Levoglucosan in PM2.5 at the Fresno supersite.

Ambient air monitoring for PM2.5 has been conducted on a daily basis at the Fresno, CA, supersite since 1999. It has been found that PM2.5 concentrations routinely exceed the National Ambient Air Quality Standards during the winter months. In an effort to determine the effect of biomass burning on PM2.5 concentrations, samples during 2000 were analyzed for levoglucosan, palmitic acid, and stearic acid. The results of this study are presented.

Oxalic acid in PM2.5 particulate matter in California.

Ambient air monitoring for organic acids in PM2.5 was conducted at several locations in California. During the study, it was found that oxalic acid (ethanedioc acid) was the most abundant organic acid found in the PM2.5 fraction. Samples from Azuza (in southern California), San Jose (in the San Francisco Bay area), and Fresno (in central California), a PM2.5 Super Site, were collected in 1999 and analyzed. The results for oxalic acid concentrations during this monitoring effort are presented.

The Application of the Karl Fischer Oven for the Determination of Water in Consumer Products.

The direct Karl Fischer (KF) titration method has known interferences for measuring water content. In addition, in analyzing some paints, KF can fail to produce an accurate analysis. The California Air Resources Board (GARB) staff has developed a KF procedure that can be used to determine the water content of consumer products. The procedure uses an oven accessory to the titration system, and is based on a distillation method developed by the California Polytechnical University at San Luis Obispo (Cal Poly). Samples are diluted in l-methoxy-2-propanol (MPA), and an aliquot is injected into an enclosed oven system, where the MPA/water azeotrope is swept directly into the KF titration vessel. The technique is accurate and precise and, thus far, proves to be a fast and reliable method for analysis.

Determination of Exempt and Prohibited Compounds in Consumer Products by Headspace Gas Chromatography Mass Spectrometry.

Title 17, California Code of Regulations, Division 3, Chapter 1, Subchapter 8.5, Articles 1 and 2, Sections 94500-94517 specify limits for volatile organic compounds (VOCs) in a wide variety of consumer products. However, under these regulations, specific compounds that have been shown to contribute little to the formation of ozone in the lower atmosphere are exempt from the definition of VOC. A headspace sampling and analysis method has been developed for the analyses of these compounds in consumer products. This method has been used successfully for analyzing aerosol and non-aerosol products.