24/03/2005 - Professor
Paul Galand is a lifelong scientist, biologist
and TV commentator. His research into oestrogen
action and disruption has shown him why we
should apply the ‘precautionary principle’
to control potentially harmful chemicals and
the importance of REACH.
Professor Galand first became interested
in oestrogen disruption when he saw how DDT
acted as a prolonged estrogen on rats. He
noted that a single exposure to DDT kept stimulating
the rat’s hormonal system over time, as if
normal estrogens were being administered repeatedly.
This never happens in normal physiology, so
indicated that estrogen disrupting chemicals
could block oestrogen action or mimic it at
inappropriate times.
He explained that there was nothing in a
chemical’s structure which made it possible
to predict whether it would disrupt the female
reproductive system. The only indication is
that it reacts with the oestrogen receptor.
"It is like a lock and key, the hormone
being the key, the lock the receptor,"
he said.
"The disruptor may enter the lock (i.e.
bind to the receptor) and either open or block
it. So it will either mimic the chemical reaction,
but at an inappropriate time, or inhibit estrogenic
stimulation."
Estrogen disruption – the emerging part of
the iceberg
Professor Galand’s explanations give an idea
of the horrifying scale on which chemical
compounds could be inflicting harm to our
endocrine (i.e. hormone regulated) physiology.
"The easiest way to detect the negative
effects of chemicals, apart from direct toxicity,
is to look at how reproduction is being affected,"
he said. "Since most of the functions
selected by evolution were based on reproductive
success, any change in an organism’s physiology
is likely to affect reproduction."
Hence his conclusion that oestrogen disruption
might be the "emerging part of the iceberg"
represented by other hormones (like male,
thyroid or glucocorticoid hormones) and their
respective target tissues system which were
likely to exhibit similar disrupting chemical
effects.
"There is no reason to expect that the
oestrogen dependent physiology would only
be affected directly," said Galand. "These
effects point to far greater dangers lurking
beneath."
He explained that when animal and human foetuses
are exposed to oestrogen or oestrogen-like
compounds this may result in increased genital
abnormalities or even tumours as adults, while
having no evident effect on the mother. This
makes it even more difficult to predict a
compound’s "endocrine disrupting"
potential.
"The difficulty in predicting endocrine
disruptor potency may be counter-balanced
by observing animals, particularly wild animals
which are exposed in their environment,"
Galand explained.
"As animals have many points in common
with humans at a physiological level one should
take epidemiological information gained in
the wild into account — the so-called "wildlife
connection".
Applying the precautionary principle to hazardous
chemicals
Professor Galand specializes in oncology.
So, does he agree with those who blame chemicals
for the rising cancer rates?
As a scientist he is understandably cautious.
However, he believes that the precautionary
principle should be applied if there is enough
epidemiological data (from wildlife or those
exposed professionally) to show that increasing
cancer rates could be associated with chemical
exposure.
Does he believe that all chemicals are dangerous?
He explained that there had always been harmful
substances which some living organisms could
not "adapt" to, while the resistant
("adapted") mutants survived.
"Antibiotics or pesticides do not produce
resistant bacteria or mosquitoes," he
said. "They select the pre-existing one
among the respective populations."
Today, artificial chemicals are being produced
at such a rate that most organisms cannot
reproduce fast enough - i.e. their generation
time is too long - to make such selection
possible. This is another reason for applying
the precautionary principle.
REACH ‘nearly perfect’ – if properly applied
Galand believes that REACH could help control
disruptors better. He described it as being
"nearly perfect’…provided it is properly
applied. This means publishing adequate legal
indications or instructions on its application.
"REACH could be applied properly if we
used laws that punished companies financially
very severely when they broke the law. We
should come down heavily on companies which
deliberately neglect the negative findings
of research, be it their own or that which
they have subsidised".
He is also heartened by the Belgian government’s
support for REACH.
"We should support the Belgian stand
for REACH, which is an important first step
for controlling harmful chemicals," he
said. "Improvements may be brought in
later, based on the experience gained. But
let us launch it."
‘God’s Justice’
Now that steps have been taken to control
the production and use of some of the known
hazardous chemicals such as DDT and PCBs,
was Galand optimistic that the dangers associated
to them have diminished? Not at all.
"Don’t think because these chemicals
were banned in Europe you’ve got rid of them,"
he warned.
"They not only persist in the environment,
but are still sold and used in countries outside
Europe and are carried through the atmosphere
to arrive back here. There is also a kind
of "God's justice" in the fact that
we find them in the fruits we buy from those
countries."
He also had views on how chemical companies
should apply the ‘benefits and costs’ arguments.
"They should take the long term costs
into account," he said. "We have
already seen some companies, like the tobacco
companies, having to pay out where they have
been proved to have caused damage. Tobacco’s
effects were known, yet the companies neglected
them."
So chemical companies should include the
effects on the environment in calculating
their costs-to-benefits ratio.
He referred to the ‘social benefit’ position
frequently taken by the chemical industry.
What are the social long-term benefits of
overburdening the environment?
"We might at least stop the production
of artificially produced compounds that we
don't need and which, besides their short
or long term toxicity, create a series of
environmental — and costly — problems. A good
example of this is the "over-packaging"
in plastic polymers. In speaking of "social
benefit" one should always be clear about
whom is actually benefiting," he finished.
