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Mercury In Our World
(Excerpted by permission from "Mercury:
Get Mad Now, Not Later," a 1994 fact sheet by the Western Lake Superior
Sanitary District)
 Mercury,
also known as quicksilver because it is a silver-colored liquid at room
temperature, is an element that does not break down. It occurs naturally
and is found in very small amounts in oceans, rocks and soils. It becomes
airborne when rocks erode, volcanoes erupt and soil decomposes. It then
circulates in the atmosphere and is redistributed throughout the environment.
(Click here for a listing of
the unique and interesting properties of mercury.)
Large amounts of mercury also become
airborne when coal, oil or natural gas are burned as fuel or mercury-containing
garbage is incinerated. Once in the air, mercury can fall to the ground
with rain and snow, landing on soils or water bodies, causing contamination.
Lakes and rivers are also contaminated
when there is a direct discharge of mercury-laden industrial waste or
municipal sewage. Once present in these water bodies, mercury accumulates
in fish and may ultimately reach the dinner table.
Although mercury has been a very useful
element, due to its unique properties, it poses a very real health risk-from
direct exposure to mercury, as well as from eating contaminated fish.
We can minimize this risk by reducing our use of mercury-containing products
and properly disposing of mercury-containing waste.
 Mercury
has been used for thousands of years for a wide variety of purposes. Historical
uses, which are no longer prevalent, include: preparing felt for hats,
controlling mildew in paints, killing weeds as a component of herbicides,
and various medical uses-teething powder, antiseptic ointments and syphilis
treatment. It's toxic effects on workers in hat factories in the late
1800's led to the term "mad as a hatter." Mercury is still used
for folk medicine and ceremonial purposes in several cultures.
Today, mercury is released to the environment
from many sources. It is used in household and commercial products, as
well as industrial processes. Coal-fired power plants, incinerators, some
manufacturing plants, hospitals, dental offices, schools and even homes
have all been found to release mercury. In the home, mercury can be found
in fluorescent lights, thermostats, thermometers, and even some children's
toys. At school, mercury may be in science and chemistry classrooms, the
nurse's office and electrical systems. School and home mercury audit activities
in this package provide more detailed information on where to find it
and what to do about it.
Mercury Health Issues 
Two different forms of mercury are of human health
concern. Elemental mercury, which is most toxic in its gas form, slowly
vaporizes at room temperature and more quickly when heated. Children playing
with elemental mercury can be seriously poisoned by breathing the invisible
vapor from mercury spilled in carpeting, furniture or other surfaces.
Elemental and inorganic mercury can
be transformed into organic mercury by the bacteria in the bottom mud
in water bodies. Unlike elemental mercury, organic mercury (often referred
to as "methylmercury") can be readily absorbed in humans. The
most likely source of methylmercury exposure is eating contaminated fish,
which can result in long-term damage to the kidney, liver and central
nervous system. Young children and developing fetuses are most at risk.
Organic mercury tends to increase up
the food chain, particularly in lakes. The mud at the bottom of a lake
may
have 100 or 1000 times the amount of mercury than is in the water. Worms
and insects in the mud extract and concentrate the organic mercury. Small
fish that eat these critters further concentrate the mercury in their
bodies. This concentration process, known as "bioaccumulation",
continues as larger fish eat smaller fish until the top predator fish
in the lake may have methylmercury levels in their tissues that are up
to 1,000,000 times the methylmercury level in the water in which they
live.
Most states advise anglers and their families to reduce their consumption
of certain types and sizes of fish either statewide or for individual
water bodies. Certain types of store bought fish also have elevated mercury
levels. The US Food and Drug Administration has issued consumption advisories
relating to mercury for mackerel, swordfish, tilefish, and tuna.
Mercury and Children's Health
The greatest risk of mercury poisoning is for fetuses
and young children because their nervous systems are still developing.
They are four or five times more sensitive to mercury than adults. Damage
occurring before birth or in infancy can cause a child to be late in beginning
to walk and talk, and may cause lifelong learning problems. Unborn children
can be seriously affected even though the methylmercury causes no symptoms
in their mothers.
Mercury Exposure from Cultural and Religious
Practices
In the United States, certain Afro-Caribbean and Latin
American traditions, including: Santeria, Palo, voodoo, and Espiritismo
incorporate the use of elemental mercury in folk medicine and religious
practice. Mercury is sold in most botanicas-stores specializing in herbal
remedies and religious items used in these traditions. Its use, normally
in small, enclosed spaces, combined with the fact that small amounts of
mercury can remain for long periods of time, create the potential for
very high direct exposures to individuals. Although these religious traditions
have been well studied by anthropologists and sociologists, and many medical
anthropologists have documented the use of potentially toxic remedies
in folk medicine, little attention has been focused on the health implications
of toxic substances used in religious rituals and spells.
Availability and extent of use
Several surveys have attempted to characterize mercury
use in Latino/a and Afro Caribbean communities. Metallic mercury is available
at botanicas in New York, New Jersey, and Pennsylvania, but botanica personnel
often deny having mercury for sale when approached by outsiders to these
religious and cultural traditions. Actions by public health authorities
have driven the mercury trade underground in some locations. In a survey
of New York City botanicas, 93% reported selling elemental mercury (about
one to four capsules per day). A survey of 115 botanicas in 13 cities
in the United States and Puerto Rico found that 99 sold mercury. Another
survey of 203 Caribbean and Latin American adults in the New York City
area found that 44% of Caribbean and 27% of Latin American respondents
reported using mercury.
