Enhanced clastogenicity of contaminated groundwater following UV irradiation detected by the Tradescantia micronucleus assay.
The Tradescantia micronucleus (Trad-MCN) assay was used to determine clastogenic effects of contaminated groundwater collected near a hazardous waste landfill. Water samples were taken from a purification plant (activated charcoal filtration, UV irradiation) which was built to avoid groundwater contamination by this landfill. Five series of experiments were conducted during approximately 4 months. In addition, water samples were irradiated under laboratory conditions with increasing doses of UV light. Several field water samples gave positive, dose-dependent effects before filtration and irradiation. Maximal values (6.1 +/- 4.7 micronuclei (MCN)/100 tetrads) were six-fold above controls. UV irradiation of activated charcoal-filtered water resulted in an enhancement of MCN frequencies. Exposure of groundwater to UV irradiation in the laboratory led to a dose-dependent increase of micronuclei. At the highest dose (1500 J/m2) the MCN frequency was more than six times higher than in the unirradiated sample (5.4 +/- 1.0 vs. 0.8 +/- 0.4 MCN/100 tetrads). The clastogenicity of UV-irradiated samples decreased with a half-life of approximately 1 day. Irradiation of tap water did not increase the MCN frequency. Our results indicate that irradiation of water with UV light for disinfection purposes might lead to a transiently increased genotoxicity of chemically polluted water samples.
Helma
C
C
Institute for Tumor Biology-Cancer Research, Vienna, Austria.
Sommer
R
R
Schulte-Hermann
R
R
Knasmüller
S
S
D006846:Hydrocarbons, Halogenated / Q000528:radiation effects* / Q000633:toxicity; D007220:Industrial Waste / Q000009:adverse effects; D015162:Micronucleus Tests / Q000379:methods; D009153:Mutagens / Q000633:toxicity*; D010944:Plants / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D012989:Soil Pollutants / Q000009:adverse effects; D012990:Soil Pollutants, Radioactive / Q000009:adverse effects; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014877:Water Pollution, Chemical / Q000009:adverse effects*; D014878:Water Pollution, Radioactive / Q000009:adverse effects*
D006846:Hydrocarbons, Halogenated; D007220:Industrial Waste; D009153:Mutagens; D012989:Soil Pollutants; D012990:Soil Pollutants, Radioactive