کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4411059 | 1307577 | 2011 | 6 صفحه PDF | دانلود رایگان |
One of the major challenges for mutagenicity assessment of environmental samples and individual compounds for example in the Ames fluctuation test (AFT) is the establishment and control of a well defined exposure concentration. Thus, a combination of passive dosing with silicone O-rings (SRs) together with an analytical confirmation of the freely dissolved concentration (FDC) is presented. FDCs are often determined with a combination of solid phase micro-extraction (SPME) with gas chromatography (GC). For compounds with poor performance in GC, a high performance liquid chromatography–mass spectrometry (HPLC–MS) analysis of bi-distilled water dosed with identically loaded SRs is suggested to avoid interference of the bacterial culture. The approach was tested for six amino-, nitro-, and keto-substituted polycyclic aromatic compounds with a log KOW range of 2.5–5.1 without metabolic activation. The method provided reliable concentration-effect relationships and freely dissolved 50% effect concentrations (DEC50) 3–33 times lower than nominal effect concentrations (NEC50) derived in parallel solvent-dosed AFT. Partition coefficients and NEC50/DEC50 ratios were well correlated with lipophilicity.
Research highlights
► Passive dosing for AFT with silicon rings for amino- and nitropyrenes.
► Combination with concentration confirmation of thermolabile compounds using LC–MS.
► Nominal effect concentrations may underestimate hazards by a factor of more than 30.
► Partition coefficients and dissolved effect concentrations estimated using log KOW.
Journal: Chemosphere - Volume 83, Issue 4, April 2011, Pages 409–414