Consider the multitude of chemicals that we use daily – beauty products, cleaners, cosmetics, over the counter and prescription drugs, fire retardants, food packaging, flame-retardants, hormones, nutraceuticals, pesticides, petroleum products, sunscreens, and stain repellents and numerous others. What happens to all these chemicals when they are washed down household drains or breakdown in municipal waste facilities? Where do they go?

There are hundreds, possibly thousands of compounds known as “contaminants of emerging concern” or CEC’s, including endocrine disrupting compounds (EDC’s), organic wastewater compounds (OWC’s), pharmaceuticals and personal care products (PPCP’s), polyflourylalkyl substances (PFAS), and volatile organic compounds (VOC’s), amongst others. This variety leads to a mixture in our waters resembling an alphabet soup of contaminants, of which we play a part as “cooks” as we rinse, wash away, and throw out various household items like lotions, soaps, cleaning chemicals, plastic packaging, and numerous other products.

The U.S. Environmental Protection Agency and the U.S. Geological Survey (USGS) have been investigating CEC’s for years to understand their effect on the environment and ecology, yet there remains much that we do not know. The USGS sampled 139 streams in 30 states for 95 contaminants, and found one or more of these chemicals in 80% of the streams. Further, half of the streams contained seven or more, and one-third contained an astounding ten or more of these contaminants. 

While those numbers are disturbing, drinking water is sourced differently and treated. EPA and USGS scientist’s sampled 29 drinking water plants and their source water for 210 pharmaceuticals, OWC’s, and PFAS’s. Almost 150 chemicals were detected at least once in the source water, and 121 were detected at least once in the treated drinking water. Some of the pharmaceuticals and OWC’s were observed to be more easily removed during treatment, whereas PFAS’s were more frequently detected and more resistant to treatment. 

Concentrations of these CECs tended to be relatively small, in parts per trillion, however, a few are approaching levels of concern due to known toxicity. Public drinking water supplies are increasingly testing for more contaminants and updating filtration to remove contaminants, but continued discharge of these compounds will contribute to environmental accumulation, increasing the risks to both environmental and public health.

Being aware of this threat is the first step. You can take action to reduce the amounts of these chemicals being introduced into our environment by making more informed purchases, proper recycling, and following label recommendations of disposal, especially of hazardous chemicals such as pharmaceuticals.

For more information on proper disposal of pharmaceuticals, go to https://mde.maryland.gov/PublicHealth/Pages/drug_disposal.aspx. For more information on the disposal of household chemicals, go to https://mde.maryland.gov/programs/LAND/RecyclingandOperationsprogram/Pages/hhw.aspx.