Petroleum hydrocarbons excretion

A susceptible population will exhibit a different or enhanced response to petroleum hydrocarbons than will most people exposed to the same level of petroleum hydrocarbons in the environment. Reasons may include genetic makeup, age, health and nutritional status, and exposure to other toxic substances (e.g., cigarette smoke). These parameters may result in reduced detoxification or excretion of petroleum hydrocarbons, or compromised function or organs affected by petroleum hydrocarbons. 

Excretion of the electrophilic intermediates as conjugated derivatives has been well identified in terrestial mammals as well as in marine species. All marine species investigated are able to conjugate the oxide intermediates to GSH-derivatives (Bend etaL, 1977). Generally, invertebrates show lower activity than vertebrates. In addition, wide variation in glutathione-S-transferase activity has been observed beween species and substrates used. Reasonable experimental evidence now exists for the enzyme-mediated biotransformation of petroleum hydrocarbons in several marine fish and invertebrate species. 

Overview. Because TPH is a broadly defined entity consisting of complex mixtures of hydrocarbons of varying chemical composition (due to differences in original petroleum products and differential, time-dependent, fate and transport of components within any particular TPH mixture), this section discusses available information for absorption, distribution, metabolism and excretion of components and petroleum products corresponding to the transport fractions of TPH. Limited... 

Comparative Toxicokinetics. Since there is sparse data on animal toxicokinetics, there is no information at all on comparative toxicokinetics. Studies of absorption, distribution, metabolism, or excretion would be appropriate in multiple animal species for interspecies comparisons. Comparisons between the pharmacokinetic properties of petroleum distillates of varying chain lengths and aromatics versus other hydrocarbon classes would also be useful. 

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