Levels of ochratoxin A in serum from urban and rural Portuguese populations and estimation of exposure degree

Urban and rural population exposure to ochratoxin A (OTA) in central zone of Portugal was investigated in three places: Coimbra, Verride and Ereira. alytical method proposed for the determination of ochratoxin A involved extraction with chloroform-orthophosphoric acid, cleanup through an immunoaffinity column (IAC), high performance liquid chromatography (HPLC) with spectrofluorimetric detection (FD) for separation and identification of ochratoxin A, and confirmation with HPLC–FD after OTA methylation in serum. The limit of quantification of the proposed method was 0.1 μg/L for serum and 0.05 μg/L for blood. OTA recoveries in serum ranged from 70.3% to 115.3% for levels at 0.25 μg/L and 0.5 μg/L, respectively, with a within-day RSD between 8.0% and 16.2%. oxin A serum levels were evaluated in an hundred and four donors from Coimbra city, Verride, and Ereira. The study revealed a frequency of detection of 100%. The ratio of ochratoxin A level in serum to whole blood was 2.0 ± 0.7. erall concentrations range from 0.25 to 2.49 μg/L, 0.14 to 1.91 μg/L, and 0.19 to 0.96 μg/L, for samples of Verride, Ereira, and Coimbra, respectively. The mean concentration and standard deviation were 0.78 ± 0.53 μg/L, 0.44 ± 0.31 μg/L, and 0.42 ± 0.18 μg/L for the same samples. A significant difference was found in Verride population (P-value = 0.000). of OTA are clearly higher in males from rural areas than in females. For all samples, a significant difference was found in Verride male population (P-value = 0.014).