Animals and Humans

Ozone, known for its beneficial role as a protective screen against ultraviolet radiation in the stratosphere, is a major pollutant at low altitudes (from 0 to 2000 m) affecting plants, animals and human beings. Ozone can be formed by a succession of photochemical reactions that preferentially involve hydrocarbons and nitrogen oxides emitted by the different combustion systems such as engines and furnaces. 

The nervous systems and especially the brains of animals and humans work very fast, efficiently, and highly in parallel. They consist of networked neurons which work together and interchange signals with one another. This section describes the functionality of a biological neuron and explains the model of an artificial neuron. 

The physical state of a pollutant is obviously important a particulate coUector cannot remove vapor. Pollutant concentration and carrier gas quantity ate necessary to estimate coUector si2e and requited efficiency and knowledge of a poUutant s chemistry may suggest alternative approaches to treatment. Emission standards may set coUection efficiency, but specific regulations do not exist for many trace emissions. In such cases emission targets must be set by dose—exposure time relationships obtained from effects on vegetation, animals, and humans. With such information, a Ust of possible treatment methods can be made (see Table 1). 

Oral LD q levels have been deterrnined in the mouse at 470 mg/kg (21) and the guinea pig at 7750 mg/kg (22). Several other studies (23—25) have shown that large quantities of both synthetic and natural glycerol can be adniinistered orally to experimental animals and humans without the appearance of adverse effects. Intravenous adniinistration of solutions containing 5% glycerol to animals and humans has been found to cause no toxic or otherwise undesirable effects (26). 

For dmgs approved originally between 1938 and 1962, the FDA has utilized the Abbreviated New Dmg AppHcation (ANDA) for review of generic products that are pharmaceutical equivalents of the initially approved products. In this way, costiy dupHcation of animal and human experimentation is avoided. The new manufacturer has to show only that its manufacturing methodology, specifications, quaUty control, and labeling are acceptable. In some cases, the FDA does require proof of bioequivalence. 

X Bq of Pu has been released, mostiy from bum-up of the nuclear powered sateUite SNAP-9a and that 3.7 X 10 Bqof + ° Pu was released by the Chernobyl accident (167,168). Many studies have been done to determine the cumulative fallout on sods, plants, bodies of water, animals, and humans. For example, the cumulative Pu fallout ia forest and grasslands and ia the Hver of elderly humans ia Bavaria, Germany are approximately... 

Approximately half of the iodine consumed is used to make potassium iodide (see Iodine and iodine compounds). Production of KI is almost 1000 t/yr. Its main uses are in animal and human food, particularly in iodized salt, pharmaceuticals (qv), and photography (qv). 

The pharmacological profile of buspirone in both animals and humans differs substantially from that of the ben2odia2epine anxiolytics. Buspirone lacks anticonvulsant, myorelaxant, and hypnotic effects. It also produces less sedation resulting in less psychomotor impairment in conjunction with... 

There are areas (22) where selenium levels in the soil are very low these include regions of volcanic activity like that adjacent to the Cascade mountains in the Pacific Northwest states of the United States and the central north island of New Zealand. There, because the heat of emption volatilized the selenium, the residual soil parent material is virtually devoid of selenium. Other areas of low soil-selenium reflect leaching of selenium out of the top soil, as in the Canterbury plain on New Zealand s south island. Areas of selenium deficiency have negative implications for animal and human health. 

Selenium deficiency has been identified iu humans iu a broad area of China, stretching from the northeast to the southwest. Two syndromes are evident Keshan disease, an endemic cardiomyopathy which affects children, and Kashin-Beck disease, an edemic osteoarthropathy (big-joiat), also mainly involving children, which occurs iu eastern Siberia and parts of China. As a result of these observations, a protective effect for selenium has been proposed, and various selenium-containing preparations have been appHed to preserve animal and human health. 

