The influence of industrial-scale canning on cadmium and lead levels in sardines and anchovies from commercial fishing centres of the Mediterranean Sea

Abstract

The current study encompassed a survey on the levels of toxic trace elements in two highly consumed fish species in commercial fishing centres of western, central and eastern Mediterranean Sea. A Zeeman GTA-AAS graphite furnace atomic absorption spectrometry system was used throughout the study. Toxicological evaluation of the samples revealed a low Cd content in the raw samples, ranging between 0.003 and 0.027 mg kg⁻¹. Pb presented significantly higher values, from 0.037 to 0.297 mg kg⁻¹, occasionally reaching the limit of 0.3 mg kg⁻¹. Heavy metal levels were particularly higher in bones, thus raising queries about the safe consumption of fish intended to be eaten as a whole, a very common practice for small fish and canned products. The influence of industrial-scale canning showed that canning enhanced heavy metal levels by 35%–80%. The effect of canning depended on metal type and reduction of moisture loss after the steam-roasting step of the canning procedure.

Keywords:

• canned fish
• fish and fish products
• environmental contaminants
• heavy metals
• cadmium
• lead

Acknowledgements

The authors would like to thank North Aegean Sea Canneries S.A. for technical support.