Pesticides Subgroup

At the AOAC Annual Meeting, Tuesday, August 28, 2018 6:15 - 7:45 pm

1.  Attendance

There were about 30 people attending the  subgroup meeting.  The chair has included everyone in the email distribution  list to  receive future subgroup updates. Please email Ping if you would like to   opt out. 

2. Ongoing Collaborative Studies

  • AOAC Collaborative Study: using nDATA for the  screening  of pesticides in fruits and vegetables. Study based on the work led  by  CFIA:  J. Agric. Food Chem. 2017, 65  (2), 473-493. Development and  validation of a qualitative method for target  screening of 448  pesticide residues in fruits and vegetables using UHPLC/ESI  Q-Orbitrap  based on data-independent Acquisition and compound database.  Labs  interested please contact Dr. Jon Wong,  FDA and Dr. Jian Wang, CFIA. 
  • Collaboration has been done by these three   laboratories:  Canadian Food Inspection  Agency, California Department  of Food and Agriculture, US Food and Drug  Administration/CFSAN. Now  expanding the study to more labs. 
  • Proposed study has three phases/requirements: 
    • Qualification: Inject standards at 5 ng/mL and determine  threshold based on pesticide response
    • Validation
  • Matrix studied:   apple, banana, broccoli, carrot, grape, lettuce, orange, potato,    

   strawberry,  tomato

  • Sample prep: QuEChERS (AOAC.2007.1)
  • Pesticides: 50  
  • Spike concentrations:  10 and 100 ppb (duplicates at each  concentration)
    • Proficiency
  • Unknown pesticides: 0 – 50
  • Concentration:   5 – 100 ppb (duplicates of each commodity)

3. Topics of Discussion

  • Pesticides in cannabis   

A very active AOAC cannabis working group.  SMPR in the  works. Check AOAC website for more information regarding the  workgroup  progress. 

  • Future collaborative study on glyphosate  residue in food and environmental samples 
  • Currently  no AOAC official methods available
  • Great interest shown by the 2018 survey  results 
  • Two main methodologies  available (direct analysis and derivatization by FMOC)   
  • Matrices to  be considered: vegetation, soil, water, surface swabs, animal tissue, foods,  grains, honey, animal feed etc. 
  • Many attendee  labs expressed interest in participating the future collaborative work.  
  • There were  suggestions in the meeting to work with NIST to develop glyphosate Standard  Reference Materials. 
  • First step: calling a workgroup leader. Need a  glyphosate workgroup to develop a SMPR. 
  • Acid herbicides residue method needs 
  • Currently no AOAC official methods  available.  The  community definitely have  a strong interest in having a standardized  method on Acid Herbicides.  
  • Dicamba agriculture  crisis since 2017: method needs to  include Dicamba and its two major  metabolites due to the short  half-life of Dicamba. 
  • Compounds of  Interest (by popularity indicated by the survey): 

1          2,4-D  
         2          Dicamba  (including metabolites 5-OH Dicamba, DCSA)      
         3          Triclopyr         
         4          MCPA 
         5          Aminopyralid 
         6          MCPP 
         7          Clopyralid       
         8          Picloram         
         9          Fluroxypyr      
         10        2,4-DB
         11        2,4-DP
         12        Diflufenzopyr 
         13        Bentazon        
         14        Aciflurofen     
         15        Bromoxynil     
         16        All  of above by HRMS screen 

  • Represented  matrix to be studied: vegetation, soil,  water, surface swabs, animal  tissue, processed foods, grains, milk  product, animal feed etc.
  • Calling a workgroup leader. Need a  workgroup formed to discuss SMPR. 

4. Presentation:  Improved residue  analysis of captan, captafol, folpet, iprodione, paraquat and  diquat  in fruits and vegetables by ultra-performance liquid chromatography –   tandem mass spectrometry

Dasharath Oulkar,  Raviraj Shinde, Zareen Khan, Kaushik Banerjee
         National Referral  Laboratory, ICAR National Research Centre for Grapes

Dr. Banerjee  presented improved ways of analyzing this  group of difficult compounds. Please  contact him for details if  interested. 

5. Presentation:  Combination of GC/LC-Q-TOFMSMulti-Residues Screening Method for 733  Pesticides in Fruits and Vegetables- Proposing a AOAC Collaborative Study

Guo-Fang Pang
         Chinese Academy  Inspection and Quarantine, P.R. China 

Collaborators  are invited! Please contact Dr. Pang for details regarding this GC and LC HRMS  AOAC collaborative study. 

6. Future  Meetings 

  • NACRW - July  21-24, 2019 Naples, FL
  • AOAC - September 8-11, 2019, Denver, CO 

Subgroup Chair


Ping  Wan 

Office of the Indiana State Chemist,

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