As part of an investigation into the relationship of volatile organic compounds in ambient air and a nearby refinery, a risk assessment was performed as well as an analysis of the attribution of each source contributing to the emission of pollutants. The compounds under consideration being the alkanes, chlorinated hydrocarbons, aromatics, and aldehydes. Taking into account the sources (refinery and/or traffic) and the possible source-attributable pollutant combinations, locally dependent pollution profiles were observed. While aromatics and aldehydes were distributed relatively uniformly, the combination aromatics and alkanes at several localities pointed clearly to the refinery as the source of the pollution. An analysis of the indoor measurements at a school close to the refinery demonstrated the necessity of identifying the source of the pollutants in order to be able to bring about environmental conditions acceptable to human health.