Mysid shrimp bioassay

Mud Toxicity Test. Presently, the only toxicity test for drilling fluids having an EPA approval is the Mysid shrimp bioassay. The test was developed in the mid-1970s as a joint effort of the EPA and the oil industry. 

The mysid shrimp, Mysidopsis bahia, is the test organism for the liquid and suspended particulate phases. This species has been shown to be exceptionally sensitive to toxic substances and is considered to be a representative marine organism for bioassay testing by EPA. An LCj, is determined the suspended particulate phase (SPP) bioassay tests. 

TOXICITY LC50 (bluegill Lepomis macrochirus) 1700 p.g/L/96-hr in a static bioassay LC50 (mysid shrimp Mysidopsis bahia) 970pg/L/96-hr in a static bioassay LC50 (sheepshead minnow Cyprinodon variegatus) 2230 pg/L/96-hr in a static bioassay... 

TOXICITY larvae of eastern oyster Crassostrea virginica) LC50, 48 hr 1 mg/L, initial cone., static test (after 48 hr, only about 30% of original cone, was still present) bluegill sunfish Lepomis macrochims), LC50 29,300 mg/L/96-hr static bioassay mysid shrimp (Mysidopsis bahia), LC50 24,400 mg/L/96-hr static bioassay sheepshead minnow (Cyprinodon variegatus), LCso. 17,900 mg/L/96-hr static bioassay moderate acute and chronic toxicity to aquatic life... 

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