Making, Measuring, and Using Water-Accommodated Fractions of Petroleum for Toxicity Testing

Abstract

Oil spill response can be highly affected by the perceived costs and benefits of a particular countermeasure. Responders' perceptions of these can be influenced by the means in which scientific data are collected and presented. To date, a large amount of information has been generated on the aquatic toxicity of oil, dispersants, and dispersed oil. Unfortunately, many of these data are not comparable because of differing toxicological and analytical methodologies, as well as frequent lack of analytical verification of exposures. Recently, a group of federal, state, academic, and industry representatives from North America and Europe have been working toward standardizing both biological and analytical methods used to produce acute toxicity estimates for complex mixtures such as oil, dispersants, and dispersed oil. This standardization provides guidelines for future investigations to be conducted in a sufficiently rigorous manner to allow both inter- and intra-laboratory dataset comparisons, thus providing a more coherent and robust database from which to derive response guidance. By encouraging the use of these standardizations, it is hoped that decision-makers can be provided with a clearer understanding of the acute toxicological results of oil dispersal, and that such information can be more properly integrated into the response planning and decision-making processes.

Effects of Exposure of Pink Shrimp, Farfantepenaeus duorarum, Larvae to Macondo Canyon 252 Crude Oil and the Corexit Dispersant

“…That these results differ somewhat may be explained by variation in exposure methods used (constant, spiked, static renewal), however, each study reported a similar toxicity for WAFs and CEWAFs based on comparison of TPHs. Similar results have been reported for Americamysis (Holmesimysis) costata (1-35 mg L´1 WAF, 8-33 mg L´1 CEWAF, 96 h) and L. setiferus juveniles (6.5 mg L´1 WAFs, 5-7.5 mg L´1 CEWAFs, 96 h) [13,25,44]. In contrast, we report a 96 h TPH toxicity with larval F. duorarum (0.029-0.037 mg L´1 WAFs, 0.27-1.38 mg L´1 CEWAFs), indicating that WAFs were more toxic.…”

Phototoxic potential of undispersed and dispersed fresh and weathered Macondo crude oils to Gulf of Mexico Marine Organisms

“…The WAF preparation is based on previous methods described in Singer et al and Barron and Ka'aihue . Low‐energy WAFs were prepared in 10‐L clear glass aspirator bottles with a bottom dispensing port.…”

Effects‐driven chemical fractionation of heavy fuel oil to isolate compounds toxic to trout embryos

“…Chronic toxicity was measured by exposing trout embryos for 25 d, from hatch to swim-up, to chemically dispersed oil or oil fractions [16,25], with death as the only endpoint considered. Fluorescence of water samples was used to determine measured hydrocarbon concentrations, which were the basis for calculating median lethal concentrations.…”