Toxicity s

Exposure to manganese dusts, fume, and compounds should not exceed the ceiling value of 5 mg/ms for even short periods because of the element s toxicity level. 

Historically, the annual consumption of nickel fluoride was on the order of a few metric tons. Usage is droppiag because nickel fluoride is Hsted ia the EPA and TSCA s toxic substance iaventory. Nickel fluoride tetrahydrate is packaged ia 200—500-lb (90.7—227-kg) dmms and the 1993 price was 22/kg. Small quantities for research and pilot-plant work are available from Advance Research Chemicals, Aldrich Chemicals, Johnson/Matthey, Pfalt2 and Bauer, PCR, and Strem Chemicals of the United States, Fluorochem of the United Kingdom, and Morita of Japan. 

AH nickel compounds are considered as suspected carcinogens and are Hsted in the EPA and TSCA s toxic substances inventory. LD q (mice iv) for... 

All the PMBs are Hsted on the U.S. EPA s Toxic Substances Control Act NonConfidential Chemical Substances Inventory (Table 8). In the early to mid-1980s, pseudocumene, mesitylene, hemimellitene, and trimethylbenzene were coveted by TSCA Section 8(a) Preliminary Assessment Information Rule (PAIR) reporting requirements (22) and by TSCA Section 8(d) for health and safety data (23). Mesitylene is the subject of a test rule subacute oral toxicity and subchtonic oral toxicity in tats were underway in 1994 (24). The Safe Drinking Water Act (SDWA) allows monitoring for pseudocumene and mesitylene at the discretion of the State (25). Of the PMBs, only pseudocumene is subject to SARA Tide III section 313 annual release reporting (26). 

Styrene is Hsted in the U.S. Toxic Substance Control Act (TSCA) Inventory of Chemicals. It is not confirmed as a carcinogen but is considered a suspect carcinogen. The recommended exposure limits are OSHA PEL 50 ppm, ACGIH TLV 50 ppm. For higher concentrations,... 

The submissions of section 313 reports in magnetic media and computer-generated facsimile formats has been approved by EPA. Magnetic media submissions to EPA must follow basic specifications set forth by EPA in the document. Magnetic Media Submissions Instructions fEPA 560/4-90-008) which is also included in EPA s Toxic Chemical Release Inventory Reporting Package for 1989 (EPA 560/4-90-001). To order these documents, see the document request form in Appendix I. 

Column 7 lists the type of hazard that is being considered. If the chemical i s toxic then the release and dispersion to the workers and public is the hazard. 

Figure 2.6.1 USEPA s Toxic Chemical Release Inventory Reporting Form.

The early promise of wide applications for beryllium has not materialised, despite improvements in purity and more efficient means of consolidation such as isostatic hot pressing, because of the metal s toxicity, brittleness and cost. It is now chiefly of interest in the specialised fields of aerospace and nuclear applications. BrushWellman is currently the sole commercial primary producer of beryllium metal in the West. 

The different oxidation states of a metal can have dramatically different chemical properties, which in turn affect their biogeochemical forms and significance. For example, almost 4 g/L ferrous iron, Fe(II), can dissolve in distilled water maintained at pFi 7.0. However, if the water is exposed to air and the iron is oxidized to Fe(III) essentially all the iron will precipitate, reducing the soluble Fe concentration by more than eight orders of magnitude. Oxidation state can also affect a metal ion s toxicity. For instance, the toxicity of As(III) results from its ability to inactivate enzymes, while As(V) interferes with ATP synthesis. The former is considerably more toxic to both aquatic organisms and humans. 

TRI99. 2001. TRI explorer Providing access to EPA s toxics release inventory data. Washington,... 

The preparation of 2,3,7,8-tetrachlorodibenzo-p-dioxin by chlorination of 2,7-dichlorodibenzo-p-dioxin yields a product containing significant quantities of trichloro- and pentachlorodibenzo-p-dioxins (11). Such mixtures are not amenable to separation on a preparative scale. Although 2,3,7,8-tetrachlorodibenzo-p-dioxin has been prepared by the pyrolytic condensation of sodium 2,4,5-trichlorophenate, this method is undesirable for preparation of 2,3,7,8-tetrachlorodibenzo-p-dioxin on the gram scale (2, 12). The pyrolytic reaction is difficult to control and the potential danger is enhanced by the product s toxicity. The salt was dissolved in bEEE [bis(2-ethoxyethyl) ether, bp 189°-190°C] and refluxed for 15 hours with the Ullmann catalyst. The desired product was obtained in 39% yield by condensation of potassium 2,4,5-trichlorophenate (Reaction 3). 

Palytoxin is hemolytic (4) and is an extremely potent toxin (7). We have shown that in rat liver cells palytoxin stimulates de-esterification of cellular lipids to liberate arachidonic acid (5). These rat liver cells metabolize this increased arachidonic acid via the cyclooxygenase pathway to produce prostaglandin (PG) I2 and lesser amounts of PGE2 and PGp2. Palytoxin acts on many cells in culture to stimulate the production of cyclooxygenase metabolites (Table I). Clearly, the myriad pharmacological effects of the arachidonic acid metabolites must be considered in any explanation of the many clinical manifestations of palytoxin s toxicity. 

Comparative Toxicokinetics. In humans, the targets for trichloroethylene toxicity are the liver, kidney, cardiovascular system, and nervous system. Experimental animal studies support this conclusion, although the susceptibilities of some targets, such as the liver, appear to differ between rats and mice. The fact that these two species could exhibit such different effects allows us to question which species is an appropriate model for humans. A similar situation occurred in the cancer studies, where results in rats and mice had different outcomes. The critical issue appears to be differences in metabolism of trichloroethylene across species (Andersen et al. 1980 Buben and O Flaherty 1985 Filser and Bolt 1979 Prout et al. 1985 Stott et al. 1982). Further studies relating the metabolism of humans to those of rats and mice are needed to confirm the basis for differences in species and sex susceptibility to trichloroethylene s toxic effects and in estimating human heath effects from animal data. Development and validation of PBPK models is one approach to interspecies comparisons of data. 

