Pollutants cause huge rise in brain diseases
Scientists alarmed as number of cases triples in 20 years
by Juliette Jowit, environment editor
Sunday August 15, 2004
The ObserverThe numbers of sufferers of brain diseases, including
Alzheimer\'s, Parkinson\'s and motor neurone disease, have soared across the
West in less
than 20 years, scientists have discovered.
The alarming rise, which includes figures showing rates of dementia have
trebled in men, has been linked to rises in levels of pesticides, industrial
effluents, domestic waste, car exhausts and other pollutants, says a report
journal Public Health.
In the late 1970s, there were around 3,000 deaths a year from these
conditions in England and Wales. By the late 1990s, there were 10,000.
\'This has really scared me,\' said Professor Colin Pritchard of Bournemouth
University, one of the report\'s authors. \'These are nasty diseases: people are
getting more of them and they are starting earlier. We have to look at the
environment and ask ourselves what we are doing.\'
The report, which Pritchard wrote with colleagues at Southampton University,
covered the incidence of brain diseases in the UK, US, Japan, Australia,
Canada, France, Germany, Italy, Netherlands and Spain in 1979-1997. The
researchers then compared death rates for the first three years of the
study period with
the last three, and discovered that dementias - mainly Alzheimer\'s, but
including other forms of senility - more than trebled for men and rose
per cent among women in England and Wales. All the other countries were also
For other ailments, such as Parkinson\'s and motor neurone disease, the group
found there had been a rise of about 50 per cent in cases for both men and
women in every country except Japan. The increases in neurological deaths
rises in cancer rates in the West.
The team stresses that its figures take account of the fact that people are
living longer and it has also made allowances for the fact that diagnoses of
such ailments have improved. It is comparing death rates, not numbers of
As to the cause of this disturbing rise, Pritchard said genetic causes could
be ruled out because any changes to DNA would take hundreds of years to take
effect. \'It must be the environment,\' he said.
The causes were most likely to be chemicals, from car pollution to
pesticides on crops and industrial chemicals used in almost every aspect of
life, from processed food to packaging, from electrical goods to sofa covers,
Food is also a major concern because it provides the most obvious
explanation for the exclusion of Japan from many of these trends. Only when
people move to the other countries do their disease rates increase.
\'There\'s no one single cause ... and most of the time we have no studies on
all the multiple interactions of the combinations on the environment. I can
only say there have been these major changes [in deaths]: it is suggested it\'s
Pritchard\'s paper has been published amid growing fears about the chemical
build-up in the environment. A number of studies have pointed to serious
problems. TBT is being banned from marine paints after it was blamed for
masculinising female molluscs, causing a dramatic decline in numbers. A US
neurological disorders to pesticides. And testing by WWF (formerly the World
Wildlife Fund) found non-natural substances such as flame retardants in every
person who took part.
WWF has named chemical pollution as one of the two great environmental
threats to the world, alongside global warming, and is particularly worried
\'persistent and accumulative\' industrial chemicals and endocrine - hormone
distorting - substances linked to changes in gender and behaviour among
and even children.
\'We\'ve started seeing changes in fertility rates, the immune system,
neurological changes [and] impacts on behaviour,\' said Matthew Wilkinson, the
charity\'s toxics programme leader.
Pesticides and pharmaceutical chemicals must now undergo rigorous testing
before they can be used. But there are an estimated 80,000 industrial
and the \'vast majority\' do not need safety regulation or testing, said
However, the chemical industry strongly rejects what it claims are often
unproven fears. Just because chemicals are present does not mean they are at
But critics are not reassured. \'It is true that just because we find a
chemical does not mean it is dangerous,\' said Wilkinson. \'But it is equally
that for the vast majority of chemicals we have so little safety data that the
regulatory authorities have no idea what a safe level is.\'
The Royal Society of Chemistry also said quantities of pesticides were
declining. \'Improvements in analytical chemistry mean that lower and lower
of pesticides can be detected,\' said Brian Emsley, the society\'s spokesman.
\'[But] because you can detect something doesn\'t necessarily mean it is
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