Hansell completed her doctoral research at Imperial College London on the epidemiology of chronic obstructive pulmonary disease (COPD) in the United Kingdom.
[3][4] As part of this effort, Hansell made use of historical data and models to estimate black smoke and sulphur dioxide levels across the United Kingdom in 1971, 1981, 1991 and 2001.
[12] By combining data on hospital admissions and mortality of a cohort of over three million people who live around Heathrow Airport,[13] Hansell showed that deaths due to stroke, heart and circulatory disease are more likely in areas with high levels of aircraft noise.
[17][18] She remarked that the lockdown in the United Kingdom would result in significant reductions in air pollution, in line with travel restrictions and reduced industry operation.
Hansell is a member of the Public Health England Environmental Hazards Programme Board, as well as the Government of the United Kingdom Committee on the Medical Effects of Air Pollutants.