Interested in this kind of news? Receive them directly in your inbox. Delivered once a week. Sign Up "The huge reduction in nitrogen dioxide levels during the lockdown – on top of the substantial drop already achieved by the ULEZ in the past year - shows that traffic is the dominant source and that reducing car use is the most effective way to permanently cut the breathed pollution. As life begins to return to normal it is essential that traffic and air pollution levels do not return to harmful levels to both reduce the risk to people that will contract cornoavirus in the future; and vulnerable people with respoiratory diseases as result of contracting the virus. Allowing toxic air to return will underdo the huge sacrifices of health workers and citizens and replace one health crisis with another. The Mayor, and the government, have a responsibility to continue to restrict car use after the lockdown and to ensure their is a green recovery. In transport, money must in particular be invested maintaining the habit of walking and cycling and unblocking congested bus routes. Dirty vehicles must be banned from London and scrappage schemes used to remove the most polluting vehicles and replace these with public travel vouchers or zero emission electric vehicles. Every effort must now be made to banish toxic air with the virus."