NEW DELHI: Tonnes of antibiotics, painkillers and other medicines are flowing down the Yamuna, and scientists at AIIMS say our habit of throwing away leftover medicines in household garbage is partly to blame for this.
The drugs could be coming back to us in milk, vegetables and other agricultural produce, and also giving rise to superbugs that most antibiotics cannot kill.
In 2015, researchers from AIIMS’ ocular pharmacology division started studying pharmaceutical contamination in the Yamuna to explain the emergence of superbugs.
The team, headed by Dr T Velpandian, analysed water samples from seven places along the river, including its entry and exit points in the city, 35 bore wells in Delhi NCR and water percolating through waste at the Ghazipur landfill. They found the concentration of dissolved drugs increased manifold along the Yamuna’s course.
At its entry near Wazirabad in north Delhi, concentrations of fluconazole (antifungal), ofloxacin (antibiotic) and ibuprofen (painkiller) were less than 0.05 micrograms per litre.
A microgram is a millionth of a gram, so 20 million litres of river water contained 1g or less of these drugs. The painkiller diclofenac was present in double strength — 0.1 microgm a litre.
Antibiotics you throw away may be breeding superbugs
‘Drug concentrations alarmingly high in groundwater near Ghazipur landfill’
The unused drugs that you dispose of without a second thought could be coming back to you in milk, vegetables and other agricultural produce.
At the Yamuna’s exit near Okhla barrage, the concentrations of fluconazole, ofloxacin and ibuprofen increased by 80, 96 and 50 times, respectively. Diclofenac increased by 121 times. The team’s findings have been published in the latest edition of the journal Environmental Science and Pollution Research.
To find out the sources of pollution, the researchers tested groundwater samples and also the water percolating from the Ghazipur landfill. “We found alarming drug concentrations towards the area adjacent to Ghazipur landfill,” Dr Velpandian said.
“This means that a lot of unused drugs, expired or not, are thrown into dustbins, end up at the landfill, and from there percolate into the local drains and finally end up in the Yamuna.”
He said Delhi and other densely populated areas need a strict policy for separating and destroying bioactive compounds so that they do not accumulate in the environment.
“We recommend continuous monitoring for bioactive compounds in water resources and creating awareness on disposal of unused or expired medicines through responsible organisations.”
L Moksha, co-author of the study, said that in some developed countries unused drugs have to be returned to pharmacies and they are incinerated. People throw away expired medicines thinking they are useless but “they are still active though their potency may have decreased”.