Pharmaceuticals In Drinking Water

More than half of Americans regularly take prescription medication. Of those who take a prescription, most take four different medications a day. And these numbers are rising steeply: in 1997, Americans filled 2.4 billion prescriptions. In 2016, the number increased to a whopping 4.5 billion.

While modern drug therapies play an important role in overall health, and these medications save lives every day, there are also problematic side effects for the individual and the environment. After a person has used their medication and it's passed through their body, those pharmaceuticals go into our sewage and waste water, where they end up in the environment, and often in our drinking water. 

Drugs and their metabolites (substances formed as the body metabolizes a drug) enter our water supply in several ways:

• As residual amounts in sewage and waste water from the homes of those who are taking the pharmaceuticals
• As effluents and runoff from drug manufacturing and production facilities, particularly those that are poorly controlled and have little oversight
• As agricultural runoff from animal production facilities, where pharmaceuticals are present in the excreta of animals that receive them
• Some studies also show that people flush unused prescriptions down the toilet to dispose of them.

These are bioactive chemicals, designed to have pharmacological effects on a person, but have unintended effects in the environment and drinking water supply. Pharmaceuticals are controlled substances, after all, and not intended to be consumed by anyone other than a person with a demonstrated medical need.

The broad term “pharmaceuticals” also includes over the counter and personal care chemicals, ranging from vitamins and painkillers, to active ingredients in shampoos and cosmetics.

While these drugs have all be found in tap water, they are only present in trace amounts and at safe levels. However, the fact that these drugs are present at all is a cause for some concern, when you consider that they may be unintentionally taken by those for whom the drug poses a health risk, such as those with existing liver or bone marrow disorders, or by pregnant women.

The World Heath Organization has assessed drinking water in the UK, Australia, and the United States, and determined that the concentrations of pharmaceuticals in drinking water are below the level of dosage that would have a negative effect, and that adverse health effects in humans are “extremely unlikely”

However, human health risk from direct consumption of tap water is not the only risk from these high levels of pharmaceuticals. For example, according to the National Center for Biotechnology Information, there are a number of additional effects, including:

• Food plants irrigated with waste water can have enough carbamazepine metabolites and lamotrigine to have a clinical effect on a human when, for example, eating a carrot.
• Waste water from a hospital in Spain was found to contain enough ibuprofen to pose a risk to aquatic organisms.

Furthermore, this is a problem that will only get worse over time, as the levels of available fresh water decrease, and prescription medication usage continues to increase.

The biggest determinant of how much and what kind of pharmaceuticals end up in our drinking water is what kind of filtration methods are being used by the government or utilities that supply the water. Advanced countries usually employ several methods for treating and filtering water for human consumption, including:

• Granular activated carbon
• Membrane technologies
• Ozone treatments
• Ultraviolet radiation

But not all countries have the facilities to treat their drinking water with these methods, and, unfortunately, even with all these treatments, some compounds remain unaffected.

More work needs to be done by governments and regulators. However, there are several steps that consumers can take to prevent pharmaceuticals from getting into the water supply in the first place:

Following these steps will reduce the number of pharmaceuticals available in our waste water, protecting human health and the environment.