Fate of polycyclic aromatic hydrocarbons in controlled ecosystem enclosures

Abstract

Prudhoe crude oil enriched with a number of polycyclic aromatic hydrocarbons was added as a dispersion to a controlled ecosystem enclosure suspended in Saanich Inlet, Canada. Concentrations of various aromatics were determined in water, zooplankton, oysters, and bottom sediments. Initial water concentrations of the lower weight aromatics, naphthalenes and anthracene, were 10-20 gg/L, whereas the initial concentrations of benzo(a)pyrene, benz(a)anthracene, and fluoranthene ranged from 1 to 6 ag/L. These concentrations decreased at an exponential rate due to evaporation, photochemical oxidation, microbial degradation, and sedimentation.Only naphthalenes were significantly degraded by microbes with removal by this process of up to 5% per day from the water. Sedimentation and photochemical oxidation were responsible for the decrease in concentrations of the higher weight aromatics.This paper summarizes an experimental study of the fate of a number of polycyclic aromatic hydrocarbons of increasing molecular weight in a controlled ecosystem enclosure. The hydrocarbons included naphthalene, methylnaphthalenes, dimethylnaphthalenes, anthracene, fluoranthene, benz(a)anthracene, and benzo(a)pyrene. Prudhoe crude oil was enriched with these aromatics and added as a dispersion to a quarter-scale enclosure (ca. 2 m diameter and 15 m deep-60 000 L). After oil addition, water, sediment, zooplankton, For radioautographic studies (G, 3H) benzo(a)pyrene (25 Ci/mM-Amersham) was added to water samples. A two-step

Subacute toxicity of the water-soluble fractions of Kuwait crude oil and partially combusted crude oil on Menidia beryllina and Palaemonetes pugio

“…It was not surprising that chrysene and benzo(a)pyrene were below detection limits in tissue homogenates since these PAHs are not frequently detected in marine organisms exposed to petroleum contaminants. Naphthalene and naphthalene derivatives, however, have been detected with more frequency (Lee et al 1978;McDonald et al 1992;. It is possible that the parent PAHs present in our exposure water were taken up and rapidly metabolized.…”

PAH assessment in the main Brazilian offshore oil and gas production area using semi-permeable membrane devices (SPMD) and transplanted bivalves

“…Naphthalenes are volatiles and are more soluble than phenanthrenes and dibenzothiophenes. Furthermore, naphthalene degradation has been reported in waters from pristine and oil-contaminated ecosystems (Lee et al, 1978, Herbes and Schwall, 1978, Lee and Ryan, 1983, Massie et al, 1985. Naphthalene is relatively water soluble (31.2 mg L À 1 ) and has such a high vapor pressure (0.23 mmHg) that biodegradation and volatilization in open waters may be important processes that affects its fate in aquatic systems.…”

Porticoccus hydrocarbonoclasticus sp. nov., an Aromatic Hydrocarbon-Degrading Bacterium Identified in Laboratory Cultures of Marine Phytoplankton

“…In a study by Kowalewska (23), phytoplankton cells significantly contributed to the transport of PAHs from the upper layers of the Southern Baltic ecosystem to the sea floor by sedimentation. Although the hydrophobic nature of PAHs (log K ow ϭ 3 to 8) greatly limits their solubility in seawater, this property would favor their adsorption to marine particulate matter, including phytoplankton and detritus (11,27). Kowalewska (23) quantitatively demonstrated that different PAH compounds conferred different correlation coefficients for binding to phytoplankton cells.…”