Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Mercury and Fish
Name: donna
Location: N/A
Country: N/A
Date: N/A


Question:
how does mercury get into fish in rivers. what is the ecological process involved which could produce toxic levels of mercury in fish and eventually get into humans?



Replies:
Hi Donna!

Nowadays mercury or its compounds are used at a high scale in many industries as the manufacture of chemicals, paints, household itens, pesticides and fungicides. These products can contaminate humans (and mamals) by direct contact, ingestion or inhalation. Besides the air can become contaminated also, and since mercury compounds produce harmful effects in body tissues and functions, that pollution is very dangerous.

Now for your question: Efluent wastes containing mercury in various forms sometimes are dropped in sea water or in rivers or lakes. There the mercury may be converted by bacteria, that are in the muddy sediments, into organic mercurial compounds particularly the highly toxic alkyl mercurials ( methyl and di-methyl mercury), which may in turn be concentrated by the fishes and other aquatic forms of life that are used as food by men. The fishes dont seem to be affected but they are able to concentrate mercury in high poisoning levels, and if human beings, mamals or birds eat these containing mercury fishes, algae, crabs or oysters they will be contaminated and poisoned.

By the middle of last century that danger was not quite known and some mass disaster killed many people poisoned by that way.

Hopefully now ecology has its turn and laws or recommendations all over the world prevents (or try to prevent) the careless disposition of these dangerous wastes.

Thanks for asking NEWTON!

Mabel
(Dr. Mabel Rodrigues)



Click here to return to the Biology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory