Research and policy
SAHSU research is designed to have public health and policy relevance. Two examples of recent policy-relevant research are:
Possible health risks for populations living around landfill sites
Between 2001 and 2009 the Small Area Health Statistics Unit - SAHSU (based at Imperial College) published results from the most extensive study ever conducted into health effects of landfill sites. This work was initiated due to public concern over whether humans are exposed to toxic chemicals in landfill (which accounts for over 80% of municipal waste in Britain) and suffer adverse health consequences as a result [1-5]. The rates of birth defects, low birthweight, stillbirths, and of certain cancers in populations living within 2km of landfill sites were studied.
The key findings of the study are as follows:
- The study found no increase in rates of cancer in populations living close to landfill sites
- There was a small unexplained excess of congenital anomalies (birth defects) in populations living within 2km of landfill sites.
- However, rates of congenital anomalies did not increase, and in some cases reduced, after landfill sites were opened in certain areas so the landfill sites may not have caused the excess.
- There was a small excess of low birthweight babies living within 2km of landfill sites.
- There was no difference in the rate of stillbirths.
- The findings were considered by the Government's expert advisory Committee on the Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) in both 2001 and 2011 [6-7]. COT noted that the findings for the birth outcomes were not consistent and that the study provided no evidence that rates of anomalies increased after landfill sites opened. The COT recommended that the finding of a 7 per cent higher rate of congenital anomalies around special waste sites merited further investigation, whether or not it was related to the presence of the landfill sites. The COT statement has been published on the COT website [6-7].
The protocol and results of the study have repeatedly been discussed in Parliamentary Questions in 2000, 2002, 2003, 2004 whenever questions relating to the possible health effects of landfill sites have been asked . The work and the statements by the COT have also been picked up by both the national and local press [9-10].
1. P Elliott, D Briggs, S Morris, C de Hoogh, C Hurt, T Kold, Jensen, I Maitland, S Richardson, J Wakefield, L Jarup. Risk of adverse birth outcomes in populations living near landfill sites BMJ 2001;323 doi: 10.1136/bmj.323.7322.1182b
2. L Jarup, D Briggs, C de Hoogh, S Morris, C Hurt, A Lewin, I Maitland, S Richardson, J Wakefield and P Elliott. Cancer risks in populations living near landfill sites in Great Britain British Journal of Cancer 2002;86:1732–1736. doi:10.1038/sj.bjc.6600311
3. S Morris, AO Thomson, L Jarup, C de Hoogh, D Briggs, P Elliott. No excess risk of adverse birth outcomes in populations living near special waste landfill sites in Scotland. Scott Med J. 2003;48(4):105-7.
4. L Jarup, S Morris, S Richardson, D Briggs, N Cobley, C de Hoogh, K Gorog, P Elliott. Down syndrome in births near landfill sites Prenat Diagn 2007;27:1191–1196. DOI: 10.1002/pd.1873
5. Elliott P, et al. Geographic density of landfill sites and risk of congenital anomalies in England. Occup Environ Med 2009;66:81-89.
6. COT statement on a study by the Small Area Health Statistics Unit (SAHSU) on health outcomes in populations living around landfill sites - August 2001. Available at: http://cot.food.gov.uk/cotstatements/cotstatementsyrs/cotstatements2001/sahsulandfill
7. COT second statement on landfill sites. Available at: http://cot.food.gov.uk/pdfs/cotstatementlandfill201001.pdf
8. Parliamentary Questions –Hansard records. Available at:
9. BBC news: ‘Birth defect linked to landfill sites’ August 16 2001 Available at: http://news.bbc.co.uk/1/hi/health/1494567.stm.
10. Environmental Health News: ‘Landfill health effects investigated’ August 5 2011. Available at: http://www.cieh.org/ehn/ehn3.aspx?id=38150
Association between socio-economic status and air pollution exposure in England and the Netherlands
Research on inequalities in environmental exposure to air pollution was presented by Daniela Fecht (SAHSU Research Associate) at the 2011 International Society for Environmental Epidemiology was referred to by the UK House of Commons Environmental Audit Committee in their report on Air Quality.
Air quality: A follow up report - Environmental Audit Committee
"Initial findings of research by Imperial College and environmental research groups in the Netherlands suggest that poor air quality is hitting the poorest hardest. That research is examining the associations, at a local level, between air pollution and socio-economic groups. Preliminary findings for the Netherlands, presented in September 2011, indicated that pollution levels increased with higher degrees of urbanization, higher numbers of non-western immigrants and lower house prices, while preliminary results for England indicated that poor air quality is associated with areas of low income, low employment and low educational attainment, with differences in exposure to air pollution between different ethnic groups. Several other studies have also shown that elevated levels of pollution are concentrated amongst socially deprived neighbourhoods.”
1. Fischer P; de Hoogh K; Fecht D; Marra M; Kruize H; Hoek G; Beelen R; Vienneau D; et al. Associations between small area levels of air pollution and socio-economic characteristics in the Netherlands and England. ISEE 2011