Lab Matters Summer 2017 - Page 22

environmental health / food safety

Understanding Pesticide Testing Interfaces Between Laboratories and the US EPA

by Keith Wegner , MS , laboratory services section chief , Colorado Department of Agriculture ; Gareth Horvath , laboratory director , Minnesota Department of Agriculture ; Lucio Barinelli , PhD , technical director , water analysis laboratory , New Hampshire Public Health Laboratories ; Susan Chabot , laboratory scientist IV , New Hampshire Public Health Laboratories ; Thuy Nguyen , branch chief , US EPA Office of Pesticide Programs , Analytical Chemistry Branch ; Robyn Randolph , MS , specialist , Food Laboratory Accreditation ; and Sarah Wright , MS , senior specialist , Environmental Laboratories
The Federal Insecticide , Fungicide and Rodenticide Act ( FIFRA ) gives the US Environmental Protection Agency ( US EPA ) the authority to regulate the registration , distribution , sale and use of pesticides . All states except Wyoming have been granted primary enforcement responsibility for pesticide use / misuse violations by US EPA . To support enforcement , pesticide residue and formulation data are commonly generated at state agricultural laboratories , but in some states , the public health or environmental laboratory may have this responsibility . To better understand how pesticide testing varies by state and how these laboratories interact with US EPA , APHL discussed this topic with representatives from Colorado and Minnesota agricultural laboratories , New Hampshire Public Health Laboratories and US EPA ’ s Analytical Chemistry Branch .
The New Hampshire Public Health Laboratories receives herbicide tank , concentrate and residue samples for testing in use / misuse investigations . Photo by Sue Chabot
How is your laboratory involved in pesticide testing ?
Wegner : The Colorado Department of Agriculture Biochemistry Laboratory has a staff of 14 and analyzes just over 1200 samples per year for pesticide residues in cannabis , groundwater , surface water , vegetation , soils and miscellaneous matrices ( clothing , animal / fish tissues , turf , etc .). The laboratory ’ s pesticide testing methods are on the ISO 17025 Chemical Testing scope .
Horvath : The Minnesota Department of Agriculture Laboratory Services Division has 14 employees and processes an average of 2,409 samples per year for 119,981 analytes . The laboratory is divided into two sections : one that analyzes pesticide residues in susceptible streams and aquifers and another that supports departmental pesticide incident investigations including misuse , misapplication , human / animal exposure , drift , bee kills and spills . The water analysis unit of the laboratory employs three liquid chromatography tandem mass spectrometry ( LC / MS / MS ) methods to analyze for 110 pesticides and two gas chromatography tandem mass spectrometry ( GC / MS / MS ) methods to analyze for 40 pesticides . These are ISO / IEC 17025:2005 accredited . Other method accreditations that we hold are for analyzing unique combinations of target analytes and matrices that often do not have established methodologies . This might be a food or vegetation sample with pesticide drift from a compound not registered for use on that commodity .
Barinelli / Chabot : The New Hampshire Public Health Laboratories are accredited by The NELAC Institute . We have one fulltime employee to analyze approximately 200 pesticide samples per year (~ 400 analyses ). We partner with the state ’ s Pesticide Control Division to analyze use / misuse samples , complaints , label claim verifications and to conduct a few special projects . Matrices include pesticide concentrates , pesticide applicator tank samples , residues ( vegetation and wipe samples ) and water .
How has your laboratory ’ s pesticide testing helped to improve public health ?
Wegner : The laboratory ’ s pesticide residue testing program and increased inspections have significantly reduced pesticide usage in cannabis grow operations . In fiscal year 2015-2016 , this reduction was more than 30 %.
Horvath : Some direct human-pesticide exposure samples can be used for medical diagnosis and treatment . However , most pesticide data are used to identify or determine chronic exposure , and support regulatory actions or practices designed to minimize exposures .
LAB MATTERS Summer 2017
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