Percentage Of Polychromatic Erythrocytes Research Articles

Study Genotoxic and Cytotoxic effect of the fungicide Propamocarb- HCl in Albino mice

The study was designed to evaluate genotoxicity and cytotoxicity of the fungicide probamocarb- HCl using Swiss white mice Mus musculus .
 The evaluation of treatment effects with the dosage 1355 and 2349 mg/kg .bw of the fungicide was depended on genomarkers (Micronuclei in bone- marrow cells, evaluation of DNA damage in liver and bone-marrow cells using comet assay).
 The results showed significant linear increase at p≤0.05 between time of treatment and micronuclei which reached 420.40 ± 12.21 with replicate treatment of the dosage 1355 mg/kg.bw of the fungicide compared with 4.80 ± 2.10 for negative control and 592.60±5.83 with single dosage of 2493 mg/kg. bw of the fungicide. Change in the percentage of polychromatic erythrocytes also observed which have increased in linear manner with the increased time of treatment. It reached 11.23% with replicate treatment of the dosage 1355 mg/kg.bw of the fungicide and 10.62% with the single treatment of the dosage 2493 mg/kg.bw. compared with 9.71 for negative control. The number of micronucleated polychromatic erythrocytes was significantly increased in linear manner with the replicate treatment of the dosage 1355 mg/kg.bw of the fungicide which reached 310.60 ± 1.36 and 243.60 ± 5.29 with the single dosage of 2493 mg/kg.bw of the fungicide compared with 2.80 ± 1.06 for negative control.
 Treatment with Propamocarb-HCl induced damage in DNA of liver and bone-marrow cells. The value of OTM reached 58.40 ± 2.01 in bone-marrow cells with the single dosage of 2493 mg/kg.bw compared with 3.20 ± 0.66 for negative control. While it reached 61.80 ± 7.57 compared with 8.00 ± 1.38 for negative control in liver cells. The percentage of cells with damaged DNA reached 25.88% in bone-marrow and 30.62% in liver.

MELPHALAN-INDUCED CYTOTOXICITY IN THE BONE MARROW OF RATS BY FLOW CYTOMETRY MEASUREMENTS

Background. Bone marrow (BM) that contains hematopoietic cells of various lineages is a sensitive target for a number of cytotoxic agents including chemotherapy drugs.
 Objective. Flow cytometry (FCM) was chosen to test cytotoxicity in BM of rats, that received melphalan either intravenously (i.v.) or intraperitoneally (i.p.).
 Methods. One group of rats received melphalan i.v. (3 mg/kg) followed by the BM examination on the 3rd and 7th day after drug administration, whereas another group of animals received this drug i.p. in total doses of 9 and 15 mg/kg followed by the BM examination on the next day after the 3rd and 5th injection of the drug. BM cells were stained with acridine orange and analyzed by FCM. Cytotoxicity was assessed by determining the percentage of total nucleated cells (TNC%) among the whole BM cell population and by determining the percentage of polychromatic erythrocytes (PCE%) among the whole population of enucleated erythrocytes.
 Results. Regardless of the dose and regimen of melphalan administration, either i.v. or i.p. administered drug caused a significant reduction of TNC%. On the average, the i.p. administered drug resulted in about 2.0-fold decrease of TNC% (P<0.05), while the i.v. administered drug resulted in about 1.3-fold decrease of TNC% (P<0.05). As for enucleated erythrocytes, the i.p. administered drug resulted in about 1.4-fold decrease of PCE% (P<0.05), whereas the i.v. administered drug did not cause any changes in the PCE%.
 Conclusions. Under these experimental conditions, i.p. administrated melphalan is considerably more cytotoxic than i.v. administered melphalan. This cytotoxic effect is preferentially due to impaired erythropoiesis.

