Thanks, AMR. Good post. I'm not saying that if you go out and eat tuna you'll immediately get sick and die. I'm not saying that if you eat six cans a week, you'll get mercury poisoning. What I am saying is there is definitely mercury in tuna--and it's among the highest concentrations of mercury found in all fishes. This is something that we have to at least think about. After all, the tuna you eat becomes your body's biomass--mercury included. So, you're going to have mercury in your body. Mercury is very, very bad stuff, so I don't want any of it in my body. Over time, it will accumulate in your body, and this is directly proportional to the amount of mercury-containing foods you eat. I'd rather be on the safe side than sorry. No one knows the long-term effects of mercury--because this hasn't been an issue in our wildlife for an overly long time. But people do know the negative effects of mercury--they've known them for a long time. Have you ever heard the expression, "As mad as a hatter?" This is from the old hat makers who used mercury on the fabric--I think it was velvet--the mercury was a fixer. The hatters used mercury every day, and they got sick. In fact, they went crazy and lost control over their nervous system. Anyway, I don't want to argue this point anymore. Mercury is bad, and it's in tuna, so just be careful how much tuna you eat. And as far as the DDT goes, I used that as an example of how a "miracle" turned sour. I didn't want to start an fight over DDT. But DDT is bad stuff, and to anyone who thinks it's not is not properly informed. But I'm not going to debate that any further.