Toxicology and Potential Health Risk of Chemicals that May Be Encountered by Workers Using Forest Vegetation Management Options PART I: RISK TO WORKERS ASSOCIATED WITH EXPOSURE TO EMISSIONS FROM POWER SAWS

.............................................................................................................................. ii Acknowledgements ............................................................................................................. iii Foreword............................................................................................................................. iv Introduction ......................................................................................................................... 1 Emissions from Two-stroke Engines and the Nature of Their Health Effects ..................... 1 Exposure to Exhaust from Power Saws.............................................................................. 4 Estimation of Non-cancer or Systemic Risks ...................................................................... 6 Carbon monoxide (CO) ................................................................................................. 6 Aldehydes, particularly formaldehyde and acrolein....................................................... 7 Estimation of Cancer Risks ................................................................................................. 7 Benzene ........................................................................................................................ 9 1,3-butadiene ................................................................................................................ 10 Benzo(a)pyrene (BaP) and other PAH.......................................................................... 11 Conclusions ........................................................................................................................ 11 Recommendations .............................................................................................................. 12 References.......................................................................................................................... 13 Glossary .............................................................................................................................. 15 Titles in this Series.............................................................................................................. 18