London's Ulez linked to fewer emergency hospital admissions, study finds

Emergency hospital admissions in central London fell after the introduction of the T-charge and the ultra-low emission zone (ULEZ), according to new research from Imperial College London, adding to a growing body of evidence that clean air schemes deliver measurable health benefits.

Analyses were conducted on the medical records of those living in the central zone of Ulez, excluding factors such as accidents, burns, and overdose. Prior to the introduction of both the T-charge and Ulez, the annual increase in emergency admissions was at a rate of 3%.

However, with these two initiatives, there was a reversal to an annual decrease of 3%, with heart admissions falling by 8% and breathing admissions falling by 6%.

As stated by Dr Rosemary Chamberlain, who headed the research group, it was important to verify if there was indeed less hospital admission because of the known connection between poor health and air pollution.

To prove the impact of the clean air programme, researchers contrasted central London with other similar locations in the country which did not implement such initiatives.

The results about the effect on the respiratory system, however, were statistically insignificant when considering the broader context, an outcome which Chamberlain attributes to the fact that the study was limited to adults only because children are more susceptible to air pollution.

To isolate the effect of the clean air schemes, researchers compared central London with similar areas elsewhere in the country that hadn't introduced equivalent measures.

The respiratory finding, however, did not reach statistical significance once the wider trends were factored in. Something Chamberlain said may be due to the study focusing only on adults, since children tend to be more vulnerable to air pollution's respiratory effects.