Aromatic nitro compounds carcinogenic

We now illustrate the opposite case where the intermediate is in fact a highly undesirable substance, as it presents a health, or even explosion, hazard. The hydrogenation of aromatic nitro compounds, such as the one shown in Fig. 2.6, is industrially important for the production of dyes, whiteners, agrochemicals and pharmaceuticals. The reaction occurs in the presence of a platinum catalyst and proceeds via intermediates, among which the hydroxylamine (-NHOH) species is particularly hazardous, as it is both carcinogenic and explosive. Unfortunately, standard platinum catalysts give rise to high levels of this undesired intermediate. 

Tatsumi K, Kitamura S, Narai N. Reductive metabolism of aromatic nitro compounds including carcinogens by rabbit liver preparations. Cancer Res 1986 46(3) 1089-1093. 

The high-temperature reaction of aromatic amines with aromatic nitro compounds in the presence of base affords primarily an azo compound [39,40]. Because two independent laboratories have reported reasonable results with this synthesis, the procedure is given here. To be noted is that, while the reaction as described here involves 2-naphthylamine, a known carcinogenic intermediate, it is given only for reference to the procedure. Evidently, other aromatic amines also undergo the reaction. 

The most studied kinds of explosives are nitroaromatic explosives and their metabolites. Therefore, the emphasis of this review is on properties of nitroaromatic explosives, rather than propellants, pyrotechnics, or munitions, and their interactions with soils. Nitroaromatic explosives are toxic, and their environmental transformation products, including arylamines, arylhydroxyl-amines, and condensed products such azoxy- and azo-compounds, are equally or more toxic than the parent nitroaromatic [3]. Aromatic amines and hydroxylamines are implicated as carcinogenic intermediates as a result of nitrenium ions formed by enzymatic oxidation [4], Aromatic nitro compounds... 

A large number and variety of demonstrated carcinogens, including haloalkanes, quinones, benzenoid, and polynuclear aromatic hydrocarbons, aromatic nitro compounds, aromatic amines, metals, as well as other organic and inorganic compounds have been shown to fit these criteriaJ31l... 

By this directive, which is the 4th individual directive under framework directive 80/1107/EEC, 3 aromatic amines and one aromatic nitro compound, all showing strong carcinogenic properties, are banned [6-8]. This means that they must not be produced or used in the European member states. 

Aliphatic and aromatic nitro compounds are reduced at relatively positive potentials via the hydroxylamines to the corresponding amines. The carcinogenic 4-nitroquinoline-/V-oxide is determined by DPP in the presence of 4-hydroxyam-inoquinoline-/V-oxide and 4-aminoquinoline-/V-oxide via the reduction of the nitro group [79]. Nitrazepam, parathion, nitrofurantoin, and the ni-troimidazoles in blood plasma or urine are also determined via the reduction of the respective nitro groups. 

SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic data. Poison by ingestion. Moderately toxic by inhalation and possibly other routes. Experimental teratogenic and reproductive effects. A skin and severe eye irritant. Mutation data reported. A broad-spectrum herbicide. See also NITRO COMPOUNDS of AROMATIC HYDROCARBONS and ETHERS. When heated to decomposition it emits very toxic fumes of Cl" and NOx. 

DOT CLASSIFICATION EXPLOSIVE LID Label EXPLOSIVE LID SAFETY PROFILE Questionable carcinogen with experimental neoplastigenic data. Mutation data reported. A powerful and violent explosive used as a booster explosive its use is superior to TNT. It is not as good for this purpose as tetryl, but is extremely stable and much safer to handle. See also NITRO COMPOUNDS of AROMATIC HYDROCARBONS. 

SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic and neoplastigenic data. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx. See also NITRO COMPOUNDS OF AROMATIC HYDROCARBONS. 

DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE Confirmed carcinogen. A poison. Moderately toxic by ingesdon. Mucous membrane effects by inhalation. Mutation data reported. Combustible when exposed to heat or open flame. To fight fire, use water spray, fog, foam, CO2. Potentially explosive reaction with alkali (e.g., sodium hydroxide). When heated to decomposition it emits toxic fumes of NOx. See also other methylnitrobenzene entries and NITRO COMPOUNDS OF AROMATIC HYDROCARBONS. 

Some Aromatic Amines and Related Nitro Compounds - Hair dyes. Colouring Agents and Miscellaneous Industrial Chemicals, lARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volnme 16, lARC, Lyon, France, 1978, p.325. 

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