Ask Dr. K: Don’t flush your unused drugs down the drain

Drugs can get into the water in a variety of ways. Many people flush unused or expired drugs down the toilet or pour them down the drain. Some nursing homes and hospitals do the same. Drug manufacturing facilities contribute to pharmaceutical pollution. Agricultural waste, from poultry and livestock given antibiotic- and hormone-laced feed, is another major source.

Sewage treatment plants and water treatment facilities are not designed to remove pharmaceuticals from water. As a result, some pharmaceutical pollution does wind up in the water we drink. So far, only trace amounts of drugs have been found in drinking water, far below levels thought to affect humans.

It’s possible that ingesting even tiny amounts of these drugs could, over time, affect our health. But for now, there’s no evidence that drugs in the water are harming us.

The drugs we pour down the drain, however, could be affecting fish. For example, water sources polluted with estrogen and estrogen-like chemicals (from birth control pills and hormone treatments) contain more fish who have both male and female characteristics — when they should have only one or the other. The impact of this on fish breeding is unclear.

New guidelines encourage responsible drug disposal for hospitals and nursing homes. And we can do our part as well:

— Limit bulk purchases. Big bottles of expired pills are more likely to end up in the water.

— Do not flush unused medicines or pour them down the drain. This is the most basic thing that we all can, and should, do.

Instead, throw medications into the trash. Medications disposed of this way are incinerated or buried in landfills. This isn’t ideal, but it’s preferable to flushing or pouring them down the drain.

— Better yet, use drug take-back programs. These programs allow you to drop off unused medications at specified locations in your community. Drug take-back programs are organized by state and local governments and also by private institutions, including pharmacy chains.

I learned from a colleague that the most recent such government program provided pickup spots in nearly 6,000 locations around the United States. In total, nearly 3 million pounds of outdated or unused pharmaceuticals have been safely disposed of through drug take-back programs.

While we don’t know of any harm to humans from the current low levels of old drugs in our drinking water, the truth is that we can’t be sure there is no harm. That’s why I urge my patients to use these programs. It’s just one of many ways to be a good citizen — not just to your fellow human beings, but also to fish!

Dr. Anthony L. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.