Safety evaluation of an oat grain alkaloid gramine by genotoxicity assays

Gramine is a natural indole alkaloid that has been isolated from different raw plants occurring mainly in Avena sativa, etc. The study was aimed to investigate the possible in vitro antioxidant, in vitro mutagenic, in vitro antimutagenic, and in vivo genotoxic activity of gramine using ferric reducing ability of plasma (FRAP) assay, Metal chelating, Ames bacterial reverse mutation test, and the mouse bone marrow micronucleus assay as well as chromosomal aberration. Four concentrations of gramine viz. 250, 500, 1000, and 2000 μg/mL were evaluated for its antioxidant activity in FRAP Assay and Metal Chelating Test. Four concentrations of gramine (1250 μg/plate, 2500 μg/plate, 5000 μg/plate, and 10 000 μg/plate) were employed in Salmonella typhimurium strains to study the mutagenicity in the presence and absence of standard mutagens, 2-aminofluorene (2-AF), sodium azide (SA), and 2-nitrofluorene (2-NF). Three doses, i.e. 0.1, 0.2, and 0.3 × the LD50 of gramine (i.e. 50 mg/kg, 100 mg/kg, and 150 mg/kg) were administered orally to either sex of Swiss albino mice for 48 h to study the genotoxic activity in micronucleus assay as well as chromosomal aberration. Gramine showed potent antioxidant activity in both the assay. Gramine at the given dose lacks mutagenicity as well as found to possess antimutagenic efficacy. Interestingly, S9 enzymes increase the antimutagenic activity in a dose-dependent manner. There was no significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCEs), as well as no significant difference in the percentage of chromosomal aberrations was observed between the gramine groups and the negative groups but percentage of polychromatic erythrocytes (PCEs) is found to be higher in all the gramine groups. These results indicate significant antioxidant, non-mutagenic as well as non-genotoxic activity of gramine in vitro and in vivo in the given doses.

Effect of blueberries (BB) on micronuclei induced by N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) and 7,12-dimethylbenz(a)anthracene (DMBA) in mammalian cells, assessed in in vitro and in vivo assays

The protective effect of blueberry (BB) on the clastogenic effects of MNNG and DMBA was evaluated with the induced micronucleus (MN) frequency as a biomarker, both in vitro and in vivo. Human hepatoma HepG2 cells, which contain most of the metabolic activating enzymes was used for the in vitro test. MN frequencies were determined in binucleated cells generated by blocking cytokinesis by use of cytochalasin-B. The MN frequency in vivo was determined in polychromatic erythrocytes (PCEs) from the bone marrow of treated mice. BB by itself was not toxic both in vivo and in vitro. There was no evidence of a potential physico-chemical interaction between BB and the test carcinogens in vitro. Pre-treatment with BB reduced the MN frequency induced by MNNG. But, simultaneous treatment and post-treatment with BB did not affect the frequency of MNNG-induced MN. BB did not affect the frequency of DMBA-induced MN in vitro under any test condition. Under in vivo conditions, BB reduced the frequencies of MNNG- and DMBA-induced MN in PCEs, but in the case of the protective effect of BB against DMBA a dramatic reduction in the percentage of PCEs was observed, suggesting increased cytotoxicity.

Avaliação in vivo da anticlastogenicidade de extratos de plantas medicinais do gênero Miconia através do teste do micronúcleo

The genus Miconia is comprised of approximately 1000 species. For some of them, biological activities have already been described such as the analgesic and the anti-microbial ones. The purpose of this work was to evaluate the possible protective and cytotoxic effects of the methanolic extract from M. albicans, M. cabucu, M. rubiginosa and M. stenostachya and the chloroformic extract from M. albicans in mice bone marrow cells in 540 mg/kg p.c. dose. The extracts were administered by means of forced feeding and the cyclophosphamide (CPA) was applied intraperitonially one hour after supplementation with extracts. All animals were submitted to euthanasia 30 hours after the treatment. The analyzed cells were extracted from mice bone marrow according to protocol described by Schmid (1975). The cytotoxicity of the extracts was evaluated through the percentage of polychromatic erythrocytes (PCE) in 200 erythrocytes (PCE + NCE). Two thousand PCEs of each animal were analyzed and the micronucleated polychromatic erythrocytes (MNPCEs) frequencies were scored. The results obtained indicated that none of the extracts associated with the CPA showed cytotoxic effect and only the extracts of M. rubiginosa and M. stenostachya showed protective effect to DNA. Chemical analyses of the extracts showed that the four species studied contain mainly flavonoids, phenolic compounds and tannins. The phytochemical characterization of these extracts could contribute to elucidate the protective effect presented only by the species M. rubiginosa and M. stenostachya , besides making it possible the study of other therapeutic activities.

