Aquatic toxicology
[2] Typically using selected organisms with ecologically relevant sensitivity to toxicants and a well-established literature background.
[3] While basic research in toxicology began in multiple countries in the 1800s, it was not until around the 1930s[4] that the use of acute toxicity testing, especially on fish, was established.
Due to the wide use of the organochlorine pesticide DDT [l,l,l-trichloro-2,2-bis(p-chlorophenyl)ethane] and its linkage to causing fish death, the field of aquatic toxicology grew.
[5] Over the next two decades, the effects of chemicals and wastes on non-human species became more of a public issue and the era of the pickle-jar bioassays began as efforts increased to standardize toxicity testing techniques.
[1] Public awareness, as well as scientific and governmental concern, continued to grow throughout the 1970s and by the end of the decade research had expanded to include hazard evaluation and risk analysis.
[1] In the subsequent decades, aquatic toxicology has continued to expand and internationalize so that there is now a strong application of toxicity testing for environmental protection.
Common standard test species are the fathead minnow (Pimephales promelas), daphnids (Daphnia magna, D. pulex, D. pulicaria, Ceriodaphnia dubia), midge (Chironomus tentans, C. riparius), rainbow trout (Oncorhynchus mykiss), sheepshead minnow (Cyprinodon variegatu),[8] zebra fish (Danio rerio),[9] mysids (Mysidopsis), oyster (Crassotreas), scud (Hyalalla Azteca), grass shrimp (Palaemonetes pugio) and mussels (Mytilus galloprovincialis).
[10] As defined by ASTM International, these species are routinely selected on the basis of availability, commercial, recreational, and ecological importance, past successful use, and regulatory use.
Some of the more widely accepted agencies to publish methods are: the American Public Health Association, US Environmental Protection Agency (EPA), ASTM International, International Organization for Standardization, Environment and Climate Change Canada, and Organisation for Economic Co-operation and Development.
Bioaccumulation tests use bioconcentration factors (BCF) to predict concentrations of hydrophobic contaminants in organisms.
Temperature, water quality parameters and light will depend on regulator requirements and organism type.
[1] In the US, many wastewater dischargers (e.g., factories, power plants, refineries, mines, municipal sewage treatment plants) are required to conduct periodic whole effluent toxicity (WET) tests under the National Pollutant Discharge Elimination System (NPDES) permit program, pursuant to the Clean Water Act.
For facilities discharging to freshwater, effluent is used to perform static-acute multi-concentration toxicity tests with Ceriodaphnia dubia (water flea) and Pimephales promelas (fathead minnow), among other species.
For discharges to marine and estuarine waters, the test species used are sheepshead minnow (Cyprinodon variegatus), inland silverside (Menidia beryllina), Americamysis bahia, and purple sea urchin (Strongylocentrotus purpuratus).
For this reason, sediment toxicity can play a major role in the adverse biological effects seen in aquatic organisms, especially those inhabiting benthic habitats.
Collection, handling, and storage of sediment can have an effect on bioavailability and for this reason standard methods have been developed to suit this purpose.
[1] In the United States, aquatic toxicology plays an important role in the NPDES wastewater permit program.
While most wastewater dischargers typically conduct analytical chemistry testing for known pollutants, whole effluent toxicity tests have been standardized and are performed routinely as a tool for evaluating the potential harmful effects of other pollutants not specifically regulated in the discharge permits.
[25] These sediment quality guidelines are summarized in NOAA's Screening Quick Reference Tables (SQuiRT) for many different chemicals.
