Some health experts say eating fish can be dangerous to your health because of the high mercury levels found in certain species. Others say the health benefits of fish outweigh the hazards. VOA's Paige Kollock reports on a new way consumers can decide for themselves.
Fish are full of vitamins, and are rich in Omega-3 fatty acids. Omega-3 acids help reduce inflammation, prevent blood clots and encourage rhythmic heartbeats, all of which reduce the chance of heart attack and increase cognitive activity in the brain.
But according to reports from the U.S. government and some environmental groups, certain fish contain high levels of mercury, a toxic element that can cause brain damage, especially to fetuses.
Consumers have been confused by conflicting reports about the safety of fish.
Charles Santerre, a food toxicologist at Purdue University in Indiana, analyzed over 250 cans of tuna, salmon, and mackerel for mercury.
"There are types of tuna, and for us it was chunk light tuna in water, that had extremely low levels of mercury,” he told us. “So we would recommend that these be eaten by pregnant women, nursing women, young children."
Until now, that was about the only way to tell how much mercury is in the fish you buy, but new technology is changing that.
Malcolm Wittenberg works for a California company called MicroAnalytical Systems. It is introducing machines that can test mercury levels.
"They will tell consumers what the average mercury level is for a particular species, and what the actually level is for this particular tested product," said Mr. Wittenburg.
He says mercury levels can vary widely. "You could, for example, have one piece of tuna which would have 300 times the mercury content of another piece of tuna." He hopes to use the machine to create labels for store-bought fish.
Dr. Jane Hightower, who has studied mercury levels in fish extensively, says the testing machine is a great tool because it gives consumers more information.
"Now you can test for the mercury content, and people at least will know what they're getting and it won't be a roulette game."
The U.S. Food and Drug Administration thinks labeling might scare consumers away.
Moms, like Joan Davis, like the idea of labeling. Her 12-year-old son Matthew used to eat fish every day before he was diagnosed with high mercury levels in his blood. As a result, he began suffering in school.
"He was having trouble forming sentences and doing writing work," said Matthew’s mom.
Matthew's health eventually improved. So far, one small California grocery chain has agreed to use the machines to test for mercury.