Technical note: evaluation of extraction methodologies for the determination of an organochlorine pesticide residue in vegetation.

Numerous extraction methodologies are used to quantify pesticide levels in vegetation. Sample availability, resource use, efficiency, time consumption, space allocation, and cost vary considerably among the commonly employed techniques. A study was conducted to compare the efficiency of microwave assisted extraction (MAE), blender homogenized extraction (BE), Soxhlet extraction (SE), the QuEChERS ("Quick, Easy, Cheap, Effective, Rugged, and Safe") method, and a simple oven assisted extraction (OAE), to recover p,p'-DDE from the tissues of Cucurbita pepo. A hot-solvent soak of stem or root tissues in a 2-propanol/hexane mixture, OAE yields recoveries that are statistically equivalent to the other procedures. The method recovered 1800 +/- 190 ng g(-1) and 8100 +/- 900 ng g(-1) (BCF = 87 +/- 9.7) p,p'-DDE from stem and root tissue, respectively. Recoveries for the other methods ranged from 1400-2200 ng g(-1) for the stems and 3600-7200 ng g(-1) for the roots. Statistical analyses for stem and root extraction indicate that there is no significant difference among the variances of each method. Given its simplicity, precision, and efficiency, OAE appears to be suitable for the extraction of an organic pollutant such as p,p'-DDE from plant tissues and for use in phytotechnology development and risk assessment.