What to do with worn out AAA batteries from your TV remote or the spent battery from a watch? We often hear that it is safe to dispose of such single-use (primary) batteries with regular household trash. However, button batteries can contain toxic chemicals like mercury, which helps explain why the State of Maine states that they “should NOT go in the trash.” And since single-stream batteries contain valuable metals, recycling them represents the most sustainable choice.

Button batteries power everything from watches to hearing aids. They derive their name from their shape and come in a dizzying array of sizes. A code consisting of letters and numbers designates each size (see labideal.com/coin-cell-button-cell-battery-guide/). Other common single-use batteries include the alkaline and lithium types used for flashlights, toys, smoke detectors and so forth. Most are cylindrical, such as AA, AAA, C, D, though the 9V size is shaped like a tiny brick.

Disposing of single-use batteries can be problematic, so try to limit the number you buy. Battery life depends on many factors, but in general you get what you pay for. So if you can, purchase name brand batteries rather than generic or store brand batteries. You will pay more up front but benefit from longer-lasting batteries. Be sure to care for your single-use batteries too. Some devices can slowly draw down battery power even when not in use. Thus, by removing them from the device when not using it — and storing them in a dry environment at room temperature — your batteries should last longer.

Once single-use batteries lose their charge, there are only a few safe disposal alternatives in the Brunswick-Topsham area. The Staples in Brunswick accepts single-use batteries for recycling. You can also drop them off at Riverside Recycling in Portland for 75 cents per battery. Another option is to send depleted single-use batteries—along with a payment—to a battery recycling service like Call2Recycle, call2recycle.org/store/. Clearly we need to press our local, state, and national legislators to increase the accessibility of single-use battery recycling — and reduce the cost.

David Conwell is a former teacher and member of Brunswick’s Sustainability Committee.