An important function of certain carotenoids is their provitamin A activity. Vitamin A may be considered as having the stmcture of half of the P-carotene molecule with a molecule of water added at the end position. In general, all carotenoids containing a single unsubstituted P carotene half have provitamin A activity, but only about half the activity of P carotene. Provitamin A compounds are converted to Vitamin A by an oxidative enzyme system present in the intestinal mucosa of animals and humans. This conversion apparendy does not occur in plants (see Vitamins, VITAMIN a). 

Chlorine. Chlorine, the material used to make PVC, is the 20th most common element on earth, found virtually everywhere, in rocks, oceans, plants, animals, and human bodies. It is also essential to human life. Eree chlorine is produced geothermally within the earth, and occasionally finds its way to the earth s surface in its elemental state. More usually, however, it reacts with water vapor to form hydrochloric acid. Hydrochloric acid reacts quickly with other elements and compounds, forming stable compounds (usually chloride) such as sodium chloride (common salt), magnesium chloride, and potassium chloride, all found in large quantities in seawater. 

Methylcobalamin and adenosylcobalamin are the two coen2yme forms of vitamin B 2 in animals and humans. Each is involved in the catalysis of a specific... 

Vitamin E can also act as an antioxidant (qv) in animals and humans alone or in combination with vitamin C (qv). Both are good free-radical scavengers with the vitamin C acting to preserve the levels of vitamin E (35). Vitamin E in turn can preserve the levels of vitamin A in animals (13). It has been shown that vitamin E reduces the incidence of cardiovascular disease (36—39). This most likely results from the antioxidant property of the vitamin which inhibits the oxidation of low density Hpoproteins (LDLs) (40—42). The formation of the oxidized LDLs is considered important in decreasing the incidence of cardiovascular disease (43). 

The recommended daily allowance for vitamin E ranges from 10 international units (1 lU = 1 mg all-rac-prevent vitamin E deficiency in humans. High levels enhance immune responses in both animals and humans. Requirements for animals vary from 3 USP units /kg diet for hamsters to 70 lU /kg diet for cats (13). The complete metaboHsm of vitamin E in animals or humans is not known. The primary excreted breakdown products of a-tocopherol in the body are gluconurides of tocopheronic acid (27) (Eig. 6). These are derived from the primary metaboUte a-tocopheryl quinone (9) (see Eig. 2) (44,45). 

Vimses contain either RNA or DNA, and this nucleic acid composition forms the basis for thek classification. Although vimses ate known to infect bactetia, insects, plants, animals, and humans, this discussion is restticted to the important vimses of vertebrates. The relevant vimses ate summarized in Table 2, using the nomenclature and taxonomy recommended by the International Committee on Taxonomy of Vimses (4,5). 

Human sensitization studies were negative at 10% solution (47). Undiluted benzyl alcohol produces moderate dermal irritation in guinea pigs and mild dermal irritation in rabbits (48,49). Severe eye irritation was noted in a rabbit study (50). Acute oral rat LD q values were reported between 1.23 and 3.10 g/kg (50—52). A dermal rabbit LD q value of 2.0 g/kg has been reported (49). Rats died after 2 h when exposed to a 200-ppm vapor concentration (53). Benzyl alcohol is readily oxidized in animals and humans to benzoic acid [65-85-0] which is then conjugated with glycine [56-40-6], and rapidly eliminated in the urine as hippuric acid [495-69-2] (54). 

Animal and Human Toxicity. The acute toxicity of lindane depends on the age, sex, and animal species, and on the route of adrninistration. The oral LD q in mice, rats, and guinea pigs is 86, 125—230, and 100—127 mg/kg, respectively. In contrast, most of the other isomers were considerably more toxic (94,95). Some of the other toxic responses caused by lindane in laboratory animals include hepato- and nephotoxicity, reproductive and embryotoxicity, mutagenicity in some short-term in vitro bioassays, and carcinogenicity (80). The mechanism of the lindane-induced response is not known. Only minimal data are available on the mammalian toxicides of hexachlorocyclopentadiene. 

Some skin sensitization to low molecular-weight DGEBPA resins (mol wt - 340) has been shown in animals and humans. Skin sensitization decreases with an increase in molecular weight but the presence of low molecular-weight fractions in the advanced resins may present a hazard to skin sensitization (43). 

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