Hookah-tobacco users might want to rethink how they heat up their water pipes, based on research by researchers at the University of Cincinnati.
The gooey, flavorful tobacco in hookah pipes is normally burned with specially made charcoal briquettes, which can contain heavy metals or other toxins. But a study by UC graduate student Ryan Saadawi found that a popular alternative - electric heating disks sold in most tobacco shops - might be far more harmful to your health.
‘Unlike e-cigarettes, which heat liquid into a vapor, hookah pipes burn real tobacco mixed with glycerine and flavorings.’
The study heated the same hookah tobacco with two types of commercially available charcoal and an electric heat source sometimes called e-charcoal.
UC researchers found that:
Lower-toxin charcoal killed 10 percent of lung cells after 24 hours.
Higher-toxin charcoal killed 25 percent of lung cells.
E-charcoal killed a whopping 80 percent of lung cells.
"We're never supposed to be surprised in science. I was shocked and excited to open a whole new field of research just based on temperature," said Saadawi, lead author of a paper he presented April 2 at the American Chemical Society conference in San Francisco, California.
Saadawi, 30, of Cincinnati, has been studying this popular form of tobacco use for years.
The practice of smoking tobacco with a water pipe called a hookah began hundreds of years ago in southeast Asia and spread across the Middle East. Today, hookah tobacco is smoked around the world. Many cities in the United States have hookah cafes where people get together to smoke socially.
Unlike e-cigarettes, which heat liquid into a vapor, hookah pipes burn real tobacco mixed with glycerine and flavorings.
The researchers designed an experiment to examine the toxicity of hookah smoke on human lung cells. In particular, Saadawi wanted to measure the toxic effects of the charcoal commonly used to burn tobacco in hookah pipes.
The UC research team includes doctoral students Amberlie Clutterbuck, Madison Nashu and assistant research professor Julio Landero Figueroa.
For the latest study, the UC researchers compared two types of commercially available charcoal using the same hookah tobacco. A chemical analysis revealed one charcoal contained a higher concentration of heavy metals such as cadmium, arsenic and lead than the other.
They subjected lung cells to an extract of the resulting hookah smoke at different dilutions. The sample taken from the lower-toxin charcoal killed about 10 percent of the lung cells after 48 hours. The second sample, which used charcoal laced with heavy metals, killed about 25 percent of the lung cells.
Then Saadawi and his research team at the McMicken College of Arts & Sciences compared these results to hookah smoke from tobacco burned electronically by a ceramic disk (sometimes called e-coal). They figured the electronic heat source would provide a good control group to compare with the different charcoals. Instead, they found something surprising.
The smoke generated by the electronic heat source killed a whopping 80 percent of the lung cells.
"The results didn't make sense. My hypothesis was to find more dead lung cells in toxic charcoal," he said.