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Aromatic amines benzidines

That the aromatic amine benzidine is mutagenic only at the TK locus in L5178Y TK+,/ cells. The most disturbing finding was that benzidine (detectable without metabolism by S9 mix) did not produce detectable DNA adducts (as shown by 32P-post-labeling) in L5178Y cells. Thus, the mechanism... [Pg.214]

A typical electrochemical reaction for an aromatic amine (benzidine) is shown in Figure 2. Most of the HPLC/EC work to date has been conducted using carbon working electrodes and thus the oxidative mode of the detector has been exploited (e.g. for benzidine) to the greatest extent. However, platinum and mercury have been used successfully for electroreducible species such as metal ions =/ and parathionC .). ... [Pg.413]

Gas chromatography has been applied to the determination of a wide range of organic compounds in trade effluents including the following types of compounds which are reviewed in Table 15.15 aromatic hydrocarbons, carboxylic acids aldehydes, non ionic surfactants (alkyl ethoxylated type) phenols monosaccharides chlorinated aliphatics and haloforms polychlorobiphenyls chlorlignosulphonates aliphatic and aromatic amines benzidine chloroanilines chloronitroanilines nitrocompounds nitrosamines dimethylformamide diethanolamine nitriloacetic acid pyridine pyridazinones substituted pyrrolidones alkyl hydantoins alkyl sulphides dialkyl suphides dithiocaibamate insecticides triazine herbicides and miscellaneous organic compounds. [Pg.337]

Azo Compounds Azo dyes are widely used in the food, pharmaceutical, cosmetic, textile, and leather industry. They are synthetic compounds characterized by one (monoazo) or several intramolecular N = N bonds. Azo dyes, if they are systemically absorbed, can be metabolized by the way of azoreductases of intestinal microflora by liver cells and skin surface bacteria. This metabolism leads to aromatic amines that can be hazardous. In the 1930s, some azo derivatives like 4-dimethyl aminoazoben-zene (Butter Yellow, Cl Solvent Yellow 2, Cl 11020) and o-aminoazotoluene were experimentally found to be directly carcinogenic to liver and bladder after feeding. Other complex azo dyes like Direct Black 38 or Direct Blue 6 (Figure 28) release the aromatic amine benzidine. Some examples of azo dyes metabolized in benzidine and benzidine-congeners are listed in Table 3. [Pg.923]

In this method, cyanide reacts with bromine water to form cyanogen bromide, CNBr, which then reacts with pyridine to yield glutaconic aldehyde. This aldehyde is condensed with an aromatic amine (benzidine) to form a red polymethine dye, which is the basis for determination of cyanide. The excess of bromine is reduced with As(III). The colour intensity reaches a maximum after 15 min, and remains constant for a further 30 min. [Pg.148]

The pyromellitic dianhydride is itself obtained by vapour phase oxidation of durene (1,2,4,5-tetramethylbenzene), using a supported vanadium oxide catalyst. A number of amines have been investigated and it has been found that certain aromatic amines give polymers with a high degree of oxidative and thermal stability. Such amines include m-phenylenediamine, benzidine and di-(4-amino-phenyl) ether, the last of these being employed in the manufacture of Kapton (Du Pont). The structure of this material is shown in Figure 18.36. [Pg.517]

Amines combust immediately when they are in contact with fuming nitric acid. The accidents described mainly involved aromatic amines (phenylamine, N-ethylaniiine, o-toluidine, xyiidines, benzidine) but also triethylamine. In the last case the ignition can take place at a temperature starting at -60°C. [Pg.290]

The carcinogenicity of aromatic amines, such as benzidine and 2-naph-thylamine, was first recognized by Rehn in the 1890s as an occupational hazard in the German dyestuffs industry. Compounds in this class induce... [Pg.5]

Dvorak V, Nemek I, Zyka J (1967) Electrochemical oxidation of some aromatic amines in acetonitrile medium II. benzidine, N,N,N ,N -tetramethylbenzidine, and 1,4-phenylene-diamine derivatives. Microchem J 12 324-349... [Pg.81]

Historically, bladder tumors have been associated with exposures in the aniline dye industry. However, conclusive evidence for any one particular exposure could not be obtained in these studies since the workers were exposed to many chemicals within the same work area. For example, Case et al. (1954) investigated the incidence of bladder tumors among British workers in the chemical dye industry. In addition to aniline, the workers were exposed to other aromatic amines, including a- and P-naphthylamine, benzidine, and auramine. Although exposures could not be quantified, there was insufficient evidence to suggest that aniline was a cause of bladder cancers. More recent studies indicate that P-naphthylamine, 4-aminodiphenyl, 4-nitrodiphenyl, 4,4-diaminodiphenyl, or o-toluidine may be involved in increased cancers in the dye industry (Ward et al. 1991 Benya and Cornish 1994). [Pg.41]

