Chemical Contaminants & Residues in Food CommunitySubgroup ‘Unknowns’

Collaborative Study

for Determination of Melamine

Report Sept. 2009 – Sept. 2010

124th AOAC Meeting & Exposition

Orlando, FL

26-29 September, 2010

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Renal failure in pets in the Republic of Korea (2004)

Kidney stones in infants fed with Sanlu products (Sept. 2008)

Renal failure in pets in the United State of America (2007)

NH2

NN

NH2H2N N

Deliberate addition to boost apparent protein content

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

WHO / Codex Alimentarius

Maximum levels for melamine in food:

■ 1 mg/kg in powdered infant formula

■ 2.5 mg/kg in foods and animal feeds

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

123rd AOAC Meeting & Exposition (Sept. 13-16, 2009, Philadelphia, PA)

■ Session ‘Fraud in Food and Drug Safety’

■ Session ‘The Threat of the Unknown Contaminants:

When You Don’t Know and What You Don’t Know’

■ Session ‘Finding Non-Target Chemical Contaminants in Food Stuff’

■ Hot topic rountable ‘Dealing with the Unknown – Risk Assessment

and Risk Management Strategies of Industry and Regulators’

► Initiate a project for a Collaborative Study to quantify melamine in foodstuff

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

■ November 2009

People interest

■ January 2010

Call for methods

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Method Performance Criteria

Purpose: Method for the quantitative determination of melamine (and cyanuric acid) in foodstuffs. The purpose of the method is to provide food industry and authorities with a method able to control melamine adulteration and monitor low levels in food.

Applicability: Milk, dairy products, infant formula as well as food raw materials with a high risk of economically driven adulteration.

Analytes: melamine (+cyanuric acid)

Limit of detection: 0.05 mg/kg

Regulatory limits: 1 mg/kg in milk-powder infant formula, and 2.5 mg/kg in other foods

Accuracy (method recovery): 100%

Selectivity (specificity): Should be able to differentiate melamine from cyanuric acid

Repeatability (reproducibility): < 15%

Technology: Mass spectrometry

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Methods ■ HPLC-DAD by Ehling et al.

for melamine (MEL), cyanuric acid (CA), ammeline & ammelide

■ GC-MS by Litzau et al.

for MEL, CA, ammeline & ammelide

■ LC-MS/MS by Smoker & Krynitsky

for MEL & CA

■ LC-MS/MS by Desmarchelier et al.

for MEL & CA

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Milk powder Backing mix

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

A 0.101 0.001 0.156 0.004 0.440 0.006 1.49 0.01

B 0.115 0.000 0.179 0.012 0.486 0.011 1.44 0.05

C 0.100 0.000 0.190 0.028 0.430 0.014 1.52 0.07

D 0.096 0.007 0.182 0.006 0.496 0.006 1.55 0.02

E 0.093 0.001 0.186 0.008 0.483 0.036 1.59 0.06

F 0.069 0.001 0.199 0.010 0.420 0.012 1.55 0.38

G 0.095 0.000 0.130 0.007 0.450 0.002 --

MEL CA MEL CALab.

Egg powder Soya Protein

Results expressedas mg/kg

Fortification levels: Egg powder: 0.10 mg/kg for melamine, and 0.15 for cyanuric acidSoya protein: 0.50 mg/kg for melamine, and 1.50 for cyanuric acid

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

LC-MS/MS 10.44 + 0.3 3.20 0.0

GC-MS 9.46 - 0.5 3.02 - 0.4

HPLC-UV 9.55 - 0.5 2.73 - 1.1

ELISA 11.8 + 1.5 3.4 + 0.5

Result z-score Result z-score(mg/kg) (mg/kg)

Skimmed milk powder Backing mix

Assigned values: Skimmedmilk powder: 10.0 mg/kgBacking mix: 3.18 mg/kg

IRMM: Institute for Reference Materials and Measurements

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

■ NQAC-Cergy (France) …………….. 8’900 on-going

■ NQAC-Tianjin (China) ………..…….. 900 on-going

■ R&D-Beijing (China) ……….……….. 550 not applicable

■ NQAC-Singapore ………………..... 6’900 accredited

■ NQAC-São Paulo (Brazil) ……...... 1’700 accredited

Number of analyses(update April 2010)

Methodaccreditation

Overall 18’350

■ Spiked samples *

Powdered infant formula

Egg powder

Soya protein

Cereal and/or dry vegetables

Dried powdered shrimps

■ Incurred samples

Dried mushrooms

Feed

* Each sample at four levels: blank, below maximum limit (ML), ML, above ML

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Chemical Contaminants & Residues in Food CommunityCollaborative Study for Determination of Melamine

Thierry DELATOUR

Group Authenticity & Adulteration

Department Quality & Safety

Nestlé Research Centre

Vers-chez-les-Blanc

1000 Lausanne 26, Switzerland

Phone: +41.21.785.9220

E-mail: thierry.delatour@rdls.nestle.com