I read that prescription medications have been detected in some community water supplies. Will a home water filter remove them from tap water? —S.M., Washington, D.C.

It might, depending on the drug. Tests of water samples from around the country have found numerous drugs, including antibiotics, hormones, and medications for cholesterol and blood pressure. The levels were minuscule, and it’s not clear what health risks they may pose. It’s also not clear how effectively a water filter—either the kind that attaches to the kitchen sink or a whole-house model—might remove them, since we couldn’t find any independent studies testing them for that purpose. But in theory, our experts say they’d probably filter out at least those drugs that dissolve into particles of similar size to the ones the filters are known to remove, such as chlorine and pesticides.

Take a look at 10 ways to reduce your exposure to chemicals and read more on how to safely dispose of unused medications.