Washington ? Tanning lamps can double the risk of some common types of skin cancer, particularly for the young, according to researchers who suggest that tanning salons should be closed to minors.

In a study to appear today in the Journal of the National Cancer Institute, researchers found that people who used tanning devices were 1.5 to 2.5 times more likely to have common kinds of skin cancer than were people who did not use the devices.

The study confirmed what doctors and other health care workers have long suspected  that sun lamp use increases the risk of basal cell and squamous cell skin cancers, said Margaret R. Karagas, first author of the study.

“Even though we suspected tanning lamps might cause these types of skin cancers, there really hadn’t before been epidemiological studies that addressed that issue,” she said.

Dr. James Spencer, vice chairman of the department of dermatology at Mount Sinai Hospital in New York and an expert spokesman for the American Academy of Dermatology, praised the study as confirming in humans what has already been shown in animal studies  “it is actually worse to go to the tanning parlor and get a little bit each day” than it is to get an infrequent sunburn.

Both can seriously damage the skin, he said, but the small, day-to-day exposure is worse for the skin in the long run. “The tanning industry has said … as long as you don’t burn you’ll be OK,” he said. “This study shows that this is not true.”

Joseph Levy, vice president of the International Smart Tan Network and a spokesman for the Indoor Tanning Assn., however, said the study “is not an indictment of commercial tanning facilities in any way.”

He said that occasional sunburn “is a risk factor in all forms of skin cancer and intermittent sunburn is what the tanning industry is trying to stop.”

About 1 million Americans are diagnosed annually with skin cancer. About 80 percent are basal cell; 16 percent squamous cell, and 4 percent are melanoma, the most serious form of skin cancer. Melanoma patients were not included in the study.