Toxicity Tests Sample Clauses

Toxicity Tests. Implementation of a clearly defined QA/QC program is an integral part of conducting laboratory toxicity tests. A thorough and effective QA Program is the principal means of maintaining the accuracy and precision of field and laboratory analyses to assure scientific credibility. It ensures complete documentation and also standardizes and minimizes possible errors in computation and reporting of results. It is important that standard laboratory procedures be followed for all testing and that any unusual observations or deviations from established procedures be documented. The following general QA/QC guidelines (PSEP, 1995) apply. Negative Controls – All tests must be conducted using well-established negative (clean) controls. For every toxicity test, one series of test xxxxxxxx must only contain clean diluent water. The complete test series must be repeated if the mean control response does not meet the acceptability criteria for that test method. Positive Controls (Reference Toxicants) – all toxicity tests must contain positive (toxic) controls which are conducted with well-established standard reference toxicants. Reference toxicants are used to provide insight into mortalities or changes in sensitivity that may occur as a result of acclimation, disease, loading density or handling stress. For organisms obtained from outside sources (either purchased or field-collected), a reference toxicant test must be run for each new batch of organisms obtained. For organisms obtained from in-house laboratory cultures, reference toxicant tests can be performed on a monthly basis. Control charts should be constructed for each species and reference toxicant used and the cumulative mean value and upper and lower control limits (+ 2SD) should be plotted on each chart. If the results of a reference toxicant test fall outside the control chart limits, the test procedures and health/source of the test organism should be reviewed; subject to those findings, the test may have to be repeated. Test Organisms – Only healthy organisms of similar size and life history stage are used for toxicity tests. Taxonomic identifications should be confirmed by the qualified taxonomist. All test organisms used for a batch of tests must be from the same source. Records of collection, shipping and acclimation should be maintained for all species obtained from outside of the laboratory. Blind Testing – All treatment containers should be randomized during testing, and samples should be coded so th...