The joint toxicity of lead with cadmium and zinc was complicated: when the toxicity proportion of the three is 1:1:1, they are antagonism to each other; however, if their concentration proportion is 1:1:1, they are synergistic.

• 铅、镉和锌三者共存时的联合毒性较为复杂，三者浓度比1:1:1时表现为协同作用，而毒性比1:1:1时表现为拮抗作用。