Why mercury is so high in seafood but not land meat


I’m not really educated on this, but as my mercury is now high, I am trying to learn all I can about it.

Does anybody know the reason for this?

Why does the pollution in the ground and from the rain not seem to get into the grass and veggies the animals eat as much as it gets into the fish?


One reason is that fish eat fish who eat fish who eat fish. So, fish higher on the food chain (swordfish, shark, etc.) have more metals than those lower on it (sardines etc.) as they end up getting concentrated heavy metals through that pathway.



Good question. It’s not exactly water soluble, so how is the uptake less on land rather than at sea?
Is it air dispersal after incineration of waste, then precipitation into the sea? I don’t know.

It will form compounds, and no doubt form easier bioavailable routes into certain parts of the aquatic food chain. And build up.

Fish can’t escape the ocean, that’s their environment.
Pretty much like we can’t escape the atmosphere.

I would suggest that it might be because mercury pollution is going directly to the sea rather than land areas…or at least leaching from land dumps into the sea. Or through precipitation.

It’s nothing I know much about- apart from avoiding eating too much of the fish that can accumulate too much mercury.


Yet snow crab appears to be higher in mercury than chinook (a big salmon). Perhaps because they live much longer than salmon? 've been eating the lower mercury seafood from Alaska only but the mercury level has not gone down.

(Eric) #5

From what I read, the mercury in streams and oceans is converted to methylmercury by microorganisms. Then the fish absorb that via their gills and the food they eat (ie. other fish).


The ground is literally a filter, the way sand, gravel and rocks work is what we emulate when we build water filters. The ocean isn’t, and waste water, industrial crap and storm water that’s contaminated winds up back in the oceans at some point.

Pretty impossible to beat high Mercury levels with fish being a main protein source. Even if you buy farmed fish then arsenic is an issue along with them being fed a BS diet.

Was your metals test a hair one by chance?


Don’t and won’t eat farmed fish. I was eating a lot of canned pacific mackerel for a couple months. I stopped that. l only eat seafood from Alaska now, and never canned. The taste of the can was bothering me and I think some B vitamins and A are lost in the heating.

It was a blood test. After eating mostly pacific mackerel it was 19.5ug/L. A month later after switching to only Alaskan salmon and snow crab it was 21ug/L. I ordered a hair test yesterday. Maybe it’s just a small discrepancy and has really just stayed the same and will take time to come down? That is what I am really hoping for…I have a feeling not likely. Perhaps should stop the crab. A lot of sites list it as .09. Chinook .06 mercury .02 for sockeye. I have depression, anxiety, nervousness, and eye issues right now and I’m wondering if its the mercury. There was a time I ate just salmon and I don’t remember feeling bad.

I also can’t figure out what is a truly dangerous mercury level in the blood. Supposedly you should be under or = to 7-10ish ug/L but is 20 really bad? I can’t tell from what I’ve read.


What you have said above, about canned fish, is probably not helping your anxiety levels, and probably uneccessary.

However, I live in North UK and our mackerel is fine, more than fine, and I would eat it for breakfast twice a week (if I can remember to get past the eggs).

Maybe just switch to a different source of what you need/ or supplements even, if it’s adding to anxiety.

Try not to worry mate.


I think this answers it, and yes, the lower on the food chain you eat the less mercury you will intake. I avoid farm raised fish of all kinds.

Never had a mercury test, but also never had any symptoms that I had too much. I eat fish at least twice a week, often more than that. Primarily, wild salmon, tuna, and sardines, but mahi mahi if I can get it, it isn’t always available here.