Assessment of human exposure to ochratoxin A (OT A) was achieved by
analysis of some foodstuff, food consumption from a series of individuals using the
duplicated diet method and urinary OTA concentration. Samples of foodstuffs
including cereals, legumes, dried fruits, dairy products and meats were collected
from Egyptian countryside, samples of duplicate diets and urine samples were
collected from 25 volunteers living in one area of the Egyptian village during one
month on a weekly basis. The method uses immunoaffinity column clean-up and
reversed phase high performance liquid chromatography (HPLC) with fluorescence
detector for quantification of the toxin. It was found that 33.57% of foodstuff samples
(a total 140 samples) contained OTA in variable quantities. All diet and urine
samples contained OT A. The exposure calculated from OT A levels in the diets were
below the tolerable daily intake recommended by JECFA at 1.2-14 ng Ikg bw/day ;
the average daily intake ranged from 1.07 to 8.43 ng/kg bw/day with a mean value
4.49±1.95. OTA urine levels ranged from 17-61ng/L with a mean value 31.40±11.15.
This suggests that the population is exposed to OTA at high frequency, since the
toxin is frequently found, albeit at low levels, in a number of commonly consumed
foods. High significant correlation were found between OTA consumption and
urinary OT A level suggesting that urine provide a good biomarker of intake. The effect
of garlic and ascorbic acid (fresh orange juice) on reducing OTA levels in human
was also investigated. The results indicate that garlic and orange juice effectively
reduced the levels of OTA in urine.