40 N. East Street, Suite B Woodland, CA 95776 (530) 666-6890 Fax: (530) 666-2987
Questions? Just call or E-Mail customerservice@emalab.com
Specializing in Pesticide Residue Analysis...
Environmental Residue Analysis
Import/Export Support Services
EPA Method 8081A Reporting Limits
EPA Method 8141A Reporting Limits
Multi-Residue Screens
A large number of pesticides can be determined by the various Multi-residue screens. These analytical procedures were developed by scientists at state and federal governmental agencies to detect many compounds of specific chemical classes.
CDFA Screens (Applicable for Produce, Plant Tissue, Soil and Water)
CDFA methods, developed by the California Department of Food and Agriculture (CDFA), are a specialty of EMA. The State of California uses these same methods for rapid determination of a large number of pesticides in a wide variety of crops for its enforcement programs. The general procedure involves extraction of the pesticides from the matrix into acetonitrile, followed by solvent exchange, sample clean-up, and analysis. In general, these compounds fall into the classes of Organochlorines (OC), Organophosphates (OP), Organonitrogens (ON) and Carbamates (CB). Specific detectors are used to get to low detection limits.
Organochlorine Screens: Electron capture detectors are sensitive to chlorine and fluorine containing pesticides for OC's such as DDT, Captan and Dicofol. An extensive list of the routinely screened compounds and their detection limits is contained at OCs. We now offer the Synthetic Pyrethroids as a separate sub-set of the analysis for no additional charge!
Organophosphate/Organonitrogen Screens: Organophosphates and Organonitrogens, such as Malathion, Diazinon and Simazine, are determined using nitrogen/phosphorus detectors and flame photometric detectors. An extensive list of the routinely screened compounds and their detection limits is contained at OP/ONs.
Carbamate Screens: Carbamates, such as Sevin and Aldicarb, are determined by High Performance Liquid Chromatography using post-column derivitization, since they are not stable at temperatures used in gas chromatography. An extensive list of the routinely screened compounds and their detection limits is contained at CBs.
Ethylene-bis-dithiocarbamate Screens: EBDC's, such as Maneb and Thiram are determined by EMA using a proprietary modification of the CDFA procedure. This modification dramatically reduces false positive results for this test. Our low detection limits and high selectivities are possible only through EMA. A list of the routinely screened compounds and their detection limits is contained at EBDCs.
40 N. East Street, Suite B Woodland, CA 95776 (530) 666-6890 Fax: (530) 666-2987
Questions? Just call or E-Mail emalab@yolo.com
Specializing in Pesticide Residue Analysis...
Environmental Residue Analysis
EPA Method 8081A Reporting Limits
EPA Method 8141A Reporting Limits
FDA Screens (Applicable for Produce and Plant Tissue)
FDA methods were developed by the United States Food and Drug Administration and are also available through EMA. The same classes of pesticides (OC, OP, ON and CB) are determined by the FDA methods as for the CDFA methods, and generally the same specific detectors are used.
Method 302. This method, called the Luke method, was developed to detect the OC, OP, ON & CB pesticides in non-fatty foods. This multi-residue screening method uses extraction of the pesticides by acetone, followed by solvent exchange, sample clean-up, and a second solvent exchange prior to analysis. Although these methods allow for somewhat lower detection limits for some pesticide metabolites, the longer procedures and greater solvent requirements make them slower and more expensive than CDFA Screens. A list of the compounds determined by the Luke method, and their method detection limits is found at FDA 302.
Method 221. This method was developed to determine the chlorinated herbicides such as 2,4-D, MCPA and dicamba, which cannot be determined by Method 302. A list of the compounds determined by Method 221, and their method detection limits is found at FDA 221.
FDA Import Screen. Environmental Micro Analysis is now offering a Multi-residue screen which duplicates that performed by the US Food and Drug Administration on imported products. We employ the same extraction procedures, the same sample clean-up methods, run the analysis on the same model GC/MS, and even use splits of the same standard mixtures that FDA uses to identify and quantify pesticide residues!
40 N. East Street, Suite B Woodland, CA 95776 (530) 666-6890 Fax: (530) 666-2987
Questions? Just call or E-Mail emalab@yolo.com
Specializing in Pesticide Residue Analysis...
Environmental Residue Analysis
EPA Method 8081A Reporting Limits
EPA Method 8141A Reporting Limits
EPA Methods (Applicable for Soil and Water)
Where lower detection levels are needed for a rage of compounds, methods developed by the U. S. Environmental Protection Agency can be used. These multi-residue methods, while validated for a specific list, can frequently be used for other compounds within the same class, as well.
EPA Method 8318. This method is useful to determine compounds in the carbamate class, like sevin, thiodicarb, etc. A list of the compounds and their detection limits are contained at 8318.
EPA Method 8081A. This method is useful to determine compounds in the organochlorine class, such as DDT, Toxaphene, etc. A list of the compounds and their detection limits are contained at 8081A.
EPA Method 8141A. This method is useful to determine compounds in the organophosphate and organonitrogen classes, such as parathion, diazinon, etc. A list of the compounds and their detection limits are contained at 8141A.
EPA Method 8151A. This method is useful to determine compounds in the phenoxy acid herbicide class, like 2,4-D, dicamba, etc. A list of the compounds and their detection limits are contained at 8151A.
EPA Method 619. This method is useful to determine compounds in the organonitrogen class, specifically the triazines like atrazine, simazine, etc. A list of the compounds and their detection limits are contained at 619.
EPA Method 632. This method is useful to determine compounds in the phenylurea class, like diuron, monuron, etc. A list of the compounds and their detection limits are contained at 632.