Roussel Hélène, Joachim Sandrine, Lamothe Sylvain, Palluel Olivier, Gauthier Laury, Bonzom Jean-Marc
Ecotoxicological Risk Assessment Unit, INERIS, Parc technologique ALATA, 60550 Verneuil-en-Halatte, France.
Aquat Toxicol. 2007 May 31;82(4):272-80. doi: 10.1016/j.aquatox.2007.02.018. Epub 2007 Mar 4.
Three-spined stickleback (Gasterosteus aculeatus) was used as the highest trophic level predator in an outdoor mesocosm study assessing the effect of environmentally realistic copper concentration (0, 5, 25 and 75 microgL(-1)) over 18 months of continuous exposure. Condition factor, organosomatic indices (HIS, GSI and SSI) as well as copper bioaccumulation in the liver were measured at 15 days, 2, 4, 6, 10, 14 and 18 months after the beginning of the contamination. Population monitoring was realised after 6 and 18 months of contamination, allowing two reproduction periods to be measured. Results showed that condition factor was affected at medium and high copper concentrations and HSI was sporadically affected in all copper exposure, depending on the sex of the fish. GSI did not show any significant differences and SSI was lowered in the medium and high copper levels. Bioaccumulation was significantly different in males and females and fluctuated with season. A negative correlation was observed between copper bioaccumulation in the liver and fish size and a positive correlation with nominal copper concentration in the water was found. There was a negative correlation between condition factor, organosomatic indices and bioaccumulation in the liver. Population monitoring showed a significantly higher fish mean length after 6 months and a higher abundance after 18 months of exposure at the highest copper level. We conclude that indirect effects such as food and habitat availability or lower predation pressure on eggs and juveniles might have led to higher stickleback population abundances at the highest copper level. This highlights the need to study all the trophic levels when monitoring ecosystem health. Considering the population and the individual responses after 18 months of copper exposure, the NOEC for three-spined sticklebacks was 25 microgL(-1) (or 20 microgL(-1) if we consider the average effective concentration), with a LOEC of 75 microgL(-1) (or 57 microgL(-1), AEC).
在一项室外中宇宙研究中，三刺鱼（Gasterosteus aculeatus）被用作最高营养级捕食者，该研究评估了环境现实浓度的铜（0、5、25和75微克/升）在18个月连续暴露期间的影响。在污染开始后的第15天、2、4、6、10、14和18个月，测量了状况因子、器官体指数（肝体指数、性腺体指数和脾体指数）以及肝脏中的铜生物积累。在污染6个月和18个月后进行了种群监测，从而能够测量两个繁殖期。结果表明，在中等和高铜浓度下，状况因子受到影响，并且在所有铜暴露情况下，肝体指数都偶尔受到影响，这取决于鱼的性别。性腺体指数没有显示出任何显著差异，在中等和高铜水平下，脾体指数降低。雄性和雌性的生物积累存在显著差异，并且随季节波动。在肝脏中的铜生物积累与鱼的大小之间观察到负相关，并且发现与水中的名义铜浓度呈正相关。状况因子、器官体指数与肝脏中的生物积累之间存在负相关。种群监测表明，在最高铜水平下暴露6个月后，鱼的平均长度显著更高，暴露18个月后丰度更高。我们得出结论，诸如食物和栖息地可用性或对卵和幼鱼的较低捕食压力等间接影响可能导致在最高铜水平下三刺鱼种群丰度更高。这突出了在监测生态系统健康时研究所有营养级的必要性。考虑到铜暴露18个月后的种群和个体反应，三刺鱼的无观测效应浓度为25微克/升（如果我们考虑平均有效浓度则为20微克/升），最低观测效应浓度为75微克/升（或57微克/升，平均有效浓度）。
