Assessment of Fumonisin B1 in pig hair as an exposure biomarker.

Fumonisin B1 (FB1) is a common contaminant of corn (Zea mays L.) that causes pulmonary edema in pig with high mortality. Clay products have been used as absorbent of FB1 to reduce its effects. FB1 contamination in pig is difficult to detect and swine hair may be used as a non-invasive biomarker for the presence of this toxin. The aim of this study was to evaluate the presence of fuminisin B1 in swine hair in swine groups exposed to FB1 with clay. Male swine were fed with standard laboratory chow, tap water and housed indoors under controlled conditions for 21 days. They were divided in four groups of 8 pigs: control (Group A), 15 mg of fungal culture kg-1 (Group B), 15 mg of fungal culture kg-1 and 0.15% of experimental clay (Group C), 15 mg of fungal culture kg-1 and 0.20% of experimental clay (Group D) and evaluated in the 3rd and 6th weeks. Hair samples were stirred in ethanol for 15 minutes and dried at 50 oC for 3 hours, cut into small pieces. 0.5 g of swine hair samples were extracted with 20 mL of methanol overnight at 50 oC. The extract was filtered, and 15 mL was dried, resuspended in 20 mL of methanol: water (70:30), added 8 mL of water and filtered again. The solution was washed with 5 mL of hexane, centrifuged at 3000 rpm and top layer was discarded. pH was adjusted to 6. An aliquot of 20 mL of the extract was passed through the SAX column and eluted with 14 mL of methanol: acetic acid (0.5%). The eluted was dried, resuspended in 300 μL of water: acetonitrile (90:10), centrifuged and injected in HPLC. On the 3rd week, fumonisin B1 was detected in levels of 20.9, 11.4 and 18.5 ng.g-1 on group B, C and D, respectively. On the 6th week, toxin was identified only on group B at a level of 1.3 ng.g-1 and in the both weeks, it was not possible to identify FB1 on the control samples. Swine hair can accumulate FB1, however clay showed an interference in the toxin absorption, decreasing it. [ABSTRACT FROM AUTHOR]