Developmental Toxicity of Copper Chloride, Methylene Chloride, and 6-Aminonicotinamide to Embryos of the Grass Shrimp Palaemonetes Pugio

Abstract

Abstract-Embryos of estuarine grass shrimpPalaemonetes pugio have demonstrated sensitivity to various solvents and petroleum products, indicating utility for evaluating estuarine contamination. Testing was performed to establish concentration-response curves for methylene chloride, copper chloride, and 6-aminonicotinamide, three known teratogenic chemicals. Two exposure periods were used, 4 d and 12 d, and both periods extended through hatching. The average 4-d LC50 values for methylene chloride, copper chloride, and 6-aminonicotinamide were 0.071% v/v, 1.82 mg/L, and 0.21 mg/ml, respectively. The average 12-d LC50 values for methylene chloride, copper chloride, and 6-aminonicotinamide were 0.031% v/v, 1.44 mg/L, and 0.057 mg/ml, respectively. Eye malformations were observed with embryos exposed to concentrations greater than 3 mg/L copper chloride or greater than 0.07% v/v methylene chloride. Very few abnormalities were observed in embryos exposed to 6-aminonicotinamide. Abnormal larval development was found with exposure to copper chloride at concentrations greater than 1 mg/L. The sensitivity and low variability found here further supports the development of these relatively simple methods using grass shrimp embryos. Establishment of sublethal developmental endpoints warrants further investigation because of their potential correspondence to mechanisms of toxic action.

Avoidance response by shrimps to a copper gradient: Does high population density prevent avoidance of contamination?

“…For instance, copper concentrations found to be lethally toxic to the shrimp Callianassa australiensis were between 1.0 and 2.0 mg L À1 for short (4 d) exposure (Rayburn and Fisher 1999) and 1 order of magnitude lower (0.1 mg L À1 ) for long (14 d) exposure (Ahsanullah et al 2018). Besides the environmental relevance of this response, spatial avoidance can be integrated in different endpoints used in other studies with crustaceans.…”

Reproductive and life stage-specific effects of aqueous copper on the grass shrimp, Palaemonetes pugio

“…Exposure to a much higher concentration of copper (3 mg Cu Total /L) was reported to reduce hatching success of P. pugio embryos in vitro (Rayburn and Fisher, 1999). Furthermore, copperinduced decreases in hatching success rates have been observed in other crustaceans such as crabs (Callinectes sapidus [Lee et al, 1996]) and mysid shrimp (Praunus flexuosus [Garnacho et al, 2001]).…”

“…Although this amount of time appears to be trivial relative to the length of the shrimp's life cycle, it results in a 12-18% increase in the duration of the larval stage, which may be the most vulnerable to predation due to its planktonic nature (Anderson, 1985). Additional examples of copper-induced delayed development in aquatic invertebrates include delayed embryonic development in P. pugio (Rayburn and Fisher, 1999), slower larval development in Metapenaeus ensis (shrimp; Wong et al, 1995) and Watersipora subtorquata (bryozoan; Ng and Keough, 2003), and delayed sexual maturation in Tigriopus japonicus (copepod; D' Agostino and Finney, 1974). Delays in metamorphosis may result in a greater impact of predators on population growth in areas where copper concentrations are elevated.…”

Effects of genotoxic compounds on DNA and development of early and late grass shrimp embryo stages

“…Embryos were removed from female grass shrimp by a cut at the stem attaching them to females following the procedures described by Rayburn and Fisher (1999). Embryos, approximately 400, from a single large female were used for each stage specific exposure with a particular test chemical.…”

“…At the end of embryonic development the stage 10 embryos hatch into a free swimming zoea stage which captures its own food. Grass shrimp, including embryos, larvae, juveniles and adult stages, have been used to determine the effects of environmental contaminants in both field studies and laboratory bioassays (Finley et al, 1998;Fisher and Foss, 1993;Fulton, Daugomah, Beardon, & Scott, 1998;Lee, Kim, Maruya, Steinert, & Oshima, 2000;Rayburn & Fisher, 1999;Rayburn, Glas, Foss, & Fisher, 1996). Glas, Courtney, Rayburn, and Fisher (1997) showed that late stage grass shrimp embryos were more permeable than early stages to certain toxicants.…”