I have cocoa powder for breakfast every morning (mixed with yoghurt, fruit, nuts). Since my understanding is that cocoa powder will have the highest concentration of heavy metals (relative to other chocolate products), I wanted to do an extremely quick investigation to see if I reached a similar conclusion to you.
From consumerlabs.com (I haven't paid for their full report yet, just viewing the free summary): "most cocoa powders to have high concentrations of cadmium -- around 1 to 1.5 mcg per gram -- which is much higher than the World Health Organization limit of 0.3 mcg per gram. The dark chocolate bars we tested had concentrations which were about 1/10th the amount found in cocoa."
The serving size for the cocoa powder I have currently is 1 Tbsp=5 g. I would estimate I use less than 1 Tbsp in my daily scoop (maybe 3 g), but I'll stick w 5 g as an upper limit.
Assuming that my brand has an above average cadmium concentration (in reality, I have no idea), let's say 2 mcg/g.
So perhaps I'm getting (5 g)*(2 mcg/g)=10 mcg of cadmium per day from cocoa powder.
You cite the EPA limit as 1µg/kg/d. I found a source that says "The EU has set a TWI (tolerable weekly intake) limit for cadmium of 2.5 µg/kg body weight"--this is 0.35 µg/kg/d.
I weigh about 55 kg, so my limits would be 55 mcg/d (EPA) or 19 mcg/d (EU).
So my cadmium consumption from cocoa powder alone could be about half the EU limit for total cadmium consumption. This is not scarily high, but doesn't seem great either, since there are significant sources of cadmium in the diet besides chocolate. This study of Americans says: "The average dietary Cd consumption in the population was 4.63 μg/day, or 0.54 μg/kg body weight/week, which is 22% of the tolerable weekly intake (TWI) of 2.5 μg/kg body weight/week." This study of Belgians says: "The population mean, median and 95th percentile of the dietary intake values were 0.98, 0.85 and 2.02 µg kg⁻¹ body weight per week respectively. Two percent of the Belgian adult population has a dietary Cd intake above the recent TWI of 2.5 µg kg⁻¹ body weight established by EFSA in 2009. Cereal products and potatoes contribute for more than 60% to Cd intake."
So my personal conclusions:
I would definitely buy low-cadmium cocoa powder if it were easy to buy and easy to identify (and have confidence in the measurements, etc)
Assuming I can't find a good source of low-cadmium cocoa powder, I haven't really decided whether I will reduce my consumption of cocoa powder. Probably I will just because the cost of not eating cocoa powder seems low to me. But I won't really obsess over it.
I have cocoa powder for breakfast every morning (mixed with yoghurt, fruit, nuts). Since my understanding is that cocoa powder will have the highest concentration of heavy metals (relative to other chocolate products), I wanted to do an extremely quick investigation to see if I reached a similar conclusion to you.
From consumerlabs.com (I haven't paid for their full report yet, just viewing the free summary): "most cocoa powders to have high concentrations of cadmium -- around 1 to 1.5 mcg per gram -- which is much higher than the World Health Organization limit of 0.3 mcg per gram. The dark chocolate bars we tested had concentrations which were about 1/10th the amount found in cocoa."
The serving size for the cocoa powder I have currently is 1 Tbsp=5 g. I would estimate I use less than 1 Tbsp in my daily scoop (maybe 3 g), but I'll stick w 5 g as an upper limit.
Assuming that my brand has an above average cadmium concentration (in reality, I have no idea), let's say 2 mcg/g.
So perhaps I'm getting (5 g)*(2 mcg/g)=10 mcg of cadmium per day from cocoa powder.
You cite the EPA limit as 1µg/kg/d. I found a source that says "The EU has set a TWI (tolerable weekly intake) limit for cadmium of 2.5 µg/kg body weight"--this is 0.35 µg/kg/d.
I weigh about 55 kg, so my limits would be 55 mcg/d (EPA) or 19 mcg/d (EU).
So my cadmium consumption from cocoa powder alone could be about half the EU limit for total cadmium consumption. This is not scarily high, but doesn't seem great either, since there are significant sources of cadmium in the diet besides chocolate. This study of Americans says: "The average dietary Cd consumption in the population was 4.63 μg/day, or 0.54 μg/kg body weight/week, which is 22% of the tolerable weekly intake (TWI) of 2.5 μg/kg body weight/week." This study of Belgians says: "The population mean, median and 95th percentile of the dietary intake values were 0.98, 0.85 and 2.02 µg kg⁻¹ body weight per week respectively. Two percent of the Belgian adult population has a dietary Cd intake above the recent TWI of 2.5 µg kg⁻¹ body weight established by EFSA in 2009. Cereal products and potatoes contribute for more than 60% to Cd intake."
So my personal conclusions:
I didn't look into lead.