Following reports and worrying data on the alarming pollution levels in Delhi, a Greenpeace study has found the presence of cancer-causing metals inside city schools.

The NGO analysed samples of air from Delhi classrooms between October and December 2015, and found that the heavy metal presence was alarming on days when PM 2.5 were much higher than the prescribed levels.

The study was carried out mainly to decode constituents of PM 2.5 from the sample, which was collected through monitors installed inside the classrooms. The result: The indoor air quality was five times above the Indian safety limits, and a whopping 11 times above the World Health Organisation's safety limits, taking the average to 293 (µg/m3).

Further analysis showed dangerous levels of heavy metals such as Arsenic, Cadmium, Lead and Nickel which are carcinogenic and detrimental to health.

Source: b'Representational image | Source: PTI'