tuna and swordfish!