Micronuclei induction by 13 week-inhalation of 1,1-dichloro-1-fluoroethane in Sprague-Dawley rats

To investigate the genotoxic effect of l,1-dichloro-1-fluoroethane (HCFC-141b), which was currently widely used as a cleaning solvent in the electronic parts industry and suggested as a potential reproductive effector, in vivo micronucleus tests were performed. Groups of 10 male and 10 female Sprague-Dawley rats were exposed, by inhalation (6 h/day, 5 days/week) to the vapors of HCFC-141b for 13 weeks using whole body exposure chambers at the concentrations of 0 (control), 1500, 3000, and 6000 ppm. The micronuclei frequencies among the polychromatic erythrocytes (PCEs) and the percentage of polychromatic erythrocytes among the total number of erythrocytes were counted in the bone marrow of rats, and body weights, organ weights, histopathology, clinical chemistry and hematologic changes were also observed. Statistically significant and dose-dependant increases were found in the micronuclei frequencies in the male rats ( P<0.01), yet not in the females. The decreases in the percentage of polychromatic erythrocytes among the total number of erythrocytes were also statistically significant ( P<0.05) in both sexes of the high concentration groups. However, no exposure-related effects of toxicological significance were noted with respect to organ weights, clinical chemistry and histopathology. Apart from it, only slightly decreased mean corpuscular hemoglobin concentration (MCHC) was noted in the females of 6000 ppm group ( P<0.05). These results suggest that HCFC 141b can induce the genetic effects, micronuclei in the rat bone marrows, especially in males, at earlier stages before the other general clinical and histopathologic changes occur if with more prolonged exposure.

In vivo andin vitro studies on the genotoxicity of cadmium chloride in mice

The genotoxic effect of cadmium chloride was evaluated in chromosomes of experimental mice using in vivo and in vitro studies. In vivo the induction of micronuclei, sister chromatid exchange in mouse bone marrow and chromosomal aberrations in both somatic and germ cells was investigated. Doses 1.9, 5.7 and 7.6 mg kg(-1) body wt. (single i.p. treatment) induced a significant and dose-dependent increase in the percentage of polychromatic erythrocytes with micronuclei. Such a percentage reached 2.1% with the highest tested dose, compared with 0.57% for the control (non-treated) and 2.2% for mitomycin c as the positive control. The dose of 1.9 mg kg(-1) body wt. had no significant effect with respect to sister chromatid exchange (SCE) but the doses of 5.7 and 7.6 mg kg(-1)body wt. increased the frequency of SCEs significantly. The frequency of SCE reached 7.35 +/- 0.26 per cell after treatment with the highest tested dose, which is a less than twofold increase compared with the control frequency of 4.6 +/- 0.42 per cell. However mitomycin c induced a much higher effect (12.1 +/- 0.73). Cadmium chloride also induced a significant increase in the percentage of chromosomal aberrations in mouse bone marrow at the doses of 5.7 and 9.5 mg kg(-1) body wt. (single i.p. treatment). The effect is a function of cadmium chloride concentration. Moreover, cadmium chloride induced its maximum effect concerning the induction of chromosomal aberrations in mouse bone marrow cells 24 h after treatment, compared with 12 and 48 h. In germ cells, chromosomal aberrations were observed in mouse spermatocytes 12 days post-treatment with the dose of 5.7 mg kg(-1) body wt. Moreover, a pronounced reduction in the number of spermatocytes was observed after administration of cadmium chloride (0.9, 1.9 and 5.7 mg kg(-1) body wt.) In in vitro studies, the three tested concentrations of 10, 15 and 20 microgram ml(-1) cadmium chloride induced a statistically significant increase in the frequency of SCEs in cultured mouse spleen cells. The concentrations of 15 and 20 microgram ml(-1) also induced chromosomal aberrations in mouse spleen culture. The ability of vitamin C (l-ascorbic acid) to minimize the incidence of chromosomal aberrations induced by cadmium chloride in cultured mouse spleen cells was investigated. Vitamin C at the concentrations of 3 and 6 microgram ml(-1) significantly minimized the percentage of aberrant cells induced by cadmium chloride.

