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Dioxins, dl-PCBs and ndl-PCBs in feed of plant origin (P1408-RT)

PROOF-ACS offered a ring test related to
PCDD, PCDF, dl-PCBs and ndl-PCBs
in feed of plant origin in November 2014.

Scope of the ring test:

  • six non-dioxin-like PCBs
    (PCB 28, 52, 101, 138, 153, 180),
  • twelve dioxin-like PCBs
    (PCB 77, 81, 126, 169, 105, 114, 118, 123, 156, 157, 167, 189), and
  • seventeen PCDD/Fs, all 2,3,7,8-substituted
    (2378-Tetra-CDD/F, 12378-Penta-CDD/F, 123478-Hexa-CDD/F,
    123678-Hexa-CDD/F, 123789-Hexa-CDD/F, 1234678-Hepta-CDD/F, 23478-Penta-CDF, 234678-Hexa-CDF, 1234789-Hepta-CDF, Octa-CDD/F)

No information on the exact identity or the exact number of congeners was provided to the laboratories in advance.


Test material:
200 g of a lucerne (powder made of lucerne pellets) was provided as test material. Unspiked (blank) material was available upon request.

The lucerne powder was spiked with: 

  • ndl-PCBs: PCB 101, PCB 138, PCB 153
  • dl-PCBs: PCB 126, PCB 169, PCB 105, PCB 118, PCB 156
  • PCDD/F: 2,3,7,8-TCDD, 1,2,3,7,8-PCDD, 2,3,7,8-TCDF, 2,3,4,7,8-PCDF

In addition, the lucerne contained five non-spiked (incurred) congeners:

  • PCB 77,
  • PCB 157, 
  • PCB 167,
  • 1,2,3,4,6,7,8-HepCDD, and
  • OCDD

The participants were asked to report:

  • analytical results of each congener separately

Time schedule:

The dispatch of samples was: November 18, 2014 and
the deadline for results reporting was: December 4, 2014.

The statistical evaluation of the test includes the comparability (z-score) and the trueness (70 to 120% of the spiked level).

We would like to invite you to have a look a the summary of results for more details.

The participation fee was 790 EUR (shipment included). Blank material was provided at a price of 70 EUR.

Surplus test material is offered as validated reference material.