Aquatic Toxicology - Aquatic Toxicity Tests

Aquatic Toxicity Tests

Aquatic toxicology tests (biassays): toxicity tests are used to provide qualitative and quantitative data on adverse (deleterious) effects on organisms from a toxicant. Toxicity tests can be used to assess the potential for damage to an aquatic environment and provide a database that can be used to assess the risk associated within a situation for a specific toxicant. Aquatic toxicology tests can be performed in the field or in the laboratory. Field experiments generally refer to multiple species exposure and laboratory experiments generally refer to single species exposure. A dose response relationship is most commonly used with a sigmoidal curve to quantify the toxic effects at a selected end-point or criteria for effect (i.e. death or other adverse effect to the organism). Concentration is on the x-axis and percent inhibition or response is on the y-axis.

The criteria for effects, or endpoints tested for, can include lethal and sublethal effects (see Toxicological effects).

There are different types of toxicity tests that can be performed on various test species. Different species differ in their susceptibility to chemicals, most likely due to differences in accessibility, metabolic rate, excretion rate, genetic factors, dieteary factors, age, sex, health and stress level of the organism. Common standard test species are the fathead minnow (Pimephales promelas), daphnids (Daphnia magna, D. pulex, D. pulicaria, Ceriodaphnia dubia), midge (Chironomus tentans, C. ruparius), rainbow trout (Oncorhynchus mykiss), sheepshead minnow (Cyprinodon variegatu), mysids (Mysidopsis), oyster (Crassotreas), scud (Hyalalla Azteca), grass shrimp (Palaemonetes pugio), mussels (Mytilus). As defined by ASTM, these species are routinely selected on the basis of availability, commercial, recreational, and ecological importance, past successful use, and regulatory use.

A variety of acceptable standardized test methods have been published. Some of the more widely accepted agencies to publish methods are: the American Public Health Association, U.S. Environmental Protection Agency, American Society for Testing and Materials, International Standardization Organization, Environment Canada, and Organization for Economic Cooperation and Development. Standardized tests offer the ability to compare results between laboratories.

There are many kinds of toxicity tests widely accepted in the scientific literature and regulatory agencies. The type of test used depends on many factors: Specific regulatory agency conducting the test, resources available, physical and chemical characteristics of the environment, type of toxicant, test species available, laboratory vs. field testing, end-point selection, and time and resources available to conduct the assays are some of the most common influencing factors on test design.

Read more about this topic:  Aquatic Toxicology

Other articles related to "toxicity, aquatic toxicity tests, aquatic":

Surugatoxin - Background & Discovery
... The toxicity shellfish from the Suruga Bay area varied with time – the toxicity was only present during July through September, when temperatures sometimes reached 25°C and it rapidly declined after 1978 ... Toxicity is a result of bioaccumulation ...
MET Matrix
... A MET (Materials, Energy, and Toxicity) Matrix is an analysis tool used to evaluate various environmental impacts of a product over its life cycle ... the product's materials use, energy use, and toxicity ... energy use during the production phase, or levels of toxicity that may be a concern during the disposal phase ...
Aquatic Toxicology - Aquatic Toxicity Tests - Sediment Tests
... For this reason, sediment toxicity can play a major role in the adverse biological effects seen in aquatic organisms, especially those inhabiting benthic habitats ... apply the Sediment Quality Triad (SQT) which involves simultaneously examining sediment chemistry, toxicity, and field alterations so that more complete information ...

Famous quotes containing the word tests:

    What is a novel? I say: an invented story. At the same time a story which, though invented has the power to ring true. True to what? True to life as the reader knows life to be or, it may be, feels life to be. And I mean the adult, the grown-up reader. Such a reader has outgrown fairy tales, and we do not want the fantastic and the impossible. So I say to you that a novel must stand up to the adult tests of reality.
    Elizabeth Bowen (1899–1973)