The Met Office is forecasting that tomorrow (Tuesday) and on Wednesday, London will hit the worst level on its scale for air pollution.
The level 10 warning – out of a possible 10 – comes with the warning that those with lung problems and adults with heart problems should avoid strenuous activity.
Anyone who is experiencing a cough, or sore eyes or throat, should consider reducing their activity levels, in particular outdoors, the Met Office advises. Outdoor physical exertion should in general be reduced.
Those with asthma are likely to find that they need their inhaler more often, the Met Office cautions.