NEW YORK, N.Y. January 12, 1998 -- Scientists have known for decades that the tars and other solid components of cigarette smoke are harmful to human health. But what about the gaseous components of the smoke?

New research shows that one category of these gas-phase chemicals, in particular a group called aldehydes, causes a large proportion of the damage, at least in blood plasma. Armed with this knowledge, a new filter could be designed to snag exactly these chemicals. While not encouraging anyone to smoke, the researchers believe they will be able to make smoking safer for those who have not quit.

The researchers pinpointed aldehydes -- a group of chemicals known for their rich fragrances as well as their high level of chemical reactivity -- as a significant source of damage to cells and molecules resulting from filtered cigarette smoke. The group included Dr. Abraham Reznick of the Technion-Israel Institute of Technology, Dr. Lester Packer of the University of California at Berkeley and Dr. Carroll Cross of the University of California, Davis Medical School. The results were published in several journals including the Biochemical Journal, American Journal of Clinical Nutrition,Redox Reports and the Journal of Laboratory and Clinical Medicine..

In their experiments, performed in the test tube, the researchers took filtered cigarette smoke and puffed it onto a prepared solution of plasma, the liquid component of blood. Their method allowed them to isolate the handful of chemicals present in cigarette smoke that are likely to penetrate the lining of the lungs and test their effects on plasma.

Then they used a vacuum system to expose the plasma to the equivalent of the smoke from one cigarette every three hours. They then observed the changes in plasma proteins and the damaging oxidation to plasma lipids (a kind of fats) that occurred.

Surprisingly, the researchers found that oxygen radicals -- a component of cigarette smoke which had previously been thought to be a chief culprit in long-term damage to the cells -- had relatively little effect. By contrast, says Reznick, aldehydes were "the real nasty guys" since they had multiple deleterious effects. The aldehydes, especially unsaturated aldehydes, caused a rapid modification of plasma proteins, changes that are thought to lead to long-term damage if the same chemical modifications occurred in cellular protein.

Interestingly, sulfur containing compounds such as glutathione (GSH) and dihydrolipoic acid (DHLA) were able to modify the harmful effects of the aldehydes. These compounds may be candidates for use as chemicals that bind to the filter and block the passage of these nasty aldehydes.

Another group of researchers from the University of California at Berkeley, headed by Dr. Rolf Melhorn, have begun working on a filter that would eliminate several noxious chemicals, including aldehydes, from cigarette smoke. They have applied for a patent on their work.

The Technion-Israel Institute of Technology is the country's premier scientific and technological center for applied research and education. The majority of Israel's engineers are Technion graduates, as are most of the founders and managers of its high-tech industries. The university's 11,000 students and 700 faculty study and work in the Technion's 19 faculties and 30 research centers and institutes in Haifa.The American Technion Society (ATS) is the university's support organization in the United States. Based in New York City, it is the leading American organization supporting higher education in Israel.

Note: If no author is given, the source is cited instead.

• Smoking
• Lung Cancer
• Staying Healthy

• Emphysema
• Smoke
• Blood test
• Bronchitis
• Radical (chemistry)
• Nicotine