LONDON -- The Health Protection Agency, in collaboration with the London Port Health Authority (LPHA), run by the Corporation of London, is to undertake a study starting this fall, to look at the health effects of taking part in water sports on the Thames Tideway. The study aims to find out whether recreational exposure to river water containing sewage presents a risk to human health. At present, hundreds of rowers, kayakers and sailors regularly use the Thames and the risks to their health are poorly defined.
The study will be the first of its kind ever to be undertaken. Gastrointestinal illness has previously been linked to exposure to contaminated seawater on bathing beaches, and smaller studies have confirmed illness in white water kayakers. However, no study of this scale has yet been performed on a tidal river like the Thames.
There is renewed interest in contamination of the Thames, following a heavy storm on Aug. 3, 2004, which washed 600,000 tons of raw sewage into the river the following day. This caused oxygen levels to plunge, and killed thousands of fish. The aging system of combined overflows of sewage and rainwater run-off leads to discharges of untreated sewage into the Thames every time London receives heavy rainfall; the storm of Aug. 3 may have been an unusual event, but the problem of contamination of the river is a longstanding one.
Upon completion, the results of this study will be published in peer-reviewed scientific journals and will form the basis of advice to those who use the Thames for recreational purposes. These people can then take informed decisions about the possible risks of acquiring a gastrointestinal illness, particularly following periods of heavy rainfall.
Source: Health Protection Agency