Determination of chemical composition and mutagenicity in particles from chainsaw exhaust. Experimental set-up, stability and results from two different fuels

A dilution tunnel for sampling of particles and gaseous emissions in chains aw exhaust was constructed and tested for reproducibility. In addition the equipment was used to measure chainsaw emissions when using two different f uels, aliphatic petrol with synthetic lubricating oil and regular lead-free petrol with mineral lubricating oil. The content of polycyclic aromatic hy drocarbons (PAH) and the mutagenicity of sampled particles were measured as well as the concentration of carbon monoxide (CO), nitrogen oxides (NOx) a nd aldehydes in the exhaust. particles were sampled isokinetically and coll ected on a filter followed by two polyurethane foam plugs (PUF) in series f or sampling of the semivolatile components. PAH were analysed by a coupled liquid chromatography - gas chromatography (LC-GC) system and mutagenicity testing was carried out by using Ames Salmonella assay. The measured physic al parameters as well as the particulate, semivolatile and gaseous emission s showed that reproducible measurements of exhaust emissions could be achie ved using this experimental set-up. In terms of mutagenicity when testing f or reproducibility, a small but significant effect was observed for the Sal monella strains TA98 and TA100 in the absence of a metabolizing system, bot h for the particulate phase and the semivolatile components. A significant difference was seen between the two different fuels tested, the conventiona l petrol with mineral oil having 5-10 times higher concentrations of differ ent PAH compounds and a much higher mutagenic effect for all strains. This difference was seen both for the particulate phase and the semivolatile com ponents.