TITLE:
Levels of Mercury and Polychlorobiphenyls in Bluefin Tuna from the Western Mediterranean Sea: A Food Safety Issue?
AUTHORS:
Monia Renzi, Alessandro Cau, Nicola Bianchi, Silvano E. Focardi
KEYWORDS:
Bluefin Tuna; Human Consumption; Mercury; PCBs
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.2,
February
26,
2014
ABSTRACT: In this paper,
the presence and amount of mercury and polychlorobiphenyls (PCBs) were
determined in 23 bluefin tuna samples collected in the spring of 2012 in Porto
Scuso (South West Sardinia, Italy) and Villa Putzu (South East Sardinia, Italy)
in order to assess the current levels of these two contaminants in fish muscle
and the consequent risk to humans consuming said fish. Values of
polychlorobiphenyls in bluefin tuna muscle vary between 0.155 and 1.403 mg/kg
f.w.; the average of PCBs in tuna muscle is 0.732 mg/kg f.w. With regard to
PCBs the presence of more elevated concentrations is confirmed in larger fish.
The results regarding mercury in muscle show an average of 0.660 mg/kg f.w. and
mercury values vary between 0.140 f.w. and 2.211 mg/kg f.w.; for mercury as
well, the highest concentrations were found in the largest bluefin tuna. Six
samples, 26% of total, contained more than 1 mg/kg f.w., which is the maximum
level set by the European Commission (EC, Regulation n. 1881/2006) for this
species. Mercury, in particular methylmercury, poses a risk to public health,
therefore, taking into account the important nutritional contribution that tuna
fish makes to the diet, it is advisable that women of childbearing age,
pregnant and breastfeeding women as well as young children strictly limit their
consumption of tuna from this area of the Mediterranean.