The liver does not filter mercury in a good sense, and accumulation of mercury in the liver is dangerous. The only option is to minimize exposure to mercury containing fish. Eat fish sources that are smaller, and therefore lower on the food chain, as less bioaccumulation of mercury will have occured.
In terms of data, I have none. You really need to search for information on individual fish sources and determine what you personally consider as a resonable amount of risk when comparing "safe" consumption levels.