The problem is that it is both a local road -providing a high street and access to residential areas for local Brixton and Lambeth residents- and also a major route into London from Sussex and Surrey with lots of traffic from/to Gatwick and areas like Croydon. We in lambeth have one of the lowest levels of car ownership in the whole country so the pollution is primarily created by buses, commercial vehicles and vehicles travelling through - solutions surely must be to reduce the traffic during the day and ensure that the traffic that does travel on the road is low polluting. I would personally extend the congestion charge zone to the South Circular to discourage traffic and raise more money - however Boris (and probably any future Labour Mayor) wouldnt want to do that. Another solution might be to extend the proposed ultra low emissions zone to cover zone 2.The consultation is now on - https://consultations.tfl.gov.uk/environment/ultra-low-emission-zone If introduced this will bring some of the benefits even if only imposed in the central area as most of the buses from Brixton head on up to the proposed central low emissions zone and lots of the taxis would also be low emission if they want to travel into central London. Another solution which I would introduce would be to introduce a congestion charge for driving to Gatwick as there is perfectly adequate public transport to get from central London to the airport.