By Christina B. Farnsworth. A peer-reviewed report approved in October 2002 by the 6,000-member American College of Occupational and Environmental Medicine offers some hope that mold is not as severe a health risk as many fear. "Adverse Human Health Effects Associated with Molds in the Indoor Environment" reports outdoor molds are more abundant and figure more prominently in making people ill than indoor molds. The study says that only 10 percent of the population is sensitive to mold and that only 5 percent might be expected to become ill.