Gschwend%20thesis.pdf

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Many workers have attributed aromatic hydrocarbons in air to automobile
exhaust, based on the composition similarity of air and exhaust samples, and
on the spatial and temporal covariations of high compound concentrations
and dense traffic (Grob and Grob, 1971, 1974; Altshuller et al., 1971;
Bertsch et al., 1974; Lonneman et al., 1978).
Very little work has been done concerning the C2- and C3-benzenes in
coastal seawater. Sauer et al. (l978) found levels of 0.3-24.4 ng/kg of
individual C2-benzenes in seawater from 8 coastal stations in the Gulf of
Mexico. They identified oil production and transport sources f0~ the aromatic
hydrocarbons.
Clark et al. (1974) have suggested that outboard engine exhaust may
be an important source of petroleum hydrocarbons to coastal seawater. They
indicated that about 10% of the fuel used by these engines may be put
directly into seawater.
In this chapter, efforts to ascertain the importance of atmospheric
delivery versus direct inputs of Cz- and C 3-alkylated benzenes are described.
Since my ability to assess air samples directly was limited by my analytical
capabilities, several independent approaches utilizing water sample analyses
were taken to provide insight to this problem. First, the long-term varia-
tions of these compounds found in the year-round study were investigated for
seasonal, tidal, and rain effects. Short-term temporal studies were conducted
to identify the timing and magnitude of effect of inputs associated with
intensified tourist and recreational activities on summer weekends (Chapter
3). Also, the isomer distributions of the C2- and C3-benzenes in some fuel
samples and the fractionation of these isomers in laboratory simulations of
transport into seawater were investigated. Four studies of the concentrations
of the aromatics in seawater samples from other nearby stations on the Sound