Sensitivity of fish embryos to weathered crude oil: Part I. Low‐level exposure during incubation causes malformations, genetic damage, and mortality in larval pacific herring (Clupea pallasi)

Abstract

Pacific herring eggs were exposed for 16 d to weathered Alaska North Slope crude oil. Exposure to an initial aqueous concentration of 0.7 parts per billion (ppb) polynuclear aromatic hydrocarbons (PAHs) caused malformations, genetic damage, mortality, and decreased size and inhibited swimming. Total aqueous PAH concentrations as low as 0.4 ppb caused sublethal responses such as yolk sac edema and immaturity consistent with premature hatching. Responses to less weathered oil, which had relatively lower proportions of high molecular weight PAH, generally paralleled those of more weathered oil, but lowest observed effective concentrations (LOECs) were higher (9.1 ppb), demonstrating the importance of composition. The LOEC for more weathered oil (0.4 ppb) was similar to that observed in pink salmon (1.0 ppb), a species with a very different development rate; by inference, other species may be similarly sensitive to weathered oil. Our methods simulated conditions observed in Prince William Sound (PWS) following the Exxon Valdez oil (EVO) spill. Biological effects were identical to those observed in embryolarval herring from PWS in 1989 and support the conclusion that EVO caused significant damage to herring in PWS. Previous demonstration by our laboratory that most malformed or precocious larvae die corroborates the decreased larval production measured after the spill.

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“…Field and laboratory investigations demonstrated that there was a common syndrome of crude oil-induced developmental toxicity in a range of teleost fish. This was described by pericardial edema, body axis curvature, yolk edema and jaw reductions (Heintz et al, 1999;Carls et al, 1999;Pollino and Holdway, 2002;Couillard, 2002). These results of the studies were in agreement with the current study.…”

Oil toxicity test methods must be improved

“…However, it models exposure not to fresh oil but to stranded, weathered oil. The composition and concentrations of test solutions change over days and weeks as the more water‐soluble components are depleted (Carls et al ; Martin et al ) and when droplets are periodically released from oil films (J. Adams, unpublished data).…”

Deepwater Horizon Oil Spill: A Review of the Planktonic Response

“…PAHs are known to be highly toxic to larval herring, topsmelt, minnow, and salmon (Petersen and Kristensen, 1998;Heintz et al, 1999;Couillard et al, 2005). Toxic effects include hemorrhages, spinal deformities, growth retardation, and death (Billiard et al, 1999;Carls et al, 1999 (Kujawinski et al, 2011). The use of subsurface dispersants combined with high pressure and turbulence at the wellhead likely contributed to the formation of the subsurface oil plumes that were unique to the DWH (Kujawinski et al, 2011).…”