The Full Story
There are many ways for pharmaceuticals and personal care products to enter ground water and surface water. These include water that we drink and that we use for recreation such as swimming, fishing, and boating. Of course, water also is home to a multitude of aquatic animals. There are no studies to date documenting human harm from the trace amounts of pharmaceuticals and personal care products measured in water, but there are studies in animals which indicate possible concerns. Even though substantive measures would require major resources and cooperation by a number of government and private entities, there are steps that individuals can take to limit the amount of pharmaceuticals and personal care products that they introduce into ground and surface water.
How and why should consumers be concerned about drug disposal?
The federal government offered consumers the first-ever nationwide guidelines for disposing of household drugs in 2007.1 The goals were to prevent unintentional poisonings from unused and/or expired drugs in the home, prevent misuse and diversion of discarded drugs, and to keep drugs within engineered landfills, instead of in the water supply. The means suggested were simple:
- Mix unused drugs with old coffee grounds or kitty litter, or something else that no one would be tempted to swallow.
- Place this material in a container or zip-top plastic bag.
- Discard the container with household trash.
The old recommendation of flushing drugs down the toilet or drain is no longer advised. Exceptions are for extremely toxic drugs and controlled substances which may be exceptionally unsafe if swallowed unintentionally, taken in overdose, or abused; the most common example is narcotic drugs.2
How do drugs and personal care products enter the water supply?
Even if all consumers followed these recommendations, there are many ways for drugs and personal care products to enter the water supply. Examples include:
- Drugs and their breakdown products that are eliminated in urine and feces and flushed down the toilet, thus entering the water supply through sewage systems or as leachate from inadequate or leaking septic fields.
- Drugs that are eliminated through the skin and personal care products applied to the skin, that then are washed down the drain.
- Drugs and personal care products that spread onto clothing; when the clothing is washed, the chemicals go down the drain.
- Drugs from health care facilities that may not be legally required to discard drugs as hazardous materials, for example, long-term care facilities, medical and dental offices, and veterinarians.
- Sewage/waste water from hospitals and other health care facilities, from which human waste is flushed or washed down the drain, just as it is at home.
- Drugs from animal feeding operations and ranches.
- Domestic animal waste.
- Illicit drugs.
- Waste water treatment plants that do not filter all drugs, potentially releasing drugs into the drinking water, water used for irrigation,3 and/or into the sludge that may be used to fertilize food crops.4
- Storm water overflow, during which water bypasses waste water treatment plants.
- "Straight-piping", i.e. direct release of untreated sewage into bodies of water.
What drugs are found in drinking water?
The Associated Press compiled a list of pharmaceuticals found in tap water in several areas around the country. These compounds were identified in tests conducted by federal government agencies and individual water providers. Among the drugs that were found in tap water were acetaminophen, caffeine, antibiotics, antidepressants, anticonvulsants, antihistamines, non-steroidal anti-inflammatory drugs, steroids, and female sex hormones.5 The study notes that water companies are not required by the federal government to test their water for pharmaceuticals, many water companies do not routinely test tap water for these compounds, and most companies do not make test results generally available.
The U.S. Environmental Protection Agency (EPA) reported that, in addition to steroids and antibiotics, more than one hundred pharmaceuticals and personal care products have been identified in drinking water and other environmental samples.6 In a pilot study of fish from five sites near wastewater treatment sites and a control site in a non-polluted area, seventeen pharmaceutical compounds were found in fish from the five streams, including antidepressants and an antihistamine, but not in fish from the control site.7
The U.S. Geological Survey collected drinking water samples from ground-water and surface-water sites in half the U.S. states. Chemicals found included metabolites of nicotine and caffeine, bisphenol-A, fire retardants, and a number of pharmaceuticals.8
In an earlier study by the U.S. Geological Survey of 139 streams in 30 states, researchers assessed the water for the presence or absence of 95 chemicals. One or more was detected in 80 percent of the streams. Eighty-two of the 95 chemicals tested for were found at least once. In addition to pharmaceuticals, researchers found triclosan, used as an antimicrobial/disinfectant in consumer products; DEET, used in insect repellants; fire retardants; detergents; and plasticizers.9
Government and industry researchers note, though, that the chemicals are found in minute amounts. For as long as humans have ingested, injected, inhaled, or applied drugs and chemicals, these substances and/or their metabolites most likely have been entering the environment. Many or most of them are being identified now because testing has become increasingly sensitive. In other words, an unknown number of substances may have been present in water for some time, but it's only recently that technology existed to measure such small quantities.10 Some question whether drugs found in amounts as low as parts per billion, or parts per trillion, are even capable of causing harm, as these amounts are far lower than therapeutic doses.11
Is aquatic life affected?
