In July, a mail carrier in Phoenix, Arizona, claimed to have cooked a steak to an internal temperature of 142 degrees Fahrenheit—medium rare—on the dashboard of his delivery vehicle, which doesn't have air conditioning.

While it's fine for your credit card bills and other mail to get that hot, when medications are exposed to temperatures outside the range specified by manufacturers, called “temperature excursions,” they could lose their potency. For birth control pills, this could increase the chances of unplanned pregnancies.

The FDA-approved labels for common birth control formulations like Yasmin, Ortho Tri-Cyclen Lo, and Sprintec say that the pills should be stored between 68 and 77 degrees Fahrenheit, with excursions permitted up to 86 degrees. The Arizona steak got more than 50 degrees hotter than that.

Nearly 9.6 million women in the U.S. used birth control pills in 2014, according to the Guttmacher Institute, a research organization that supports sexual and reproductive rights. People are increasingly getting those pills delivered by mail: Mail-order pharmacies represented 15.2 percent of the total outpatient drug market in 2013. Now, in the age of telemedicine apps that prescribe and ship contraception around the country—including for people without insurance—even more women likely receive birth control pills through mail today.

The figure could rise further as birth control gets harder to access for low-income people. Due to the Trump Administration’s recent changes to the Title X family planning program, some people who don't have insurance and used to pay nothing for birth control at clinics are now facing costs of $120 a month, while others who paid $30 are stuck with $200 bills. Telemedicine apps like Nurx, Pill Club, and Hers ship you birth control for less than these amounts without insurance. As birth control gets more expensive at clinics that used to rely on federal funding, these apps could gain even more customers.

Postal workers are most at risk

About 70 percent of U.S. Postal Service (USPS) vehicles did not have air conditioning as of 2017, according to a report by the Center for Public Integrity.

The consequences of delivery vehicles lacking AC can be tragic. In July 2018, California mail carrier Peggy Frank was found dead in her non-air-conditioned mail truck on a 117-degree day; the coroner said she died from overheating. Congressman Tony Cárdenas introduced a bill in Frank's name that would require all delivery vehicles leased or owned by the Postal Service to have AC.

The mail carrier who documented the sun-cooked steak sent photos and other information to Arizona state representative Shawnna Bolick. Bolick issued a letter to the president of the postal worker’s union, the Postmaster General, and others on July 31 condemning the inhumane working conditions for Postal Service employees—several in the area had to be taken to the emergency room for heat stroke and heat exhaustion in the weeks prior. The photos and the letter went viral.

Yet despite the publicity and efforts to make a change, little has shifted. None of the three postal workers VICE interviewed reported having AC in present or past vehicles; none of them wanted to use their names for fear of retribution. Two Postal Service workers in Arizona reported regularly observing temperatures above 125 degrees Fahrenheit in their vehicles. A postal worker in New Mexico provided an image of a thermometer reading 119.5 degrees in his truck from August 7.

How does heat affect birth control pills and other medications?

“The Postal Service does not have a separate method to process/deliver prescription medications, including prescription medications that require temperature-controlled environments,” said Kim Frum, senior public relations representative for the Postal Service. "The sender takes the action for items that require cold chain or temperature control through packaging and temperature control measures inside their packages." Two of the Postal Service workers interviewed said even the vehicles used for interstate shipping lacked air conditioning, at least in cargo areas.

Things can get even worse inside mailboxes. A 1996 FDA study found that, on a 101-degree day, mailboxes can heat to 136 degrees. And though exposure to extreme heat is more common in southern states, the increasing frequency of heat waves poses challenges everywhere. (Heat isn’t the only problem for medications either—ultraviolet radiation, extreme cold, and varying humidity can also impact mail-order prescriptions.)

Understanding how temperature swings impact birth control pills is important for determining the potential risk in getting medicine shipped. Despite this, there are only a small number of studies exploring the issue.

“Oral contraceptives are a great example where there's not really any data looking specifically at keeping these medications at a high temperature for extended periods of time,” said Steve Dudley, a clinical toxicologist and director of the Arizona Poison and Drug Information Center at the University of Arizona College of Pharmacy. “Those [medications] are mostly hormones, like estrogen and progestin, and we do know, like all proteins, they are sensitive to heat for a prolonged period of time.” However, Dudley did explain that some medications, though not birth control pills specifically, have been proven to maintain potency even after prolonged exposure to extreme heat.

If your medications appear melted or discolored, he recommended not taking them and contacting your provider or the local poison center. But he warned that medicines could be degraded without any apparent physical change.

