Eat more fish it's healthy -- that's what we are constantly being told.
Fish is healthy, but almost all fish -- according to the government -- contain some mercury, which is not so healthy. Mercury can damage the nervous system, which is why the government says pregnant women and children should avoid or limit fish high in mercury.
"The problem is when you buy fish at the market, there are no labels to tell you how much mercury is in that fish," says Buffy Martin Tarbox of GotMercury.org, and she's lobbying to change that.
Mercury expert Dr. Jane Hightower agrees.
"The more high-mercury fish you eat, the higher your mercury is going be," Hightower warns.
Hightower who has published a study and written a book about the health effects of eating too much mercury says you need to choose the right fish. Swordfish and tuna can be high in mercury, while salmon usually has less.
Tarbox is part of an ongoing campaign by GotMercury.org to get people to eat less tuna. Why? They're on a mission to save the sea turtles that get caught in the commercial fishing lines used to catch tuna.
She bought one piece of tuna, swordfish and salmon at each store that carried all three types during a six-day period in April. She then had it tested by Micro Analytical systems, a California-based company specializing in mercury testing.
She says of the 23 samples tested, seven were above the FDA's guideline, which the government says is normal. The bigger the fish the more likely it has mercury.
"I tell people to buy a fish smaller than your plate," Hightower advises.
According to GotMercury.org, the fish with most mercury was swordfish from Ralphs on La Brea Avenue. According to the lab, it had a level of 3.06, and the FDA's limit is 1 part per million (ppm).
The fish with the second highest level of mercury was swordfish from Whole Foods at Third Street and Fairfax Avenue. It tested twice the federal level at 2.67 ppm.
Yet the salmon samples from the very same Ralphs and Whole Foods had very little mercury -- way below the federal limit at .015 ppm and .344 ppm.
Whole foods was the only market where we saw mercury warning signs in English and Spanish in the fish section. Whole Foods was also the only one with a consumer handout about mercury.
"The vast majority of commercial seafood has very low, and in some cases, undetectable amounts of mercury in them," argues Gavin Gibbons of the National Fisheries Institute, representing the fish industry.
"There is no demonstrable heath impact on the individual just because they had one piece of fish that slightly exceeds the FDA limit," said Gibbson.