The launch of the Low Emission Zone (LEZ) led to an improvement in test scores among primary school children in the capital, researchers at the London School of Economics (LSE) have found.
The university’s Grantham Research Institute on Climate Change and the Environment said there was a “meaningful link” between the introduction of the LEZ and Year Six pupils performing better in their SATs.
Launched by mayor Ken Livingstone in 2008, the LEZ covers all of Greater London and only applies to heavy vehicles like lorries, vans and minibuses. It requires them to meet certain emission standards to avoid a daily charge of up to £300.
To isolate the specific impact of the LEZ, the study compared London school results between 2005 and 2015 with a group of urban schools in England's 20 largest cities which are more than 100km from the LEZ border.
Compared to their peers across the country, pupils in London experienced “a 0.09 standard deviation improvement in test scores”, which the paper’s authors called “highly statistically significant”, adding that it is “similar to the estimated effect of reducing class size by 10 students or paying teachers large financial bonuses”.
The research does not provide a definitive explanation for the findings.
However, its authors suggest that “reduced air pollution may directly enhance cognitive performance and cognition” and that “by lowering air pollution, LEZs likely reduce respiratory-related school absences, allowing students to attend more consistently, which can enhance academic performance”.
The study found that the benefit was “disproportionately greater in schools serving a larger share of economically disadvantaged populations and those with historically lower academic performance”.
It said this indicates “LEZs can play a critical role in levelling the educational playing field and supporting vulnerable communities”.
The research formed part of an independent study, and was not commissioned by City Hall.
The LEZ is not to be confused with the Ultra Low Emission Zone (ULEZ), which was introduced several years later and applies to all motor vehicles which fail to meet emission standards, not just larger ones.