A number of pharmaceuticals and personal care products have been measured in tissue of aquatic species in the U.S. For example, fish exposed to wastewater from a metropolitan area sewage treatment plant exhibited endocrine disruption, i.e. male fish produced female egg-yolk proteins.12 In a widely reported study of smallmouth bass from the Potomac River, male fish were found to have female ovarian tissue within their testes.13 Studies of pharmaceuticals and other contaminants have been conducted in many countries and have included insect and aquatic life as targets, with many types of alterations found in structure and function. No one believes that the presence of human drugs and other products is desirable in water and wildlife. Even so, it can be a challenge to ascribe some changes in aquatic life and other wildlife to the presence of drugs, personal care products, and other substances in the water if the baseline incidence of a particular abnormality is not known for comparison.
Are there implications for human health?
To date, no studies implicate chemicals in water with human health problems. There are concerns for a number of reasons, however.
- As testing becomes more sensitive, we may learn that even more drugs, personal care products, and other contaminants are in the water that we use for drinking and recreation.
- It is not known if exposure to chemicals in drinking water poses a hazard for pregnant women and their fetuses. It is theoretically possible that a woman may be ingesting drugs that are contraindicated in pregnancy. Also, it is not known if continual exposure to low or trace levels of these substances has an effect on the woman or developing infant.
- It is theoretically possible for someone to ingest a drug to which he or she is allergic.
- Drug resistance is a theoretical issue, if someone is regularly ingesting measurable, even though tiny, amounts of a drug over a period of time.
- Studies of potential health risks are typically carried out with one drug or substance at a time. It is not known what, if any, problems may occur with life-long ingestion of ever-changing combinations of drugs and chemicals.
Even with these potential concerns, the U.S. water supply is considered safe, based on current knowledge. EPA asserts that U.S. drinking water is among the safest in the world.14 (EPA notes that there are more than 155,000 public suppliers of drinking water in the U.S. and provides information for researching the quality of water in individual communities.15)
What is being done to monitor for and eliminate pharmaceuticals and personal care products from water?
Existing research regarding environmental pollutants is voluminous. Research is ongoing in several areas, for example:
- Determining how various health care facilities manage unused pharmaceuticals.16
- Measuring substances in water17, 18 and elsewhere in the environment.19
- Assessing the potential toxicity of pharmaceuticals and other substances to aquatic life, wildlife, humans, and the environment.
- Determining the environmental fate of pharmaceuticals, personal care products, and other chemicals as they enter the waste stream.
- Preventing such substances from entering the environment.
- Determining how best to strengthen the infrastructure of the nation's water system, including upgrading water treatment plants to prevent contaminants from entering the drinking water supply; eliminating failing septic systems; and preventing contaminants from reaching aquifers from landfills.
What is being done now to eliminate drugs and personal care products from the water supply?
The EPA is considering more than 100 chemicals, including pharmaceuticals, for inclusion in regulations under the Safe Water Drinking Act. Also, the U.S. Department of the Interior is funding water infrastructure improvements.20
There are requirements that pharmaceutical companies and other industries discharge only treated water. Depending on the geographic area, there may be local regulations for agricultural and animal management that address environmentally sound disposal of animal waste and pesticides. Many health care facilities contract with disposal firms to discard unused pharmaceuticals in an environmentally sound manner. Community pharmacies and law-enforcement organizations sometimes sponsor community "drug take-back" programs, allowing consumers to turn in drugs that then will be disposed of safely, according to relevant hazardous materials guidelines. Water infrastructure improvements to limit or eliminate the number of substances released into drinking water are desirable but would be very expensive.
What can consumers do?
It would be ideal if drugs and personal care products, along with pesticides and other chemicals, never reached the water supply. Realistically, achieving this goal would require massive resources and cooperation among academic, private, and government entities. No one is advising consumers to stop taking needed medicines, using sunscreen and insect repellants, or medicating their pets as needed. Every consumer, though, can take individual steps to limit introduction of drugs and personal care products into the water supply.
- Buy only drugs and products that are needed.
- Buy the minimum quantity needed. Purchasing a "giant size" bottle of medication that cannot be used up before expiring is wasteful; unused drug can enter the water supply when discarded.
- Take only the prescribed or recommended amount of needed drugs.
- Apply skin care products according to label instructions.
- Ask your physician for drug samples, if they are available and appropriate for your condition, before filling a prescription that might not work for you. (Be sure all drug samples are stored safely, out of sight and reach of children.)
- If you have unused prescription medicines, ask your pharmacy if they will take them back for disposal. If not, find out if they know of drug take-back programs in your community.
- If drug take-back programs are not available to you, carefully follow federal guidelines for disposal of unneeded and expired drugs.
- If you have a septic tank/field, be sure that it is maintained properly to eliminate leakage of pharmaceutical and personal care product waste into groundwater.
- Clean up pet waste promptly.
Rose Ann Gould Soloway, RN, BSN, MSEd, DABAT emerita
For More Information
The basic science research in this field is voluminous. Some targeted studies may be identified from the bibliographies within the web sites and references listed in the "Reference" section.