In April, the federal Occupational Safety and Health Administration (OSHA) issued a hazard alert, warning that formaldehyde-containing hair-straightening products can cause serious health problems, including increased risk of cancer.
Across the country, hair salon workers and customers have complained of acute reactions such as hair loss, nose bleeds and breathing problems.
"This is a dramatic example of why we urgently need to close the gaping holes in the outdated federal law that allows hazardous chemicals in cosmetics products," said Jan Schakowsky, Illinois Congress representative, who signed the letter.
"That's why I'm planning to re-introduce the Safe Cosmetics Act, legislation which will ensure that cosmetics do not contain harmful ingredients."
Formaldehyde may cause cancer
Last month, the National Academy of Sciences released its report confirming the Environmental Protection Agency's determination that formaldehyde causes cancer in humans.
"Workers and consumers have the right to know the risks of these products and how to protect themselves," said Lisa Archer, director of the Campaign for Safe Cosmetics at the Breast Cancer Fund.
"It's clear that we need a better safety system, where products are assessed for safety before they cause harm."
Under current US law, the FDA cannot require product recalls, but can issue a voluntary recall.
"Our investigation into the misleading claims and horror stories of this industry shows that this federal action cannot come soon enough," said Jane Houlihan, Environmental Working Group's senior vice president of research.
"We applaud these members of Congress for speaking out on behalf of scarred customers and anxious salon workers who need stronger safe-guards against dangerous chemical ingredients in these hair straighteners. Known and probable human carcinogens should never be allowed into products we breath in and apply to our bodies."
As a result of the risks posed by these types of salon treatments, six countries have recalled the use of formaldehyde-based straighteners, however, the FDA has yet to issue a voluntary recall.