Environmental impact of some medications

Medications, including aspirin, paracetamol, antibiotics, and hormones, may end up in the environment, primarily via the sewage system.
This happens through the excretion of unmetabolised drugs or metabolites, or by improper disposal of medicines.
Wastewater treatment plants can’t fully remove all these pharmaceutical compounds, resulting in their release into rivers and other water bodies.

Some of these compounds may have an adverse effect on aquatic life. For example, diclofenac, a common NSAID, has been implicated in the decline of vulture populations in Asia.
Hormones, such as those used in birth control pills, can disturb the normal functioning of endocrine systems in fish and other aquatic organisms.
Research has shown that certain fish species can exhibit changed behaviour, impaired reproductive capacity or, in extreme cases, undergo sex changes as a result of exposure to hormone pollutants.

The presence of antibiotics in the environment can lead to the development of drug-resistant pathogens, a growing global health concern.
Resistance can develop when bacteria are exposed to sub-lethal concentrations of antibiotics which don’t kill them but instead promote the survival of those with resistance genes.

The concept of “Green Pharmacy” has been developed to minimise the environmental impact of medications.
This could include the development of drugs that are biodegradable or that have improved biotransformation rates in humans, reducing the amount excreted.
Another aspect of green pharmacy is the proper disposal and waste management of unused or expired medications to prevent them from entering the environment.

The 3Rs strategy of reduce, reuse, recycle is a key part of waste management - including pharmaceutical waste.
Hospital pharmacies, for example, can review their stocks regularly and manage orders to minimise waste.
The public can also contribute by returning unused or expired medications to pharmacies, who often have take-back programs, instead of throwing them in the bin or down the toilet.