It's difficult for hairdressers to complain about ill health or even ask coworkers to do the treatments when they aren't around. Money is a huge incentive – they charge up to $350 a pop. Health insurance is almost nonexistent, and worker protection is scarce. Many stylists in salons rent space and are self-employed, outside the purview of some OSHA protections.
“Everyone is so scared to speak up, it's ridiculous,” said Larissa Tanev, who works at a salon in Bellevue, Wash. “Look how far we've come with cigarette smoke. How can this be happening?”
Dangers of formaldehyde
Billions of pounds of formaldehyde are produced every year to make adhesives and binders for wood products, pulp and paper products, plastics, synthetic fibers and textile finishing. Formaldehyde also is used as a disinfectant, biocide and embalming solution. In consumer products, it works as a preservative.
Thousands of factory and funeral home workers have been subjects of epidemiological studies worldwide that have linked formaldehyde to health effects. It can irritate eye, nose and throat tissues, triggering asthma or other respiratory problems and creating a heightened allergic reaction to other substances.
Last year the U.S. National Toxicology Program classified formaldehyde as a known human carcinogen. An international panel had advanced it to that highest risk category in 2004.
“Formaldehyde has been shown in both humans and lab animals to cause structural and numerical changes in their chromosomes, which are associated with increased cancer risk, particularly with leukemia. But the exact biological mechanisms for that are not well understood,” said Luoping Zhang, a toxicologist in the University of California, Berkeley School of Public Health.
Workers in Chinese factories exposed to high levels of formaldehyde had lower counts of white blood cells that fight germs and diseases, according to a 2010 study led by Zhang. The cellular changes in the workers reflected toxicity in the bone marrow, a sign of leukemia, she said.
Several U.S. studies of workers exposed to formaldehyde have reported a greater risk of leukemia and other cancers than in the general population.
Funeral workers who had performed the most embalming and those with the highest estimated formaldehyde exposure had the greatest risk of myeloid leukemia, according to a National Institutes of Health study published in 2009. A link to leukemia also was found in a study of more than 11,000 U.S. textile workers exposed to formaldehyde.
A National Cancer Institute long-term study, involving 25,619 industrial workers in 10 factories that produced or used formaldehyde, found an increased risk of death due to leukemia, particularly myeloid leukemia, and higher rates of nasal-pharynx cancer. Further examination of the same workers, with ten more years of data, continued to show a possible link to leukemia, as well as lymphoma and multiple myeloma, among those with the highest exposures. But it found no higher risk for workers with average or cumulative exposures.
Some scientists have called the evidence in those studies weak, saying there is insufficient data to prove a link between leukemia and formaldehyde. A British study of industrial workers found no association to exposures.