Effects of Anthropogenic Estrogens Nonylphenol and 17?-Ethinylestradiol in Aquatic Model Ecosystems

Abstract

Microcosm tests were conducted to investigate the effects of the estrogenic substances nonylphenol (NP) and 17α‐ethinylestradiol (EE) on aquatic ecosystems. Maximum concentrations of 9 to 120 μg L—1 NP resp. 49 to 724 ng L—1 EE were induced by controlled release. The controlled release method allows the establishment of a continuous concentration course. The microcosms proved to run robustly with abiotic conditions close to natural. They developed biocenosis with similar characteristics as in natural ecosystems and, considering their given level of complexity, they can be used to describe possible risks for the environment. Both tested chemicals unveiled the potential to affect the plankton communities in the tested concentration range. NP exposure caused a reduction of Cladocera and Copepoda abundances and disturbed the phytoplankton structure. A NOECcommunity of 30 μg L—1 was calculated. In the first EE study, a flood in the lake where the microcosm water was collected caused additional stress and thereby a high variability, both between the microcosms and in each microcosm over time. Probably therefore the only effect found was a reduction of Copepoda abundance. In a second EE study Cladocera and Copepoda abundances were reduced, from which the phytoplankton benefited. Although a final interpretation is difficult for results of microcosm tests, there are indications that the found effects of EE and perhaps also NP may be caused at least partially by endocrine disruptive activity.

Elevated Concentrations of Ethinylestradiol, 17β-Estradiol, and Medroxyprogesterone have Little Effect on Reproduction and Survival of Ceriodaphnia dubia

“…Thus it will be important to verify that these effects occur at environmentally relevant concentrations and that they cause population level changes in aquatic crustaceans. Recent mesocosm studies suggest that exposure to environmentally realistic concentrations of either EE 2 or NP reduces the abundance of cladocerans and copepods (Hense et al 2005). It will also be important to understand the differences in sensitivity among different invertebrate species.…”

Effects of 4-nonylphenol, fish predation and food availability on survival and life history traits of Daphnia magna straus

“…NP has toxic effects (Burkhardt-Holm et al 2000;Hughes et al 2000) possibly because of its strong surfactant properties (Hense et al 2005). Reduction of survival upon exposure to NP may be the manifestation of the toxic effect of NP and can possibly be due to the altered energy budget of the test organisms (Weltje et al 2005).…”

“…It is known that NP mimics the action of the female hormone estrogen in vertebrates (Jobling et al 1996;Christiansen et al 1998;Cakmak et al 2003Cakmak et al , 2006Hense et al 2005). Then again, the endocrine systems of many invertebrates are still not fully characterized (Gourmelon and Ahtiainen 2007;Tatarazako and Oda 2007).…”

“…NP has toxic (Burkhardt-Holm et al 2000;Hughes et al 2000), carcinogenic (Blom et al 1998;Skakkebaek et al 1998), and histopathological (Uguz et al 2003) effects on various organisms. Moreover, it has been reported to be an endocrine disrupter, which mimics the action of the female hormone estrogen, in vertebratesespecially fish (Jobling et al 1996;Christiansen et al 1998;Cakmak et al 2003Cakmak et al , 2006Hense et al 2005). Although the lack of estrogen receptors in crustaceans-major aquatic invertebrates-naturally weakens the estrogenic effect of NP, it nevertheless has been proven to interfere with ecdysteroid signalling, a major pathway regulating various aspects of growth, reproduction and metabolism (LeBlanc 2007).…”

Direct and indirect responses of a freshwater food web to a potent synthetic oestrogen

“…Typically, responses in invertebrates are seen only at comparatively high concentrations (microgram per litre to milligram per litre levels), although decreased abundance of adult copepods and cyclopoids and enzyme activities can occur at concentrations of EE2 as low as 10 ng l 21 [24]. Few studies have examined whether invertebrate community structure is affected by EE2 or other oestrogens [26], and the long-term effects of oestrogen exposure on wild populations of zooplankton and benthic invertebrate populations and communities are unknown. EDCs may affect aquatic invertebrates not only through direct toxic impacts but also by indirect changes in food-web interactions such as predation or competition [27].…”