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APPENDIX II>
ACTION LEVELS, TOLERANCES AND OTHER VALUES FOR POISONOUS OR DELETERIOUS SUBSTANCES IN SEAFOOD

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The types of poisonous or deleterious substances which have been recovered from shellfish include heavy metals, pesticides, petroleum products, polychlorinated biphenyls and naturally occurring marine biotoxins. The source of these contaminates may be from: industry, agriculture, mining, spillage, sewage, dredging operations, sludge dumps and naturally occurring marine organisms.

The Canadian guidelines for poisonous or deleterious substances are as follows:

Total DDT ...........................................> 5 ppm
Polychlorinated Biphenyls (PCB) ..........> 2 ppm
Dioxin ..................................................> 20 ppt
Mercury ..............................................> 0.5 ppm
Mirex ..................................................> 0.1 ppm
PSP ................................................... > 80 µg/100 g
Domoic Acid ...................................... > 20 µg/g
Okadaic acid and/or DTX-1............... > 1 µg/g of digestive tissue*

All other Agricultural Chemicals ...................> 0.1 ppm

The United States FDA action levels/tolerances for fish products may be found in Chapter 10 of the DFO Fish Products Inspection Manual. The following levels of marine biotoxins also apply in the USA:

PSP...................................... > 80 µg/100 g
Ptychodiscus brevis...........20 mouse units/100 g meats

The value for P. brevis toxin(s) represents a level which is deemed by NSSP to be potentially unsafe for human consumption. The value is not an FDA action level or tolerance.

* Health Canada interim standard