A Comparison of the chemical sensitivities between in vitro and in vivo propagated juvenile freshwater mussels: Implications for standard toxicity testing

Abstract

Unionid mussels are ecologically important and are globally imperiled. Toxicants contribute to mussel declines, and toxicity tests using juvenile mussels-a sensitive life stage-are valuable in determining thresholds used to set water quality criteria. In vitro culture methods provide an efficient way to propagate juveniles for toxicity testing, but their relative chemical sensitivity compared with in vivo propagated juveniles is unknown. Current testing guidelines caution against using in vitro cultured juveniles until this sensitivity is described. Our objective was to evaluate the relative sensitivity of juvenile mussels produced from both in vitro and in vivo propagation methods to selected chemicals. We conducted 96-h acute toxicity tests according to ASTM International guidelines with 3 mussel species and 6 toxicants: chloride, nickel, ammonia, and 3 copper-based compounds. Statistically significant differences between in vitro and in vivo juvenile 96-h median effect concentrations were observed in 8 of 17 tests, and in vitro juveniles were more sensitive in 6 of the 8 significant differences. At 96 h, 4 of the 8 statistically different tests for a given chemical were within a factor of 2, which is the intralaboratory variation demonstrated in a recent evaluation of mussel toxicity tests. We found that although differences in chemical sensitivity exist between in vitro and in vivo propagated juvenile mussels, they are within normal toxicity test variation. Therefore, in vitro propagated juvenile mussels may be appropriate for use in ASTM International-based toxicity testing. Environ Toxicol Chem 2018;37:3077-3085. © 2018 SETAC.

Conspicuous shell shape plasticity across lake-stream habitats in a freshwater mussel (Pyganodon grandis)

“…In addition to plasticity, multiple paternity and thus high genetic variation in a single brood (Figure 5a) suggests propagated and released individuals are not homogenizing genetic variation of natural populations (Inoue et al 2023). The prevalence of propagation programs in North America are now being leveraged for basic science, including the research conducted here but also in ecotoxicology (Buczek et al 2017, Popp et al 2018), thermal tolerance (Pandolfo et al 2010; Archambault et al 2013), and life-history (Lefevre and Curtis 1910; Coker et al 1921; Howard 1922; Sietman et al 2017; 2018), which may be equally valuable to mussel conservation as stocking.…”

Assessing the Toxicity of Sea Salt to Early Life Stages of Freshwater Mussels: Implications for Sea Level Rise in Coastal Rivers

“…Values were estimated with the Comprehensive Environmental Toxicity Information Software package (Ver 1.9.7.10) (n.d.). Confidence intervals (CIs) of 95% were calculated for each EC50, and EC50s with nonoverlapping CIs were considered statistically different (Archambault et al, 2013; Bringolf et al, 2007; Popp et al, 2018).…”

“…Seawater is composed of various salts but predominantly NaCl, which is a known toxicant to freshwater mussels and is widely used during unionid testing as a reference toxicant in chemical toxicity tests (ASTM International, 2013). It can become lethal to freshwater mussels, disrupt their ability to regulate bodily ions, and cause respiratory stress (Bringolf et al, 2022; Nogueira et al, 2015; Popp et al, 2018; Wang et al, 2017). Although seawater is rich in Na + and Cl − , it also contains other major ions such as Mg 2+ , Ca 2+ , K + , Sr 2+ , and SO 4 − , among others.…”