Stable carbon isotope ratios as indices of petrochemical pollution of aquatic systems
Variations in the C13/C12 ratio of dissolved and particulate organic matter from several aquatic systems have been investigated. These measurements were made for natural and organic chemically polluted systems. C13 for natural systems ranges between -14 and -23 relative to the National Bureau of Standards isotope reference material No. 20. Petrochemical products and petrochemical effluents are much more depleted in C13, with a range from -25 to -49. C13 of the dissolved organic matter was measured for 15 samples from the Houston, Tex., Ship Channel. Model calculations based on these data suggest that the C13/C12 ratio of dissolved organic matter may serve as a quantitative index of petrochemical pollution.