EPA Science Inventory

Persistent Organochlorine Pesticides and their Metabolites in Alligator Livers from Lakes Apopka and Woodruff, Florida, USA

Citation:

GARRISON, A. W., L. J. Guillette, T. E. Wiese, AND J. K. AVANTS. Persistent Organochlorine Pesticides and their Metabolites in Alligator Livers from Lakes Apopka and Woodruff, Florida, USA. INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY. Taylor & Francis, Inc., Philadelphia, PA, 90(2):159-170, (2010).

Description:

Reproductive disorders in American alligators (Alligator mississippiensis) inhabiting Lake Apopka, Florida, have been observed for several years. Such disorders are hypothesized to be caused by endocrine disrupting contaminants occurring in the Lake due to pesticide spills and runoff from bordering agricultural lands. Various studies have resulted in identification of several persistent organic pollutants (POPs), some of them known endocrine disrupters, in various alligator tissues and fluids. In this report, livers from 12 juvenile alligators inhabiting Lake Apopka were extracted and analyzed using gas chromatography-mass spectrometry with chiral GC columns for identification of both chiral and non-chiral organochlorine (OC) pesticides and PCBs; in so doing, the enantiomer fractions of any chiral compounds identified were also measured. p,p’-DDE was the most prominent POP identified, being found in all samples at concentrations ranging from 4 to 779 ng/mL. Trans- and cis-nonachlor were also detected in all samples at a concentration range of 0.3 to 64 ng/mL; p,p’-DDD was also detected in all samples, but at an even lower concentration of 0.2 to 11 ng/mL.. Only a few chiral OC pesticides were identified; their enantiomer fractions were mostly non-racemic, indicating pre-ingestion enantioselective biotransformation or enantioselective metabolism by the alligators. p,p’-Dichlorobenzophenone (p,p’-DCBP), a known metabolite of p,p’-dicofol, was detected in all but one sample; most concentrations were < 1ng/mL. Dicofol is known to have been used and spilled near Lake Apopka, and is highly toxic to fish and aquatic invertebrates. Experiments showed that the p,p’-DCBP identified in these samples occurred via thermal degradation during GC analysis of p,p’-dicofol that was present in the liver sample extracts. No PCBs were detected in these liver samples.

Purpose/Objective:

The main objective of this research is to determine the environmental occurrences, fate, and exposure of the enantiomers of selected chiral pesticides and other chiral organic pollutants. Chiral compounds, which exist as mixtures of enantiomers, include important environmental pollutants.

URLs/Downloads:

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Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 01/15/2010
Completion Date: 01/15/2010
Record Last Revised: 04/22/2010
Record Created: 11/17/2008
Record Released: 11/17/2008
OMB Category: Other
Record ID: 201370

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LAB

ECOSYSTEMS RESEARCH DIVISION

PROCESSES & MODELING BRANCH