Estrogenic compounds affect development of harpacticoid copepod Tigriopus japonicus

Abstract

The aim of this investigation was to evaluate the impact of estrogenic compounds on the harpacticoid copepod Tigriopus japonicus after continuous exposure to environmentally relevant concentrations. Natural estrogen (17beta-estradiol), three known estrogenic compounds in vertebrates (bisphenol A, 4-nonylphenol, p-t-octylphenol), and an invertebrate molting hormone (20-hydroxyecdysone) were tested for their effects on development and reproductive characters in two successive generations of T. japonicus. Less than 24-h-old nauplii (parentals) were exposed to four sublethal concentrations of these compounds for 21 d at 25 degrees C. The first brood of nauplii (F1) produced was monitored further under the same culture conditions and exposures to test compounds. Results showed that all estrogenic compounds affected development (both in number of days to reach copepodid stage and sexual maturity) in the parental generation. Similar effects were apparent in the F1; however, fecundity, sex ratio, and survival were not significantly affected, even at concentrations as high as 10 microg/L (nominal concentration). The invertebrate molting hormone 20-hyroxyecdysone had no detectable effect on any of the endpoints tested but gave the lowest 48-h 50% lethal concentration (LC50) value. The results suggest that endocrine disruption could occur in copepods following exposure to environmentally relevant concentrations of estrogenic compounds, especially if they are exposed starting from embryonic development.

A critical analysis of the biological impacts of plasticizers on wildlife

“…, respectively (Andersen et al 2001;Marcial et al 2003). A significant stimulation of larval development in A. tonsa was, however, observed at 12.5-50 mg l 21 (Mariager 2001), which was also seen in our own experiments at 30 and 60 mg l…”

Effect of diazinon on life stages and resting egg hatchability of rotifer Brachionus plicatilis

“…Among asexual reproduction parameters, generation time or the time to release first neonate is the most sensitive resulting to an EC 50 of 1.24 mg/L (Table 2). Embryogenesis, the first stage of rotifer life cycle, is also known to be the most sensitive stage to toxicants in other zooplankters including daphnids (LeBlanc, et al, 2000) and copepods (Marcial et al, 2003).…”

Bisphenol A: Understanding Its Health Effects from the Studies Performed on Model Organisms

“…Study on freshwater insect Chironomus riparius showed that adult emergence times were signiicantly delayed on moderate BPA exposure [107]. Marcial et al (2003) and Wats et al [108,109] found that the marine copepod Tigriopus japonicus showed developmental inhibition at a very low concentration of BPA (0.1 mg/L). However, it is unclear if these efects have any long-term impacts in adult life.…”