A negative correlation between mercury content in muscle and body weight in carp from uncontaminated ponds

The relationship between body weight and total mercury content in the muscle of common carp (Cyprinus carpio) from 13 uncontaminated ponds in South and West Bohemia was investigated. In total, 215 three-years-old marketable carps and 26 samples of bottom sediment were analysed. Total mercury contents (THg) in muscle and sediments were determined using an single-purpose atomic absorption spectrophotometer. The correlation between body weight and mercury content in muscle was found to be negative and statistically significant (Pearson correlation: rp = -0.269, P < 0.001). THg content in muscle significantly decreased as the body weight of carp from uncontaminated ponds increased. This is likely due to the intensive weight gain of marketable carp.