Morphological deformities and recovery, accumulation and elimination of lead in body tissues of Chinese sturgeon, Acipenser sinensis, early life stages: a laboratory study

Abstract

To determine the teratogenic effects of lead (Pb) on young Chinese sturgeon (A. sinensis), fertilized eggs (96-h) were exposed to Pb2+ until juvenile stages (total exposure 112 days). Three nominal concentrations were employed: 0.2 mg L−1, 0.8 mg L−1 and 1.6 mg L−1. After the exposure period, juveniles were returned to Pb-free water for a subsequent 42 days depuration period. Fish exposed to 0.8 and 1.6 mg L−1 Pb2+ exhibited body deformities during the exposure phase, appearing mainly as curvatures to left or right at OD (Origin of dorsal fin) to OC (Origin of the dorsal caudal fin), and OC to PC (Posterior margin of caudal fin) as well as to the OP (Origin of pectoral fin), associated with ptosis at PC. Moreover, the higher the concentration of water-borne Pb, the sooner body deformations occurred, while also affecting a larger proportion of the test individuals. Free locomotion and effective foraging was greatly reduced with increasing body deformation (lordosis). Pb accumulation in tissues was concentration dependent. Muscles accumulated relatively higher Pb which may have contributed to its effect on the muscle contraction potential and thus may have effected the neuromuscular system (muscle-induced body curvature). Morphological recovery decreased during the depuration period and this was accompanied by declining tissue Pb concentrations, indicating some self-repairing capacity.