Environ. Sci. Technol. 2000, 34, 2714-2720
Airborne Particle Emissions from 2and 4-Stroke Outboard Marine Engines: Polycyclic Aromatic Hydrocarbon and Bioassay Analyses N O R M A N Y . K A D O , * ,†,‡ ROBERT A. OKAMOTO,‡ JOHN KARIM,‡ AND PAUL A. KUZMICKY† Department of Environmental Toxicology, University of California, Davis, California 95616, and California Air Resources Board, Sacramento, California 95814 and El Monte, California 91731
Outboard and personal watercraft (marine) engines are reported to be significant sources of air pollutants accounting for approximately 141 tons of reactive hydrocarbons emitted per day in California alone, for example. The emissions from 2-stroke marine engines have traditionally been investigated for the regulated pollutants hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx). However, very few studies have been published on airborne particulate matter (PM) and PM-associated unregulated toxic air pollutants emitted during the normal operation of the engine in the water. In the current investigation, we report on the airborne PM emissions from two types of 2-stroke marine engines (carbureted and direct fuel-injected models) and a 4-stroke engine (carbureted) that were operated in water at a special emissions testing facility. The engines were from 1998 or 1999 model years and were rated at 90 hp (maximum). The sampled airborne PM was analyzed for polycyclic aromatic hydrocarbons (PAHs) using gas chromatography/ mass spectrometric (GC/MS) analyses and further tested for genotoxic (DNA-damaging) activity using a microsuspension Salmonella bioassay procedure. The particle emissions were
