Screening methodology for coal-derived organic contaminants in water

Abstract

A screening methodology designed to detect the presence of organic materials that leach into water from coal deposits was developed and evaluated. Analytical objectives included the ability to detect 16 polynuclear aromatic hydrocarbons (PAHs) at the lowest practical levels, capability for fingerprint analysis of other compounds, and ease of use under remote field conditions. The approach developed involved drawing 1 L water samples through a styrene divinylbenzene-based solid-phase extraction cartridge by suction, elution of the cartridge with tetrahydrofuran/hexane, evaporative concentration of the eluent, and reconstitution in acetonitrile, followed by analysis using high-pressure liquid chromatography with ultraviolet absorption and fluorescence detectors. The method was found to be easy to use under field conditions, providing generally acceptable recoveries and, in most cases, lower detection limits than current regulatory methods. The ability to detect PAHs and other organic compounds in simulated coal leachate solutions was demonstrated.

Keywords:

• Polynuclear aromatic hydrocarbons (PAHs)
• Coal
• Leachate
• Water analysis
• High-pressure liquid chromatography (HPLC)
• Solid-phase extraction (SPE)
• Hydrophobic organic contaminants (HOC)

Acknowledgments

This study was supported in part by grant 5D43 TW00641-03 from the Fogarty International Center, National Institutes of Health, USA, and grant SfP 971905 from NATO. The assistance of Dr. Paul R. Loconto with development of the laboratory analysis is sincerely appreciated.