In this Aug. 28, 2019, file photo, a man exhales while smoking an e-cigarette in Portland, Maine. Credit: Robert F. Bukaty | AP

Maine reported its first case of acute lung illness related to vaping or e-cigarette use Friday, a day after the eighth death from the same illness in the U.S. was reported in Missouri.

The disease linked to the use of e-cigarettes has led to 530 cases of lung illness nationally so far, according to the U.S. Centers for Disease Control and Prevention.

“This case highlights the risks and uncertainty about the short- and long-term effects of e-cigarette use,” said Maine CDC Director Nirav D. Shah. “People who do not vape should not start and people who do should seriously consider the health risks in using e-cigarette products.”

Symptoms of the illness include cough, shortness of breath, chest pain, nausea, vomiting, diarrhea, fatigue, fever and abdominal pain.

The cause is currently unknown and under investigation, but the U.S. CDC said most people who contracted the illness reported using vaping products that contained THC, the active ingredient in cannabis. Many of them used both THC and nicotine, and some reported using e-cigarettes containing only nicotine.

Seventy-two percent of the people who contracted the illness were male, and 67 percent were 18 to 34, according to the CDC.

Health experts do not know what the full list of chemicals contained in vaping products. And the national CDC’s investigation into the illness has not identified any common link among all the reported cases, such as a specific refill pod, cartridge or liquid.

Vaping products can have highly concentrated amounts of nicotine. A single pod can contain as much nicotine as a pack or two of cigarettes, said Dora Mills, chief health improvement officer for the MaineHealth hospital system and a former director of the Maine CDC.

Over the past year, Maine schools have reported a significant increase in the number of students using electronic smoking devices. E-cigarettes are now the most common tobacco product used by middle and high school students, with one in three Maine high school students having used them, according to the Maine CDC.

A new law that took effect Thursday will prohibit the use of e-cigarettes and vaping products on school premises.

According to the Washington Post, Walmart announced Friday that it will stop selling vaping products nationwide, including at Sam’s Club location.

“Finally people are realizing that these are dangerous products,” Mills said. “Your lungs are meant to breathe clean air, not chemicals. That’s the bottom line.”