The same way we look back in horror at the earlier air quality of London, when everyone burned cheap coal for home heating and 'pea-souper' fogs were a thing, b

The same way we look back in horror at the earlier air quality of London, when everyone burned cheap coal for home heating and 'pea-souper' fogs were a thing, before the Clean Air Act: https://en.wikipedia.org/wiki/Pea_soup_fog https://en.wikipedia.org/wiki/Pea_soup_fog