Delta Air Lines announced that it would replace uniforms for tens of thousands of employees after months of pressure and two lawsuits from workers who said the garments made them sick.

The company announced the change in an email to employees, saying that despite the company’s efforts to create an alternative to the uniforms it rolled out in 2018, it has “not been able to resolve this situation for everyone,” according to a release from the Association of Flight Attendants-CWA, a union working to organize flight attendants at the company.

Delta had rolled out the new uniforms, designed by fashion darling Zac Posen, to great fanfare in 2018, swapping the company’s trademark blue look for a purple, gray and red palette. The uniforms were for its more than 60,000 employees, including flight attendants, airport agents, mechanics and fleet service agents. The company said the uniform switch had been years in the making and included audits of the clothing manufacturer, Lands’ End.

But a group of more than 500 employees say that they began to suffer issues soon after the uniforms were introduced.

In a class-action lawsuit filed in federal court against the clothing maker in December, the group says chemical additives to give the uniforms high-stretch, wrinkle-free and stain-resistant properties have resulted in a wide variety of health problems, including respiratory issues, headaches, fatigue, blurred vision, and rashes, hives and other skin inflammation. The lawsuit contends Delta self-reported that 1,900 of its employees had concerns about the uniforms by the middle of 2019 and that the number of employees injured by the uniforms is “significantly higher.”

Delta says it sent the uniforms for testing at three laboratories and all found that they were safe.

The decision to swap out the uniforms comes as union campaigns heat up at Delta.

Two major unions have been working to organize the company’s workers. The campaign by the International Association of Machinists and Aerospace Workers to organize about 44,000 flight attendants and ramp workers drew headlines and attention from Democratic heavyweights such as Sens. Bernie Sanders (I-Vt.) and Sherrod Brown (D-Ohio) after photos of the aggressively anti-union posters the company was using began circulating on social media.

“We applaud this step in the right direction, but encourage Delta management to take additional actions as soon as possible for the health of all Flight Attendants and to repair the damage caused for individuals,” the union said in a statement.

A federal watchdog, the National Institute for Occupational Safety and Health, evaluated the uniforms in 2019, finding that it was “possible” that chemicals in the uniforms were causing skin symptoms among employees. In their court complaint, the workers said tests they did of the garments found the presence of chemicals and heavy metals such as chromium, antimony, mercury and formaldehyde.

“While our uniforms are safe it is clear that there are a number of people who have lost confidence in the uniform and it is in part that reason why we are making a change to our program,” said Delta spokesman Anthony Black. The switch will cost the company millions of dollars, he said.

In its statement to employees, the company said that in addition to letting workers wear black and white, it will roll out new shirt, blouse and suit options for employees in the spring before the new uniforms are ready in 2021. The new uniforms will be certified to meet Standard 100 requirements to be free from harmful substances from the testing consortium Oeko-Tex.

Lands’ End said it looks forward to continuing to work with Delta.

“Health and safety are paramount to us, and that’s why we require compliance with restricted substance lists and other applicable regulations and laws throughout the manufacturing process, and why each uniform we supply undergoes rigorous testing at independent labs to ensure that the garments meet or exceed the strictest global standards,” the company said in a statement distributed by spokeswoman Rosalind Drisko.

Other airlines have faced similar health complaints about their uniforms in recent years, including American Airlines and Alaska Airlines.

The AFA blames the issues on global trade agreements like the North American Free Trade Agreement and China’s entry into the World Trade Organization in 2001, which have resulted in the loss of domestic clothing production.

“The globalization of the garment industry has created enormous challenges for quality control,” the union said in a video.

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