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Longer-lasting Drugs Are Persisting in Water Supplies

Residues from the medicines we take are increasingly finding their way into our drinking water, according to James Cook University scientists who are attempting to use ultraviolet and natural light to remove pharmaceutical leftovers from the environment.

“There’s ongoing debate over what impact small amounts of pharmaceuticals in the water supply have on the environment and ultimately humans,” said A/Prof Michael Oelgemoeller. “But studies have shown serious concerns regarding their accumulation in water supplies. The effects range from impacts on animal behaviour and populations to the enhancement of bacteria resistances.”

Oelgemoeller said the latest therapeutic drugs were designed to be more stable so they lasted longer in the body and were more effective, but this had a downside. “Newer compounds are better able to resist metabolism by the human body. But when these compounds are released into the waterways, they now persist longer and in more powerful concentrations.”

“A recent environmental study has shown the presence of drugs has a significant impact on the feeding behaviour of fish. So in addition to the possible threat to humans, having pharmaceutical agents in the water could be seen as a threat to the Great Barrier Reef, the aquaculture industry and ultimately public health.”

He said evidence was emerging that even the most modern water treatment systems were unable to completely remove pharmaceutical residues. Hence, these compounds find their way into our drinking water supplies.

“Recent studies from around the world have demonstrated that pharmaceuticals survive even the most advanced conventional water treatment processes.”

Oelgemoeller said the team was investigating UV light and natural sunlight as a sustainable, low-cost alternative to artificial light. The team also uses natural minerals as catalytic materials and absorbents that aid in the removal of drug residues.