This is a letter from Charlie Bolton, leader of the Green group of councillors to the Bristol Post
I note with interest your report ‘Health warning as air pollution in Bristol peaks at 'unhealthy' levels’ (the Post 23rd January). In it, you highlight the spike in PM2.5 particulate pollution on that date – with levels described as ‘Unhealthy’ coming from the one monitoring site in St Pauls for that date.
It should be noted that – according to the World Health Organisation there is ‘There is no evidence of a safe level of exposure or a threshold below which no adverse health effects occur.’ So you would think that ‘Unhealthy’ should be the minimum reading on any measure of such pollutants.
It should also be noted that the governments(2) own advice on air pollution (from, DEFRA) states ‘levels of PM2.5 ….close to roadsides are often much higher than those in background locations’.
So given that the station in St Pauls is away from main roads, given there is only one of them (and there are lots of main roads in the city), given the advice from the WHO and DEFRA, you have to reckon that not only do we describe this pollutant in overly optimistic terms.
But we don’t even measure it very well.
Yours etc etc