Open Access Highly Accessed Open Badges Research

Socioeconomic status and exposure to disinfection by-products in drinking water in Spain

Gemma Castaño-Vinyals123*, Kenneth P Cantor4, Cristina M Villanueva123, Adonina Tardon35, Reina Garcia-Closas6, Consol Serra78, Alfredo Carrato9, Núria Malats10, Nathaniel Rothman4, Debra Silverman4 and Manolis Kogevinas11123

Author Affiliations

1 Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain

2 Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona, Spain

3 CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain

4 Division of Cancer Epidemiology and Genetics, National Cancer Institute, Department of Health and Human Services, Bethesda, USA

5 Universidad de Oviedo, Oviedo, Spain

6 Unidad de Investigación, Hospital Universitario de Canarias, La Laguna, Tenerife, Spain

7 Universitat Pompeu Fabra, Barcelona, Spain

8 Consorci Hospitalari Parc Taulí, Sabadell, Spain

9 Hospital General de Elche, Elche, Spain

10 Centro Nacional de Investigaciones Oncológicas (CNIO), Madrid, Spain

11 Department of Social Medicine, Medical School, University of Crete, Herakleion, Crete, Greece

For all author emails, please log on.

Environmental Health 2011, 10:18  doi:10.1186/1476-069X-10-18

Published: 16 March 2011



Disinfection by-products in drinking water are chemical contaminants that have been associated with cancer and other adverse effects. Exposure occurs from consumption of tap water, inhalation and dermal absorption.


We determined the relationship between socioeconomic status and exposure to disinfection by-products in 1271 controls from a multicentric bladder cancer case-control study in Spain. Information on lifetime drinking water sources, swimming pool attendance, showering-bathing practices, and socioeconomic status (education, income) was collected through personal interviews.


The most highly educated subjects consumed less tap water (57%) and more bottled water (33%) than illiterate subjects (69% and 17% respectively, p-value = 0.003). These differences became wider in recent time periods. The time spent bathing or showering was positively correlated with attained educational level (p < 0.001). Swimming pool attendance was more frequent among highly educated subjects compared to the illiterate (odds ratio = 3.4; 95% confidence interval 1.6-7.3).


The most highly educated subjects were less exposed to chlorination by-products through ingestion but more exposed through dermal contact and inhalation in pools and showers/baths. Health risk perceptions and economic capacity may affect patterns of water consumption that can result in differences in exposure to water contaminants.