Naked Science Forum

Life Sciences => The Environment => Topic started by: Karen W. on 10/02/2008 15:24:43

Title: How long is the Mercury in our oceans going to remain dangerous ?
Post by: Karen W. on 10/02/2008 15:24:43

Well With all the warnings about tuna and other seafood containing

too much Mercury, I just wonder you know? Just when or how long if

ever will it be before levels become safe?

Title: How long is the Mercury in our oceans going to remain dangerous ?
Post by: another_someone on 12/02/2008 20:08:35

Who says levels are not safe?  What are 'safe' levels?

We have always had mercury in the sea (humans have never created any mercury, all they have don is purified what was already there, so when they put it back in the environment from whence they took it, it is still the same mercury).

The problem with tuna fish is that they are at, or near, the top of the food chain, and this combined with their large body size, and long life span, means they tend concentrate heavy metals that exists in smaller concentrations in the fish they eat, which itself concentrates the heavy metals in whatever food they take in.

We simply do not know at this time if levels of mercury we see in tuna fish is a modern phenomenon, or was always there.  At this time, it is just as possible that tuna fish caught hundreds, or thousands, of years ago also had higher levels of mercury; but not necessarily unsafe levels of mercury (depending on exactly how much tuna you eat).

Title: How long is the Mercury in our oceans going to remain dangerous ?
Post by: Karen W. on 13/02/2008 02:33:44

My husband says "Excellent that is just what I wanted to know." I liked that anwer very much." I should have said this was his question.