Updated: 07/22/2013 - LAS VEGAS (AP) - University of Nevada, Las Vegas researchers have found that several hot sauce brands sold in the U.S. contain dangerous levels of lead. In what the university describes as a first-of-its-kind study, researchers examined 25 bottles of hot sauce imported from Mexico and South America and purchased from local ethnic markets, grocery stores, and a swap meet. They found that four of the bottles, or 16 percent, exceeded Food and Drug Administration standard for safe levels of lead. The results were released last week. Lead poisoning can affect every organ in the body and can cause learning disabilities and behavioral problems in young children. UNLV researcher Shawn Gerstenberger says his results point to the need for better screening of products imported from Mexico.