Limit values for primary aromatic amines, aromatic aminosulfonic acids, certain cancerogenic amines (e.g., benzidine, 2-naphthylamine, 4-aminobiphenyl and 2-methyl-4-chloroaniline) and for polychlorinated biphenyls (PCB) should be viewed in the listed references of the specific country. [Pg.591]

Fig. 3.61. HPLC-UV chromatogram at 230 nm for the analysis of the aromatic amines listed. (1) 1,4-Diaminobenzene (2) 2-chloro-l,4-diaminobenzene (3) 2,4-diaminotoluene (4) benzidine (5) 4,4 -oxidianiline (6) aniline and 4-nitroaniline (7) o-toluidine (8) 4,4 -methylenedianiline (9) 3,3 -dimethoxibenzidine (10) 3,3 -dimethylbenzidine (11) 4-chloroaniline and 2-amino-4-nitrotoluene (12) 4,4 -thiodianiline (13) p-cresidine (14) 2,4-dimethylaniline (15) 2-naphty-lamine (16) 4-chloro-o-toluidine (17) 4,4 -methylene-di-o-toluidine (18) 2,4,5-trimethylaniline (19) 4-aminobiphenyl (20) 3,3 -dichlorobenzidine (21) 4,4 -methylenbis (2-chloroaniline) and (22) o-aminoazotoluene. Reprinted with permission from M. C. Garrigos et al. [130]. Fig. 3.61. HPLC-UV chromatogram at 230 nm for the analysis of the aromatic amines listed. (1) 1,4-Diaminobenzene (2) 2-chloro-l,4-diaminobenzene (3) 2,4-diaminotoluene (4) benzidine (5) 4,4 -oxidianiline (6) aniline and 4-nitroaniline (7) o-toluidine (8) 4,4 -methylenedianiline (9) 3,3 -dimethoxibenzidine (10) 3,3 -dimethylbenzidine (11) 4-chloroaniline and 2-amino-4-nitrotoluene (12) 4,4 -thiodianiline (13) p-cresidine (14) 2,4-dimethylaniline (15) 2-naphty-lamine (16) 4-chloro-o-toluidine (17) 4,4 -methylene-di-o-toluidine (18) 2,4,5-trimethylaniline (19) 4-aminobiphenyl (20) 3,3 -dichlorobenzidine (21) 4,4 -methylenbis (2-chloroaniline) and (22) o-aminoazotoluene. Reprinted with permission from M. C. Garrigos et al. [130].
Fig. 3.154. Electropherogram for the working solution of aromatic amines. Peaks 1 = 4,4 -diamin-odiphenylmethane 2 = 4,4 -oxidianiline 3 = benzidine 4 = aniline 5 = 2,4-diaminoanisole 6 = 2,4 -toluilendiamine 7 = o-toluidine 8 = 3,3 -dimethylbenzidine 9 = 3,3 -dimethoxyben-zidine 10 = p-cresidine 11 = 2-naphtylamine 12 = p-chloroaniline 13 = 4-aminodiphenyl 14 = 1-naphtylamine 15 = 4-chlorotoluidine all at 10 ng/jul. Conditions buffer = 50 mM phosphate 10 per cent methanol pH = 3.1 fused-silica capillary recovered with polyamide, 52 cm X 75 pm i.d. applied potential = +22 kV UV detection at 214 nm. Reprinted with permission from S. Borros et al. [195]. Fig. 3.154. Electropherogram for the working solution of aromatic amines. Peaks 1 = 4,4 -diamin-odiphenylmethane 2 = 4,4 -oxidianiline 3 = benzidine 4 = aniline 5 = 2,4-diaminoanisole 6 = 2,4 -toluilendiamine 7 = o-toluidine 8 = 3,3 -dimethylbenzidine 9 = 3,3 -dimethoxyben-zidine 10 = p-cresidine 11 = 2-naphtylamine 12 = p-chloroaniline 13 = 4-aminodiphenyl 14 = 1-naphtylamine 15 = 4-chlorotoluidine all at 10 ng/jul. Conditions buffer = 50 mM phosphate 10 per cent methanol pH = 3.1 fused-silica capillary recovered with polyamide, 52 cm X 75 pm i.d. applied potential = +22 kV UV detection at 214 nm. Reprinted with permission from S. Borros et al. [195].
Baird, R., Carmona, L., and Jenkins, R.L. Behavior of benzidine and other aromatic amines in aerobic wastewater treatment, J. Water Pollut. Control Fed, A9(1) IG09-1615, 1977. [Pg.1628]

