General Question

silky1's avatar

The mercury in fish where exactly does it come from?

Asked by silky1 (1500 points ) September 5th, 2010

I was wondering is their a lot of mercury already in fish or does the environment play a big part?

Observing members: 0 Composing members: 0

6 Answers

gorillapaws's avatar

I know it accumulates in bottom feeders (such as shellfish) and also larger species, because they eat lots of smaller fish (each with a little bit of mercury) so it builds up in their systems overtime.

jaytkay's avatar

The ocean absorbs human and natural emissions of mercury, and as @gorillapaws points out, the little creatures ingest it in the water and the big ones get a concentrated dose from eating little ones.

Coal-fired power plants produce a lot. And volcanoes, too, but they are not running 24/7.

Here is an excellent graphic showing emissions over time by source. It’s interesting how the California Gold Rush spiked the graph, from the use of mercury in gold refining.
Also notice the sharp drop-off in recent years.
http://toxics.usgs.gov/pubs/FS-051-02/images/fig3.gif

More explanation here:
http://toxics.usgs.gov/pubs/FS-051-02/

marinelife's avatar

“These continental to global scale occurrences of mercury contamination cannot be linked to individual emissions of mercury, but instead are due to widespread air pollution. ”

U.S. Government

Ben_Dover's avatar

It comes from…people!

OwlofHappiness's avatar

It comes frome the water they swim in.

Linda_Owl's avatar

The mercury comes from industrial waste that gets released into the air & dumped in our rivers, lakes, & oceans. A small fraction is naturally occurring, but basically it comes from thoughtless/unconcerned & deliberate greedy human pollution of our environment.

Answer this question

Login

or

Join

to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
or
Knowledge Networking @ Fluther