Go back to main page


Posted on 11 April 2016 by Editorial team
Posted in Wastewater Management, Water and wastewater community, Tagged pharmaceuticals,

Recent studies in both the United States and Canada suggest the public and government need to pay more attention to the presence of pharmaceuticals in our water sources.

According to Environment Canada, more than 165 different pharmaceutical and personal care products have been detected in water tests. Researchers with the Environmental Protection Agency in the US found 56 active pharmaceutical ingredients in effluent samples taken from 50 wastewater treatment plants across the US.

The Canadian study, which tested samples from rivers in Southwestern Ontario, found higher than expected levels of the drugs used to treat diabetes, water retention and acid reflux. The US researchers found higher levels of blood pressure and anti-psychotic medications. Other types of drugs found in various studies include antibiotics, hormones, steroids, antidepressants, anti-seizure medications and acetaminophen.



Existing US legislation at both the state and federal levels doesn’t require wastewater treatment plants to screen for drugs, just for solids and certain types of bacteria. The Harvard Review reports that “170,000 public water systems are monitored for nearly 80 harmful substances. The prohibited nasties include bacteria, viruses, pesticides, petroleum products, strong acids, and some metals.”

Researchers say the impact of trace amounts of drugs on people is very low, but they note the risk for harm to aquatic life forms. Of particular concern are those drugs that disrupt hormones, such as birth control pills. Early research examined estrogen’s effects on fish, including abnormal sexual development. The so-called “intersex” fish found in US and Canadian rivers could be an early sign of species endangerment and other impacts on biodiversity.

In any case, water companies and municipalities need to be aware of the issues. Canadian environmental lawyer Diane Saxe notes that municipalities have been sued.

“Whether [municipalities] can mount a successful defence will depend on good monitoring of the issue, taking appropriate actions when they can, and sticking together to set reasonable standards. An insurance pool wouldn’t hurt either. […] When it comes to water safety, municipalities are much like anyone else who sells products intended to be consumed, and must provide water that is reasonably safe for consumption.”



One of the major factors in the increasing levels of pharmaceuticals in water systems is the overall higher rate of prescription drug use. The Mayo Clinic says in 2007-08, just under 50% of the population took at least one prescription drug. Today, almost 70% of Americans do. This means people are releasing more pharmaceuticals.

Other sources of drugs in the water supply are the effluents from drug-manufacturing facilities and the sewage systems near hospitals and major healthcare centres. Another key source is individual people disposing of leftover medications by flushing them directly into the wastewater system.




Pharmaceuticals in the water supply are becoming a worldwide concern. The World Health Organization carried out research in 2009 and 2010 to assess the risks to human health.  The WHO says more systematic research is needed, along with standardization for sampling and data collection. In its report, the WHO does not recommend routine monitoring except for those sites where the risk for elevated concentrations is present, such as pharmaceutical factories.

In those cases, the WHO explains, “investigative monitoring of, for example, surface water, groundwater and wastewater effluent can be undertaken to assess possible occurrence levels and exposure; if necessary, screening values can be developed in conjunction with an assessment of the potential risks to human health from exposure through drinking water.”

An even better approach, says the WHO, is to prevent entry of pharmaceuticals into our water supply. This can be done through public awareness campaigns to prevent disposal through flushing, and through the implementation of special drug collection and disposal programs. The North American Water Association, in its report, concurs, saying, “While pharmaceutical take-back programs may not lead to significant reductions in environmental loading, such activities are helpful in communicating to the public that toilets are not suitable receptacles for a diversity of consumer products.”

Of particular interest for wastewater operators is the WHO’s recommendation that plants investigate improvements in wastewater treatment to remove contaminants more easily. However, the organization also notes that a cost-benefit analysis is required to avoid costly interventions when there is no risk to human health.


California Research Bureau. (2014). Pharmaceuticals in Water: An Overview.

World Health Organization. (2011). Pharmaceuticals in Drinking Water.

About the author

At FluksAqua, we facilitate communications between industry professionals regarding new and innovative solutions. Our blogs feature experts, summary of academic articles and more.