Toxicological aspects

The first scientists to assess the toxic properties of silicones were from Dow Corning, a leading manufacturer. In studies with laboratory animals, liquid methyl and methyl phenol polysiloxane derivatives were found toxic after oral application, even in small quantities. At the same it was observed that low molecular weight linear PDMS, termed hexamethyl-disiloxane (HMDS) with a viscosity of 0.65 cSt (Tables 16.1 and 16.2), caused mild stupefaction and CNS disturbances, which indicated its absorption from the alimentary tract. Moreover, HMDS induced inflammatory conditions and necrosis in the sites of subcutaneous injections, whereas after intraperitoneal (IP) use it was lethal for some animals [24]. In the 1940s, both Both Rowe and Kernand, and Barondes in 1950, who were leading simultaneous investigations, observed temporary conjunctival irritation (conjunctivitis) 

In Table 16.3, the most frequently mentioned (based on ca. 400 scientific sources) pathological symptoms caused by the presence of linear and cyclic polysiloxanes in vivo are listed. It has been shown that silicone-tissue interactions are the cause of both minor health problems—such as irritation, headache, skin reactions, chronic fatigue syndrome—and very serious diseases, such as rheumatoid arthritis, systemic 

Migration in the body granulomatous inllcunmation of the genital area distribution to vtuious orgcuis accumulation in organs (brain, spinal cord) oncogenic properties [24,48,49,52-57] 

Proteins conformational change of myoglobin, fibronectin and fibrinogen adsorption of plasma proteins (immunoglobulins IgG, albumin, and fibronectin) on the surface of silicone implants and prostheses [52,58-60] 

Biodegradation biodegradabihty diffusion of low molecular weight products through cell barriers into the blood, migration and accumulation in the liver [61-65] 

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Summer KH, Kiein D, Griem H (2003) Ecological and toxicological aspects of mono- and disubstituted methyl-, butyl-, octyl-and dodecyltin compounds— Update 2002. GSF Nationai Research Center for Environment and Heaith, Neuherberg, for the Organotin Environmentai Programme (ORTEP) Association, December. 

MADAHAVi D L and SALUNKHE D K (1995) Toxicological aspects of food antioxidants , in Madavi D L, Deshpanda S S and Salunkhe D , Food Antioxidants, New York, Marcel Dekker Inc, 267. 

Ueno, Y. (ED) "Trichothecenes - Chemical, Biological, and Toxicological Aspects" Kodensha Scientific, Tokyo, 1983. 

A discussion of the results reported should take into consideration both the pharmacological and toxicological aspects per se, and their interpretation in terms of the health hazards presented by parathion. 

Muller, J. et al. (2008) Structural defects play a major role in the acute lung toxicity of multiwall carbon nanotubes toxicological aspects. Chemical Research in Toxicology, 21 (9), 1698-1705. 

Ecological and toxicological aspects of silver are reviewed by Smith and Carson (1977), the U.S. Environmental Protection Agency [USEPA] (1980, 1987), Lockhart (1983), the U.S. Public Health Service [USPHS] (1990), Andren et al. (1993, 1994), Andren and Bober (1995), Eisler (1996), Mukheqee (1997), and Ratte (1999). 

Smith, H.G., Jr. and R.L. Goulding. 1970. Toxicological aspects of three organophosphorus compounds (cythioate, famphur, and fenthion) in the host-ectoparasite system. Jour. Econ. Entomol. 63 1640-1646. 

Detailed information on ecological and toxicological aspects of fenvalerate and other synthetic pyrethroid insecticides is provided in reviews by Elliott (1977), Elliott and Janes (1978), Wouters and Bercken (1978), Glickman and Casida (1982), Vijverberg and Bercken (1982), Gray and Soderlund (1985), Leahey (1985), Smith and Stratton (1986), Coats et al. (1989), Bradbury and Coats (1989a), and Eisler (1992). 

Eisler, R. 1995. Ecological and toxicological aspects of the partial meltdown of the Chernobyl nuclear plant reactor. Pages 549-564 in D.J. Hoffman, B.A. Rattner, G.A. Burton, Jr., and A.J. Cairns, Jr. (eds.). Handbook of Ecotoxicology. Lewis Publ., Boca Raton, FL. 

POLTOX also contains two other useful data bases Toxline (described earlier) and the Food Science and Technology Abstracts (FSTA) libraries. The FSTA component is a reasonably comprehensive collection of information regarding toxicological aspects of compounds found in food, including contamination, poison, and carcinogenic properties. The CD-ROM product is available from Compact Cambridge, 7200 Wisconsin Avenue, Bethesda, MD 20814. 

The are several clearance and toxicological aspects that have to be considered in the drug discovery process such as metabolic stability, enzyme selectivity, CYP inhibition and type of inhibition. Among these factors, the prediction of the site of metabolism has become one of the most successful parameters for prediction. The knowledge of the site of metabolism enhances the opportunity to chemically modify the molecule to improve the metabolic stability. There are several approaches based on database mining, chemical reactivity, protein interaction or both that have been developed for the prediction of this property, with different degree of success and applicability. 

Maurel, P. (1996) The CYP3A family, in Cytochrome P450 Metabolic and Toxicological Aspects, (ed. Ioannides C.) CRC Press, Boca Raton, FL, pp. 241-270. 

In this chapter we consider, above all, the most recent developments of biological and toxicological aspects of fullerene and related compounds of the last few years, considering that many reviews and books cover this topic up to 2006 (Jensen et al., 1996 Nakamura et al., 1996 Da Ros and Prato, 1999 Tagmatarchis and Shinohara, 2001 Bosi et al., 2003 Nakamura and Isobe, 2003 Sarova et al., 2006 Bianco and Da Ros, 2007). 

Fishbein, L. An overview of environmental and toxicological aspects of aromatic hydrocarbons. III. Xylene, Sci. Total Environ., 43(1/2) 165-183, 1985. 

PVC-DEHP material systems ate incomparably cheap due to their high market volumes. At the same time, DEHP is one of the best examined substances on the European market from a toxicological aspect, although no greater assessment safety has been created as a result of this in the past 25 years ( The demand for toxicological certainties consolidates a lock-in in the case of high-volume existing substances - Hypothesis 3). 

With regard to biodurability the resistance of the fibres to elimination mechanisms in the lung is decisive from a toxicological aspect. Biosolubility is an essential parameter for this. 

The substitution of chemical solvents by water in paint and coating systems and also in cleaning processes creates complex evaluation issues, as the number of the various chemical components contained in the corresponding products generally increases. In addition, the release of persistent substances into the aquatic environment tends to be favoured by this. This therefore raises the question for assessing two suitable strategies containment of known hazardous substances in closed systems or substitution of the mobile solvent by complex water-based systems that are scarcely evaluable from a toxicological aspect. 

We will now examine in more detail some of the physiological and toxicological aspects of reproduction, pregnancy, and development. 

Musil J, Knotek Z, Chalupa J, et al. 1964. Toxicologic aspects of chlorine dioxide application for the treatment of water containing phenols. Sb Vys Sk Chem Technol Praze Oddil Fak Technol Paliv Vody 8 327-345. 

Hlmsworth, H., Chairman. Report of the Enquiry Into the Medical and Toxicological Aspects of CS... 

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