Hormone active agents constitute a dangerous class of pollutants. Among them, those agents that mimic the action of estrogens on target cells and are part of the group of endocrine-disruptor compounds (EDCs) are termed estrogenic EDCs, the main focus of this review. Exposure to these compounds causes a number of negative effects, including breast cancer, infertility and animal hermaphroditism. However, especially in underdeveloped countries, limited efforts have been made to warn people about this serious issue, explain the methods of minimizing exposure, and develop feasible and efficient mitigation strategies at different levels and in various environments. For instance, the use of bioremediation processes capable of transforming EDCs into environmentally friendly compounds has been little explored. A wide diversity of estrogen-degrading microorganisms could be used to develop such technologies, which include bioremediation processes for EDCs that could be implemented in biological filters for the post-treatment of wastewater effluent. This review describes problems associated with EDCs, primarily estrogenic EDCs, including exposure as well as the present status of understanding and the effects of natural and synthetic hormones and estrogenic EDCs on living organisms. We also describe potential biotechnological strategies for EDC biodegradation, and suggest novel treatment approaches for minimizing the persistence of EDCs in the environment.

We studied the bioaccumulation of metals and PAHs, the pathological conditions, regressive phenomena and pathogens in wild Mytilus galloprovincialis taken along the North Pier facing the former second Italian largest steelworks of Bagnoli. There was no Cd and Pb bioaccumulation with respect to the EU role 221/2002. Metal shell index decreased as follows: Pb > Ni > Zn > Cu and correlates with the pollution state. The level of BaP was up to thirtysixfold higher the EU rule 835/2011. The sum of 4 hydrocarbons, PAH4, were up to seventeen-fold the rule. PAH levels increased toward the coast. Prevalence values of tissue necrosis and inflammatory lesions were between 50 and 100%. In May animals showed lesion like granulocytomas and inflammatory capsules. Signs of atresia, necrotic oocytes and diffused cases of hermaphroditism were detected. An appropriate localization of farming to avoid contamination from sediment turbulence and risks for consumer health is needed.

The increasing availability of human-made structure in the oceans coupled with climate changes may lead to the range expansion of species able to disperse by rafting. In this study, we report on zoantharian species of genera Isaurus, Palythoa, Umimayanthus and Zoanthus covering artificial substrates in locations in both the Atlantic and Pacific oceans. Moreover, we reviewed observations of additional zoantharians as macrofouling organisms, and discuss the possible role of rafting in the dispersal of this cosmopolitan group. Traits reported to some zoantharian species, such as hermaphroditism and resistance to desiccation, support their dispersal potential by drifting attached to floating objects. Further reports of zoantharian species covering floating artificial structures and natural debris are needed to increase our knowledge of dispersal mechanisms in the oceans. Additionally, this information is essential to monitor and manage possible exotic species invasions, especially for zoantharian species that are common in the aquarium trade.

In order to assess the effects of increasing temperature on the reproductive performance of fish, different thermal conditions (i.e., 25.0, 26.5, 27.5, 28.5, 30.0 °C) were used in this study and the self-fertilizing hermaphrodite fish, Kryptolebias marmoratus, was exposed to these different thermal conditions. During an exposure period of 30 to 150 days, the gonadosomatic index (GSI), gonadal development, the levels of plasma 17β-estradial (E2) and testosterone (T), hepatic vitellogenin (VTG) mRNA abundance, and the number of self-fertilized eggs were analyzed. This study confirmed that a high water temperature above 27.5 °C led to the suppression of self-fertility of hermaphroditic fish from 30 days after exposure. The oocyte quality and maturation would be affected by the disruption of hepatic VTG synthesis at a high water temperature of 30 °C, which resulted in the reduced the self-fertility in K. marmoratus. Consequently, this study suggests that elevated water temperature due to aquatic climate change prior to sexual maturation and the onset of spawning can lead to the reproductive dysfunction of hermaphroditic K. marmoratus.

