>Experiments with mice, rats, and dogs[42] have shown that a degree of 25% deuteration causes (sometimes irreversible) sterility, because neither gametes nor zygotes can develop. High concentrations of heavy water (90%) rapidly kill fish, tadpoles, flatworms, and Drosophila. The only known exception is the anhydrobiotic nematode Panagrolaimus superbus, which is able to survive and reproduce in 99.9% D2O.[40] Mammals (for example, rats) given heavy water to drink die after a week, at a time when their body water approaches about 50% deuteration.[43] The mode of death appears to be the same as that in cytotoxic poisoning (such as chemotherapy) or in acute radiation syndrome (though deuterium is not radioactive)
>Experiments with mice, rats, and dogs[42] have shown that a degree of 25% deuteration causes (sometimes irreversible) sterility, because neither gametes nor zygotes can develop. High concentrations of heavy water (90%) rapidly kill fish, tadpoles, flatworms, and Drosophila. The only known exception is the anhydrobiotic nematode Panagrolaimus superbus, which is able to survive and reproduce in 99.9% D2O.[40] Mammals (for example, rats) given heavy water to drink die after a week, at a time when their body water approaches about 50% deuteration.[43] The mode of death appears to be the same as that in cytotoxic poisoning (such as chemotherapy) or in acute radiation syndrome (though deuterium is not radioactive)