Toxicity measurements

Waste Disposal. Because of its low Boiling poiat and high, toxicity, measures must be taken to prevent the entrance of phosgene iato drains or sewers. If recycle of phosgene is not feasible, phosgene waste can be handled by one of the decomposition methods mentioned above, ie, caustic scmbbiag, moist activated carbon towers, or combustion. 

Toxicity is also frequentiy expressed as toxicity units (TU), which is 100 divided by the toxicity measured ... 

Hexachlorocyclotriphosphazene (cycHc trimer) is a respiratory irritant. Nausea has also been noted on exposure (10). Intravenous and intraperitoneal toxicity measurements were made on mice. The highest nonlethal dose (LDq) was measured as 20 mg/kg (11). Linear chloropolymer is also beUeved to be toxic (10). Upon organic substitution, the high molecular weight linear polymers have been shown to be inert. Rat implants of eight different polyphosphazene homopolymers indicated low levels of tissue toxicity (12). EZ has been found to be reasonably compatible with blood (13), and has lower hpid absorption than fiuorosihcone. 

For disodium undecyleneamido MEA-sulfosuccinate (DUMS) a test report [97] indicates that the subacute toxicity, measured as 30% of LD50 during 5 days, allowed all test animals to survive. 

Two main hazards associated with chemicals are toxicity and flammability. Toxicity measurements in model species and their interpretation are largely the province of life scientists. Chemical engineers can provide assistance in helping life scientists extrapolate their resrrlts in the assessment of chemical hazards. Chemical engineers have the theoretical tools to make important contributions to modehng the transport and transformation of chemical species in the body—from the entry of species into the body to their action at the rrltimate site where they exert their toxic effect. Chemical engineers are also more likely than life scientists to appreciate... 

NIOSH publishes IDLH concentrations to be used as acute toxicity measures for common industrial gases. An IDLH exposure condition is defined as a condition that poses a threat of... 

Workshop participants suggested that additional research should be conducted on the human health effects of POPs and that systems be established to promote the standardization of toxicity measurement of chemicals and to assess the qualifications of laboratories for toxicity appraisal. Furthermore, Good Laboratory Practice (GLP) laboratories need to be popularized in China to improve the quality and reliability of monitored data. 

Prepared a training data set of chronic toxicity measurements to statistically establish the relationship between chronic toxicity and PAH descriptors of interest. 

An issue of obvious importance in test species selection is the degree to which test results can be reliably applied to human beings. As we noted in the last chapter this is one of the principal problems in the evaluation of human risk, and we shall get back to it in the later chapters on risk assessment. For now, emphasis is on the selection of animal species and strains for their known reliability as experimental subjects. To put it in stark (but honest) terms - the animals are used as toxicity measuring devices. 

Toxicity measurements were performed in a classical way on DBA/2 mice and LDq was found to be 250 mg/kg. We may notice that MYKOMET 63 is about six times less toxic than MYKO 63. 

SOF, SOPHi and SOAz are soluble in water and could consequently by used in 0.9% NaCl water solution for both toxicity measurements and antitumoral tests DISOF, having very poor solubility in water, was inoculated as a suspension in 4 0 aqueous hydroxypropylcellulose (Klucel J. F. Hercules Co.). 

The type of measurement made, and hence the type of data treatment, depends on the requirements of the test. Thus, measurement of the percent response at the molecular level may be important mechanistically and more precisely measured. However, for the assessment of toxicity, measurement of the population response may be more appropriate. 

Chronic toxicity may be quantitated in a similar manner to acute toxicity, using the TD50 concept. Measurement of chronic toxicity in comparison with acute toxicity measurements may reveal that the compound is accumulating in vivo and may therefore give a rough approximation of the probable whole-body half-life of the compound. 

Cell Line Source Differentiated Cell Type Toxicant Measured End Point... 

Salizzato, M., Pavoni, B., Ghirardini, A.V. and Ghetti, P.F. (1998) Sediment toxicity measured using Vibrio fischeri as related to the concentrations of organic (PCBs, PAHs) and inorganic (metals, sulfur) pollutants, Chemosphere 36 (14), 2949-2968. 

Indices such as the SED-TOX and the PEEP have great appeal because their single value is easily grasped. However, they could sometimes be deceptive. An index could encompass a large number of toxicity measurements that provides an assessment of water or sediment quality, but indices need to be used cautiously because there is a loss of information in the calculation of one summary value. Results of individual toxicity tests should be examined for questionable results and endpoints that might skew the index. 

Large (or selected) number of trophic levels, toxicity measurements, endpoints and exposure routes... 

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