The use of e-cigarettes was found to have a negative impact on the heart and lungs as the American Heart Association (AHA) calls for further research into the issue.

“E-cigarettes deliver numerous substances into the body that are potentially harmful, including chemicals and other compounds that are likely not known to or understood by the user,” volunteer chair of the AHA scientific statement writing committee Jason Rose said in a new scientific statement released Monday.

“There is research indicating that nicotine-containing e-cigarettes are associated with acute changes in several hemodynamic measures, including increases in blood pressure and heart rate,” he added.

The statement pointed to research that found there was a “significant association” between e-cigarette use and the development of incident respiratory disease over two years, including chronic obstructive pulmonary disease/COPD, chronic bronchitis, emphysema or asthma. The statement also said that the ingredients of e-cigarettes — even in those without nicotine — can pose health risks.

“There has also been research indicating that even when nicotine is not present, ingredients in e-cigarettes, particularly flavoring agents, independently carry risks associated with heart and lung diseases in animals,” Rose said. “Negative effects of e-cigarettes have been shown through in vitro studies and in studies of individuals exposed to chemicals in commercially available products.”

The statement noted that vitamin E acetate is the ingredient that is likely causing E-cigarette, or Vaping, product use Associated Lung Injury (EVALI) hospitalizations. The statement added that more research is needed to determine the health impacts it can have on heart attacks and strokes.

The statement also pointed out that e-cigarettes are the most commonly used tobacco product among high school and missle age students. Rose said that this is “equally concerning” because there is also a correlation between e-cigarette use and substance use disorders.

“Because e-cigarettes and other vaping systems have only been in the U.S. for about 15 years, we do not yet have enough information on their long-term health effects, so we must rely on shorter term studies, molecular experiments and research in animals to try to assess the true risk of using e-cigarettes,” Rose added.

“It is necessary for us to expand this type of research since the adoption of e-cigarettes has grown exponentially, especially in young people, many of whom may have never used combustible cigarettes,” he said.