World's rivers contaminated with high level of antibiotics, study finds.

BEIJING: Most of the major rivers in the world, a majority of them in Asia and Africa, are contaminated with an alarming level of antibiotics. In some countries, it exceeded the prescribed limit by nearly 300 times, a global study found.

Researchers from the University of York tested river water in 72 countries including Pakistan to measure the level of 14 commonly used antibiotics. Nearly two-thirds of the samples collected showed a severe concentration of the drug, China Global Television Network (CGTN) reported.

"Sites where antibiotics exceeded 'safe' levels by the greatest degree were in Bangladesh, Kenya, Ghana, Pakistan and Nigeria," researchers said.

One sample from Bangladesh had metronidazole -used for treating skin infections - exceeded the safe limit by 300 times. Overall, antibiotics concentration in the country's rivers was 170 times higher than the prescribed limit.

Globally, trimethoprim, prescribed for treating urinary tract infections, emerged as the most common antibiotic present at 307 of the 711 sites.

Serious contamination was also found in most developed nations, including those in Europe, North America and South America.

At the Thames River, five antibiotics, including ciprofloxacin - used to treat skin and urinary tract infections - were three times over what's considered safe.

Dealing with the logistical challenge of transporting 92 samples collected from various rivers around the world, researchers managed to fly back frozen samples to the University of...