Frequency of micronuclei in the blood and bone marrow cells of mice exposed to ultra-wideband electromagnetic radiation

Purpose: To investigate the extent of genetic damage in the peripheral blood and bone marrow cells of mice exposed to ultra-wideband electromagnetic radiation (UWBR). Materials and methods: CF-1 male mice were exposed to UWBR for 15min at an estimated whole-body average specific absorption rate of 37mWkg-1. Groups of untreated control and positive control mice injected with mitomycin C were also included in the study. After various treatments, half of the mice were killed at 18h, and the other half at 24h. Peripheral blood and bone marrow smears were examined to determine the extent of genotoxicity, as assessed by the presence of micronuclei (MN) in polychromatic erythrocytes (PCE). Results: The percentages of PCE and the incidence of MN per 2000 PCE in both tissues in mice killed at 18h were similar to the frequencies observed in mice terminated at 24h. There were no significant di erences in the percentage of PCE between control and the mice with or without UWBR exposure; the group mean values (standard deviation) were in the range of 3.1 0.14 to 3.2 0.23 in peripheral blood, and 49.0 3.56 to 52.3 4.02 in bone marrow. The mean incidence of MN per 2000 PCE in control and in mice with or without UWBR exposure ranged from 7.7 2.00 to 9.7 2.54 in peripheral blood and 7.4 2.32 to 10.0 3.27 in bone marrow. Pairwise comparison of the data did not reveal statistically significant di erences between the control and mice with or without UWBR exposure groups (excluding positive controls). Conclusion: Under the experimental conditions tested, there was no evidence for excess genotoxicity in peripheral blood or bone marrow cells of mice exposed to UWBR.

In vitro and in vivo studies demonstrate non-mutagenicity of the herbicide metolachlor

The herbicide metolachlor was evaluated for genotoxic potential. Metolachlor did not induce micronuclei in mice, however at 40 mg/kg it significantly decreased the percentage of polychromatic erythrocytes, which is a cytotoxic effect. Metolachlor did not induce chromosomal aberrations in human lymphocytes in vitro, but 2.0 mug/ml culture medium resulted in cytotoxicity, decreasing the mitotic index significantly. The indirect exposure test was carried out by adding plasma from metolachlor-pretreated rats to the human lymphocyte cultures. There was no indication of clastogenicity by metolachlor metabolites. On the other hand, plasma of cyclophosphamide-pretreated rats had a significant clastogenic effect

Mutagenicity of 2-bromopropane.

