ANALYTICAL METHODS FOR POLYNUCLEAR AROMATIC HYDROCARBONS IN CRUDE OILS, HEATING OILS, AND MARINE TISSUES*

Abstract

ABSTRACT This paper primarily covers the first phase of a project to demonstrate analytical methods in their ability to measure individual polynuclear aromatic hydrocarbons in typical petroleum oils and marine animal tissues. The study of petroleum oils is complete as described herein. Work on marine tissues is in its initial stage as an analytical method is shown to be capable of measuring benz(a)-anthracene and benzo(a)pyrene when added to clams at the 5 parts per billion (ppb) level. Evaluation of results indicate a detectability of 1 ppb. Eleven to sixteen individual hydrocarbons were measured in samples of a South Louisiana crude, Kuwait crude, a No. 2 heating oil, and a Bunker C fuel. These compounds included the principal 3-to 5-ring aromatics found in petroleum and one 6-ring (benzo(ghi)-perylene). The tricyclics (phenanthrene, methylphenanthrenes) were generally present in the highest concentration and covered the range 26–7677 ppm by weight. Four- and five-ring aromatics occurred in the range <0.5–240 ppm. Concentrations of the most widely studied polynuclear aromatic hydrocarbons, benzo(a)pyrene and benz(a)anthracene, were similar to one another being present at 0.6 to 2.8 ppm in the crude oils and heating oil, whereas in Bunker C their concentrations were 44 and 90 ppm, respectively Measurements of benzo(a)pyrene by previous investigators are tabulated and compared with those of this paper. Data are also presented to show that the alkyl-substituted forms of these compounds are present at much higher concentrations than the parent compound itself.