Exposure to chemical in drinking water linked to bladder cancer

By TPN/Lusa, in News · 18-01-2020 16:00:00 · 1 Comments

More than 6,500 cases of bladder cancer per year, around 5% of all cases in Europe, including Portugal, can be attributed to exposure to chemicals (trihalomethanes) in drinking water, warns a study.

According to the results of a study by researchers from the Barcelona Institute of Public Health (ISPB), released in a statement, Portugal is among the countries where the concentration of compound trihalomethanes (THM) has peaks that exceed the maximum of 100 micrograms per litre allowed in the EU and which are also stipulated in national legislation. The data compiled by the study indicate, however, that the average annual THM concentration in tap water in Portugal is 23.8 micrograms per litre.

Trihalomethanes (THM) are formed in the water disinfection process and are a set of four organic compounds: Chloroform (CHCl3), Bromodichloromethane (CHBrCl2), Dibromochloromethane (CHBr2Cl) and Bromoform (CHBr3). The carcinogenic potential of THM was already known, but the study released today aims to establish a direct relationship between exposure to these compounds and cases of bladder cancer.

"Previous research had established an association between prolonged exposure to THM - whether by ingestion, inhalation or dermal absorption - and increased risk of bladder cancer," says the ISPB statement.

ISPB analysed the presence of trihalomethanes in tap water from 26 EU countries except Bulgaria and Romania.

Countries with the highest incidence of bladder cancer cases attributable to THM exposure are Cyprus (23%), Malta (17%), Ireland (17%), Spain (11%) and Greece (10%). Portugal has an incidence of 9.1%.

At the other extreme are Denmark (0%), the Netherlands (0.1%), Germany (0.2%), Austria (0.4%) and Lithuania (0.4%).

The authors of the study, published in the scientific bulletin Environmental Health Perspectives, analysed recent data on THM levels in Europe's municipal water networks and estimated the disease burden for bladder cancer attributable to exposure to this compound.

Data were obtained from 2015 to 2018 in 26 EU countries, covering 75% of the population, which showed considerable differences between countries.

The average level of trihalomethane in drinking water was below the maximum EU limit in all countries, but reported peak concentrations exceeded the limit in nine countries (Cyprus, Estonia, Hungary, Ireland, Italy, Poland, Portugal, Spain and the United Kingdom).

The potential number of cases of bladder cancer has been estimated by statistical calculation by relating average THM levels to available international information on bladder cancer incidence rates in each country.

In total, researchers concluded that 6,561 cases of bladder cancer per year in the EU are attributable to exposure to trihalomethanes.

The authors recommend that countries with higher levels of THM in treated water make efforts to reduce these compounds and estimate that if the 13 countries with the highest levels of THM reduced this concentration, 44% of annual bladder cancer cases attributable to exposure to THM could potentially be avoided.


This is a very worrying news! It is a no-win situation where you can either seriously risk danger to your health by using tap water or you can contribute to the demand
for single-use plastic by buying water in plastic bottles. I do not want to do either and I live in Portugal!

By Steve Andrews from Other on 19-01-2020 03:21
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