Are We Misreporting Toxaphene?

Oral Presentation

Prepared by J. McAteer1, D. Gaynor2
1 - QA/QC Solutions, LLC, 7532 Champion Hill Rd. SE, Salem, OR, 97306, United States
2 - Phoenix Chemistry Services, 126 Covered Bridge Rd., N. Ferrisburgh, VT, 05473, United States


Contact Information: [email protected]; 503-763-6948


ABSTRACT

Technical toxaphene is a complex mixture of hundreds of chlorinated organic compounds. In environment compartments, this mixture is subject to microbial and non-microbial degradation resulting in weathered toxaphene. For example, toxaphene has a demonstrated half-life ranging from weeks to about 14 years; today, more than 87.5% of the original mixture could be transformed into degradation products. For this reason, analysis for technical toxaphene using routine analytical methods (e.g., Method 8081 by GC/ECD is not sufficient because unweathered toxaphene and a select number of congeners are used qualitatively and quantitatively. Even an experienced analyst, who has observed this transformation over time, and who may be able to identify weathered toxaphene, cannot sufficiently offer data users effective interpretation of their results. Appropriate reference standard(s) need to be developed and the use of other analytical methods (e.g., GCxGC-TOFMS) may be needed to better characterize and quantify weathered toxaphene.

As quality assurance specialists, it is our responsibility to help the regulated community plan for efficient and useful testing regimens; guide regulators to the best science and data to make good decisions; support analytical innovation in the commercial and research communities; and work with all groups to ensure that risk factors are established that are applicable and accurate. Our response needs to be dynamic with sufficient flexibility to provide the tools for quantitative measurements and usable interpretation. Developing a more representative analytical method and appropriate reference standard for weathered toxaphene, as well as other complex contaminants undergoing transformation, presents a challenge and an opportunity to explore a new paradigm in environmental testing and regulation. We must be ready to change our response as the chemicals themselves change. This presentation will discuss the concerns regarding the analysis of weathered toxaphene, its implications, and possible solutions.