Photo‐induced toxicity of Deepwater Horizon slick oil to blue crab (Callinectes sapidus) larvae

Abstract

The 2010 Deepwater Horizon oil spill resulted in the accidental release of approximately 700 million L of crude oil into the Gulf of Mexico. Photo-induced toxicity after co-exposure to ultraviolet (UV) radiation is 1 mechanism by which polycyclic aromatic hydrocarbons (PAHs) from oil spills may exert toxicity. Blue crab are an important commercial and ecological resource in the Gulf of Mexico, and their largely transparent larvae may make them sensitive to PAH photo-induced toxicity. The goal of the present study was to examine the sensitivity of early lifestage blue crab (Callinectes sapidus) zoea to slick oil collected during the Deepwater Horizon spill. Blue crab zoea were exposed to 1 of several dilutions of water accommodated fractions from 1 of 2 sources of oil and gradations of natural sunlight in a factorial design. Two 7-h solar exposures were carried out with a recovery period (dark) in between. Survival was found to be UV- and PAH-dependent. Toxicity was observed within the range of surface PAH concentrations reported in the Gulf of Mexico during the Deepwater Horizon spill. These findings indicate that early lifestage blue crab are sensitive to photo-induced toxicity from Deepwater Horizon slick oil.

Co‐exposure to sunlight enhances the toxicity of naturally weathered Deepwater Horizon oil to early lifestage red drum (Sciaenops ocellatus) and speckled seatrout (Cynoscion nebulosus)

“…All calculated tPAH 50 LC50s (0.18-5.78 mg /L) in the present study are within the lower range of PAH concentrations (0-84.8 mg/L) reported in the Deepwater Horizon spill area [29]. Deepwater Horizon spill oil, report total PAH median effective concentration (EC50) or LC50 values that are within an order of magnitude of those observed in the red drum and speckled seatrout tests [11,12,16,20]. (A) Mean percentage of mortality AE 1 standard error of larval speckled seatrout exposed to slick A high-energy water-accommodated fraction (HEWAF) and 1 of 3 ultraviolet (UV) treatments.…”

“…To account for differences in UV exposure, a phototoxic unit was calculated using methods similar to those of Oris and Giesy [5] and previously described in Alloy et al [12]. Tests not performed in parallel received different UV doses as a result.…”

“…They exert toxicity through several mechanisms, but photo-induced or photo-enhanced toxicity often occurs at concentrations below the threshold of other modes of toxicity [3][4][5]. Effects of PAH photo-induced toxicity include increased mortality [6][7][8][9][10][11], reduced fecundity [3], delayed hatching [12] increased photo-avoidance behaviors [5,13], and feeding inhibition [14]. Effects of PAH photo-induced toxicity include increased mortality [6][7][8][9][10][11], reduced fecundity [3], delayed hatching [12] increased photo-avoidance behaviors [5,13], and feeding inhibition [14].…”

Exposure to ultraviolet radiation late in development increases the toxicity of oil to mahi‐mahi (Coryphaena hippurus) embryos

“…Phototoxic doses were calculated using methods from Alloy et al and similar to Sellin Jeffries et al . To summarize, the concentrations of pPAH14 in each HEWAF sample were used in the calculations: anthracene; benzo[ a ]anthracene; benzo[ e ]pyrene; benzo[ g,h,i ]perylene; chrysene; fluoranthene; fluorene; C1 and C2 fluorenes; phenanthrene; C1‐, C2‐, and C3‐phenathrenes/anthracenes; and pyrene.…”

Deepwater Horizon Oil Spill as a Case Study for Interdisciplinary Cooperation within Developmental Biology, Environmental Sciences and Physiology

“…The RECOVER Consortium provides just such an opportunity in a cohesive unit. In previous work, we have shown that several native Gulf of Mexico species, including but not limited to early life stage crabs, mahi-mahi, and red drum are all sensitive to photo-induced PAH toxicity at concentrations well within the range observed during the DHOS (Figure 2) [61]. Funding provided by GoMRI will allow the multidisciplinary RECOVER team to continue to efficiently explore the mechanisms behind reduced survival of embryonic and larval stages of these species as well as potential mechanisms and outcomes of sublethal responses.…”