2-Bromopropane (2BP, isopropyl bromide), a substitute for freon, has recently been suspected to be the causative chemical for the outbreak of some reproductive dysfunctions such as amenorrhea and oligospermia in workers who has been exposed to this solvent in an electronic factory. Bacterial mutation assays, chromosome aberration analysis in vitro, and micronucleus tests in vivo, were carried out to clarify the mutagenicity of 2BP. 2BP induced mutagenicity in Salmonella typhimurium TA100 with metabolic activation in a dose-dependant manner. 2BP induced mutagenicity in TA1535 as well, with or without metabolic activation. These observations indicated that 2BP induced the base-pair substitution type mutations in Salmonella strains. The chromosome aberration analysis showed negative results in Chinese hamster lung cells treated with different concentrations, ranging from 0.077 to 2.46 mg/ml for 6 h with metabolic activation and for 24 h without metabolic activation. The micronucleus frequencies were recorded by examining polychromatic erythrocytes in the bone marrows of rats which were intraperitoneally injected with 2BP for 28 days. There was no significant increase in the micronucleus frequencies at any of the different doses of 2BP (125 mg/ kg b.w./day, 250 mg/kg b.w./day, and 500 mg/kg b.w./day). However, in comparison to controls, there was a significant decrease in the percentage of polychromatic erythrocytes in the total number of erythrocytes. This suggests that there may be bone marrow depression in hematopoiesis at these dose levels of 2BP. Despite the dose levels which showed hematopoietic inhibition in the bone marrow, no micronucleus formation was induced.

Cytogenetic effects in mice of divinylbenzene-55 inhalation

Male B6C3F1 mice (8 weeks of age) were exposed by inhalation to divinylbenzene-55 (DVB-55), at target concentrations of 0, 25, 50 and 75 ppm for 6 h per day for 3 days. Following exposure the animals were killed, blood smears were prepared for micronucleus (MN) analysis, and the spleens were removed and cultured for sister chromatid exchange (SCE) and chromosome aberration (CA) analyses. DVB-55 induced a dose-dependent increase in SCE with the two highest doses reaching statistical significance. Similarly, there was a statistically significant although less pronounced increase in the frequency of CAs in splenocytes and MN in polychromatic erythrocytes. There was no indication of toxicity as measured by cell cycle kinetics in the splenocytes or the percentage of polychromatic erythrocytes in the peripheral blood smears. Thus, DVB-55 appears to be a weak genotoxicant in vivo.

Toxicological potential of malathion residues in stored soybean seeds

Succinate-14C-malathion penetrates readily into soybean seeds. The total internal residues inside the seeds amounted to 58-65% of the applied dose after 30 weeks, of which 8-9% were in the form of bound residues. The major part of the internal methanol extractables are chloroform soluble metabolites which include malathion (about 60%), monocarboxylic acid (15%) and its decarboxylation product (8%). The water soluble metabolites contained only one radioactive substance, namely malathion dicarboxylic acid. The toxicological potential of the total internal residues was studied by feeding mice with the washed seeds for about 2.5 months. Treated mice suffered from deterioration of hepatic and renal function as indicated by the observed increased level of blood serum esterases and blood urea nitrogen. The results of blood biochemistry are supported by the histopathological changes observed in the liver, kidney, stomach and intestine. The organs showed degenerative changes including leucocytic aggregation, congestion and dilatation of blood vessels. Other adverse effects caused by malathion residues are indicated from cytogenetic studies on bone marrow of treated mice. Studies showed an initial bone marrow toxicity as indicated by increase in percentage of polychromatic erythrocytes over controls. This effect diminished upon prolongation of feeding period over one month. Feeding with malathion residues affected a gradual increase, with feeding period, in the percentage of polychromatic erythrocytes with micronuclei, a parameter recommended for detecting chemical mutagenes in animal test systems.

Increase in micronucleated erythrocytes associated with babesiosis in Syrian golden hamsters

The effect of infection by Babesia microti, a tick-borne piroplasm endemic to the northeastern United States, on the temporal pattern of micronucleated erythrocyte frequencies in peripheral blood was investigated in male Syrian golden hamsters. Significantly greater frequencies of micronucleated erythrocytes occurred in the blood of infected hamsters from 26 to 46 days after injection with B. microti, the magnitude of which within individual hamsters correlated highly with the percentage of polychromatic erythrocytes and the extent of parasitization. These data suggest that parasitic infection and other factors which alter the rate of erythropoiesis should be considered when the micronucleus assay is used in environmental or laboratory studies of genetic toxicity.

