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Time‐dependent toxicity in bioassays is usually explained in terms of uptake and elimination kinetics of the toxicant By comparing different species with essentially different accumulation kinetics, a firm test of this concept may be made This article compares the sensitivity of six soil arthropods, the collembolans Orchesella cincta and Tomocerus minor, the oribatid mite Platynothrus peltifer, the isopods Porcellio scaber and Oniscus asellus, and the diplopod Cylindroiulus britannicus, when exposed to cadmium in the food Survival was determined at various time intervals, accumulation of cadmium in the animals was measured at one time interval Kinetic based toxicity models were fitted to the data, and estimates were obtained for lethal body concentration, uptake rate constant, elimination rate constant, and ultimate LC50 Two different accumulation patterns could be discerned, these were correlated with time‐survival relationships One, species that have the possibility to eliminate cadmium will reach an equilibrium for the internal concentration and also an ultimate LC50 Two, species that are unable to eliminate cadmium but store it in the body will have an ultimate LC50 equal to zero For these species the time in which the lethal body concentration is reached is more important Taxonomically related species appeared to have comparable accumulation patterns, but lethal body concentrations differed It is concluded that knowledge of the accumulation pattern is indispensable for the evaluation of species' sensitivities to toxicants

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