Sarah Miller, RN September 2010
You may have heard that many different types of drugs have been found in drinking water. For example, an investigation by the Associated Press in 2008 found that municipal water supplies in several areas were contaminated with antibiotics, hormones, seizure medications, blood pressure medications, and antidepressants.[i] You are probably wondering, “What does this mean for my family’s health?” Or maybe you are worried about the effects these drugs will have on the environment. Is there anything we can do about it?
How does it affect our health?
The not-so-good news is that the effects of long-term exposure to these levels of drugs are unknown.
This is a special concern for children. Most drugs are not tested on children at all, so we have no idea how they are affected or what levels are safe for kids. Young children drink much more water for their size than adults, so the amount of drugs they are ingesting by drinking water is much larger, pound for pound.[iv]
The same drugs that are found in drinking water have also been found in ground water and in wetlands, lakes, and streams. Fish and other animals ingest this water and have been found to have significant amounts of these drugs in their systems. We still don’t know what the long-term effects will be on these animals (some of which we eat) or the environment. [v],[vi]
Many drugs do not break down quickly and can accumulate in ground water and soil, so levels could eventually become even higher.[vii]
Drugs are much more difficult than other contaminants, such as bacteria, to remove from the water supply. While new technologies are being developed to decrease the amount of certain types of drugs, there is no way to remove all of them. When some drugs enter the water supply, they are there to stay.[viii],[ix]
How do drugs get into the water supply?
Drugs get into the water supply in several different ways: by people taking them and then excreting them (through urine, for instance), from people washing residues from ointments and creams off their skin when they bathe, or when left-over or expired drugs are thrown in the trash or flushed down the toilet or drain.
What can we do about it?
While we can’t do much to limit the amount of drugs entering our water from people bathing or urinating, there are things we can do to make sure our unused medications don’t contaminate the water supply.
We can reduce the amount we throw away, either down the drain, the toilet, or in the trash can. One way to do this is by reducing the amount of leftover medication you end up with.
Ask your health care provider to give you a small supply if you are starting a new medication so you won’t have to waste so much if it if it doesn’t work or if you have a bad reaction and have to stop taking it. If your provider is prescribing something you will only be taking for a short time, be sure to ask only for the amount you need.[x]
Over-the-counter medication, such as aspirin and other pain medication, is often least expensive if bought in large quantities, sometimes including hundreds of pills. Do not buy more than you will use before the expiration date. This makes sense economically, too. After all, why would you want to pay for something that you are just going to end up throwing away?
What if we have to dispose of unused medications?
The FDA and National Office of Drug Control Policy do not recommend dumping medications in the toilet or down the drain unless they are “controlled substances” that might be abused if found in the trash.
Instead, they recommend taking medications out of their original container, mixing them with something with a strong “yuck factor” such as kitty litter, and putting them in the household trash.[xi]
Unfortunately, things you put in the regular trash are usually sent to landfills, though, where they will mix with the liquid components of household garbage. This liquid often leaks from landfills and gets into soil and ground water.[xii],[xiii]
What about bringing them to a pharmacy or a medication “take-back” event?
You may have heard of medication “take-back” events in your area, to which you can return your unused medication to be disposed of professionally. Some pharmacies also accept unused medication for disposal.
When you return medications to take-back events or pharmacies, they send them to professional medication disposal companies. These companies deal with medication waste by incinerating it.
While incineration may change the chemical structure of many drugs, it does not necessarily make them less toxic or cause them to have less of an effect on our health.
Not only does incineration create chemicals called dioxins, which are extremely toxic, it does not even prevent drugs from getting into the soil and water. When drugs are incinerated, part of them is released into the air and part of them is left over as ash. This ash is put into regular landfills. Chemicals from the ash (including medications) can get into the liquid parts of the garbage in the landfill and leak into soil and ground water.[xiv],[xv],[xvi]
As you can see, there is no simple solution to disposing of medications you don’t need. No matter what you do to dispose of medications, you can never really avoid getting them into the water. Therefore, it is best to avoid ending up with more than you need!