The effect of exposure regimen and duration on benzene-induced bone-marrow damage in mice: I. Sex comparison in DBA/2 mice

In the mouse, the concurrent evaluation of micronuclei frequencies in peripheral blood polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) permits an assessment of both recently-induced and chronically-accumulated bone-marrow damage. This assay system was used to evaluate on a weekly basis the effect of exposure duration (1–13 weeks, 6 h per day) and exposure regimen (Regimen 1:5 exposure days per week; Regimen 2:3 exposure days per week) on the ability of 300 ppm benzene to induce genotoxic damage in the bone marrow of male and female DBA/2 mice. In addition, an analysis of the percentage of PCE in peripheral blood was used to evaluate benzene-induced alterations in the rate of erythropoiesis. Exposure to benzene induced a marked increased in the frequency of micronucleated PCE (MN-PCE), an effect which was considerably greater in male mice than in female mice. In both sexes, the induction of MN-PCE was independent of exposure regiment and of exposure duration. Exposure to benzene also resulted in an exposure duration-dependent increase in the frequency of MN-PCE. The frequency of MN-NCE increased more slowly in female than in male mice and, within each sex, more slowly in Regimen 2 animals. Apparent steady-state conditions for MN-NCE frequencies were attained by about the fifth week of exposure in female mice exposed by either regimen and in male exposed by Regimen 2. Steady-state conditions for MN-NCE frequencies in male mice exposed to benzene by Regimen 1 did not occur during the duration of the study. An analysis of %PCE data revealed an initial severe depression in the rate of erythropoiesis in both sexes, with the return in the production of PCE to control levels being dependent on both sex and exposure regimen. Suppression of PCE production occurred throughout the course of the study in Regimen 2 males, while the percentage of PCE returned to control levels sporadically after 5 weeks in Regimen 1 males and within 5 weeks in females, regardless of regimen. Thus, while the sex-dependent induction of genotoxic damage by multiple exposures to benzene over a 13-week period was independent of exposure regimen and duration, the induction of cytotoxic damage was both sex- and regimen-dependent. The most severe depression of erythropoiesis occurred in male DBA/2 mice exposed to benzene by the more intermittent regimen (i.e., 3 days/week versus 5 days/week). The results of this study underscores the complexity of the peripheral blood micronucleus assay and emphasizes the utility of evaluating micronucleated PCE and micronucleated NCE frequencies and the percentage of PCE in the same animals across time in multiple exposure situations.

Cytogenetic effects of the insecticide methamidophos in mouse bone marrow and cultured mouse spleen cells.

The cytogenetic effect of the insecticide methamidophos (0,S-dimethylphosphoroamidothiolate) was studied in mouse bone marrow and mouse spleen cells in culture. In vivo the ability of methamidophos to induce micronuclei and sisterchromatid exchange in mouse bone marrow was investigated. In vitro mouse spleen cells in culture were used to assess the ability of the insecticide to induce chromosomal aberrations and sister chromatid exchange. Three different routes of application for the pure insecticide were tested so as to cover the different possibilities for human exposure to the insecticide. Intraperitoneal, oral and dermal treatment with methamidophos caused toxicity to marrow as indicated by a significant increase in the percentage of polychromatic erythrocytes (PEs) over that of the control. Methamidophos showed mutagenic potential as evidenced by a positive response in the micronucleus and chromosomal aberrations assays. Thus, single and multiple i.p. injections at 6 and 4.5 mg methamidophos/kg body wt., oral administration of the insecticide for 14 consecutive days at a dietary level of 100 ppm and multiple dermal treatments (total 4) with 24 mg/kg body wt. induced a statistically significant increase in the frequency of PEs with micronuclei in mouse bone marrow. Moreover, the tested concentrations of methamidophos as low as 0.25 microgram/ml induced a high percentage of metaphases with chromosomal aberrations in cultured mouse spleen cells. Methamidophos is a weak inducer of SCEs in mouse bone marrow and cultured mouse spleen cells.

