An American mother with a passion for tanning has pleaded not guilty in court to a charge of child endangerment for allegedly allowing her five-year-old daughter into a tanning booth.

Authorities say Patricia Krentcil's daughter, now six, turned up at her elementary school in Nutley, New Jersey, with sunburn, prompting a school nurse to contact police.

But Ms Krentcil insists that, although her daughter was in the room, she was not in the tanning booth itself.