Lead and cadmium distribution and translocation in cultivated Coprinus comatus from heavy metal-controlled experiment: Health implications for human consumption

comatus is an important functional food, and lead (Pb) and cadmium (Cd) are common toxic elements that threaten food safety. However, the accumulation behavior of these metals and their effects on C. comatus growth remain poorly understood. This study investigated the effects of Pb and Cd on the growth of C. comatus and their bioaccumulation characteristics in the mushroom through inhibition experiments. Our results indicate that heavy metal stress affects mycelial growth, with the maximum tolerance concentration for Pb exceeding 1000 mg L -1 and for Cd being 50 mg L -1 . Pb and Cd stress also reduced agronomic traits (AT) and biological efficiency (BE) of C. comatus , with Cd exerting a greater inhibitory effect. Under 5 mg kg -1 Cd stress, the height (PH), pileus length (PL), diameter (PD), stipe length (SL), diameter (SD), and BE decreased by 32.98, 29.73, 29.03, 44.21, 24.58, and 30.78%, respectively, compared to the control (TCK). The pileus exhibited a stronger bioaccumulation capacity than the stipe, with peak levels observed under 300 mg kg -1 Pb and 5 mg kg -1 Cd stress, where pileus concentrations were 2.77 and 2.35 times those of the stipe, respectively. Based on target hazard quotients (THQs), C. comatus may pose potential human health risks when the concentrations of Pb and Cd in the substrate exceed 100 and 0.2 mg kg -1 dw, respectively. This study clarifies the effects of Pb and Cd on C. comatus growth and yield, establishing safe production thresholds and emphasizing the need for Cd pollution control in cultivation. • Maximum tolerance concentration of Pb and Cd in C. comatus mycelia was elucidated. • The biological efficiency of C. comatus was significantly decreased with Cd stress. • Pb and Cd accumulated mainly in the pileus of C. comatus. • Accumulation capability of Cd in C. comatus was stronger than that of Pb. • Pb and Cd concentrations in substrate should be <100 and 0.2 mg kg -1 dw, respectively.