The easiest way for most smokers to avoid harmful smoke toxins may be simply to smoke stronger marijuana. This strategy is apt to be more effective than any smoke filtration device. By simply replacing the low, 2.3% potency NIDA marijuana used in this study with high-quality 12%-sinsemilla, smokers could presumably reduce their tar intake by a factor of five while still achieving the same effect.

Are Waterpipes Counterproductive?

The study results are obviously discomforting to waterpipe enthusiasts, many of whom prefer the cooler, milder smoke they produce, and have naturally assumed it is also more healthful. Unfortunately, however, the study indicates that waterpipes may actually be counterproductive in increasing consumption of carcinogenic tars.

Nonetheless, it is still premature to judge that waterpipes are actually unhealthful, since they may filter out other, non-solid smoke toxins occurring in the gas phase of the smoke, which was not analyzed in the study. Noxious gases known to occur in marijuana smoke include hydrogen cyanide, which incapacitates the lung's defensive cilia; volatile phenols, which contribute to the harshness of the taste; aldehydes, which promote cancer; and carbon monoxide, a known risk factor in heart disease. Previous studies indicate that water filtration may be quite effective in absorbing some of these [Nicholas Cozzi, Effects of Water Filtration on Marijuana Smoke: A Literature Review, MAPS Newsletter, Vol. IV #2, 1993]. If so, waterpipes might still turn out to have net health benefits.

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