I reproduce the abstracts of the following two paper for your perusal. Pls look in the values given in square brackets. Both give almost same values as:

in first reference, Co =0.04-0.26mg/ Kg and

in the second reference ,Co= 0.05- 0.28 mg/Kg

[I] J. Chil. Chem. Soc, 53, N° 1 (2008)

METAL CONTAMINATIONS IN FIVE FISH SPECIES FROM BLACK, MARMARA, AEGEAN AND MEDITERRANEAN SEAS, TURKEY

MUSTAFA TURKMEN, AYSUN TURKMEN, YALQIN TEPE

Abstract: The concentrations of cadmium, copper, chromium, copper, iron, manganese, nickel, zinc and lead in muscle and liver tissues of the fish samples collected from seven stations in the coastal waters of Turkey and were determined. Iron showed the highest levels in both tissues offish and all stations. Following Fe; Zn generally showed the second highest levels. Metal concentrations in edible parts offish species were 0.02-0.30 mg kg"' for cadmium,[ 0.04-0.26 mg kg"' FOR COBALT], 0.07-1.19 mgkg"' for chromium, 0.34-16.7 mgkg"' for copper, 18.5-72.3 mgkg"' for iron, 0.07-2.58 mgkg"' for manganese, 0.01-2.78 mgkg"'for nickel, 0.04-1.34 mg kg"' for lead, 3.36-42.6 mg kg"' for zinc respectively. In general, metal concentrations in livers were higher than those in muscles. Cadmium, chromium and lead concentrations in muscles of fish from some stations were higher than permissible safety levels for human uses.

{II}International Journal of Animal and Veterinary Advances 1(1): 10-14, 2009.

Heavy Metals Concentration in Four Commercially Valuable Marine Edible Fish

Species from Parangipettai Coast, South East Coast of India

P. Raja, S. Veerasingam, G. Suresh, G. Marichamy and 1R. Venkatachalapathy

Abstract: Concentrations of Chromium (Cr), Cadmium (Cd), Copper(Cu), Iron (Fe), Magnesium (Mg),Manganese (Mn), Nickel (Ni), Cobalt (Co), Zinc (Zn) and Aluminium(Al) were determined in four edible partof the marine fish species (Nematolosa nasus, Aleper para, Atropus atropus and Parastromateus niger) from

Parangipettai Coast, south east coast of India in September 2008 to understand the toxicity of such heavymetals. Heavy metal concentrations were measured using Inductively Coupled Plasma-Optical EmissionSpectrometer (ICP-OES). Concentrations of the heavy metals in examined fish species ranged as follows: Cr0.65 – 0.92; Cd 0.18 – 0.54; Cu 0.12 – 0.31; Fe 24.1 – 50.3; Mg 0.54 – 1.21; Mn 0.31 – 1.20; Ni 0.38 – 1.54;[Co 0.05 – 0.28]; Zn 14.1 – 33.5 and Al 14.1 – 33.5 :g/g. Cd concentration increases gradually as weight andlength of the fish increases. Heavy metals in the edible parts of the investigated fish were in the permissiblesafety levels for human uses.

No permissible limit value is currently specified by the FDA, however, a provisional peer reviewed toxicity values (PPRTV) RfD of 0.0003 microgram/kg/day is currently in use(see https://semspub.epa.gov/work/HQ/403662.pdf), though some authors argue that the value is highly conservative and should be revised to 0.03 microgram/kg/day instead