Initiated in 1991 by USDA Agricultural Marketing ... QuEChERS â Quick Easy Cheap Effective Rugged Safe ..... Frank Schenck, NACRW 2014 discussion, lead to email with an attachment summarizing ACN extractions of nonpolar residues ...
Photo courtesy of Tammy Best
Brief overview of USDA-AMS-PDP Environmental Contaminants
◦ Purpose of study ◦ Current Analytical Capabilities & Limitations ◦ Extraction Techniques
Method Development Method Validation
These are the personal opinions of the author, assumptions made within the analysis or brand names mentioned are not reflective of any U.S. government entity. Brittany Holmes, WSDA
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National pesticide residue database program ◦ Exposure assessment only ◦ Does not regulate or enforce tolerances
Initiated in 1991 by USDA Agricultural Marketing Service (AMS) Important role in implementation of the 1996 Food Quality Protection Act (FQPA) ◦ Pesticide risk assessments and registration decisions
The findings are published in annual summaries available online at www.ams.usda.gov/pdp within 2 years of study end date Brittany Holmes, WSDA
NACRW 2015 O-1
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Brittany Holmes, WSDA
NACRW 2015 O-1
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Brittany Holmes, WSDA
NACRW 2015 O-1
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Study commodity for 1-2 yrs (700-1400 samples)
◦ Nationwide sampling throughout the year from distribution centers and terminal markets, Domestic and imported, Organic and conventionally grown, etc…
“State of the art” instrumentation and methods
◦ GC-MS/MS, LC-MS/MS, GC-NCI, low ppb range, MultipleReaction-Monitoring (MRM), etc… ◦ Typical screen >200 different pesticides residues
Program wide proficiency testing (internal & external) Use cost-effective, multi-residue techniques ◦ QuEChERS – Quick Easy Cheap Effective Rugged Safe (www.quechers.com) ◦ Single-analyte, derivatization methods typically excluded Not cost effective for size of study
Brittany Holmes, WSDA
NACRW 2015 O-1
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Multi-residue study July 2013 to 2014 Fresh or Frozen Fillets, Wild and Farmed, skin on/off, bone in/out, Atlantic or Pacific (Pacific species limited to: Chinook, Chum, Coho, Pink, and Sockeye) ◦ Collected Nationally in fish markets, distribution centers, terminal markets, and retail sites determined by NASS ◦ Sample information based off of labels ONLY
~59 samples per month
◦ 352 collected & analyzed in 2013 1 sample: Azinphos methyl oxon, Carbendazim, Cypermethrin 2 samples: DDT p,p’
2014 results under final review ECD late 2015
Brittany Holmes, WSDA
NACRW 2015 O-1
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Brittany Holmes, WSDA
NACRW 2015 O-1
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Dry-ice 1 min blend
Dry-ice 2 min blend
Brittany Holmes, WSDA
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(June 2013 to July 2014)
Samples Arrive •2lb whole, frozen or fresh •Stored at -20°C until homogenized
Sample Aliquot & Storage
Homogenize •1lb chopped frozen, including skin
•2x 20g aliquots in 50mL PP centrifuge tube
•Retsch Food Processor
•Stored at -40°C
Brittany Holmes, WSDA
NACRW 2015 O-1
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Analyze samples previously collected for pesticide residue survey
Quick turn-around,
