Toxic Squid Snack?

Recently Hong Kong consumer council published some results on arsenic analysis in dried squid snack. I can't resist commenting how misleading these statements were given. As a result, different newspapers quoted these slightly differently and confused people more. In the press release on Apr 16, 2007 (taken from CHOICE magazine issue #366), it said:
"The health warning followed a Consumer Council test on 65 samples of dried meat products comprising 15 dried beef, 14 dried pork, 13 pork floss, 23 shredded squid and dried fish, sourced from local outlets.
Under the law, the maximum permitted levels of arsenic in squid and fish are 10 mg/kg and 6 mg/kg respectively. In the test, the amount of arsenic found in 8 shredded squid samples ranged from 12.7 mg/kg to 35.3 mg/kg and 1 dried fish sample 7.7 mg/kg.
In one shredded squid sample, the total arsenic (both organic and inorganic) found was a high 35.3 mg/kg.
It is stipulated in the Provisional Tolerable Weekly Intakes (PTWI) of JECFA (Joint FAO/WHO Expert Committee on Food Additives) that the amount of inorganic arsenic that can be ingested weekly for a 60 kg person is 0.9 mg.
So, consuming three packages (90 g each) of the sample detected with 35.3 mg/kg total arsenic (assuming 10% of it was inorganic) in a week may already have exceeded the weekly tolerable level.
The Consumer Council has referred the findings of arsenic in these popular snacks to the Centre for Food Safety (CFS) for suspected breach of the Food Adulteration (Metallic Contamination) Regulations."

Arsenic is 'well known' for being toxic. However, not everyone knows that arsenic exists as different forms, toxic inorganic form and non-toxic organic form. The most common form of organic arsenic compound in seafood, arsenobetaine, will be excreted in urine within a couple of days after consumption. Total arsenic concentration could only be used as a guildline but not a true indicator of the toxicity. In fact, 'assuming' 10% of total arsenic in squid was inorganic arsenic is incorrect. According to previous studies less than 1% of total arsenic in squid is the toxic inorganic form.

If you want to spend time worrying about consuming too much arsenic from seafood products, you may as well worry about the water you drink and the rice you eat. According to the data from US, the amount of inorganic arsenic taken by an average adult per day from seafood is negligible compared with that from rice, vegetables and water. Since the arsenic compounds are mostly organic arsenic in seafood it can't even be linked up to the word 'toxicity' in this regard.