How "toxic" are we?
WWF carried out a survey last year in which 155 volunteers had their blood
analyzed for over 70 man-made chemicals. The results are disturbing. One of the
volunteers, for example, was shocked to discover that her body is contaminated
with at least 30 man-made chemicals — including several that were banned when
she was still a child.
Jamie Grant
Thousands of man-made chemicals have been developed over the last several
decades — chemicals to control disease, increase food production, and provide
convenience for day-to-day living. But ironically, many of these
well-intentioned chemicals are threatening wildlife and people with the very
qualities that make them useful: toxicity and stability.
PCB's
"PCBs, or polychlorinated biphenyls, are one example of these
chemicals," says Dr Michael Warhurst, Senior Toxics Officer at WWF.
"From the 1950s onwards they were widely used in many different items, from
electrical transformers to paints and adhesives. Originally they were thought to
be safe. But then evidence began to mount that not only was wildlife
contaminated with PCBs, but that they were toxic."
PCBs are now ubiquitous in the environment. Everything from the soil and
water to fish, polar bears, and water birds are contaminated with them. They've
been blamed for the widespread declines of mink, otter, and other species in
North America and western Europe, as well as deaths of seals in northern Europe.
In humans, exposure has been linked to a number of problems, including a
negative impact on the neurological development and mental ability of children.
Their legacy continues. The use of PCBs has been gradually phased out around
the world since the 1970s. Yet all of the 155 people who had their blood tested
in WWF's recent survey in the UK had PCBs in their blood.
But PCBs aren't the only worrying chemical. Altogether, some 300 man-made
chemicals have been found in humans and wildlife. Many of these are used in
common consumer products. And while their effects on human and animal health are
largely unknown, evidence is mounting that they cause a number of serious health
problems — including cancer, damage to the immune system, behavioural
problems, and reduced fertility.
Stable chemicals
So how have these chemicals ended up in so many people and different animals?
"These chemicals are very stable, and they can accumulate in the body
fat of animals," explains Dr Warhurst. "They can escape into water,
soil, and air during their manufacture, use, or disposal, as well as from
accidental leaks or fires in products containing these chemicals. Once in the
environment, they can travel for long distances in air and water."
Tiny animals at the bottom of the food chain, such as plankton in the oceans,
absorb the chemicals as they feed. Because they do not break down easily, the
chemicals accumulate in these organisms, becoming much more concentrated in
their bodies than in the surrounding water or soil. These organisms are eaten by
small animals, and the concentration rises again. These animals are in turn
eaten by larger animals, which can travel large distances with their even
further increased chemical load.
Animals higher up the food chain, such as seals, can have contamination
levels millions of times higher than the water in which they live. And polar
bears, which feed on seals, can have contamination levels up to 3 billion times
higher than their environment.
People become contaminated either directly from household products or by
eating contaminated seafood and animal fats.
Breast milk
What's more, mammals, including humans, can pass these chemicals onto their
babies during pregnancy and via mother's milk. This means that these chemicals
can continue to contaminate people and wildlife for generations.
"Women have been found to have lower levels of certain man-made
chemicals than men, and the levels appear to go down in relation to the number
of children they have had," says Dr Warhurst. "These differences may
be related to women ‘off-loading’ some of the chemicals in their bodies to
their children."
Experts agree that breast milk is still best for a baby and brings
substantial benefits. The biggest problem for a child seems to come from
exposure to chemicals while it is developing in the womb.
"In-womb exposures to chemicals may be linked to birth defects in the
genitals of baby boys and low sperm counts and testicular cancer in later
life," says Dr Warhurst.
Industrial chemicals
But how is it that our planet is so contaminated with these chemicals?
"A big part of the problem is that there is no good regulatory system
for industrial chemicals," says Dr Warhurst. "The normal approach is
one of 'innocent until proven guilty'. A chemical can be developed and widely
used without undergoing strict safety tests. Only once it's shown to contaminate
people and wildlife and cause health problems will it be restricted or banned.
This can take years, even decades."
Brominated flame retardants are an example of a group of chemicals in
widespread use that may one day be linked to health problems. Used in fabrics
and TVs, they've been found in sperm whales, seals, and the eggs of peregrine
falcons. They're also found in the breast milk of mothers in Europe and North
America.
""There is not a single animal or person on the planet that has not
been exposed to man-made chemicals, most of which lack basic safety
information," says Dr Warhurst. "We are all guinea pigs in a massive
global experiment. It needs to be stopped."
This is why WWF is working to ensure that a new law proposed in the European
Union (EU) will properly regulate chemicals and phase out the most dangerous
ones. The chemicals of principal concern to WWF include those that are very
persistent and that accumulate in animal and human bodies, as well as those that
disrupt hormone systems.
"The proposed EU law, called REACH, offers a chance to identify and
phase out the worst chemicals," says Dr Warhurst. "New markets for
safer products, and increased trust, should make it good news for the chemical
industry too. And the new law will help tackle the toxic threat not just in
Europe, but around the world."
More information:
WWF - www.panda.org
* * Jamie Grant was formerly Press Officer at WWF Scotland, and is now a
freelance writer based in Scotland.
Reproduced with permission from WWF. © 2002 WWF-- World Wide Fund For
Nature. (Formerly World Wildlife Fund). All rights reserved.
- Chemicals in breast milk
Although scientists have found man-made chemicals in breast milk, it is
important to note that experts agree that breast milk is still best for a baby
and brings substantial benefits. Research indicates that the biggest problem for
a child comes from exposure to chemicals when it is developing in the womb,
rather than from breast milk.
- WWF also took blood samples from 40 members of the European Parliament in
December 2003. The results are expected to be released in April this year.
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