Mutation of human cells by kerosene soot

Area of Science:

• Environmental Health
• Toxicology
• Molecular Biology

Background:

• Polycyclic aromatic hydrocarbons (PAHs) in complex mixtures like kerosene soot are potential mutagens.
• Metabolic activation by enzymes is often required for compounds to become genotoxic.
• Previous studies have used bacterial assays to assess mutagenicity.

Purpose of the Study:

• To investigate the mutagenic potential of kerosene soot and its components in human cells.
• To establish a human cell-based assay for detecting mutagens that require metabolic activation.
• To compare the mutagenicity of kerosene soot with bacterial assay results.

Main Methods:

• Human diploid lymphoblasts were used in a forward mutation assay at the hypoxanthine-guanine phosphoribosyltransferase (hprt) locus.
• Coincubation with Sprague-Dawley rat liver postmitochondrial supernatant provided metabolic activation (mixed-function oxygenase activity).
• Kerosene soot extract, benzo[a]pyrene (BP), and cyclopenta[cd]pyrene (CP) were tested.

Main Results:

• The polycyclic aromatic hydrocarbon fraction of kerosene soot induced forward mutations in human lymphoblasts.
• Benzo[a]pyrene (BP) was mutagenic at higher concentrations, while cyclopenta[cd]pyrene (CP) contributed approximately 8% to the observed mutations.
• The human lymphoblast assay successfully detected mutagenicity of compounds requiring metabolic activation.

Conclusions:

• The developed human lymphoblast assay is effective for evaluating the mutagenicity of complex mixtures.
• Cyclopenta[cd]pyrene is a significant mutagenic component within kerosene soot.
• This assay provides a valuable tool for assessing the genotoxic risk of environmental pollutants.