Treating pharmaceutical waste

Disposing of pharmaceutical and other chemical waste such as lab waste can be highly problematic where there are no established treatment facilities.  

Waste can be minimised by careful stock keeping.  Keep a record of the amount of each medicine that is needed and avoid ordering too much to prevent it going out of date.  Establish a “first in first out” system in the pharmacy so that the packages which are going to expire first are dispensed first.  

Wherever possible, healthcare facilities should negotiate take-back agreements with suppliers, whereby the suppliers accept and dispose of pharmaceuticals that their customers cannot use.

Various treatment and disposal options are available for different situations.  

Cheap and easily obtained chemicals can neutralize specific drugs, particularly chemotherapeutic agents.  Many are listed in the Annexes of the WHO Guidelines on the Safe Management of Wastes from Healthcare Facilities (the Blue Book).  These are particularly useful for small amounts of liquid residues, for example in IV sets. 

Inertisation and encapsulation procedures have long been recommended by WHO in emergency situations and they are just as applicable to low resource environments. Inertisation involves taking the pills out of the packaging, mixing with liquid concrete and depositing the concrete in a landfill before it sets.

Encapsulation is the practice of putting the pharmaceuticals into barrels, which are then filled with concrete and landfilled.   This can be done more cheaply and quickly since the pills will not have to be taken out of the PVC blister packs they are usually supplied in.  These packs are not recyclable, so no useful resources are wasted.  

Finally, a little known technology called alkaline hydrolysis has good potential.  It is capable of breaking down animal tissues, killing pathogens including prions and destroying hazardous chemicals including formaldehyde and chemotherapy drugs. More research is needed to validate its use for specific pharmaceuticals.  It is cost competitive with incineration using air pollution control.

Alkaline hydrolysis are marketed as tissue digesters for the destruction of human tissues and animal carcasses but can be used for either purpose.  Unit capacities range from 10-15 kg to 4500kg per batch.  The wastes are reacted with sodium or potassium hydroxide at around 110 to 130 degrees centigrade for around 3-8 hours depending on the system and the pressure at which it is operated.    

Some alkaline hydrolysis units produce a solid residue that can be landfilled, others generate a liquid effluent.  Liquid effluents will have a high organic load and high pH but can be discharged into a sewer after neutralization or dilution.  


Key resources