On January 5, 2000, the National Institute for Occupational Safety and Health (NIOSH) received a request for a health hazard evaluation (HHE) from the United States Forest Service (USFS), Region 6, Office of Natural Resources. The request listed nausea, rashes, headaches, and dizziness as symptoms reported by Foresters who use NIOSH industrial hygienists conducted an exposure assessment for airborne metals, hydrocarbons (including methyl ethyl ketone (MEK) and toluene), and propylene glycol during tree-marking activities in the Deschutes temperature (over 80degF), low relative humidity (<30%) and work-crew sizes of 8-9 per day. Personal exposures to hydrocarbons, metals, and propylene glycol were all very low. MEK and toluene were undetected in personal breathing zone samples. None of the symptoms reported in the HHE request (nausea, dizziness, headaches) were reported by the work crew observed during this HHE, nor did they report experiencing such symptoms in the past while working. It is concluded that using the type of tree-marking paint evaluated in this HHE under these conditions does not present a health hazard to the work crews.