Take a moment and think about how you might be creating waste products. Do you think of food scraps, un-recycled plastic, or exhaust from your car? True, those are valid sources of human-made waste. But have you ever considered the caffeine from your coffee, the ibuprofen you use for aches and pains, or the preservatives in lotion and makeup as a form of potentially harmful waste? These chemical contaminants often go unnoticed, washed down sinks or discarded in trash. However, there is growing evidence that chemicals from Pharmaceuticals and Personal Care Products (abbreviated as PPCPs) can create harmful impacts on our environment (Onesios, Yu, & Bouwer 2008).
What we know:
Even though we have known about PPCPs for decades, scientists have only recently begun investigating how widespread the impact of PPCPs truly is on our environment. One study revealed contamination in the majority of streams they investigated, revealing that PPCPs are not only present in the environment, they are prominent in the environment (Onesios, Yu, & Bouwer 2008). This is a problem for several reasons.
Firstly, we have no idea what the presence of these contaminants will do to the plants, animals, and microbes living in these ecosystems (Onesios, Yu, & Bouwer 2008). There are innumerable different types of PPCPs in the environment- we also do not know what they might do when mixed together. Additionally, there is the potential threat of growing microbial resistance, where bacteria gain the ability to combat the effects of antibiotics. Some PPCPs are antibacterial medications, and if they are allowed to simply exist in the environment, could contribute to the evolution of more antibiotic-resistant microorganisms. Lastly, humans share this same environment; if PPCPs end up in our groundwater or are incorporated into the plants we eat, we could end up unknowingly consuming toxins (Onesios, Yu, & Bouwer 2008).
What we can do:
So, how do we clean up these chemicals? Would you believe me if I said you could use bacteria? Believe it or not, some bacteria can actually eat PPCPs, which either removes them from the environment altogether, or turns them into different forms that might be less harmful than the original contaminant (Onesios, Yu, & Bouwer 2008). This is known as ‘bioremediation.’ Since many PPCPs are dissolved in water or buried in soil, it can be extremely difficult to remove them with physical means, like digging up all the contaminated dirt. Bacteria might be one possible solution for easy, cost effective cleanup.
One study focused on using microbial biofilms to bioremediate PPCPs (Edwards & Kjellerup 2013). A biofilm is like a blanket of bacteria. Most people are very familiar with them, even if you didn’t know until now- if you go a day without brushing your teeth, a biofilm will form on the surface of your teeth. It’s really difficult to keep your teeth cleared of these plaquey biofilms. These researchers thought the same thing might help them clean up PPCPs; since it is so hard to remove biofilms, the microbes may have a better chance to clean up contaminants if they were already in a big sheet-like mass, rather than be freely moving in the environment (Edwards & Kjellerup 2013).
What we have found:
The researchers found that biofilms are actually quite good at removing PPCPs from the environment, particularly in groundwater (Edwards & Kjellerup 2013). Biofilms can also be analyzed to determine if harmful PPCPs are in the environment, as certain biofilms can survive exposure to chemicals more effectively than others. Not only this, but biofilm bioremediation is one of the most cost-effective means of removing contaminants from the environment (Edwards & Kjellerup 2013).
This is not to say that bioremediation and biofilms are the silver bullet to solve all our problems with PPCPs. Microbes only work on the surface of contaminants, so unless there is something else introduced to the environment to break down the contamination into small, easy-to-cover pieces, microbes are very limited (Edwards & Kjellerup 2013). Additionally, microbes need multiple different types of nutrients in order to flourish, just like us. If a microbe uses up all of one type of nutrient and cannot get any more, it will not be able to grow and flourish (Onesios, Yu, & Bouwer 2008).
Another possibility that varies between different microbes and PPCPs is the end product created by the microbe’s activity. Some completely break down the PPCP, but others create completely new chemicals. In some cases, the chemical created by the microbes is more dangerous than the original PPCP (Edwards & Kjellerup 2013). Unfortunately, this is difficult to predict, and means researchers must be very careful before introducing any bioremediator into the ecosystem.
What is next?
You might be wondering, “What can I do to help keep my PPCPs out of the ecosystem?’ There are several things to consider when conducting yourself from day-to-day. Firstly, how do you dispose of medicine? The FDA recommends contacting an authorized collector to give your old medications to, and they will ensure safe disposal (FDA ‘Medicine Disposal: Questions and Answers’ 2018). You can choose to use household products made with natural ingredients, and be aware of the ‘footprint’ you are leaving on the environment.
But, perhaps most importantly, you can tell someone else about the importance of managing PPCPs. Tell them about biofilms and bioremediation, and how remarkable microbes are, to be able to clean up these toxins in the environment. After all, nothing can change unless we all take a role in becoming responsible for our actions.
Edwards, S.J. & Kjellerup, B.V. (2013). Applications of biofilms in bioremediation and biotransformation of persistent organic pollutants, pharmaceuticals/personal care products, and heavy metals. Applied Microbiology and Biotechnology. 97(23):9909—9921. doi:10.1007/s00253-013-5216-z.
FDA. 2018. Medicine Disposal: Questions and Answers. U.S. Food and Drug Administration. https://www.fda.gov/Food/DietarySupplements/
Onesios, K.M., Yu, J.T., & Bouwer, E.J. (2009). Biodegradation and removal of pharmaceuticals and personal care products in treatment systems: a review. Biodegradation. 20(4): 441-466. doi:10.1007/s10532-008-9237-8.