A typical salon manicure involves drying freshly painted nails under a lamp that emits ultraviolet-A (UV-A) rays -- a spectrum of light long linked to skin cancers. But a new study suggests that the average visit to a nail salon carries little carcinogenic potential. "Considering the low UV-A energy exposure in an average manicure visit, multiple visits would be required to reach the threshold for potential DNA damage" that might spur cancer, wrote a team reporting their findings April 30 in JAMA Dermatology. In the study, researchers led by Dr. Lyndsay Shipp of the department of dermatology at Georgia Regents University, in Augusta, say that prior studies into the use of UV-emitting nail polish drying lamps have not had sufficient rigor to come to any reliable conclusions. In their study, Shipp's team used high-tech meters to measure the UV-A light exposures upon hands held in various positions under 17 different types of drying lamps. The researchers conducted the study at 16 nail salons. First of all, they said, there were "notable differences" in the amount of UV-A light emitted by the various devices, and the amount of exposure to the hands also varied depending on the positioning of the device. Overall, a single nail polish drying session under one of the lamps would not expose a person to a potentially cancer-causing amount of UV-A light, Shipp's team said, and "even with numerous exposures, the risk for carcinogenesis remains small." Still,... |
Los Angeles has again topped a list of the cities with the worst smog in the nation, violating federal health standards for ozone an average of 122 days a year.
The annual air pollution rankings, being released Wednesday by the American Lung Assn., were dominated by the Los Angeles Basin and California's Central Valley, which despite vast improvements over the last few decades still have the nation's highest levels of ozone and fine particle pollution.
"Air pollution is not just a nuisance or the haze we see on the horizon; it's literally putting our health in danger," said Bonnie Holmes-Gen, senior policy director of the American Lung Assn. in California. "We've come a long way, but the status quo is not acceptable."
The report evaluated metropolitan areas based on recorded levels of ozone, the main ingredient in smog, and conducted a separate analysis of fine particles — or soot — the microscopic pollutants that tend to build up in colder, winter months.
The Los Angeles region ranked fourth among metropolitan areas nationwide for short-term spikes in fine particle pollution, coming in behind Fresno, Visalia and Bakersfield. The L.A. Basin tied for third with Bakersfield for annual fine particle concentrations.
The nonprofit advocacy group's "State of the Air" report derives its rankings from publicly reported measurements of ozone and fine particle pollution from official monitoring sites. Analysts used data from 2010, 2011 and 2012 and...