Safety assessment for genetically modified sweet pepper and tomato.

The coat protein (CP) gene of cucumber mosaic virus (CMV) was cloned from a Chinese CMV isolate, the CaMV promoter and NOS terminator added and the gene construct was transformed into both sweet pepper and tomato plants to confer resistance to CMV. Safety assessments of these genetically modified (GM) plants were conducted. It was found that these two GM products showed no genotoxicity either in vitro or in vivo by the micronucleus test, sperm aberration test and Ames test. Animal feeding studies showed no significant differences in growth, body weight gain, food consumption, hematology, blood biochemical indices, organ weights and histopathology between rats or mice of either sex fed with either GM sweet pepper or tomato diets compared with those with non-GM diets. These results demonstrate that the CMV-resistant sweet pepper and tomato are comparable to the non-GM counterparts in terms of food safety.

[Study on hereditary toxicity of bass wood dust].

OBJECTIVE: To explore the genotoxicity of bass wood dust. METHODS: Micronucleus frequency in peripheral lymphocytes of workers exposed to bass wood dust in a match factory were examined, solution of bass wood dust emmersion was prepared and the effect on micronucleus frequency in poly-dyeing red blood cell of mice's sternum marrow was also detected. Single cell gel electrophoresis assay was used to detect DNA damage in liver cell, the level of oxygen free radical, lipid peroxidation(MDA) in the liver and the activity of superoxide dismutase(SOD) in red blood cells were also studied. RESULTS: The positive frequency of micronucleus in bass wood-exposed workers with different length of service (0-, 5-, > or = 10 a) were 50.0%, 51.9%, 50.0% respectively, significantly higher (P < 0.01) than that of the control group(4.5%). A dose-effect relationship could also be found in the mice's micronucleus frequency study(r = 0.78, P < 0.01). The activities of SOD[(10.98 +/- 5.74), (15.70 +/- 7.54), (29.63 +/- 14.97) microgram/g Hb] were significantly lower than that of control group[(35.80 +/- 12.92) microgram/g Hb], and the level of MDA[(4.93 +/- 0.90), (4.61 +/- 1.06), (4.33 +/- 0.69) mmol/g liver] were significantly higher than that of the control group[(2.51 +/- 0.34) mmol/g liver]. Single cell gel electrophoresis study showed DNA strand breaks increased with the dose increase and the level of oxygen free radical also increased with the dose increase. CONCLUSION: Bass wood dust may have certain degree of genotoxicity.