CINCINNATI (AP) — E-cigarettes keep popping up for sale at county jails around the country even as some government officials, schools and health experts urge tighter control over the devices, especially in public buildings.

The increasingly popular electronic cigarettes are showing up at jails where officials say they have seen benefits from selling the devices. They say e-cigarettes calm agitated inmates, who aren’t allowed in most jails and prisons to use tobacco-burning cigarettes.

Jail officials say e-cigarettes also reduce instances of smuggled-in traditional cigarettes and loose tobacco. And the additional revenue from the sales can be used to buy uniforms, food and other inmate supplies at a savings to taxpayers.

Still some law enforcement officials and others raise ethical questions and worry about potential health risks.