
The levels of poisonous nitrogen dioxide gas were even worse than those recorded in November, when two of three Streatham monitors broke legal limits.
Local campaigner Chris Holt, who is helping to monitor air quality outside Streatham and Clapham High School in Daysbrook Road, Streatham Hill, said: "Even on these quiet side streets away from the busy main road, the pollution caused by diesel engines was dangerously high in both November and December."