(SAN FRANCISCO) — Action star Chuck Norris took on medical device manufacturers in a lawsuit filed in California on Wednesday alleging a chemical used in MRI imaging scans poisoned his wife. Gadolinium that doctors injected into Gena Norris to improve the clarity of her MRIs have left her weak and tired and with debilitating bouts of pain and a burning sensation, the suit filed in San Francisco Superior Court says. Gadolinium is a metal found in so-called contrast agents used in many MRIs.