USGS Grant for Developing Freshwater Mussel Reproductive Toxicity Assessment Methods

Research Objectives:

The objectives of this funding opportunity are to provide science to assess the sensitivity of mussels to long-term chemical exposure.  Currently, the ASTM standard methods recommend a test duration of 28 days for conducting chronic toxicity test with juvenile mussels, and the test endpoints are survival, growth (individual length and dry weight), and biomass (total dry weight of surviving organisms per replicate) – unlike test methods for fishes, there are no accepted test methods for mussel reproduction at present. There is considerable uncertainty that the survival and growth responses from chronic 28-day exposures can be used to adequately assess reproductive impacts.

The main goal of this project is to develop methods to determine reproductive effects on freshwater mussels, and using the newly developed methods to evaluate the toxicity of
a CERCLA hazardous chemicals.  Specific studies include:
 

Develop methods using a short-term brooding mussel to evaluate the effects of a model chemical in a partial life cycle test.  
Refine and validate a partial life cycle test method using a chemical of interest to mussel resource managers.  

Methods will be used by federal, regional, and state risk assessors to screen, regulate, and
mitigate chemicals that occur or have the potential to occur in listed mussel habitat and used to update ASTM International standard methods for toxicity testing with mussels.