Taiwan Water: June 1, 2008: Upcoming study shows correlation between chlorine and birth defects.

Today seems to be a slow news day. This report from the United Kingdom says that a study that will be published next week in "Environmental Health" that shows a correlation between chlorine levels and rates of birth defects in Taiwan. Although
I'd like to see more evidence, for instance not only does the article state that other studies have not shown this correlation but it is my experience that few people in Taiwan drink water straight from the tap which makes me question what the study actually was studying, I am sure it will get attention in Taiwan and therefore the existence of the study itself is a newsworthy event.

Peter Huston
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http://www.dailymail.co.uk/health/article-1023340/Chlorine-tap-water-nearly-doubles-risk-birth-defects.html

Chlorine in tap water 'nearly doubles the risk of birth defects'

By JO MACFARLANE
Last updated at 11:47 PM on 31st May 2008

Pregnant women living in areas where tap water is heavily disinfected with chlorine nearly double their risk of having children with heart problems, a cleft palate or major brain defects, a new study has found.

Scientists say expectant mothers can expose themselves to the higher risk by drinking the water, taking a bath or shower, or even by standing close to a boiling kettle.

The danger comes from chemical by-products in chlorinated water known as trihalomethanes, or THMs, which can be absorbed through the skin. They can then pass into the womb.

At risk: Scientists have now linked chlorinated water to specific birth defects

THMs form because of a chemical reaction between chlorine and natural substances in the water.

They exist in mains water across Britain – but are highest in areas where more chlorine is added because the water quality is poor.

Earlier studies linked chlorinated water to an increased risk of stillbirth, miscarriage, birth defects and bladder cancer. But this is the first time that the risk has been narrowed down to specific birth defects.

Although a major study in 2007 by Imperial College, London, into birth defects and THM levels in Britain uncovered ‘little evidence’ of a link, the new research appears to contradict its findings.

A research team led by Professor Jouni Jaakkola of the University of Birmingham analysed the birth registry details of nearly 400,000 babies born in Taiwan between 2001 and 2003. Levels of chlorine found in water there are similar to those found in the UK.

Scientists compared the number of birth defects recorded by doctors to the level of THMs in the drinking water in different areas.

The proportions of certain specific defects were much higher in areas where levels of THMs were above 20 micrograms per litre.

The brain condition anencephalus, usually found in 0.01 per cent of births, rose to 0.17 per cent in high-THM areas.

Hole-in-the-heart defects also nearly doubled from 0.015 per cent to 0.024 per cent.

The number of cleft palates rose from 0.029 per cent to 0.045 per cent in high-THM areas.

Overall, the risks of having children with these three defects increased by between 50 per cent and 100 per cent.

There was also a slightly raised risk of urinary tract defects and Down’s syndrome.

The study appears in Environmental Health journal next week.

The number of defects could be much higher as some are not detected until later in childhood.

THM levels across Britain vary widely even within one water company area. They range from 92 micrograms per litre in south Staffordshire to just five in Hartlepool.

Most areas have levels way above the ‘high’ range in the Taiwan study. High levels were recorded in South-West England, Yorkshire and North-East Essex.

Prof Jaakkola said THMs should be cut because the biological reasons for the defects were unknown.

He said: ‘Our findings don’t just add to the evidence that water chlorination may cause birth defects but suggest that exposure to chlorination by-products may be responsible for some specific and common defects.’

Barrie Clarke, spokesman for Water UK, reassured consumers that water companies’ work was in line with the best existing information on THMs.

But he added: ‘There will be no closed minds about this new information.’