Use of biocides and insect repellents and risk of hypospadias
- 1Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- 2IMIM, Barcelona, Spain
- 3CIBERESP, Barcelona, Spain
- 4Department of Epidemiology and Public Health, Imperial College London, London, UK
- Correspondence to Dr Mark J Nieuwenhuijsen, Center for Research in Environmental Epidemiology (CREAL), Parc de Recerca Biomèdica de Barcelona - PRBB (office 183.05), C. Doctor Aiguader 88, 08003 Barcelona, Spain;
- Accepted 30 July 2009
- Published Online First 1 December 2009
Background The relationship between the use of biocides and insect repellents and the risk of hypospadias was examined in a large case–control study in the South East of England.
Methods A case–control study was carried out among 471 cases of hypospadias referred to surgeons, and 490 randomly selected population-based controls, born between 1 January 1997 and 30 September 1998. Telephone interviews were conducted between September 2000 and March 2003. The questionnaire included information on demographic, lifestyle and environmental factors, including the use of biocides and insect repellents, during pregnancy. A total biocide score was created from summing positive responses to an eight-item biocide exposure questionnaire.
Results The use of insect repellent (adjusted OR 1.81, 95% CI 1.06 to 3.11) during the first trimester of pregnancy was associated with risk of hypospadias, but none of the biocides, or indicators for them, except for the total biocide score for the highest two exposure categories (score 3: adjusted OR 1.73, 95% CI 1.02 to 2.94; and scores 4 and 5 combined: adjusted OR 2.98, 95% CI 1.01 to 8.78) showed statistically significant associations.
Conclusion The authors found an association between the use of insect repellent and total biocide score and risk of hypospadias. In particular, the use of insect repellent warrants further investigation, specifically in relation to type, content and frequency of use since this information was missing in the current study.
Funding The study was funded by a grant from the UK Health and Safety Executive/Department of Health/Department of the Environment, Transport and The Regions/European Chemical Industry Council (CEFIC). Paul Nelson was supported by a Wellcome Trust Research Training Fellowship in Clinical Epidemiology and also in part by the North Thames Training Programme in Public Health Medicine. The study sponsors had no role in the study design, data collection, analysis and interpretation, or writing of the paper.
Competing interests None.
Ethics approval Ethics approval was given by the West Midlands Multi-centre Research Ethics Committee, Birmingham, United Kingdom.
Provenance and peer review Not commissioned; externally peer reviewed.