Cytotoxicity of the Murine Keratinocyte Line HEL30 Exposed to the JP-8 Jet Fuel Components M-xylene 1-Methylnaphthalene and N-nonane
Abstract
In vitro models are being used to evaluate the toxic and irritating effects of JP-8, a kerosene-based jet fuel. JP-8 components are volatile, which makes in vitro studies difficult to evaluate dose-response relationships due to changes in chemical dosimetry caused by evaporation from the exposure medium. An in vitro approach testing volatile chemical toxicity that we have recently developed was used to evaluate the toxicity of the JP-8 components m-xylene, 1-methylnaphthalene (1-MN), and n-nonane in keratinocytes. Partition coefficients were measured and used to estimate the chemical concentration in the keratinocytes. The EC50 for m-xylene and 1-MN decreased significantly (P<0.05) at 1 2, and 4 hi. For n nonane, no significant decreases in the EC50 values were observed over time; marginal cytotoxicity of n nonane in keratinocytes was observed at 1 hi. Within 4 hi, about 75-90% of each volatile chemical was observed to be lost from the exposure medium when tissues were exposed in unsealed 24-well plates. This decrease resulted in significantly higher medium chemical concentrations needed to obtain EC50 values when compared to tissues exposed in sealed%vials. This study demonstrates that chemical evaporation during in vitro exposures can significantly affect toxicological endpoint measurements. Ultimately, relating target cell chemical concentration to cellular responses in vitro could be used in determining an equivalent external dose using a biologically-based mathematical model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2002
- Accession Number
- ADA424203
Entities
People
- Dan L. Pollard
- Gary L. Siegel
- James N. Mcdougal
- James V. Rogers