Still, if you end up with expired or unused medications, it is still best to get rid of them as soon as you can no longer use them. Some medications become poisonous after they are expired, so it is best not to leave them around the house.
To read the Associated Press article on drugs in the water supply entitled PharmaWater, visit:
[i] Donn, J; Mendoza, M; and Pritchard, J; AP: Drugs found in drinking water, USA Today. March 10, 2008. Retrieved from: http://www.usatoday.com/news/nation/2008-03-10-drugs-tap-water_N.htm on July 6, 2010.
[ii] Bruce, GM; Pleus, RC; and Snyder, SA.; Toxicological Relevance of Phramaceuticals in Drinking Water. Environmental Science &Technology. Online ahead of print June 2010.
[iii] Kumar, A and Xagagoraraki, I, Human Health Risk Assessment of Pharmaceuticals in Water: An Uncertainty Analysis of Metprobabmate, Carbamazepine, and Phenytion. Regulatory Toxicology and Pharmacology. 57(1) pp.146-56.
[iv] Bearer, CF. Environmental health hazards: How children are different from adults. The Future of Children. 5(2)pp.11-26, 1995.
[v] Shala, L., and Foster, GD, Surface Water Concentrations and Loading Budgets of Pharmaceuticals and Other Domestic-Use Chemicals in an Urban Watershed. Archives of Environmental Contamination and Toxicology. 58(3)pp.551-61 2010.
[vi] Metcalfe, CD; Shaogung, C; Judt, C; Li, H; Oakes, KD; Servos, MR; and Andrews, DM. Antidepressants and Their Metabolites in Municipal Wastewater and Downstream Exposure in an Urban Watershed. Environmental Txoicology and Chemistry, 29(1) pp. 79-89 2010.
[vii] Richter, O; Kullmer, C; and Kreuzig, R; Metabolic Fate Modeling of Selected Human Pharmaceuticals in Soils, CLEAN-Water, Air, and Soil. 35(5) 495-503, 2007.
[viii] Verlicchi, P; Galletti, A; Petovic, M; and Barcelo, P; Hospital Effluents as a source of Emerging Pollutants: An Overview of Micropollutants and Sustainable Treatment Options. Journal of Hydrology. Online ahead of print June 2010.
[ix] Tambosi, JL; de Senna, RF; Favier, M; Gebhardt, W; Jose, HJ; Schroder, HF; and Muniz-Moriera, RFP; Removal of pharmaceutical compounds in membrane bioreactors applying submerged membranes. Desalination. Online ahead of print June 2010.
[x] Daughton, CG; and Ruhoy, IS; The Afterlife of Drugs and the Role of PharmEcovigilance. Drug Safety. 31(12) 1069-82, 2008.
[xi] Office of National Drug Control Policy. Proper Disposal of Prescription Drugs. 2009. Retrieved from: http://www.whitehousedrugpolicy.gov/publications/pdf/prescrip_disposal.pdf
[xii] Brown, KW and Thomas, JC. A comparison of convective and diffuse flux of organic contaminants through landfill liner systems. Waste Management and Research. 16(3) pp.296-301, 1998.
[xiii] Needham, AD, Smith, JWN, and Gallagher, EMG, The service life of geomembrane polyethylene barriers. Engineering Geology. 85(1)pp.82-90. 2006.
[xiv] Singh, S and Prakash, V, Toxic environmental releases from medical waste incineration: A review. Environmental Monitoring and Assessment. 132 pp. 167-81. 2006.
[xv] Zhang, DJ, Liu, WS, Hou, HB, and He, XH. Strength, leachability, and microstructure characterization of Na2SiO3-activated ground granulated blast-furnace slag solidified MSWI fly-ash. Waste Management and Research. 25(5) pp.402-7. (2007).
[xvi] Leonard, A. Chapter 5:Disposal. The Story of Stuff. pp.207-25. Free Press. New York. 2010.