Abstract: By using static test method, this paper studied the single and joint toxicities of SDS and Cd²⁺ on adult Procambarus clarkii. For SDS, its 24, 48, 72, and 96 h 50% lethal concentration (LC₅₀) and its safety concentration (SC) were 1365.60, 1171.72, 1128.43, 1120.43, and 258.79 mg·L^-1, respectively. For Cd²⁺, the corresponding values were 1197.09, 142.06, 90.85, 82.64, and 0.6 mg·L^-1, respectively. SDS had a lower toxicity while Cd²⁺ had a higher toxicity to P. clarkia. When the toxicity ratio of SDS and Cd²⁺ was 1:1 and the exposure time was 24, 48, 72, and 96 h, the additive index (AI) was 0.335, 0.017, 0.030, and 0.032, respectively, indicating that the joint toxicity of SDS and Cd²⁺ was synergistic.

Key words: glucose, starch, BIOLOG, carbon metabolism, root function.