Isopropyl acetone, methyl ethyl ketone, and n-methyl-pyrrolidone, are commonly used as the solvent in nail polish removers. Evidence suggests that these chemicals may cause reproductive harm and organ toxicity. They are a serious concern for nail salon workers and pregnant women.

FOUND IN: Nail polish removers

WHAT TO LOOK FOR ON THE LABEL: Isopropyl Acetone: Methyl isobutyl ketone (MIBK), hexone, 2-pentanone; Methyl Ethyl Ketone (MEK): 2-butanone, 3-butanone, acetone; N-Methyl-Pyrrolidone (NMP): n-methyl-2-pyrrolidone, 1-methyl-2-pyrrolidone

WHAT CHEMICALS ARE USED IN NAIL POLISH REMOVERS? Isopropyl acetone, MEK, and NMP are all solvents used in nail polish removers. MORE...

Isopropyl acetone is also a ketone used in lacquers. MEK is mainly used as a solvent in application of protective coatings and adhesives and in food processing. It is also a common ingredient in varnishes and glues. NMP has many purposes including stripping paint, removing graffiti, laboratory reagents, insecticide/fungicide/herbicide products, and pharmaceutical solvents. NMP’s main modes of exposure include inhalation and dermal pathways.

HEALTH CONCERNS: Irritation of the skin, eyes and lungs; organ toxicity and cancer. MORE...

Isopropyl Acetone: Studies conducted on humans exposed briefly to isopropyl acetone experienced respiratory and/or eye irritation, headache or nausea. , In a long-term study of occupational exposure, 19 workers were exposed to isopropyl acetone for 20-30 minutes per day for five years. More than half of the workers complained of headache, eye irritation, nausea, sore throat, and weakness. A few workers had heartburn, insomnia, and intestinal pain. After five years, the amount of isopropyl acetone in their work environment decreased by approximately 75% and for all except for two workers, their previous symptoms disappeared.
Isopropyl acetone may also lead to organ toxicity, particularly of the kidneys. In two studies conducted on rats, those exposed to isopropyl acetone developed non-cancerous lesions on their kidneys, This effect was more severe and pronounced in male rats, though female rats also had increased incidence of mild kidney disease. In addition, isopropyl acetone is potentially neurotoxic due to the presence of methyl n-butyl ketone (a known neurotoxin) as an impurity.
One study linked isopropyl acetone to renal tubule carcinoma and/or adenoma.

Methyl Ethyl Ketone: Human occupational studies point to the possibility of MEK as a neurotoxin. A study of 41 factory workers exposed to MEK noted that workers experienced headaches, memory difficulties, and irritability. Workers also reported eye irritation, respiratory tract irritation, and muscular and joint pains. A study of exposed shoe factory workers also found neurological symptoms; workers suffered from headaches, chest pains, sleep disorders, dizziness, and drowsiness. Data gaps remain regarding the extent of exposure in both studies.

A study of aircraft workers exposed to MEK and other solvents found that women with higher exposures of MEK had elevated risks for multiple myeloma, although the results were not statistically significant. Furthermore, workers were exposed to multiple solvents, which make efforts to solely attribute increased mortality to MEK difficult. Pregnant rats exposed to MEK showed decreased weight gain and skeletal malformations were found in their offspring. These studies support the connection between MEK and developmental toxicity.

N-Methyl-Pyrrolidone: California’s Proposition 65 identifies NMP as a reproductive toxin. Pregnant rats exposed to NMP have increased incidence of maternal toxicity, including symptoms such as fewer live fetuses per rat and decreased weight gain and food consumption. Furthermore, the offspring of the NMP-exposed rats were more likely to develop internal and external malformations and have lower birth weights. After birth, these offspring suffered from delayed physical development, struggled with completing spatial tasks and had lower body weight. Other studies have also found lower birthweights in the offspring of NMP-exposed rates, although in some studies the effect either normalized over time, or had no impact on later development.

In humans, NMP has been reported to induce acute contact dermatitis, with symptoms such as swelling and itching. NMP is able to penetrate latex easily, and thus produces these skin reactions even in workers wearing latex gloves. NMP is also a severe eye irritant that can cause headaches at exposure levels as low as 0.7 ppm in the air for 30 minutes.

VULNERABLE POPULATIONS: Nail salon workers, pregnant women

REGULATIONS: Isopropyl Acetone is restricted to low doses in workplace environments in the European Union. The US Occupational Safety and Health Administration limits the amount of Methyl Ethyl Ketone that workers can be exposed to in an average workday. N-Methyl-Pyrrolidone is prohibited for use in cosmetics in the European Union due to links to cancer, mutagenicity or reproductive toxicity. It is also listed on California’s Proposition 65 list of known chemicals to cause cancer, birth defects, or other reproductive harm.

HOW TO AVOID: Consumers can choose nail polish removers without these chemicals. Nail salon workers and owners should follow through with protective actions such as committing to adopting safer nail products, wearing nitrile gloves, installing appropriate ventilation, and training all staff on safety procedures.

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