Scottish Longitudinal Study
Development & Support Unit
Early life exposure to air pollution, cognitive ability and social mobility: Analysis of the SLS Linkage to the 1947 Scottish Mental Survey
Dr Mark Cherrie (University of Edinburgh)
Prof Chris Dibben (University of Edinburgh)
Dr Lynne Forrest (University of Edinburgh)
Dr Tom Clemens (University of Edinburgh)
This project will make use of the 1947 Scottish Mental Survey (a 1936 birth cohort) linked with the Scottish Longitudinal Study. We will use these data to investigate how their early life residential environment relates changes in health and social circumstances throughout the lifecourse. We have a particular interest in how exposure to air pollutants (e.g. PM 2.5) in this historical period relate to cognitive ability, and in turn, how this affects social mobility in later life. 1) We will first investigate the spatial pattern of early life exposure to air pollution. We will consider economic (e.g. father’s social grade), social (e.g. living arrangements) and geographic predictors (e.g. urban/rural location). 2) We will determine the association between early life air pollution exposure and cognitive ability at age 11. a. We will investigate differences by sex and father’s social grade (to understand inequality in negative effects of air pollution) 3) We will investigate whether the effect of air pollution on cognitive ability at age 11 explains any of the variation in social mobility thereafter. 4) Finally we will explore the extent to which early life air pollution directly or indirectly (through reduced social mobility) might explain health in later life (a) mental health (b) general health.
This project will make use of the 1947 Scottish Mental Survey (a 1936 birth cohort) linked with the Scottish Longitudinal Study. The data from the 1947 Scottish Mental Survey provide us with age 11 cognitive ability test scores taken from children born in 1936 (Boyle 2009, Scottish Council for Research in Education 1949) Exposure to higher PM2.5 has been associated with many health outcome for example it is associated with an increase in respiratory hospital admissions in Edinburgh and Glasgow (Lee, Ferguson, and Mitchell 2009). The effects on cognitive health have received less attention, although international studies show air pollution is linked with cognitive development and decline (Clifford et al. 2016). Pollutants cause oxidative stress and myelin sheath damage in murine models (Zhang et al. 2018). Recently, PM2.5 in pre-natal and the first years of life was associated with lower working memory and conflict network (a way of measuring the development of attention through understanding how conflicts/errors are detected and resolved by the child) in primary school children, especially for boys (Rivas et al. 2019). There is a lack of understanding on how the relationship operates for people who have grown up in the same area but at different time points. In Scotland, the highest concentrations of PM2.5 were roughly 10 times higher in the 1930’s than today, so we expect to see stronger effects for people born during that time. The increased range of pollutant exposure will also allow a better understanding of the dose-response relationship. These effects may be long lasting, as shown by greater white matter lesions between children living in cities with high levels of air pollution (e.g. Mexico City), compared to small cities with low levels of air pollution (e.g. Tlaxcala)(Calderon-Garciduenas et al. 2008). Higher prenatal and early life (age 4) PM2.5 exposure was associated with the worse-than-expected change in cognitive ability from age 11 to 70 (Russ et al. 2018). A narrow focus on cognitive outcomes understates the societal cost of high air pollution. By considering air pollution as a barrier to social mobility, we can better estimate the long term contribution of air pollution to health inequalities. Intergenerational social mobility is associated with self-reported health at age 78 (Iveson and Deary 2017). One study found that babies born in the 1980’s to low income families in areas with higher air pollution were less likely to achieve upward economic mobility (O’Brien et al. 2018). The current study has the opportunity to situate these results in a cohort of the Silent Generation (born between 1924 and 1943); raised during a period of war and economic depression. In summary, the current study will elucidate the effects of air pollution on childhood cognitive development and life-long consequences
Boyle, C. 2009. "A Lifetime of Intelligence. Follow-Up Studies of the Scottish Mental Surveys of 1932 and 1947." Psychologist 22 (10):857-857.
Calderon-Garciduenas, L., A. Mora-Tiscareno, E. Ontiveros, G. Gomez-Garza, G. Barragan-Mejia, J. Broadway, S. Chapman, G. Valencia-Salazar, V. Jewells, R. R. Maronpot, C. Henriquez-Roldan, B. Perez-Guille, R. Torres-Jardon, L. Herrit, D. Brooks, N. Osnaya-Brizuela, M. E. Monroy, A. Gonzalez-Maciel, R. Reynoso-Robles, R. Villarreal-Calderon, A. C. Solt, and R. W. Engle. 2008. "Air pollution, cognitive deficits and brain abnormalities: A pilot study with children and dogs." Brain and Cognition 68 (2):117-127. doi: 10.1016/j.bandc.2008.04.008.
Clifford, A., L. D. Lang, R. L. Chen, K. J. Anstey, and A. Seaton. 2016. "Exposure to air pollution and cognitive functioning across the life course - A systematic literature review." Environmental Research 147:383-398. doi: DOI 10.1016/j.envres.2016.01.018.
Iveson, M. H., and I. J. Deary. 2017. "Intergenerational social mobility and subjective wellbeing in later life." Soc Sci Med 188:11-20. doi: 10.1016/j.socscimed.2017.06.038.
Lee, D., C. Ferguson, and R. Mitchell. 2009. "Air pollution and health in Scotland: a multicity study." Biostatistics 10 (3):409-23. doi: 10.1093/biostatistics/kxp010.
O'Brien, R. L., T. Neman, K. Rudolph, J. Casey, and A. Venkataramani. 2018. "Prenatal exposure to air pollution and intergenerational economic mobility: Evidence from U.S. county birth cohorts." Soc Sci Med 217:92-96. doi: 10.1016/j.socscimed.2018.09.056.
Rivas, Ioar, Xavier Basagaña, Marta Cirach, Mónica López-Vicente, Elisabet Suades-González, Raquel Garcia-Esteban, Mar Álvarez-Pedrerol, Payam Dadvand, and Jordi Sunyer. 2019. "Association between Early Life Exposure to Air Pollution and Working Memory and Attention." Environmental Health Perspectives 127 (5):057002. doi: doi:10.1289/EHP3169.
Russ, Tom C., Mark P. C. Cherrie, Chris Dibben, Sam J. Tomlinson, Stefan Reis, Ulrike Dragosits, Massimo Vieno, Rachel C. Beck, Edward J. Carnell, Niamh K. Shortt, Richard J. Mitchell, Adele M. Taylor, Catharine Ward Thompson, Tom Clemens, Martie J. Van Tongeren, Raymond Agius, John M. Starr, Ian J. Deary, and Jamie R. Pearce. 2018. "LIFE COURSE AIR POLLUTION EXPOSURE AND COGNITIVE DECLINE IN SCOTLAND: MODELLED HISTORICAL AIR POLLUTION DATA AND THE LOTHIAN BIRTH COHORT 1936." Alzheimer's & Dementia: The Journal of the Alzheimer's Association 14 (7):P1381. doi: 10.1016/j.jalz.2018.06.2861.
Scottish Council for Research in Education. 1949. The trend of Scottish Intelligence: A comparison of the 1947 and 1932 surveys of the intelligence of eleven-year-old pupils.: London: University of London Press.
Zhang, Q., Q. Z. Li, J. C. Ma, and Y. P. Zhao. 2018. "PM2.5 impairs neurobehavior by oxidative stress and myelin sheaths injury of brain in the rat." Environmental Pollution 242:994-1001. doi: 10.1016/j.envpol.2018.07.031.