Mutagenicity and genotoxicity assessments of some industrially processed meat products in Algeria.

Processed meat products are presumptive sources of mutagens and genotoxins for consumers. Several epidemiological studies have reported that these products' high intakes have a positive link with cancer incidence. In Algeria, industrially processed meat products are widely consumed. However, there are no earlier studies involving their genotoxic activity. For this end, the current study aimed at evaluating the mutagenicity and the genotoxicity of some representative industrially processed meat products sold in popular supermarkets. All samples were extracted by established method, using both polar and non-polar solvents. The meat extracts mutagenicity was assessed by Ames test, using four strains of Salmonella typhimurium in the presence and absence of metabolic activation, and subsequently by treat and wash assay for extracts showing biologically significant results. The genotoxicity was determined in TK6 human lymphoblastoid cells using the in vitro micronucleus assay in micromethod. The results showed that all extracts analyzed induce no mutagenic activity. However, one of these extracts induced a biologically significant increase in the number of micronucleated cells. Our findings indicate the importance of the genetic damage detection for taking measures to suppress or reduce the exposure to harmful contaminants and encourage further research investigating genotoxic effects of industrially processed meat worldwide.

The effect of silver nanoparticles on the mutagenic and the genotoxic properties of the urban wastewater liquid sludges.

Nanoparticles are very effective compounds to transform and detoxicate common environmental contaminants. For this reason, crude urban liquid wastewater sludges were treated by silver nanoparticles (Ag-NPs, 100 nm) for 24 h. Both Ag-NPs' treated and untreated sludges were examined for the evaluation if there are possible mutagenic/anti-mutagenic, cytotoxic, and genotoxic/anti-genotoxic effects by Ames and Allium cepa tests. The results were then subjected to statistical analyses by using SPSS software and p < 0.05 was accepted as a significant value. The data obtained from the Ames test showed that while untreated crude liquid sludge had a significant mutagenic effect, Ag-NP-treated one decreased its mutagenicity. Similar effects were also observed in the chromosome aberration-Allium cepa tests. Significant chromosome aberrations observed were C-metaphase, sticky metaphase, sticky anaphase, anaphase bridge, vagrant chromosome, and multipolar anaphases. Both tests demonstrated that silver nanoparticle treatment decreased the major mutagenicity and genotoxicity detected in the liquid wastewater sludges.

Ames and random amplified polymorphic DNA tests for the validation of the mutagenic and/or genotoxic potential of the drinking water disinfection by-products chloroform and bromoform.

Chloroform and Bromoform are two abundant trihalomethanes found in Algerian drinking water. The investigation of the mutagenic hazard of these disinfection by-products was studied by Ames test as prokaryotic bioassay to show their mutagenic effects. For this, Salmonella typhimurium TA98 and TA100 strains were employed. Both chloroform and bromoform showed a direct mutagenic effect since the number of revertant colonies gradually increase in dose-dependent manner with all concentrations tested with the two bacterial strains and these were both in the absence and presence of S9 metabolic activation. The genotoxic hazard was also studied by random amplified polymorphic DNA test on the root cells of Allium cepa as eukaryotic bioassay. DNA extracted from the roots of the onion were incubated at different concentrations of chloroform and bromoform and then amplified by polymerase chain reaction. This was based on demonstrating a major effect of disappearance of bands compared to roots incubated in the negative control (distilled water). The results showed that these two compounds affected genomic DNA by breaks although by mutations.

Mutagenic and genotoxic effects of Guelma's urban wastewater, Algeria.

Assessment of water pollution and its effect upon river biotic communities and human health is indispensable to develop control and management strategies. In this study, the mutagenicity and genotoxicity of urban wastewater of the city of Guelma in Algeria were examined between April 2012 and April 2013. For this, two biological tests, namely Amesand chromosomal aberrations (CA) test in Allium cepa root tips were employed on the samples collected from five different sampling stages (S1-S5). In Ames test, two strains of Salmonella typhimurium TA98 and TA100 with or without metabolic activation (S9-mix) were used. All water samples were found to be mutagenic to S. typhimurium TA98 with or without S9-mix. A significant decrease in mitotic index (MI) was observed with a decrease in the percentage of cells in the prophase and an increase in the telophase. Main aberrations observed were anaphase bridges, disturbed anaphase-telophase cells, vagrants and stickiness in anaphase-telophase cells. All treatments of wastewater in April 2012, at S5 in July 2012, at S1 and S5 in November 2012, at S5 in February 2013, and at S1 in April 2013 induced CA when compared to the negative control. Some physicochemical parameters and heavy metals (Cd, Pb, and Cu) were also recorded in the samples examined.

Mutagenicity and genotoxicity of drinking water in Guelma region, Algeria.

In this study, a battery of genotoxicity assays for monitoring drinking water was performed to assess the quality of the water resulting from the treatment plants. Five different types of samples were collected: raw water (P1), treated after pre-chlorination (P2), treated after decantation (P3), treated post-chlorination (P4), and consumers' taps (P5-P12). This study aims to evaluate the formation/occurrence of mutagenic and/or genotoxic compounds in surface drinking waters treated with chlorine disinfectant, during four seasonal experiments: summer, autumn, winter, and spring between 2012 and 2013 by bacterial reverse mutation assay in both Salmonella typhimurium TA98 and TA100 strains with or without metabolic activation system (S9 mix) and Allium cepa root meristematic cells, respectively. All of water samples, except at P1, P2, and P5 in summer; P1 in autumn; and P1 and P3-P12 in spring without S9 mix, and at P1 and P2 in summer and P6 and P8-P12 in spring with S9 mix, were found to be mutagenic in S. typhimurium TA98. However, only P11 and P12 in winter were found to be mutagenic for TA100 without S9 mix. The tested preparations in Allium anaphase-telophase test revealed a significant decrease in mitotic index (MI) and a simultaneous increase in chromosome aberrations (CAs) compared to the control. The bridge, stickiness, vagrant chromosomes, and disturbed chromosome aberrations were observed in anaphase-telophase cells. Physicochemical analysis, trihalomethanes (THMs), romoform (CHBr3), chloroform (CHCl3), bromodichloromethane (CHBrCl2), and dibromochloromethane (CHBr2Cl) levels in water samples were also determined. The results show also that this short-term battery tests are applicable in the routine monitoring of drinking water quality before and after distribution.

Genotoxicity of drinking water disinfection by-products (bromoform and chloroform) by using both Allium anaphase-telophase and comet tests.

Genotoxic effects of bromoform and chloroform, disinfection by-products of the chlorination of drinking water, were examined by using mitotic index (MI), mitotic phase, chromosome aberrations (CAs) and comet assay on root meristematic cells of Allium cepa. Different concentrations of bromoform (25, 50, 75 and 100 µg/mL) and chloroform (25, 50, 100 and 200 µg/mL) were introduced to onion tuber roots. Distilled water was used as a negative control and methyl methansulfonate (MMS-10 µg/mL) as positive control. All obtained data were subjected to statistical analyses by using SPSS 15.0 for Windows software. For comparison purposes, Duncan multiple range tests by using one-way analysis of variance were employed and p < 0.05 was accepted as significant value. Exposure of both chemicals (except 25 µg/mL applications of bromoform) significantly decreased MI. Bromoform and chloroform (except 25 µg/mL applications) increased total CAs in Allium anaphase-telophase test. A significant increase in DNA damage was also observed at all concentrations of both bromoform and chloroform examined by comet assay. The damages were higher than that of positive control especially at 75-100 µg/mL for bromoform and 100-200 µg/mL for chloroform.