Nail salon workers in New York City face greater health risks on the job than previously understood, according to a new study published in the journal Risk Analysis.
Researchers found that chemical concentrations spiked repeatedly throughout the workday, revealing short-term exposure peaks that traditional full-shift averages may overlook. These peaks could have important implications for worker health.
Researchers tracked air quality minute-by-minute for a week in five New York City nail salons and found that levels of volatile organic compounds (VOCs) varied widely. The study, led by A. Michael Ierardi, PhD, CIH, at the City University of New York Graduate School of Public Health and Health Policy (CUNY SPH), combined continuous photoionization detector monitoring with chemical specific sampling using thermal desorption tubes.
The VOC mixtures were largely composed of fast-evaporating solvents commonly used in nail products, with other potentially more hazardous compounds, like methacrylates and benzene, detected less frequently and at lower concentrations. However, although benzene levels were low, modeled lifetime cancer risks exceeded the EPA's 1‑in‑1‑million benchmark in several salons under certain exposure scenarios. Noncancer hazard estimates were generally below the benchmark, with upper bound estimates exceeding it in the salon with the highest measured VOC concentrations.
Occupational exposure limits are generally set to protect healthy, non-pregnant adult men during a standard eight-hour work shift. Researchers say these limits may fall short for more vulnerable groups, including women of reproductive age who make up much of the nail salon workforce. Additionally, full-shift averages do not fully capture short‑term peaks, which could contribute to acute symptoms, although this study did not specifically assess symptoms or identify the sources of individual peaks. Overall, the findings support incorporating peak‑based metrics alongside full‑shift averages when evaluating nail salon exposures.
Key Findings
The most commonly detected chemicals were ethyl acetate, acetone, n-butyl acetate, and methyl acetate, all fast-evaporating solvents used in products like nail polishes and removers. These were generally identified at higher levels than xylenes (mixed isomers), methyl methacrylate, benzene, and ethyl methacrylate. Methacrylates are associated with artificial nail products, while benzene may be present in some nail products at low levels.
Benzene was detected in salon air at low concentrations, but estimated lifetime cancer risks associated with exposure still exceeded the EPA's 1-in-1-million benchmark in several salons.
Nail care is an $8 billion industry in the U.S., and its workers spend prolonged shifts breathing in complex mixtures of chemicals released by nail salon treatments and products. These include solvents (e.g., acetone, ethyl acetate), aromatic hydrocarbons (e.g., toluene, xylenes), and methacrylates used in artificial nail applications. These compounds are associated with a range of acute and chronic health effects, including eye, nose and lung irritation, central nervous system effects, and reproductive harm. The results indicate that employees repeatedly exposed to these chemicals are at a greater risk for both cancerous and noncancerous health outcomes than current data suggests.
"This research shows that traditional air sampling and risk assessment methods don't tell the whole story for nail salons," said Dr. Ierardi, an occupational and environmental health and safety scholar and research assistant at CUNY SPH. "Nail technicians and other salon employees may be exposed to high, intermittent peaks of airborne chemicals throughout the workday, yet the health impacts of those exposures have been underestimated. Recognizing the limitations of existing approaches and methods is an important first step toward better understanding health risks and protecting nail salon workers."
