ROBBIE -  I received this on a bulletin board.  It may be of interest to
subscribers in light of the recent discussions on safety and mercury.
Please edit as necessary.  If this submission strays too far off the
topic of automatic music machines and safety, please return it to me.

Thanks for helping Jody with the monumental editing task!

Joyce Brite

 [ Editor's Note:
 [
 [ Thanks for the words of support to Robbie.  He lends a
 [ fresh perspective to the editing and gives me a chance
 [ to cope with other obligations (including the upcoming
 [ MBSI convention, setting up a Web page, taking my 5 year
 [ old son to organ concerts, etc...
 [
 [ I'm posting the remaining portion of your message
 [ without further editing.  I found it quite interesting.
 [
 [ Jody

---------- Forwarded message ----------

PERSPECTIVES ON THE FOURTH INTERNATIONAL CONFERENCE ON MERCURY AS
A GLOBAL POLLUTANT, Hamburg, Germany, August 4-9, 1996

James Wiener and Teresa Naimo (Upper Mississippi Science Center,
La Crosse, Wisconsin) recently attended the Fourth International
Conference on Mercury as a Global Pollutant.  This report
summarizes their perspectives on the mercury conference and on the
state-of-the-science in the ecotoxicology of mercury in the
environment.

This excellent international conference was attended by a diverse
disciplinary array of scientists studying the biogeochemistry,
sources, environmental transport, bioaccumulation, and
ecotoxicological effects of mercury in the environment.  The
conference attracted more than 400 scientists from 30 countries,
and much of the information presented at the conference was
directly relevant to research initiatives being jointly explored
by the USGS and NBS.

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Mercury Pollution in Historic Perspective:

Mercury (Hg) is a toxic metal with no known essential function in
living organisms.  The severe consequences of mercury
contamination of aquatic food chains were first recognized in the
1950s and 1960s in Minamata and Niigata, Japan, where human
consumers of methylmercury-contaminated fish were severely
poisoned (many died).  In the 1960s, humans and birds consuming
seed grain treated with alkylmercury fungicides were also
poisoned.  These tragedies prompted widespread reductions in
point-source discharges of mercury into surface waters and in the
agricultural use of alkylmercury fungicides.  Concentrations of
methylmercury declined in fishes inhabiting mercury-polluted
surface waters after point-source discharges of mercury were
reduced, although concentrations in fish have remained
unacceptably high in some waters.

In the past decade, high concentrations of mercury have been found
in fish from low-alkalinity and humic lakes, newly flooded
reservoirs, and wetland ecosystems.  These findings have renewed
public concern about environmental mercury in many developed
countries.  In the United States, many state health and fishery
management agencies have responded to the current fish-mercury
problem by issuing advice concerning consumption of sport fishes.
Many developing countries are now experiencing problems with
mercury pollution as the result of releases from gold-mining areas
and certain industrial operations.

Methylmercury is neurotoxic, damaging the central nervous system.
To date, societal concern about mercury in aquatic ecosystems has
stemmed largely from the potential adverse health effects of
consuming methylmercury-contaminated fish, because human exposure
to methylmercury is almost wholly due to fish consumption.

Adverse Biotic Effects and Information Gaps:

Our understanding of the biogeochemistry of mercury remains far
from complete.  In the last decade, however, applications of new
methods for contamination-free sampling and ultra-trace analysis
of air, rain, and water have shown that seemingly small amounts or
inputs of mercury can cause significant contamination of fishes in
certain ecosystems.  In fact, many of the freshwater ecosystems
with recent fish-consumption advisories seem to be lightly
contaminated environments in which inorganic divalent mercury is
readily converted to methylmercury, the neurotoxic form
accumulated in fish.  This certainly seems to be the case in the
South-Florida Everglades, an ecosystem being studied by state,
private-sector, academic, and federal scientists, including a
multi-disciplinary team led by David Krabbenhoft (USGS, Madison,
Wisconsin) with funding from the USGS Ecosystem Program.  It is
also evident that some human activities, such as construction of
new reservoirs, increase mercury levels in fish largely by
creating environmental conditions that enhance the microbial
production of methylmercury.  The scientific challenge is to
identify and understand the processes and interactions that
enhance the production, bioaccumulation, and trophic transfer of
methylmercury in such ecosystems.

Ongoing investigations by wildlife toxicologists--studies that
were decidedly under-represented at this international
conference--strongly suggest that methylmercury contamination of
aquatic food webs in certain ecosystems is adversely affecting
fish-eating wildlife, such as loons, wading birds, mink, and
otters.  Evidence suggesting a link between methylmercury exposure
and adverse reproductive effects in fish-eating wildlife was
recently examined at a workshop on mercury in wildlife, convened
in April 1996 in Fairfax, Virginia.  (The workshop was organized
by Douglas Knauer and Mike Meyer of the Wisconsin Department of
Natural Resources, and was co-sponsored by the Electric Power
Research Institute and the Wisconsin Department of Natural
Resources.)  The embryos of vertebrate organisms are highly
sensitive to methylmercury.  In mammals, all prenatal effects of
methylmercury poisoning seem to be irreversible, because they
involve developing neural pathways.  The effects of methylmercury
on birds are much more severe in embryos and chicks than in
adults, and low-level dietary exposures that cause no measurable
effect in adult birds can significantly impair egg fertility,
hatchling survival, and overall reproductive success.  The dietary
concentrations of methylmercury needed to significantly impair
reproduction in birds are only one-fifth of those that produce
overt toxicity in the adult.

Concerns about piscivorous (fish-eating) wildlife could greatly
influence future actions and perspectives on the mercury issue.
The National Biological Service (soon to be the USGS Biological
Resources Division) could contribute greatly to improving
scientific understanding of the ecotoxicological consequences of
methylmercury contamination of aquatic food chains for upper
trophic levels.

Prepared by James G. Wiener and Teresa J. Naimo; August 19, 1996

   United States Department of the Interior
   National Biological Service
   Upper Mississippi Science Center
   2630 Fanta Reed Road, P.O. Box 818
   La Crosse, Wisconsin 54602-0818

   phone 608-783-6451; fax 608-783-6066
   james_wiener@nbs.gov
   teresa_naimo@nbs.gov