River Ravi in Pakistan is the most polluted river in the world, followed by water bodies in Bolivia and Ethiopia, a US-based research academy has said, warning that local populations in these areas are exposed to serious risks. In its study, the University of York monitored 1,052 sampling sites along 258 rivers in 104 countries across all continents to quantify the presence of pharmaceutical ingredients - paracetamol, nicotine, caffeine and epilepsy and diabetes drugs - in these ecological environments.


  1. The study concluded that contaminants in surface water posed a threat to environmental and/or human health in more than a quarter of the studied locations globally - mainly in sub-Saharan Africa, South Asia, and South America.
  2. The highest mean cumulative concentration was observed in Lahore, capital of Pakistan's Punjab province, at 70.8 µg/L, with one sampling site on the Ravi River reaching a maximum cumulative concentration of 189 µg/L.
  3. This was followed by La Paz river in Bolivia (68.9 µg/L mean, 297 µg/L maximum) and the river system in Addis Ababa, Ethiopia (51.3 µg/L mean, 74.2 µg/L maximum).
  4. The most common contaminants were paracetamol, nicotine, caffeine and epilepsy and diabetes drugs in the river, according to the study which was published in the journal of Washington-based National Academy of Sciences.
  5. Rivers in Iceland, Norway and the Amazon rainforest were recorded as the cleanest.