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Hormones in the environment: how the facts were covered up
By Paul Mitchell
20 September 2000
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Every male fish in some European rivers shows pronounced female
characteristics, according to Professor Alan Pickering of the
Natural Environment Research Council. Speaking to the British
Association's Festival of Science in London earlier this month,
Pickering said, "We are finding this problem right across
northern Europe, it is clearly widespread."
Pickering said that "It seems to relate to a mixture of
chemicals both industrial and also some of the natural excretory
products from the human body." These substances, known as
endocrine disrupting chemicals (EDCs) or gender-benders,
are found in some agrochemicals, paints, oils, toiletry products
and detergents. They mimic the hormones produced by the female
ovaries and the male testes in animals, which regulate growth
and reproduction.
The evidence that they affect human health is conflicting and
controversial. According to a report by the Royal Society in June
2000, Humans are exposed daily to environmental chemicals
which have potential endocrine disrupting activity, raising concerns,
provided that the level of exposure is sufficient, that such chemicals
might be linked with phenomena such as declining sperm count in
the adult male, testicular cancer, breast cancer, age at puberty,
etc. The incidence of testicular cancer, for example, has
increased three-fold in the last thirty years in Britain, becoming
the commonest cancer in young men.
However, the situation is complex, also involving genetic and
dietary factors. Breast cancer in China and Japan is much lower
than in Western countries. Scientists think this could be linked
to a high-fibre, low fat diet, and yet there is high consumption
of soya in these countries, which produces weak EDCs.
Because humans produce hormones in their bodies naturally,
the effects of EDCs are difficult to unravel. But it is thought
possible that the foetus, which is naturally protected from the
high levels of hormones in its pregnant mother, could still be
affected.
Chemicals that are now known to be EDCs were first manufactured
in the 1930s. In 1938 researchers showed that medicines containing
them could cause reproductive changes. In the 1950s and 60s, a
synthetic female hormone, diethylstilbesrol, given to prevent
miscarriages increased vaginal abnormalities in mothers and reduced
fertility in some of the six million babies that were exposed
to it.
Evidence of similar effects in the environment was developing.
Pesticides such as DDT caused reproductive problems in animals
and paints used on ships to prevent the growth of barnacles led
to shellfish sterility.
In England, the government-run Water Research Centre published
a report called Steroids as Water Pollutants in 1976. (Steroids
include the female hormone oestrogen and its male counterpart
testosterone, as well as hormones produced by the adrenal gland.)
At about the same time abnormal fish were noticed in rivers
in southern England downstream of sewage works. Scientists first
thought pharmaceutical factory wastes discharging into the sewers
were the cause. Research into the abnormalities was carried out
in 1981 by Liverpool University, commissioned by the then state-owned
water authorities. It was never published because they claimed
the research was flawed.
The Ministry of Agriculture carried out a further investigation
in 1988 that showed all sewage treatment works effluents
were oestrogenic to fish and whatever chemical, or mixture of
chemicals was causing the effects, it was ubiquitous. It
was suggested that natural and synthetic oestrogens were the cause.
The Conservative government kept these potentially explosive discoveries
confidentialthey were in the middle of privatising the water
industry until 1992. Even then the research was only published
in a magazine produced by the Foundation for Water Research that
had a restricted circulation within government departments and
the water industry.
A further one-off study was commissioned by the government
to look at river water used in the public water supply. It concluded
there was insufficient evidence to justify general regulatory
action, other than further research. It appears that the
EDCs in sewage break down in the river or are destroyed in the
water treatment works.
This research was also intended to be confidential, but in
1993 specialist magazines, then newspapers and the BBC's Countryfile
program had picked up the Foundation for Water Research report.
The BBC program Horizon later that year brought the issue
to wider public attention. It accused the water companies and
government of a cover-up. It quoted a water company spokesman
who said, There is no need and no requirement in the United
Kingdom Water Quality Regulations to look for these substances.
Nor are sufficiently sensitive techniques available. Hence routine
monitoring has not been carried out.
Although the regulations say the companies should monitor for
a few dozen specific substances, they also say the companies should
monitor for any other substance that could be injurious to public
health. It is likely the companies have monitored for hormones
in the public water supply, despite the difficulties of analysis.
The results have never been made public, even though the companies
say the treatment process destroys hormones and the water is safe.
(One might ask, if the methods used to analyse hormones were suspect,
how could the companies say the water was safe?)
This year the Labour government has updated the Regulations
in line with revised European legislation, but EDCs are not mentioned
specifically. How much of this was due to lobbying by the powerful
water industry group EUREAU is uncertain.
In the meantime, Britain's water companies have other problems.
They have carried out a large program of water pipe renewal. To
cut costs existing pipes have been lined inside with plastic rather
than being dug up and replaced. This involved the use of epoxy
resins containing bisphenol-A, another EDC, to harden the plastic.
In 1995, Welsh Water was prosecuted for not checking the resins
had set before using the renovated pipe work for drinking water.
Despite this evidence and an Environment Agency report in 1997
that enzymes in sewage re-activated hormones normally excreted
by humans in an inactive form, the government said the following
year that it had made no estimates of cost of removal since
the impacts are unclear.
Recent scientific evidence confirms the suggestion made in
1988 that two natural human hormones and one synthetic contraceptive
hormone are the likely EDCs in sewage works' discharges. On the
River Aire in Yorkshire it is chemical rather than human substances
that are responsiblean industrial detergent used for cleaning
wool in the remaining mills along this waterway.
It is clear that the British government and the water companies
have worked together to minimise the impact of the revelations.
The House of Lords also criticised water companies for doing the
bare minimum of research into water safety compared to the huge
profits they have made since privatisation. The situation has
been further complicated by the confidentiality surrounding the
precise chemical formulae of many industrial products.
Vital time has been lost in the scientific resolution of this
complex environmental problem. The Royal Society recommended in
its June 2000 report that the effects of endocrine chemicals
released into the environment should be further investigated
and that regulations cannot be put on hold' until
all the evidence has been collected. Twenty five years after
the first abnormal fish were discovered in Britain's rivers, the
report notes that, Few, if any, studies have attempted to
look for such evidence affecting human health and there
has been no guidelines on testing pharmaceuticals for environmental
impact, despite the fact that these chemicals are designed to
be extremely potent and to degrade slowly.
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