This manuscript benefited substantially from the comments provided by 3 anonymous reviewers. Funding support from the US Geological Survey s Toxics and Priority Ecosystems programs to D. Krabbenhoft, and from NSF grant No. 0451345 to C. Gilmour and R. Mason are greatly appreciated. 

The high-surface-area TUD-1 can serve as an anchor for many catalysts. Si- or Al-Si-TUD-1 (24,25) can be used as a support for various noble metals (Pt, PtPd, Ir, etc.). This will provide catalysts suitable for the hydrogenation of olefins and aromatics. In the refining industry, one use is the hydrogenation of polynuclear aromatics ( PNAs ) in diesel fuel, which can lower the fuel s toxic properties. Also, jet fuel has an aromatics constraint, designed to lessen smoke formation. Cracked stocks (e.g., coker or visbreaker liquids) generally have undesirable olefins (especially a-olefins) that also need to be saturated prior to final processing. 

Witschi, H. Lock, S. Toxicity of butylated hydroxytoluene in mouse following oral administration. Toxicology 1978, 9, 137-146. 

Closely monitor patients for efficacy and toxicity while they are receiving hydroxyurea. Monitor mean corpuscular volume (MCV) because it increases as the level of HbF increases. If the MCV does not increase with hydroxyurea use, the marrow may be unable to respond, the dose may not be adequate, or the patient may be noncompliant.27 HbF levels also can be monitored to assess response. Assess blood counts every 2 weeks during dose titration and then every 4 to 6 weeks once the dose is stabilized. Temporary discontinuation of therapy is warranted if the hemoglobin level is less than 5 g/dL (50 g/L or 3.1 mmol/L), the absolute neutrophil count is less than 2000/mm3 (2 x 109/L), platelets are less than 80,000/mm3 (80 x 109/L), or reticulocytes are less than 80,000/mm3 (80 x 109/L) if the hemoglobin is less than 9 g/dL (90 g/L or 5.6 mmol/L). Monitor for increases in serum creatinine and transaminases. Once the patient has recovered, hydroxyurea may be restarted with a dose that is 2.5 to 5 mg/kg less than the dose associated with the patient s toxicity. Doses then may be increased by 2.5 to 5 mg/kg daily after 12 weeks with no toxicity. 

Prior to the introduction of imatinib, the combination of interferon-alfa and low dose cytarabine was the nontransplant treatment of choice for patients in chronic phase CML. The precise mechanism of action of interferon-alfa remains unknown. The addition of cytarabine to interferon-alfa improves the response compared with interferon alone. This combination produces cytogenetic response rates of 30%, much lower than imatinib.13 One of the major drawbacks, in addition to the low response rates, is interferon s toxicity,... 

No broad study of tetraethyl lead was conducted. According to Kehoe, It was thought that these necessarily extensive studies should not be repeated at present, at public expense, but that they should be continued at the expense of the industry most concerned. Kehoe proudly declared later, The problem [of tetraethyl lead s toxicity] therefore was left to a very substantial extent in our hands, where it has remained ever since. Such cooperative arrangements were typical of the 1920s in lieu of direct government regulation, industrial groups volunteered to collect technical information about the air and water pollution they caused. 

Phetsombat, S., Kruatrachue, M., Pokethitiyook, P., and Upatham, S., Toxicity and bioaccumulation of cadmium and lead in Salvinia cucullata, Journal of Environmental Biology, 27 (4), 645-652, 2006. 

HCF was especially widely used in Western countries. Until 1972, it was included as an active component in soaps, cleansing creams, shampoo, deodorants, creams, and toothpastes. HCF was used for medical purposes, to control staphyllococcus contamination, in particular in maternity hospitals and in the cosmetics industry it was also used as a preservative, etc. It was used in agricultural formulations as well [67]. Although HCF s toxicity was... 

Ans. DDT s toxicity to insects is its useful property its toxicity to humans, birds, and other animals makes it undesirable. It is stable, that is, nonbiodegradable (does not decompose spontaneously to simpler substances in the environment). This property makes its use for insects alone more difficult. 

As these strategies are brought to fruition, there remains one related issue the determination of a smoke s potential harm per mass of material burned, i.e., the toxic potency of smoke. Accurate measurement of this key characteristic of fire smoke permits a more quantitative determination of the fire s toxic hazard which includes other factors as discussed below. Toxic potency assessment also tells us whether a small fire will produce smoke so toxic that only a small amount will kill. The presence of such "supertoxicants" has been a major topic of discussion within the fire community. 

I 12. The answer is b. (Hardman, pp 1264-1265J Dactinomycin s major toxicities include stomatitis, alopecia, and bone marrow depression. Bleomycin s toxicities include edema of the hands, alopecia, and stomatitis. Mitomycin causes marked bone marrow depression, renal toxicity, and interstitial pneumonitis. Plicamycin causes thrombocytopenia, leukopenia, liver toxicity, and hypocalcemia. The latter may be of use in the treatment of hypercalcemia. Doxorubicin causes cardiotoxicity, as well as alopecia and bone marrow depression. The cardiotoxicity has been linked to a lipid peroxidation within cardiac cells. 

The mechanisms of each hazardous chemical s toxic effects differ and depend on many factors. The majority of substances take effects... 

Pearson G. S. Toxic Chemical A Multinational Import Export System. The CBW Convention Bulletin, 34, Dec. 1996... 

---