Subject: Lead and Fish

From: [email-masked] (MarkBlake7)
Date: 26 Apr 1996 18:13:41 -0400

Does anyone know the amount of lead present in fish (mg/kg) that will pose
a toxicity risk and/or carcinogenic risk (yes, even lead may be a
carcinogen) of 1 out of 1 million people assuming an average consumption
of  20 g/day of fish and a lifespan of 70 years?

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From: [email-masked] (Allan Johnson)
Date: 29 Apr 1996 20:08:02 GMT

>of  20 g/day of fish and a lifespan of 70 years?

Background levels of lead in freshwater sportfish in Ontario are 
generally less than 0.6 ppm in the edible flesh.
Levels in whole fish will be considerably higher since about 85% of the 
lead in fish is in the bony parts (bones and scales).
At one time lead up to 10 ppm was acceptable in fish (generally levels 
were higher in tinned fish because of solder from the can) but currently 
criteria of 2 to 3 ppm are more common. Thius assumes the lead is in the 
inorganic form and that the consumer is an adult assimilating about 10% 
of the lead from the edible flesh portion.

If lead is in the organic form such as tetraethyl/tetramethyl lead from 
gasoline assimilation is more like 100% and the potential toxicity is 
much greater.

What form of lead are you concerned about?

The 20gm/day is too high for most fish consumers except sport anglers or 
people living off the land.

Allan Johnson