Cadmium Accumulation and Cephalothorax Discoloration in Pandalus borealis: A Food Safety Concern

Abstract

Pandalus borealis, commonly found in the cold North Atlantic and Arctic oceans, has been observed to exhibit seasonal discoloration of the cephalothorax. This study investigates whether this discoloration correlates with cadmium bioaccumulation, a heavy metal pollutant introduced into marine environments through both natural and anthropogenic sources. Using atomic absorption spectrophotometry (AAS), cadmium concentrations were measured in 62 composite shrimp samples (31 pink-headed and 31 discolored). Concentrations in pink samples ranged from 2.484 to 10.895 mg/kg (relative standard deviation 30%), while discolored samples ranged from 2.405 to 6.901 mg/kg (RSD 20%). Normality tests (p = 0.073 for pink, p = 0.088 for discolored) indicated non-normal data distribution, prompting the use of the non-parametric Mann-Whitney U test. Statistical analysis revealed no significant difference in cadmium concentrations between the two groups (p = 0.3983). These results indicate that cadmium bioaccumulation is not a primary contributor to cephalothorax discoloration in P. borealis. Given the overlapping concentration ranges and high variability, further research is recommended to investigate other contributing factors such as additional trace metals, microbial infections, age, and exposure duration. The study implies the need for a multifactorial approach to understanding discoloration and potential food safety risks in marine species.