Uses
Mercury is typically sold in capsules that contain,
on average, about 8 or 9 g (0.3 oz.) mercury. The most common method of
use reported by botanica personnel was to carry mercury on the person
in a sealed pouch (49%) or in a pocket (32%) as an amulet; sprinkling
mercury in the home was mentioned by 29%. Proprietors reported that family
members, friends, spiritualists, and card readers recommend mercury to
store patrons to bring luck in love, money, or health and to ward off
evil. A survey of Latin American and Caribbean New York residents found
that burning mercury in a candle, mixing it with perfume, and sprinkling
it in the car were also frequently reported uses. Of 28 New York botanicas
visited during another survey, 13 prescribed sprinkling mercury on the
floor. Mercury poisoning has also been documented in Mexican-American
infants fed mercury as a folk remedy for gastroenteritis. Medical anthropologist
Robert Trotter identified the use of mercury, as well as lead oxides,
for the treatment of empacho, a digestive illness.
Impact
As a result of these practices, living spaces may
become contaminated with mercury. Removal of elemental mercury from floorboards
and carpets is difficult, if not completely impractical. These mercury
practices can be a direct source of contamination not only in the users,
but also in their families, people living in adjacent apartments, and
any future residents of the premises. The potential liability to present
and future landlords is significant, because current and prospective homeowners
may raise concerns about health risks related to prior mercury use on
the premises. In addition, much of the mercury used in folk medicine and
religious practice may be disposed of improperly. One survey found that
64% of mercury users in a study reported throwing mercury in the garbage,
27% flushed it down the toilet, and 9% threw it outdoors. Preliminary
interviews with mercury users indicated a lack of knowledge about the
inhalation pathway as the primary route of mercury exposure. People seem
to know that mercury is toxic and avoid touching or eating it in most
cases, but they do not seem to know about how quickly it turns into vapor
(gas form) and the inhalation exposure risks associated with that. Several
local and national education efforts have been undertaken in the past.
Community involvement, outreach, and education
Because botanicas represent a critical link to health
care services in Latino/a and Afro Caribbean communities, it is important
to recognize the role of botanicas in providing culturally congruent health
interventions in their communities. Botanicas are the first place many
turn for general health care services in Latino/a and Caribbean communities;
any public health interventions to reduce mercury exposure must work with
spiritualists, Santeros, and botanica proprietors. Working cooperatively
with botanicas to promote effective substitutes and institute labeling
for mercury is more likely to be effective than an adversarial enforcement
approach that essentially criminalizes cultural practices. Outreach in
Afro-Caribbean and Latino/a communities is a must. Such outreach and education
will be most effective if they are coordinated with an effort to characterize
the ways mercury use and its hazards are understood in the communities,
so that communications can address any gaps in knowledge and provide the
most important information to mercury users.
*Previous information taken from "Assessing Elemental
Mercury Vapor Exposure from Cultural and Religious Practices," by
Donna M. Riley, C. Alison Newby, Tomas O. Leal-Almeraz, Valerie M. Thomas-article
published in Environmental Health Perspectives - Volume 109, Number 8,
August 2001
July 4, 2001 Posted: 5:51 AM EDT
Thai diners told steer clear of 'toxic' shark fin
BANGKOK, Thailand - The health ministry in Thailand
is urging diners to stay away from shark fin soup following reports that
the increasingly popular delicacy may contain dangerously high levels
of mercury.
On Tuesday a report by environmental pressure group Wild
Aid said shark fins found on sale in Thailand contained levels of the
heavy metal as much as 42 times the level considered safe for human consumption.
Responding to the report, Deputy Public Health Minister Surapong Suebwonglee
told Thai television Wednesday that officials were collecting samples
of the soup from various restaurants and would be conducting tests over
the coming days. He said that until safety tests had been completed diners
should avoid eating the dish. Pressure groups have been calling for a
halt to the growing trade in shark fins across Asia which they say is
cruel, wasteful and having a devastating effect on the shark population.
Shark fin soup has been growing in popularity across East Asia where,
because of its high price, it is considered a prestigious dish to order
at business occasions, weddings and other banquets.
Soaring demand
In Hong Kong, a world center for the shark fin trade,
a single bowl of soup can cost more than US$100. To feed this demand environmentalists
say millions of sharks are killed each year for the fin trade, most of
them taken from waters in the Asia-Pacific region. Wild Aid says that
between 1980 and 1997 trade in shark fins more than doubled to 7,000 tons
annually. The majority of the sharks are pulled from the sea, have their
fins hacked off, and are then thrown back into the water where -- unable
to swim without their fins -- they drown. Environmentalists say sharks
perform a vital function at the head of the food chain and dwindling shark
populations will have a serious effect on the marine eco-system.
Bulked out
In conducting its survey Wild Aid said it had tested
samples from 10 fins bought from three dealers in Bangkok's Chinatown.
It said all contained dangerously high levels of mercury and were also
pumped full of as yet unidentified chemicals. The report said that the
need to bulk out fins in this way was a further sign that the shark numbers
were decreasing. News that fins may contain dangerously high levels of
toxins is being seen as adding further weight to environmentalists' campaigns
to stem the trade. Already pressure from such groups had persuaded a number
of Asian airlines to stop serving the soup to their business and first
class passengers, and last year Taiwanese officials vowed to ban dishes
made with shark fins from official banquets. In any case, campaigners
say, the fins contain no nutritional value and have little themselves
in the way of taste. They say that basically what diners are eating is
cartilage, the same material that makes up fingernails or hair.
Even though they are considered a prestigious dish, shark
fin consumption pose threat to consumers and to shark population.
*previous article taken from cnn.com
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