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Investigation of possible relationships between chlorination by-products and adverse pregnancy outcomes - WT02030

There have been a number of published studies on the possible effects of chlorination by products and other drinking water contaminants on the outcome of pregnancies.

While all such studies have been subject to significant limitations, in particular in connection with estimation of exposure, some have shown possible associations between a range of adverse pregnancy outcomes and various disinfection by-products, in particular THMs, and chlorinated solvents, in particular trichlorethene.

Chlorination is the mainstay of drinking water disinfection practise in the UK and it has been instrumental in the virtual elimination of public drinking water as a source of infection.

O1: Test the hypothesis that the concentration of THM in drinking water supplies correlates with the rate of adverse pregnancy outcomes.

02: Determine significant foetal development defects and all other pregnancy outcomes.

03: Establish arrangements with relevant water companies to obtain water quality data.

04: Investigate whether changes in water treatment to reduce THM result in any detectable reductions in cases of adverse pregnancy outcome.

05: Develop as necessary and apply suitable statistical techniques to seek for significant correlation and take account of possible confounding factors.
Project Documents
• Final Report : Chlorination disinfection byproducts and risk of congenital anomalies in England and Wales   (2754k)
Time-Scale and Cost
From: 2003

To: 2006

Cost: £148,573
Contractor / Funded Organisations
The Imperial College of Science Technology and Medicine
Birth Defects              
Birth Weight              
Cleft Lip              
Cleft Palate              
Drinking Water              
Health Effects              
Fields of Study
Water Quality