A vapor pressure of 4.5><10 mm Hg at 20 °C has been reported (DCMA 1989). Prior to OSHA 1974 regulations, benzidine and 3,3 -dichlorobenzidine were manufactured in open systems that permitted atmospheric releases of suspended particles at the work site (Shriner et al. 1978), but no historical data were located specifically for 3,3 -dichlorobenzidine emissions (atmospheric or in water). The absence of data may be attributed to analytical methods used at that time that could not distinguish benzidine from its derivatives or many other aromatic amines (Shriner et al. 1978). Under OSHA regulations adopted in 1974, only closed manufacturing systems are permitted, and atmospheric emissions are presumably reduced because of this regulation. [Pg.114]

Bimer G, Albrecht W, Neumann H-G. 1990. Biomonitoring of aromatic amines III. Hemoglobin binding of benzidine and some benzidine congeners. Arch Toxicol 64(2) 97-102. [Pg.152]

Bowman MC, Rushing CR. 1981. Trace-level determination of benzidine, 3,3 -dichlorobenzidine in animal chow wastewater and human urine. In Egan H, ed. Environmental carcinogens - selected methods of analysis. Volmne 4. Some aromatic amines and azo dyes in the general and industrial environment. Lyon, France International Agency for Research on Cancer, 159-174. [Pg.152]

Dyestuff workers exposed to BNA and benzidine before 1972 showed alterations in some T lymphocyte subpopulations some 20 years later. Specifically, there was a decreased number of circulating CD4f T lymphocytes in exposed workers. Measurement of this T lymphocyte subpopulation may provide a useful biological marker of past exposure to aromatic amines. [Pg.508]

A comparison of extraction methods for primary aromatic amines including 1,4-phenylenediamine, 2,4-diaminotoluene, benzidine, 4,4 -methylenebis (2-chloroanilme), 3,3 -dimethylbenzidine, and 3,3 -dichlorobenzidine from solid matrices was conducted. Supercritical fluid extraction (SEE) was evaluated and compared with the classical method, sonication extraction (Oost-dyk et al., 1993). [Pg.148]

Further complications of the reduction of aromatic nitro compounds are the possibility of complete reduction to aromatic amines (which may condense with nitroso compounds to give the desired azo compounds), reduction of azo compounds to the corresponding hydrazo compounds, followed by a benzidine (or semidine) rearrangement. It is clear, therefore, that the level of reducing agent used and other reaction conditions are quite critical. [Pg.165]

Aromatic amines as a compound class account for many of the known carcinogenic organic chemicals. Perhaps the most widely publicized compounds are benzidine and 3,31-dichlorobenzidine (DCB)(4>5)which until recently were widely used in the manufacture of dyestuffs. Another widely publicized suspected car-cinogenic aromatic amine is 4-methoxy-m-phenylenediamine (MMPDA)(6)which is used as an ingredient in many permanent hair dye formulations. 4,4,-methylenebis(2-chloroaniline) or MBOCA(Z)and 4,4-methylenedianiline (MDA) are widely used as curing agents in polyurethane resins and are said to be carcinogenic. ... [Pg.415]

Two experiments were conducted to study the utility of HPLC in determining aromatic amines in commercial dyes. In the first experiment a benzidine based dye, Direct Blue 6, and a commercial hair dye formulation containing Direct Blue 6 were analyzed for benzidine. In the second experiment a DCB based pigment (diarylide yellow) was analyzed for residual DCB. [Pg.419]

H.B. (1980) Metabolism ofhisazohiphenyl dyes derived from benzidine, 3, 3 -methylbenzidine and 3, 3 -dimethoxylbenzidine to carcinogenic aromatic amines in the dog and rat. Toxicol. Appl. Pharmacol. 56, 248—258. [Pg.406]

Some other aromatic amines such as benzidine and 4-aminobiphenyl are also carcinogenic to the bladder by the same mechanism. These amines have industrial uses and have been implicated in bladder cancer in exposed humans. [Pg.104]

Both NAT1 and NAT2 N-acetylate benzidine and O-acetylate the N-hydroxy metabolite. Because NAT2 and, to a lesser extent, NAT1 both show variation in the human population, this influences susceptibility to the carcinogenic effects of arylamines such as benzidine. With other aromatic amines, such as the heterocyclic amines found as food pyrolysis degradation products, N-acetylation is not favored, N-oxidation being the primary route followed by O-acetylation. This seems to take place in the colon. [Pg.113]


See other pages where Aromatic amines benzidines is mentioned: [Pg.384]    [Pg.249]    [Pg.369]    [Pg.384]    [Pg.249]    [Pg.369]    [Pg.273]    [Pg.23]    [Pg.194]    [Pg.825]    [Pg.775]    [Pg.75]    [Pg.38]    [Pg.262]    [Pg.61]    [Pg.137]    [Pg.1197]    [Pg.474]    [Pg.40]    [Pg.78]    [Pg.152]    [Pg.11]    [Pg.86]    [Pg.1265]    [Pg.22]    [Pg.90]    [Pg.400]   
See also in sourсe #XX -- [ Pg.188 , Pg.326 , Pg.328 , Pg.401 ]




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