Mesquite wood charcoal has been widely promoted for the unique taste it imparts to broiled food. We recently examined a 21-year-old mesquite broiler cook with evidence suggestive of respiratory allergy or irritation following exposure to mesquite broiler smoke in a Salt Lake City restaurant. We subsequently surveyed 13 mesquite and 17 gas-flame ("charcoal") broiler cooks to determine the prevalence of respiratory symptoms among workers exposed to broiler smoke. The survey demonstrated statistically significant (P less than or equal to .05) respiratory irritation in the mesquite broiler group compared with the gas-flame broiler group in one of four symptom categories. Two other symptom categories strongly suggested the presence of (P less than .10) respiratory irritation in the mesquite broiler group. Personal air sampling was conducted or two mesquite broiler cooks and two gas-flame broiler cooks and compared. Unidentified saturated and unsaturated aliphatic hydrocarbons (C8 through C12) with high molecular weights from 108 to 182 were present in air samples from the mesquite broiler cooks and not in the air samples from the gas-flame broiler cooks.