Reference values of urinary 3,5,6-trichloro-2-pyridinol in the Italian population - Validation of analytical method and preliminary results (Multicentric study)

The interlaboratory validation of analytical procedures for the assay of ur inary 3,5,6-trichloro-2-pyridinol (TCP) in the general Italian population i s reported. The determinations were performed by high-resolution gas chroma tography (HRGS) with electron capture detection and HRGS with mass spectrom etry (MS) in 2 laboratories. The urine samples were from 42 participants fr om 3 regions of Italy. The results were evaluated by interlaboratory qualit y control. Urinary TCP concentrations were above the detection limit (1.2 m u g/L) in 88% of the population, with a mean detectable concentration [QM ( GSD)] of 2.8 (1.9) mu g/g creatinine (creat). (GM, geometric mean; GSD, geo metric standard deviation.) The Mann-Whitney U test showed that wine consum ption was a statistically significant variable (p < 0.05) for urinary conce ntrations of TCP. Analysis of variance of the logarithm of urinary TCP vers us wine consumption and diet showed a statistically significant fit. The mo del used explained 30% of the total variance: wine consumption and diet acc ounted for 37 and 17% respectively of the explained variance.