Construction workers are dying from opioid overdoses across the country, both because they are often forced to work hard jobs through the pain of injuries in order to provide for their families—and because there is money to be made off their pain.

A recent report from the Massachusetts Department of Public Health shows that people working in construction are six times more likely to die an opioid-related death than all other workers in the state. That means nearly a quarter of all people who died from opioid overdoses in Massachusetts, a state with one of the highest overdose rates in the country, were employed in construction.

Elsewhere in the country, overdose death rates for construction workers are even higher. In Ohio, they are seven times more likely than other workers to die from an overdose in 2016, according to an analysis by The Plain Dealer. That’s roughly the same rate the Midwest Economic Policy Institute found across the entire Midwest—which also includes Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin.

The lethal link between construction work, pain, injury, and powerful painkillers is no mystery to researchers or people in the industry. In one study, 75 percent of workers said they were recently dealing with musculoskeletal pain and four out of ten said they’d been injured in the month before.

“You get injured at work, you get a prescription for that injury that potentially develops into some sort of misuse, or if you don’t get a prescription maybe you move onto getting the drugs some other way,” explains Devan Hawkins, one of the authors of the Massachusetts study and an instructor of public health at the Massachusetts College of Pharmacy and Health Sciences.

Those injuries are not necessarily dramatic emergencies but the daily grind of, say, lifting 3.8 tons of bricks day-in and day-out. Working in construction is a taxing job that leaves 40 percent of its older workers with chronic back pain. “It’s not only about injuries, it’s also about pain,” says Hawkins. “There is a high prevalence of pain among construction workers just to be able to do this sort of work.”

Robert Hollis, a roofing contractor from Plymouth, Massachusetts, died of an opioid overdose at age 30 in 2016. “It wasn’t like he fell,” says his father Bob Hollis, who opened Plymouth Recovery Center after his son died. “It’s not falls. Because of the nature of the work, it becomes chronic pain over time.”

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One hypothesis is that chronic pain is made worse because workers may not be able to take time off when they’re hurt without risking their jobs. States including Iowa, Illinois, Indiana, and Wisconsin don’t have paid sick leave, while Massachusetts requires companies with ten or fewer employees to provide only unpaid sick leave. That may be why some people take an opioid—to get through the day and work through the pain.

“When you are in these jobs, people are working through pain. They need to keep their job, and cannot afford not to go to work and cannot afford to be in pain,” explains Vaira Harik, senior project manager at the Barnstable County Department of Human Services, who has studied overdose deaths in Cape Cod.

While construction workers have some of the highest uninsured rates of any industry, union construction workers are much more likely to have health insurance and collective bargaining agreements that include sick days. For example, the International Union of Operating Engineers Local 150—which covers Northern Illinois, Northern Indiana, and Southeastern Iowa—has a collective bargaining agreement that gives their workers one day of paid sick leave for every month worked. “There is anecdotal evidence that the [overdose] problem is less pervasive on the union side,” says Jill Manzo, Midwest researcher at the Illinois Economic Policy Institute and coauthor of the study on the opioid epidemic across the region.

But it’s difficult to know how many people are working in the construction industry without such protections. “There are many who work off-book,” or under the table, says Marjorie Bowman, a physician and professor of family medicine at Wright State University in Dayton, Ohio, who has written about treating people with opioid addiction. “Some of the things we can do to help patients are not easy for people who do not have good insurance, who work off book, whose bosses don’t follow the rules about hours, and who frequently switch jobs.”

What we know for sure is that construction workers are being prescribed massive amounts of pharmaceuticals in order to deal with the pain: In 15 states, more than 70 percent of workers’ compensation claims in the construction industry involved opioids and 20 percent of all prescription drug spending in the industry is for opioids, about 5 to 10 percent higher than other industries.

Lawsuits against pharmaceutical companies filed across the country give as an example the way Opana ER—an extended-release opioid painkiller that the FDA wanted off the shelves in June 2017 because of the potential for abuse—was marketed by Endo Pharmaceuticals for treating construction workers specifically.

An archived webpage for Opana ER includes this patient profile:

Bill has to find a pain medication that allows him to keep working

Hello, my name is Bill and I am a 40-year-old construction worker who developed low back pain. I have been on pain treatment for several months for my severe, chronic low back pain, my doctor keeps increasing my current medication but the pain still remains.

It is important that whatever types of pain medication my doctor suggests that I am still able to continue work to support my family.

Are you like Bill? Talk to your doctor to find out if OPANA ER is an appropriate choice for your moderate to severe chronic pain.

Endo did voluntarily take Opana ER off the market a month after the FDA’s request in 2017. When reached for comment, the company responded with this link to its “open letter on the opioid abuse crisis.”

In April, the Teamsters’ Health and Welfare Funds in West Virginia and Ohio filed a lawsuit against multiple pharmaceutical companies, including Endo Pharmaceuticals, pointing to the high risk of overdose for people in construction and alleging “false advertising targeted workers in physically demanding jobs, like construction.” “This is not random,” they argue.

Jodi Sugerman-Brozan, executive director at the Massachusetts Coalition for Occupational Safety and Health, which has been trying to make construction work safer and less painful, agrees. “This is a man-made epidemic,” Sugarman-Brozan says. “Now, we are paying the price.”