Analysis of pesticides, POPs and emerging contaminants in catfish
Yelena Sapozhnikova
United States Department of Agriculture,
Agricultural Research Service, Wyndmoor, PA, USA
Omega-3 fatty
acids:
Amino acids:
Vitamins:
Niacin: 2.105 mg
Vitamin B-12: 2.88 mg
Vitamin A: 1 mg
Vitamin E: 0.81
Vitamin D (D2+D3): 0.2 µg
Vitamin D: 9 IU
Vitamin K: 2.1 µg
20:5 n-3 (EPA): 0.015 g
22:6 n-3 (DHA): 0.057 g
Leucine: 1.153 g
Lysine: 1.386 g
Aspartic acid: 1.487 g
Arginine: 0.951 g
Alanine: 0.860 g
Nutrients per 100 g
Organic contaminants
POPs
PCBs
Toxic stable OC pesticides
PBDEsPAHs
Emerging environmental contaminants
Flame retardants
• Phase-out of some PBDE commercial mixtures => increasing number of alternate flame retardant chemicals
• Large volume production chemicals used in textiles, electronics and other consumer products
Multi-class, multiresidue method
Pesticides
Polychlorinated biphenyls (PCBs)
Polycyclic aromatic hydrocarbons (PAHs)
Polybrominated diphenyl ethers (PBDEs)
Novel alternate flame retardants (FRs)
250
total
• Add 10 mL MeCN
• shake 10 min on vortex shaker
10 g of homogenized tissue + Internal
standards
• Add 4 g anh. MgSO4 & 1 g NaCl, shake 1 min
• centrifuge 3 min at 4150 rpm
Phase separation
• Add 1 mL extract to 150 mg anh. MgSO4, 50 mg Z-Sep
• Shake 1 min, centrifuge, filtrated-SPE cleanup
Sapozhnikova, Journal of Agricultural and Food Chemistry, 2014, 62, 3684-3689
150 pesticides, 50 environmental contaminants & 12 internal standards
16
>200 analytes in 10 min
Low pressure (vacuum outlet) GC
Solvent delay
Method validation
Accuracy: 72 - 120%
p,p’-DDT - 52%
p,p-DDD – 45%
PCBs
PBDEs
Pesticides
PCBs
PAHs
Pesticides
IS: atrazine-d513C12-p,p’-DDE
Catfish analysis
• Farm raised catfish samples
• USA: catfish• Vietnam: swai• China: catfish & basa• Cambodia: swai
•
“In aquaculture products imported from Viet Nam, there
were notifications for trifluralin in Pangasius spp.
products, three of which also contained chlorpyriphos”.