Hemocyte Health Status Based on Four Biomarkers to Assess Recovery Capacity in American Lobster (Homarus americanus) after Exposure to Marine Diesel and Diluted Bitumen

Abstract

The growing transportation of petroleum products pose a significant risk of marine diesel or diluted bitumen (dilbit) spills at sea. Despite the economic importance of the American lobster, there have been few studies assessing the impact study of such a spill on their population. In the lobster industry, lobster quality is monitored according to the Brix index of hemolymph. In our research, the effectiveness of three other biomarkers operative in the industry was assessed in hemolymph during contamination (over 96 h) by marine diesel and dilbit (Cold Lake Blend; CLB), as well as in the subsequent recovery period, according to two temperature cycles. At the end of the experiment, chemical and tainting assays were performed. Our results demonstrate that, among the four tested biomarkers, lysosomal stability and ethoxyresorufin O-deethylase (EROD) induction exhibit higher sensitivity. Increasing the temperature did not shorten the recovery period. Viability cellular impacts were greater in lobsters exposed to dilbit than that in those exposed to marine diesel. Marine diesel exposure appears to be more problematic for the lobster fishery, as the cooked lobster meat still presented a hydrocarbon odor even after 3 months of live holding. Finally, the high PAH concentrations measured in lobster eggs suggest potential adverse transgenerational effects of marine diesel exposure.

Hemocytes: A Useful Tool for Assessing the Toxicity of Microplastics, Heavy Metals, and Pesticides on Aquatic Invertebrates

“…These substances reach aquatic ecosystems through various routes, directly through the discharge of chemical compounds into water or more indirectly through residues that have accumulated into the soil, and as a consequence of a flood, rains, or land runoff, they reach water sources. Organisms affected by these xenobiotics exhibit increased DNA damage, increased reactive oxygen species’ production, and disturbances in the hemolymph composition and the number of existing hemocytes [ 24 , 25 ].…”

“…One interesting study investigating the effects of organic mercury on the hemolymph of M. galloprovincialis reported that a concentration of 10 −5 M could induce morphological changes by changing the hemocyte’s shape and number and also reducing its ability to conduct phagocytosis [ 25 ]. In an older study about ionic regulation in the crayfish Orconectes propinquus upon mercury exposure for a 14-day [ 27 ] period, the author observed a significant decrease in Na + and Ca + , with the difference that the Ca + concentration increased after the depuration period [ 27 ].…”