“If it's something that was left in the truck for a couple of hours, is it possible for there to be some loss of potency? Sure,” Dudley said. “Is it enough to make a clinically significant difference, assuming it’s just that couple of hours? Probably not, but, again, the issue becomes if it's been in transit for a week or so, or if it's being stored at home in a hot environment, then absolutely that can cause a loss of potency and decrease efficacy. The results can be pretty dramatic, especially when you're talking about somebody who is trying to prevent conception.”

Illustration by Hunter French

With perfect use—that is, taking every single pill on time—birth control pills are 99 percent effective at preventing pregnancy, but with typical use, that figure drops to 91 percent. Some of that 8 percent gap in effectiveness could conceivably be due to heat-related damage to the pills. But we can't know without the proper research, nor will we know if birth control is failing more often because of the increase in reliance on the mail.

"Whether it's oral contraceptives or any other type of medications, that is a growing concern that's out there that's present through the increased use of mail-order," said Stephen Eckel, an associate dean at the University of North Carolina Chapel Hill Eshelman School of Pharmacy. He suggested mail-order pharmacies should draw on the traditional pharmaceutical supply chain’s experience in controlling and monitoring temperature.

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It's not just the the Postal Service that lacks AC

The iconic brown delivery vehicles of UPS are also without air conditioning. FedEx spokesman Jonathan Lyons declined to comment on whether its fleet has air conditioning in cargo areas. Daniel McGrath, DHL’s head of corporate communications & responsibility team in the Americas, told VICE that 95 percent of DHL delivery vehicles have AC, however, he added that in some cases air conditioning is only available in the main cabin and not where the mail is held. He did not provide the number of such vehicles with air conditioning in cargo areas.

Other parts of the shipping process could also potentially expose medications to temperature excursions. Matthew O’Connor, senior manager of public relations at UPS, said that cargo areas in most of UPS Inc.’s approximately 20,000 tractor-trailers are not air conditioned, though the ones on its airplanes are. FedEx, which handles Postal Service air transportation, did not confirm whether its airplanes are climate controlled or not.

A variety of climate-controlled transport and packaging options are available through DHL, UPS Inc., and FedEx, though senders, not customers, select the shipping method.

Two companies and one nonprofit that ship birth control pills—Nurx, Hers, and Planned Parenthood—do not use the climate-controlled options, which are more costly. This appears to be standard for most other companies providing mail-order birth control pills. Nurx ships in plastic mailing bags while Planned Parenthood Direct and Hers ship in bubble mailers. Elizabeth Clark, Planned Parenthood’s director of health media, said on a press call that birth control pills can generally withstand up to 104 degrees, though she did not provide a source for this statistic and VICE could not confirm it with pharmaceutical experts. “If any patients have a situation where they have concerns about their shipment and about temperatures or extremely hot weather, then we encourage them to reach out to the Planned Parenthood Direct support via the app and have that conversation” about replacement pills, she added.

Dudley speculated that the 104-degree figure may have come from the U.S. Pharmacopeia National Formulary (USP-NF), which establishes the official standards for drug products recognized by the U.S. Food and Drug Administration. The USP-NF states that brief exposure to temperatures up to 40 degrees Celsius (104 Fahrenheit) may be tolerated, as long as a measure known as mean kinetic temperature—or the total thermal stress that a product experiences during storage and shipping—does not exceed 25 Celsius (77 Fahrenheit). But it doesn't say how brief is "brief," Dudley said. "The other issue is that if no one is monitoring the temperature at all times, so there is no way to know what the mean kinetic temperature is and if it's exceeded the threshold."

Eckel was concerned about the potential risks from birth control pills exposed to such temperatures. “Birth control pills have quite a few different ingredients associated with them,” Eckel said. “We need to better understand the impact of temperature fluctuations and shipping on medication.”

Healthcare companies are increasingly requiring that we get our meds by mail, AC or not

Eckel also mentioned the recent experience of Loretta Boesing, a Missouri woman who claims her son’s anti-rejection medicine following a liver transplant was compromised by heat while in transit. Boesing was not allowed to pick her medication up at her local pharmacy because of the policy of her Pharmacy Benefit Manager (PBM). “PBMs were originally put in to help manage costs within healthcare settings,” Eckel explained, with one of the strategies being to mail up to three months' worth of medication for a similar co-pay as you'd pay in person. But, he said, as the healthcare industry consolidates and drug stores partner with or own both a PBM and/or an insurance company, that vertical alignment to reduce costs also reduces patients’ choice. "If one wants to go and utilize their pharmacist, they may or may not be able to do that based upon the way their insurance requests out for medications," he said.

Eckel acknowledged how mail-order prescriptions expand healthcare access but lamented what could be missed. “To me, one of the biggest concerns with mail-order is a loss of interaction with a pharmacist,” he said. “You can walk into your pharmacy at any point in time and get your questions answered. Regardless of whether there's heat concerns or heat effects there, you lose the ability to have that individual that's caring for you.”