Improved Efficiency in Screening for Organochlorine/Phosphate Pesticides in Fruits and Vegetables

PACIFIC NW POLLUTION PREVENTION RESOURCE CENTER
POLLUTION PREVENTION RESEARCH PROJECTS DATABASE

Project Name: Improved Efficiency in Screening for Organochlorine/Phosphate Pesticides in Fruits and Vegetables

Date Last Updated: 9/98

Project Summary:
OBJECTIVES: To develop and improve the Connecticut Agricultural Experiment Station (CAES) methodology for pesticide residues in crops using microwave assisted solvent extraction, coupled with solid phase extraction cleanup. Initial investigations show that microwave extraction will produce sample extracts with pesticide recoveries that are comparable to the CAES method. Preliminary solid phase extractions have shown that clean-up and recovery of pesticides in a fruit juice matrix are possible and that with optimization of the extraction step, a workable method that generates less solvent waste is possible. The results of the analysis of fruit and vegetable samples using the proposed method will be reported in Station bulletins, along with publication of the method.

PROGRESS: Five crops---beets, cucumbers, lettuce, peppers, and tomatoes---were grown and treated in the field with seven pesticides---dacthal, chlorpyrifos, chlorothalonil, diazinon, permethrin, methoxychlor, and azinophos-methyl. The microwave extraction of these pesticides from the crops was studied by determining time and temperature settings which produced optimal recovery. The optimal values of time and temperature depended on both crop matrix and pesticide. For example, recovery of chlorothalonil was highly dependent on which time and temperature values were employed.

Using the selected values of time and temperature, pesticide recoveries from the microwave extraction were compared with recoveries from the conventional extraction method. Statistical comparison indicated that pesticide recoveries and method reproducibility of microwave extraction compared favorably with the conventional method. Furthermore, the selected reduction in sample mass and solvent volume does not affect the data.

As a result of this study the Station now uses 50% less organic solvent in our routine screening of foods for pesticide residues.

Project Keywords: pesticide, fruit, vegetable, crop, solvent, extraction, microwave, residue

Organization Performing Research: The Connecticut Agricultural Experiment Station

Primary Research Contact:
Harry M. Pylypiw
Dept. Analytical Chemistry
The Connecticut Agricultural Experiment Station
123 Huntington St.
P.O. Box 1106
New Haven, CT 06504-1106
Voice (203) 974-8456 Fax (203) 974-8456
E-mail: pestman@caes.state.ct.us

Date Research Started/Completed: 4/96 - 4/99

Publications Based on Research:
1. PYLYPIW, H.M., MISENTI, T.L., AND MATTINA, M.J.I. 1997. Pesticide residues in produce sold in Connecticut 1996. Bulletin 940. The Connecticut Agricultural Experiment Station, New Haven, CT.
2. PYLYPIW, H.M., ARSENAULT, T.L., THETFORD, C.M., AND MATTINA, M.J.I. 1997. Suitability of microwave assisted extraction for multiresidue pesticide analysis of produce. J. Agric. Food Chem. 45:3522-3528.

Approximate Project Budget: no information provided

Primary Project Funder: U.S. Department of Agriculture, Cooperative State Research, Education and Extension Service (CSREES)
Accession No: 0171242 Subfile: CRIS
Proj. No.: CONH00129 Agency: CSRS CONH
Proj. Type: HATCH Status: NEW

Funder Contact:
Secretary
U.S. Department of Agriculture
Cooperative State Research, Education and Extension Service (CSREES)
Current Research Information System
National Agricultural Library Building, 5th Floor
10301 Baltimore Avenue
Beltsville, MD 20705
Phone: (301) 504-6846; Fax (301) 504-6272
E-mail: crisadm@cris.nal.usda.gov