Margaritifera margaritifera is a critically endangered species in Europe. Among the causes explaining its decline, metal pollution had never been deeply studied. Thus, an ecotoxicological investigation was developed on this species which comes from the Dronne River (South-West of France). Cadmium (Cd) exposure of mussels at 2 and 5 μg/L for 7 days was conducted to test their vulnerability to this metal, and also the potential endocrine disruption power of Cd. Morphometric analyses, gonad histological observations, metal bioaccumulation, metallothionein (MTs) production, measures of malondialdehyde (MDA), and finally quantitative relative expression analysis of genes involved in various metabolic functions were performed.The main results showed Cd accumulation increasing in a dose-dependent manner, especially in the gills. The same trend was observed for gene expression relative to oxidative stress. Histological analysis of the gonads highlighted a predominance of hermaphrodite individuals, but after 7 days of exposure to Cd, the percentage of female was largely increased compared with controls, from 17 to 33%. These results demonstrate the endocrine disruption effect of Cd on freshwater pearl mussels.The pearl mussel Margaritifera margaritifera is sensitive to cadmium since the metallothioneins are poorly induced, gene expression reveals oxidative stress, and gonads tend to be feminized.

Oxyfluorfen (Goal 24%EC) herbicide is widely used in agriculture for weed control. Biomphalaria alexandrina snails can be used as bioindicator of the chemical pollution in the aquatic environment. The objective of this study was to evaluate the molluscicidal activity of this herbicide on Biomphalaria alexandrina snails and how it affected its biological system. The present study revealed a molluscicidal effect of oxyfluorfen 24%EC on these snails at LC₅₀ 5.9 mg/l. After exposure of snails to the sub-lethal concentrations (LC₀, LC₁₀, or LC₂₅) of this herbicide, the survival rates, reproductive rate (R₀), and fecundity (Mₓ) of adult B. alexandrina snails were significantly decreased in comparison with the control group. Also, levels of testosterone and estradiol were decreased significantly. It caused alterations in the antioxidant system, where exposure to sub-lethal concentration of this herbicide caused significant increases in levels of lipid peroxide malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD), while it significantly decreased glutathione transferase (GST). Histopathological changes in the digestive gland included severe damage in the digestive cells, where, they lost their tips and some were degenerated, while the secretory cells increased in number. Regarding the hermaphrodite gland, there were losses of the connective tissues, irregular sperms, and the eggs degenerated. These findings concluded that B. alexandrina snails can be used as a bioindicator for pollution with pesticide in the aquatic environment.

Schistosomiasis is one of the neglected tropical diseases. It is a snail-borne trematode infection, and Biomphalaria alexandrina snails are the intermediate host of Schistosoma mansoni in Egypt. The objective of this study is to evaluate the molluscicidal activity of the aqueous seed extract of Moringa oleifera against B. alexandrina snails. The results showed that this aqueous extract was lethal for B. alexandrina snails (LC₅₀ 0.27 g/l; LC₉₀ 0.41 g/l). Exposure of snails to the sublethal concentrations of this aqueous extract caused a considerable reduction in survival rates and hatchability rates of eggs of these snails. Moreover, it negatively affected some biochemical aspects, where it increased the levels of transaminases (ALT and AST), while it decreased the concentrations of total protein, albumin, and globulin concentration. Histological examinations of the digestive gland of snails exposed to the sublethal concentrations of aqueous seed extract of M. oleifera revealed severe damage in the digestive cells, where they lost their tips and some were degenerated, while the secretory cells increased in number. Regarding the hermaphrodite gland, there were losses of connective tissues and irregular sperms, and the eggs were degenerated. These findings prove the potent activity of aqueous seed extract of M. oleifera against the intermediate hosts of Schistosoma mansoni and provide a considerable scope in exploiting local indigenous resources for snails’ molluscicidal agents.