Dirtied by success? Nigeria is home to city with worst PM10 levels

Story highlights

  • Onitsha has the worst PM10 levels in the world, according to a new report
  • Four of the worst cities in the world for this were located in Nigeria -- Africa's largest economy
  • The WHO urges all cities to start monitoring their pollution levels

(CNN)The word "Africa" often evokes romantic images of elephants crossing the Kalahari, thundering water at Victoria Falls, or panoramic views from Table Mountain.

But an increasingly common sight for Africans -- especially those in Nigeria -- is that of smog, rubbish and polluted water, according to a new report.
Four of the worst cities in the world for air pollution are in Nigeria, according to data released by the World Health Organization (WHO).