Abstract |
The paper gives results of measuring polycyclic aromatic hydrocarbons (PAHs) in ambient air particulates in Northern New England. Standard high-volume filter samples of ambient-air particulates were collected during several heating seasons in a semi-rural village, a rural area, and in residential and institutional neighborhoods in a small town in New Hampshire where wood is an important residential fuel. Extensive development work on extraction and cleanup schemes resulted in a reasonably convenient and reproducible procedure based on extraction of the filters with cyclohexane using ultrasonic agitation, chromatography on silica gel, and extraction of the PAH fraction into dimethylsulfoxide. Concentrations of 13 PAHs were determined by high performance liquid chromatography and by gas chromatography using both flame ionization and mass spectrometric detection. During 2 weeks of intensive sampling in late January 1982, the rural site showed the lowest PAH concentration, with Benz(a)pyrene (BaP) averaging about 1 microgram/cu m, compared to about 3 microgram/cu m in residential Hanover, NH. However, the variations in both the concentrations of individual PAHs among sites and the variations in the relative concentrations of the different PAHs were surprisingly small. Both the total suspended particulates and the PAH concentrations correspond well with the degree-day weather. |