Substance toxic

Substances which have fatal effects or cause severe health problems in low doses are classified as toxic. Toxic compounds are labeled with the dedicated R-phrase and the hazard symbol skuU-and-crossbones T with the hazard specification toxic . The exact criteria are summarized in Table 3.3. 

Substances which lead to severe, non-lethal health effects on an acute exposure in the same doses as those mentioned in Table 3.3 are also classified as toxic. To distinguish them from the lethal effects, they are classified with the R-phrase R 39/. In order to distinguish them from very toxic substances, the R-phrases for toxic have to follow the R 39, as can be seen in the following example  

R 39/24 Toxic danger of very serious irreversible effects in contact with skin. 

If serious health damage can be activated not by an acute, but by a repeated or longer-period exposure to doses in the same range as those described in Table 3.5, labeling with R 48 is stipulated. In contrast to the exact hmit values for the acute toxicity in Table 3.3, the doses mentioned in Table 3.5 serve as orientation values for the classification. 

R48/ Danger of serious damage to health on prolonged exposure. 

Recommendations define toxic substances as substances liable either to cause death or serious injury or to harm human health if swallowed or inhaled or brought into contact with the skin c). Indices of hazardous properties of toxic substances include carcinogenicity and mutagenicity as well as LCso, LDs and TLV. All TLV based values listed in Sect. 1.3.2 are implied here. In Japan, these toxic substances are regulated by the Toxic and Deleterious Substances Control Law. 

This chapter also covers blood-borne pathogens, a source of real diseases and concern for everyone who becomes involved in emergency response and emergency medical care. 

There are numerous government regulations addressing chemical hazards. Some of them, to name just a few, are  

Attempts have been made to determine the dosages of toxicants that cause injury to the normal (nonallergic) adult, but this has met with limited success. Generally, the greater the toxicity of the substance, the faster the rate of absorption, and the warmer the temperature, the more rapid the occurrence of the injury. In addition to individual susceptibility, other conditions affect the severity of the injury caused by the toxin. These other conditions are the  

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Combustion in an incinerator is the only practical way to deal with many waste streams.This is particularly true of solid and concentrated wastes and toxic wastes such as those containing halogenated hydrocarbons, pesticides, herbicides, etc. Many of the toxic substances encountered resist biological degradation and persist in the natural environment for a long period of time. Unless they are in dilute aqueous solution, the most effective treatment is usually incineration. 

Talaromycin A (a toxic substance produced by a fungus that grows on poultry house litter)... 

DDT resistant insects have the ability to convert DDT to a less toxic substance called DDE The mass spectrum of DDE shows a cluster of peaks for the molecular ion at m/z 316 318 320 322 and 324 Suggest a reasonable structure for DDE... 

Tests with animals have revealed that dioxin is one of the most toxic substances known Toward mice it IS about 2000 times more toxic than strychnine and about 150 000 times more toxic than sodium cyanide Fortunately however available evidence in dicates that humans are far more resistant to dioxin than are test animals and so far there have been no human fatalities directly attributable to dioxin The most prominent short term symptom seen so far has been a severe skin disorder known as chloracne Yet to be determined is the answer to the question of... 

There are three types of TAP emissions continuous, intermittent, and accidental. Both routine emissions associated with a batch process or a continuous process that is operated only occasionally can be intermittent sources. A dramatic example of an accidental emission was the release of methyl isocyanate [624-83-9] in Bhopal, India. As a result of this accident, the U.S. Congress created Tide III, a free-standing statute included in the Superfund Amendments and Reauthorization Act (SARA) of 1986. Title III provides a mechanism by which the pubHc can be informed of the existence, quantities, and releases of toxic substances, and requires the states to develop plans to respond to accidental releases of these substances. Eurther, it requires anyone releasing specific toxic chemicals above a certain threshold amount to aimuaHy submit a toxic chemical release form to EPA. At present, there are 308 specific chemicals subject to Title III regulation (37). 

The Toxic Substances Eist 1974 ed., U.S. Dept, of Health, Education Welfare, National Institute for Occupational Safety Health, Rockville, Md., June 1974. 

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... 

H. E. Christensen, Toxic Substances Eist, NIOSH, RockviUe, Md., 1972. 

Table 5. Grignard Reagents Listed on the U.S. EPA Toxic Substances Control Act (TSCA) List...

U.S. EPA, National Pesticide Survey Phased Report, Offiice of Water, Office of Pesticides and Toxic Substances, EPA 570/9-90-015, U.S. Govt. Printing Office, Washington, D.C., 1990. 

Health and Safety Executive, Monitoring Strategies for Toxic Substances, Guidance Note EH 42, HSE, Boode, Meseyside, U.K., 1989. 

ISI is available in hard copy and electronically at EPA s headquarters and regional Hbraries, and through the National Technical Information Service (NTIS). The electronic form may be installed on IBM PC-compatible computers or placed on local area networks, and mn under Microsoft WINDOWS or WordPerfect s Library program. The Macintosh version is no longer available. The 1993 update will include the ISI hardcopy, PC disks, and the PC system user manual. EPA also pubHshes ACCESS EPA, which provides sources of information, databases, and pubHcations within the EPA. Chapter 5 of that pubhcation includes important environmental databases in air and soHd waste, pesticides and toxic substances, water, and cross-program (110). EPA also provides databases accessible through EPA Hbraries, which describe the private EPA and commercial databases available to Hbrary users (111). 

Waste Treatment. Environmental concerns have increased the need to treat Hquid discharges from all types of industrial processes, as well as mnoffs where toxic substances appear as a result of leaks or following solubilization (see Wastes, industrial). One method of treatment consists of an ion-exchange system to remove the objectionable components only. Another involves complete or partial elimination of Hquid discharges by recycling streams within the plant. This method is unacceptable unless a cycHc increase in the impurities is eliminated by removing all constituents prior to recycling. 

Toxic substances adsorbed on resins are removed during a regeneration procedure. The resulting spent regeneration solution has a higher concentration of the toxic substance than the stream from which it was removed by the resin. Toxic material in the spent regenerating solution can usually be precipitated, electrodeposited as in an electrolytic ceU, or made insoluble by other acceptable procedures. 

The latest government regulations set forth under the Toxic Substances Control Act and in PubHc Health Service pubHcations should be checked before formulating new lubricants. Users of lubricants should request Material Safety Data Sheets for each substance involved plus certification of compliance from vendors. Lubricant compounders should insist on similar information from their suppHers for any additive packages. Manufacturers of both additives and lubricants commonly make toxicity checks on commercial products. 

Toxic Substances Control Act, Public Law No. 469, 94th U.S. Congress Chemical Substance Inventory, U.S. Environmental Protection Agency, Office of Toxic Substances, Wasliiagton, D.C., 1975. 

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