Medicines toxicity

Metabolite measurements have been used to assess health for decades, and so metabolomics is not a revolutionary approach to medicine, toxicity or nutri-... 

This is chiefly a tropical family of twining shrubs with no great importance other than the use of a few species as liber or medicinal/ toxic preparations at local levels. 

There are three major obstacles that may limit the usefulness of polycarboxylates, polynucleotides and the tilorone congeners in clinical medicine toxicity, hyporeactivity and immunogenicity. The problem of immunogenicity has been most thoroughly investigated with ds-RNAs such as poly(I) poly(C). Injected parenterally into rabbits, poly(I) po y(C) and poly(A) poly(U) elicited the production of antibodies reactive with the ds—RNA 191 19S). 

Medicinal creosote is a mixture of phenols, chiefly guaiacol and creosol (4-melhyl-2-meth-oxyphenol), obtained by distillation of wood tar. B.p. 480-500 K. It is almost colourless with a characteristic odour and is a strong antiseptic, less toxic than phenol. 

CioHjjNOi. White crystals, m.p. 137-138°C. Prepared from phenol, via />-nitro-phenol, p-nitrophenetole and /7-phenetidine. It is used medicinally as an antipyretic analgesic similar to aspirin. It has chronic toxicity towards the kidney. 

Antibiotics are toxic water-solubie compounds produced by molds or bacteria which inhibit the growth of other microorganisms. For an antibiotic to be useful in medicine it should have a high order of selective toxicity to microorganisms which are pathogenic to man. Al-... 

Tetracyclines are produced by various Streptomyces strains and are extensively applied in human and veterinary medicine. They display a broad spectrum of antimicrobial activity in combination with low toxicity and can be applied orally. The most commonly prescribed tetracycline drugs are tetracycline itself and oxytetracycline, an oxygenated derivative, which are directly isolated from fermentation liquors, and doxycycline whose partial synthesis from oxy-... 

The Du Pont HaskeU Laboratory for Toxicology and Industrial Medicine has conducted a study to determine the acute inhalation toxicity of fumes evolved from Tefzel fluoropolymers when heated at elevated temperatures. Rats were exposed to decomposition products of Tefzel for 4 h at various temperatures. The approximate lethal temperature (ALT) for Tefzel resins was deterrnined to be 335—350°C. AH rats survived exposure to pyrolysis products from Tefzel heated to 300°C for this time period. At the ALT level, death was from pulmonary edema carbon monoxide poisoning was probably a contributing factor. Hydrolyzable fluoride was present in the pyrolysis products, with concentration dependent on temperature. 

See pubhcations of R. LiUs for additional studies related to the toxicity of lead following occupational exposure. These pubHcations have been compiled into a volume entitied Studies on Eead Exposed Occupational Groups 1967—1989 and ate available from the Dept, of Community Medicine, Mount Sinai School of Medicine, New York, 1991. 

The toxic effects of mercury and mercury compounds as well as their medicinal properties have been known for many centuries. In the first century AD, Pliny indicated the use of mercuric sulfide (cinnabar or vermilion) in medicine and in cosmetics. This compound was probably known to the Greeks in the time of Aristotle (13). 

In general, methacrylate polymers are considered nontoxic. In fact, various methacrylate polymers are used in food packaging (qv) and handling, in dentures and dental fillings (see Dental materials), and as medicine dispensers and contact lenses. However, care must be exercised because additives or residual monomers present in various types of polymers can display toxicity. For example, some acryHc latex dispersions can be mild skin or eye kritants. This toxicity is usually ascribed to surfactants in the latex and not to the polymer itself. 

Some elements found in body tissues have no apparent physiological role, but have not been shown to be toxic. Examples are mbidium, strontium, titanium, niobium, germanium, and lanthanum. Other elements are toxic when found in greater than trace amounts, and sometimes in trace amounts. These latter elements include arsenic, mercury, lead, cadmium, silver, zirconium, beryUium, and thallium. Numerous other elements are used in medicine in nonnutrient roles. These include lithium, bismuth, antimony, bromine, platinum, and gold (Eig. 1). The interactions of mineral nutrients with... 

Fig. 1. Periodic Table showing elements of importance in biological systems principal element of bioorganic compounds essential mineral nutrients for humans and other animals 1 essential mineral nutrient for animals, probably for humans M present in body, not known to be a nutrient or toxic element M element used in medicine element generally poisonous and present in body, possibly toxic.

National Library of Medicine, NIOSH s Registy of Toxic Effects Chemical Substances (RTECS) database, Nov. 1994 rev. the data have not been critically evaluated. 

Selenium plays a dual role in a living organism, depending on the compound and the amount adsorbed. Controlled small doses of some compounds are used in medicine and as diet supplements, for example, ca 0.1 ppm of diet dry matter for Hvestock (see Feed additives Mineral nutrients). Larger amounts can be toxic. 

Health and Safety Factors. The LD q of anhydrous sodium thiosulfate for mice is 7.5 0.752 g/kg (40). Because of low toxicity, it can be safely used iu veterinary medicine. Sodium thiosulfate pentahydrate is affirmed as a GRAS indirect and direct human food ingredient under the Federal Food, Dmg, and Cosmetic Act (41) (see Food additives). 

Carbarsone (Amebarsone) was once widely used for the treatment of intestinal amebiasis. Like other arsonic acids, however, carbarsone may cause skin rashes and even damage to the vision. Although it is stiU available for medicinal use, it is really obsolete as an amebicide because less toxic and more effective nonarsenicals are now available (174). 

Because of its extreme insolubiUty, barium sulfate is not toxic the usual antidote for poisonous barium compounds is to convert them to barium sulfate by administering sodium or magnesium sulfate. In medicine, barium sulfate is widely used as an x-ray contrast medium (see Imaging TECHNOLOGY X-RAY technology). It is also used in photographic papers, filler for plastics, and in concrete as a radiation shield. Commercially, barium sulfate is sold both as natural barite ore and as a precipitated product. Blanc fixe is also used in making white sidewall mbber tires or in other mbber appHcations. 

Animals which are fed extensively can encounter a vast array of compounds of varying medicinal and toxic potency and susceptibilities to degradation or detoxihcation a number of texts can be consiilted. ... 

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