London's Tower Bridge on a not-so-clear day

Suppressing air pollution would seem to be a good thing, but in London it is brewing as a political hot topic just days prior to the May 3 London mayoral election.

The Labour Party is accusing Conservative Party Mayor Boris Johnson of purposely suppressing air pollution readings around city monitors by gluing dust particles to the road. Presumably, this is done to provide better pollution reports so as to enhance Johnson’s reputation as a pollution fighter. The Guardian reports on whether the mayor is suppressing pollution around the air monitors or really improving the city’s poor air quality:

Barry Gardiner, one of the [Labour] MPs who have written to the environment secretary Caroline Spelman to ask her to investigate, said the pollution suppressants were “like putting an oxygen mask on the canary in the mines”.

But Leon Daniels, managing director of surface transport at Transport for London (TfL), which is conducting the suppressant trials, said: “TfL has always been clear that the use of dust suppressants across London is in combination with other measures to reduce harmful PM10 particle levels at a range of locations where we know there are higher levels of this pollutant. This is in addition to a range of longer term, sustainable measures aiming to reduce pollution levels at source across the capital.”

So no one is denying the use of dust suppressant agents. It is just a matter if it is being done for political reasons to distort the air pollution reports or to really suppress dust.

The MPs say Johnson has spent £1.5m on the pollution suppressant programme. They said that harmful pollutants were being stuck to the road “in an attempt to artificially reduce the readings around air quality monitoring stations”, in a manner that would mislead people about the real quality of the air they are breathing.

“After four years as mayor it is disappointing that his only solution to tackling air pollution in London is to glue it to the road,” the MPs said in the letter.

Johnson’s office responded that everything is legitimate.

A spokeswoman at the department for the environment said: “There’s a lot being done to reduce pollution in London, the use of dust suppressants being one. There has been an improvement in air quality in areas where it has been trialled, and there is no evidence to suggest its use artificially reduces the readings around the monitoring stations.”

The truth probably lies somewhere in between. Perhaps London is spraying suppressants near the monitors in greater proportion, but then those monitors may have been placed in particularly dusty areas that needed the spraying. Whatever the truth, this is probably the first time a politician has been criticized for reducing air pollution. In the end, it will be the London voters who will decide if Johnson is a real pollution fighter or just a pollution suppressing opportunist.