Caught this in a news-service. Interesting comment at the end. If radon
is "more carcinogenic in gas form," why would they recommend driving it out
of the water into the air? Too bad there isn't some comparitive risk
noted.
Water from private wells poses risk of radiation
Mark Henderson
01/10/2001
The Times of London News International
2W
Page 12
(Copyright Times Newspapers Ltd, 2001)
PEOPLE who drink water from private wells, springs or boreholes may
be at risk from unsafe levels of radon and uranium.
Ministers have asked all local authorities to test private water
supplies for the radioactive elements after research in West Devon
found that one in seven wells contained concentrations that exceeded
safety limits. The study, carried out by the British Geological
Survey for the Department of the Environment, Transport and the
Regions, found that 15 per cent of private water sources in West
Devon contained too much radon, while 7 per cent exceeded safe
uranium levels.
In the worst case, scientists measured a radon level of 5,341
becquerels per litre, more than five times the advisory level of
1,000 set by the National Radiological Protection Board. Two firms in
the area that sell bottled spring water are within safety limits.
Private water supplies in other areas where high levels of radon gas
have been detected, such as parts of Derbyshire, Cornwall and
Northamptonshire, might also be affected, environment officials said.
There are no such problems with piped drinking water supplied by
utility companies.
Radon, thought to be the more dangerous of the two elements, has been
linked to a higher risk of stomach cancer when found in drinking
water, and radon gas is known to cause about 2,000 deaths in Britain
from lung cancer every year. Radon is less carcinogenic when
dissolved in water than in gas form.
The gas, which originates from decaying uranium, is found at trace
levels in all sorts of rocks and environments. Some types of rock,
such as granite, hold higher concentrations of the gas, leading to
clusters of high exposure. Uranium has been linked to kidney disease
at levels much higher than those found in West Devon. Though
scientists say that the risk from dissolved radon is slight, the
Environment Department has suggested to councils that the Devon
findings are "unlikely to be unique", and reminded them of their
statutory duty to maintain the wholesomeness of private water
supplies.
Any householder with a well who is concerned about radon levels can
contact their council, who will be obliged to test the water, a
spokeswoman said. Radon can be removed from water with devices that
filter it with air bubbles.
LINKS
www.nrpb.org.uk/Radnmap.htm
National Radiological Protection Board maps of radon exposure
www.environment.detr.gov.uk/radioactivity/research/complete/
index.htm
DETR radiation reports, including West Devon study
Eric M. Goldin, CHP
<goldinem@songs.sce.com>
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