Professor Barbara Maher “astonishes” the BBC when her pollution reduction experiments are shown on TV.

Producers from the BBC2‘s Trust me I’m a Doctor series contacted Barbara after reading her research suggesting that trees can reduce the amount of traffic-derived pollution getting into people’s houses. 

They asked Barbara, from the Lancaster Environment Centre, to conduct some experiments on the busy A6 road in Lancaster and then filmed the results. 

Thirty birch trees in wooden planters were placed outside homes on South Road for a two-week experiment this summer and the results were revealed during the show. Birch trees were chosen because their leaves are rough and hairy and so are good at intercepting the dangerous particulates in vehicle emissions. 

Presenter Michael Mosley was “utterly astonished” when Barbara’s experiments showed that a line of small birch trees reduced harmful particulates inside people’s front rooms by between 50 and 60 percent. 

“Very, very, very impressive”

Michael told Barbara that: “when I first heard about this I was extraordinarily sceptical. I was expecting possibly a tiny shift because they are little trees. It’s very, very, very impressive.”

The line of trees is what’s important,” Barbara told him. “You don’t need a forest, you don’t need a continuous canopy, its that’s edge that provides the interception of the particulates before they get into people’s houses.”

The programme quoted government research suggesting that 29,000 people die in the UK each year from particulate pollution. 

“It was great that the BBC provided the means to carry out the tree experiment, both to raise people’s awareness of the health hazard of traffic-derived particulates, and to see just how effective roadside trees can be in reducing the problem,” she said.