Toxicity tests species

It is therefore essential that before pivotal (repeat dose) preclinical studies are initiated, bioanalytical assay development must be completed. This has to cover potential test species, normal and diseased humans. The assays must be validated in the sampling matrix of the toxicity test species, and one should also develop suitable assays for antibodies to the test article. 

Whole effluent toxicity test species are generally not the same as the resident species that the results of WET testing are aimed at protecting, particularly where nontemperate environments (e.g., tropical and Arctic environments) are concerned, or for estuaries [177]. Also, not all resident species have the same sensitivities to individual or combined contaminants in effluents. Further, differences exist between sensitivities and tolerances of WET species. Such differences are not unexpected hence, it is desirable to use more than one toxicity test organism and endpoint to assess effluent toxicity. 

Toxicity test/ Species study Assessment endpoint Test phased Test duration Measurement endpoint Number of replicate/ Test method reference... 

Product (Approval Date) Mechanism of Action Indication Toxicity Test Species... 

Evolutionary events also occur within multispecies toxicity tests. Species or strains resistant to xenobiotics do arise. Simple microbial microcosms (chemostats) are often used to force the evolution of new metabolic pathways for pesticide and xenobiotic degradation. 

Toxicity Testing Species can be used as a model salmonid. 

Calculation of Safe Concentration. If the compound is noL a carcinogen, a no-observed-effect-level or NOEL will be determined from non-carcinogenic toxicity end points. The NOEL used in calculating permitted levels for residues is a level of sponsored compound in the diet of the toxicity test species for the most sensitive end point (lowest level) where there was no observed effect. This level is then used in a calculation of the safe concentration (S.C.) for the compound. The calculation also uses safety and food factors as well as a scale up factor for the body weight of man (60 kg) ... 

Acute toxicity test Species LD50/LC50 EPA toxicity cat ory... 

Table 1 Marine TIE toxicity testing species. Each of these species has been tolerance tested ...

The routine monitoring of every hazardous constituent of the effluent gases of operating incinerators is not now possible. EPA has established procedures to characterize incinerator performance in terms of the destruction of selected components of the anticipated waste stream. These compounds, labeled principal organic hazardous components (POHCs), are currently ranked on the basis of their difficulty of incineration and their concentration in the anticipated waste stream. The destraction efficiency is expressed in terms of elimination of the test species, with greater than 99.99 percent removal typically judged acceptable provided that toxic by-products are not generated in the process. 

Hooftman RN, de Wolf JM (2003a) Triohloromethylstannane (CAS 993-16-8) Static acute toxicity test with the crustacean species Daphnia magna. Zeist, TNO, May (Report No. V2492/02). 

Species The test species, whether animal or human, are identified in this column. Chapter 2, "Relevance to Public Health," covers the relevance of animal data to human toxicity and Section 3.4, "Toxicokinetics," contains any available information on comparative toxicokinetics. Although NOAELs and LOAELs are species specific, the levels are extrapolated to equivalent human doses to derive an MRL. 

As discussed earlier, selectivity is the consequence of the interplay between toxicokinetic and toxicodynamic factors. Some examples are given in Table 2.8, which will now be briefly discussed (data from Walker and Oesch 1983, and Walker 1994a,b). These and other examples will be described in more detail under specific pollutants later in the text. In the table, comparisons are made between the median lethal doses or concentrations for different species or strains. Comparisons are made of data obtained in lethal toxicity tests where the same route of administration was used for species or strains that are compared. The degree of selectivity is expressed... 

Compound Species Toxicity Test Value Units... 

Cytochrome P450-type monooxygenase systems, which have a generally low substrate specificity, are widely distributed in the species of fish used for toxicity testing (Funari et al. 1987). 

Acute toxicity In vitro Mammalian systems Aquatic vertebrates and invertebrates Plants IC/EC50 in appropriate test species Use of appropriate indicators of acute toxicity, for example, EPA guidance values, reference doses, and so on... 

McCrary JE, Heagler MG. 1997. The use of a simultaneous multiple species acute toxicity test to compare the relative sensitivities of aquatic organisms to mercury. J Environ Sci Health Part A Environ Sci Eng Toxic Hazardous Substance Control 32 73-81. 

In the case of surface water, the LOQ must not exceed a concentration which has an impact on nontarget organisms deemed to be unacceptable according to the requirements of Annex VI. At present, no harmonized limits for surface water exist. Therefore, provisions in Annex VI of Directive 91/414/EEC will be used to calculate guidance limits for analytical methods for surface water. In SANCO/825/00 the limits given in Table 6 are established [the relevant concentrations (the lowest will always be taken into consideration) depend on the species as indicated and can be taken from toxicity tests]. 

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