Cytogenetic effects of pesticides: III. Induction of micronuclei in mouse bone marrow by the insecticides cypermethrin and rotenone

The production of micronuclei in mouse bone marrow by the pyrethroid insecticide, cypermethrin and the botanical insecticide, rotenone was examined. Three routes of administration were used for the insecticides: intraperitoneal, oral and dermal. The different routes of treatment with cypermethrin and rotenone caused toxicity of marrow as indicated by a significant increase in the percentage of polychromatic erythrocytes (PEs) over that of the control. Cypermethrin showed mutagenic potential as evidenced by a positive response in the micronucleus assay. Oral administration of the insecticide at a dietary level of 900 ppm for 7 and 14 consecutive days as well as double and multiple (total 4) dermal treatments (360 mg/kg body wt.) induced a statistically significant increase in the frequency of PEs with micronuclei. The conducted intraperitoneal (i.p.) treatments with cypermethrin: single injection at 60 and 180 mg/kg body wt., double and multiple injections (total 3) at 60 mg/kg body wt. did not affect the percentage of PEs with micronuclei. The different treatments with rotenone: single, double and multiple (i.p.) injections (total 3) at 2 and 3 mg/kg body wt., oral administration for 14 consecutive days at dietary level of 225 ppm and multiple dermal treatments (total 4) with 135 mg/kg body wt. showed no effect on the frequency of micronuclei in PEs.

Iodine-125 induced micronuclei and sperm head abnormalities in mice.

Swiss albino mice were injected with 0 (controls) 5, 10 or 15 microCi of iodine-125 (125I) and a high incidence of micronuclei in young bone marrow erythrocytes and of sperm head abnormalities was observed. The percentage of polychromatic erythrocytes containing micronuclei in mice treated with 0, 2.5, 5 and 7.5 microCi of 125I administered twice (at 30 and 6 h before sampling) was 0.23, 0.44, 0.56 and 0.72, respectively. The percentage (mean) of abnormal sperm recorded in controls during 1-3, 4-5 and 6-8 weeks was 3.3, 3.7 and 3.7 respectively, whereas the values for the same periods in the 5 microCi (5.5, 6.4 and 7.3), 10 microCi (7.7, 8.4 and 10.0) and 15 microCi (10.3, 9.9 and 10.2) groups were significantly higher. These results suggest that 125I can induce genetic damage in both somatic and germ cells.

Testing natural indigo for genotoxicity

The genotoxicity of indigo has been assessed by two short-term tests. The mutagenicity of natural indigo was compared with that of synthetic indigo. Both chemicals were tested using the standard procedure of the Salmonella/microsome mutagenicity test as described by Ames. The substance exhibits mutagenicity towards strains TA1538 and TA98 when S9 preparations of rat liver induced with Aroclor 1254 were present in the medium. The clastogenic potential was evaluated by the micronucleus test in the bone marrow of male mice. The test compound was administered twice with an interval of 24 h, the animals were killed 30 h and 54 h after the first treatment. When the test compound was given by oral gavage as two equal dosages of 0.1, 1 and 1.2 g/kg body weight, no statistically significant increase in the percentage of polychromatic erythrocytes with micronuclei was observed for any group treated with natural indigo.

Cytogenetic effects of pesticides: II. Induction of micronuclei in mouse bone marrow by the insecticide gardona

The induction of micronuclei in mouse bone marrow by the organophosphorus insecticide gardona (also known as tetrachlorvinphos) was tested. 3 routes of administration were used for the pure insecticide: intraperitoneal, oral and dermal. The different routes of treatment with gardona caused toxicity of marrow indicated as significant increases in the percentage of polychromatic erythrocytes over that of the control. Intraperitoneal and oral treatments induced a statistically significant percentage of micronucleated PE.