Mutagenic compound

Humic Substances, Mutagenic Compounds and Plant Species Used... 

The mutagenic compounds used with the corresponding abbreviations and concentrations used, are listed in Table 2. 

Eleven plant species (Table 3) were preliminarly tested for their response to the Feulgen staining method (described below), which is essential for the efficient microscope observation of genetic anomalies of cells. This, in order to select plants to be successively used in the experiments with the mutagenic compounds. 

Only four plant species, i.e., Vicia faba, Allium cepa, Pisum sativum and Triticum turgidum, responded adequately to the Feulgen procedure, and were considered for use in the successive experiments. These species, together with the corresponding mutagenic compounds used and the mutagenicity tests adopted (see below in Sect. 2.4.) are listed in Table 4. 

Table 2. Mutagenic compounds used with corresponding abbreviations and concentrations ...

Plant species Mutagenic compound Mutagenicity test... 

Some HS samples were also tested, either alone or in combination with some mutagenic compounds, for their possible antitoxic effect on the seedlings of some plant species. In particular (a) the sample ASHA at a concentration of 10 or 100 mg L-1, alone or in combination with 1 or 10 mg L 1 of ALA, was tested on T. turgidum and (b) samples SHHA, PHA, PFA, LHA, SHA and SFA at concentrations of 20 or 200 mg L-1, alone or in combination with 10 mg L 1 MH, were tested on V. faba. The antitoxic effect was evaluated by measuring some biometrical parameters such as... 

Kronberg L, Holmbom B, Reunanen M, Tikkanen L (1988) Identification and quantification of the Ames mutagenic compound 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone and of its geometric isomer (E)-2-chloro-3-(dichloromethyl) -oxobutenoic acid in chlorine-treated humic water and drinking water extracts. Environ Sci Technol 22 1097-1103... 

Schlatter, and F. E. Wurgler. The influence of roasting procedure on the formation of mutagenic compounds in coffee. Food Chem Toxicol 1985 23(6) 593-597. 

Box 10.9), a new class of mutagenic compounds was discovered, the nitroarenes. Within a short time, they were identified as directly mutagenic copollutants present along with well-known promutagenic PAHs in combustion-generated emissions and distributed worldwide in urban ambient air (see Section D). 

An interesting aspect of the long-range transport of mutagenic compounds is a field study by De Pollok and co-workers (1997), who collected and measured ambient air particles at three different levels of a TV tower (surface, <1 m mid, 240 m, and top 433 m) near... 

Simula, T.P, Glancey, M.J. Wolf, C.R. (1993) Human glutathione S -transferase-expressing Salmonella typhimurium tester strains to study the activation/detoxification of mutagenic compounds studies with halogenated compounds, aromatic amines and aflatoxin Bp Carcinogenesis, 14, 1371-1376... 

The XAD procedure was selected on the basis of the comparison of results of complementary methods as mentioned earlier because it is effective in concentrating toxic as well as mutagenic compounds from Rhine water. The investigation demonstrates the application of short-cut biological methods needed for water quality control and complementary to chemical monitoring techniques. 

Considerable information of a general nature is available for uncontaminated water subject to the production of disinfection byproducts. The mutagens produced by drinking water chlorination appear to be numerous, but they exist either at low levels or are of low potency. For both the unresolved mixtures and for the few mutagenic compounds thus far identified, activity is readily reduced or destroyed by treatment with alkali or 4-nitrothiophenol and may be removed by GAC treatment. From water sources subject both to mutagen formation via disinfection and to periodic contamination by toxic chemicals, experimental full-scale GAC treatment systems have provided mutagen-free water. 

Concentrated extracts of many drinking waters in the United Kingdom and elsewhere are mutagenic as observed in bacterial assays (i-3). Compounds that are widely distributed in the aquatic environment, such as humic substances and amino acids, have been found to react with chlorine to produce mutagenic compounds (4, 5). These compounds may account for at least some of the mutagenic activity of extracts of drinking waters. 

Two approaches to the identification of mutagenic compounds in drinking water are described in this chapter. The first involves HPLC fractionation of extracts of treated water combined with mutagenicity testing of the fractions. Fractions of a mutagenic extract of chlorinated water were compared with nonmutagenic fractions of the same water sampled before final chlorination to focus on differences between the two, especially substances present only in mutagenic extracts and fractions. 

HPLC Fractionation of Extracts of Treated Water. Capillary GC-MS analysis of the XAD-2/ethyl ether extracts of water sampled before and after final chlorination showed no significant difference that could account for the mutagenic activity observed after chlorination. These results indicate that the mutagenic compounds present in the extracts of drinking water are not readily amenable to analysis by GC-MS. However, the possibility cannot be excluded that the mutagenic compounds were present below the detection limit or that they were masked by other compounds. 

Therefore, separation and fractionation of the extracts were carried out by using HPLC in combination with mutagenicity testing to try to isolate fractions containing mutagenic compounds. Identification of the mutagenic compounds in these fractions can then be attempted by using... 

Chlorination of Individual Amino Acids. HPLC analysis of an extract of chlorinated humic acids indicated that the chlorination products compose a highly complex mixture of organic material. Thus, the task of identification of mutagenic products of chlorination would not be simplified by the use of the humic acid model. In contrast, the amino acid model of production of mutagenic compounds can be readily simplified by the use of individual compounds as precursors. 

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