Bioavailability of Manufactured Gas Plant Residue (MGP) Components in Mice Following Ingestion: Comparison of Adulterated Powder and Gel Diets

Abstract

The effect of a diet matrix (gel or powder) on the urinary excretion of 1-hydroxypyrene and hydrocarbon binding to DNA was investigated in mice following the ingestion of manufactured gas plant residue (MGP). Two MGP mixtures that varied in chemical composition were evaluated. Female B6C3F₁ mice were maintained for 15 days on a basal gel or powder diet containing 0.1% and 0.3% of either MGP sample. Urine was collected on the first, seventh, and fourteenth day of diet administration. 1-Hydroxypyrene levels in urine were determined using HPLC and fluorescence. Animals were sacrificed on the fifteenth day and lung and forestomach were excised and DNA isolated. Chemical-DNA adduct formation was evaluated using ³²P-postlabeling and multidimensional PEI-cellulose TLC. The extent of 1-hydroxypyrene excretion in urine and the levels of DNA adducts detected in tissues indicated that diet matrix has little effect on the bioavailability of MGP chemical components when ingested by mice.

Key Words:

• PAH
• MGP
• 1-hydroxypyrene
• DNA adduct
• ³²P-postlabeling