Andersen Tobias Henrik, Tjørnhøj Rikke, Wollenberger Leah, Slothuus Tina, Baun Anders
Institute of Environment and Resources, Building 115, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Environ Toxicol Chem. 2006 May;25(5):1187-95. doi: 10.1897/05-465r1.1.
Short-term (<48 h) and long-term (21 d) effects of dimethoate and pirimicarb were studied in Daphnia magna exposed to pulses of 0.5 to 8 h in duration. During a 21-d postexposure observation period, the following parameters were monitored: Mortality, mobility, day for first offspring, animal size, weight of offspring and adults, and number of offspring produced. In general, animals exposed to a single pulse of dimethoate or pirimicarb regained mobility after 24 to 48 h in clean media. Animals exposed to repeated pulses of dimethoate did not recover mobility during a 48-h postexposure observation period, and mortality was significantly increased. Animals exposed to two pulses of pirimicarb showed less recovery of mobility compared with those exposed to one pulse. Exposure of D. magna to 30 mg/L of dimethoate or 100 microg/L of pirimicarb for 2 to 6 h resulted in a significant reduction in the number of offspring and in the average weight of offspring. The average body length was reduced after pulse exposure to 30 mg/L of dimethoate for 3 h or 70 microg/L of pirimicarb for 4 h, and these exposure concentrations caused a delay in the day for first offspring at exposure durations of 2 to 6 h. The most important new findings in the present study are that short-term (<4 h) pulse exposure of neonates to acetylcholinesterase-inhibiting pesticides caused reproductive damage in D. magna and that repeated-pulse exposure significantly increased mortality in animals that apparently had recovered after a single-pulse exposure.
研究了乐果和抗蚜威对大型溞的短期（<48小时）和长期（21天）影响，大型溞暴露于持续时间为0.5至8小时的脉冲中。在21天的暴露后观察期内，监测了以下参数：死亡率、活动能力、首次产幼的天数、动物大小、幼体和成体的重量以及产幼数量。一般来说，暴露于单次乐果或抗蚜威脉冲的动物在清洁培养基中24至48小时后恢复了活动能力。暴露于乐果重复脉冲的动物在暴露后48小时的观察期内未恢复活动能力，且死亡率显著增加。与暴露于一次脉冲的动物相比，暴露于两次抗蚜威脉冲的动物活动能力恢复较少。大型溞暴露于30毫克/升的乐果或100微克/升的抗蚜威2至6小时，导致幼体数量和幼体平均重量显著减少。脉冲暴露于30毫克/升的乐果3小时或70微克/升的抗蚜威4小时后，平均体长减小，并且在暴露持续时间为2至6小时时，这些暴露浓度导致首次产幼的天数延迟。本研究中最重要的新发现是，新生儿短期（<4小时）脉冲暴露于抑制乙酰胆碱酯酶的农药会对大型溞造成生殖损害，并且重复脉冲暴露会显著增加在单次脉冲暴露后明显恢复的动物的死亡率。
