Steroidal estrogens, originating principally from human excretion, are likely to play a major role in causing widespread endocrine disruption in wild populations of the roach (Rutilus rutilus), a common cyprinid fish, in rivers contaminated by treated sewage effluents. Given the extent of this problem, risk assessment models are needed to predict the location and severity of endocrine disruption in river catchments and to identify areas where regulation of sewage discharges to remove these contaminants is necessary. In this study we attempted to correlate the extent of endocrine disruption in roach in British rivers, with their predicted exposure to steroid estrogens derived from the human population. The predictions of steroid estrogen exposure at each river site were determined by combining the modeled concentrations of the individual steroid estrogens [17β -estradiol (E2), estrone (E1), and 17α -ethinylestradiol (EE2)] in each sewage effluent with their predicted dilution in the immediate receiving water. This model was applied to 45 sites on 39 rivers throughout the United Kingdom. Each site studied was then categorized as either high, medium, or low “risk” on the basis of the assumed additive potency of the three steroid estrogens calculated from data derived from published studies in various cyprinid fish species. We sampled 1,438 wild roach from the predicted high-, medium-, and low-risk river sites and examined them for evidence and severity of endocrine disruption. Both the incidence and the severity of intersex in wild roach were significantly correlated with the predicted concentrations of the natural estrogens (E1 and E2) and the synthetic contraceptive pill estrogen (EE2) present. Predicted steroid estrogen exposure was, however, less well correlated with the plasma vitellogenin concentration measured in the same fish. Moreover, we found no correlation between any of the end points measured in the roach and the proportion of industrial effluents entering the rivers we studied. Overall, our results provide further and substantive evidence to support the hypothesis that steroidal estrogens play a major role in causing intersex in wild freshwater fish in rivers in the United Kingdom and clearly show that the location and severity of these endocrine-disrupting effects can be predicted.

This review provides a critical analysis of the biological effects of the most widely used plasticizers, including dibutyl phthalate, diethylhexyl phthalate, dimethyl phthalate, butyl benzyl phthalate and bisphenol A (BPA), on wildlife, with a focus on annelids (both aquatic and terrestrial), molluscs, crustaceans, insects, fish and amphibians. Moreover, the paper provides novel data on the biological effects of some of these plasticizers in invertebrates, fish and amphibians. Phthalates and BPA have been shown to affect reproduction in all studied animal groups, to impair development in crustaceans and amphibians and to induce genetic aberrations. Molluscs, crustaceans and amphibians appear to be especially sensitive to these compounds, and biological effects are observed at environmentally relevant exposures in the low ng l 21 to mg l 21 range. In contrast, most effects in fish (except for disturbance in spermatogenesis) occur at higher concentrations. Most plasticizers appear to act by interfering with the functioning of various hormone systems, but some phthalates have wider pathways of disruption. Effect concentrations of plasticizers in laboratory experiments coincide with measured environmental concentrations, and thus there is a very real potential for effects of these chemicals on some wildlife populations. The most striking gaps in our current knowledge on the impacts of plasticizers on wildlife are the lack of data for long-term exposures to environmentally relevant concentrations and their ecotoxicity when part of complex mixtures. Furthermore, the hazard of plasticizers has been investigated in annelids, molluscs and arthropods only, and given the sensitivity of some invertebrates, effects assessments are warranted in other invertebrate phyla.

Aquaculture is the fastest growing farmed food sector and will soon become the primary source of fish and shellfish for human diets. In contrast to crops and livestock, production is derived from numerous, exceptionally diverse species that are typically in the early stages of domestication. Genetic improvement of production traits via well-designed, managed breeding programmes has great potential to help meet the rising seafood demand driven by human population growth. Supported by continuous advances in sequencing and bioinformatics, genomics is increasingly being applied across the broad range of aquaculture species and at all stages of the domestication process to optimize selective breeding. In the future, combining genomic selection with biotechnological innovations, such as genome editing and surrogate broodstock technologies, may further expedite genetic improvement in aquaculture.

Despite increasing application of silver nanoparticles (NPs) in industry and consumer products, there is still little known about their potential toxicity, particularly to organisms in aquatic environments. To investigate the fate and effects of silver NPs in fish, rainbow trout (Oncorhynchus mykiss) were exposed via the water to commercial silver particles of three nominal sizes: 10 nm (N(10)), 35 nm (N(35)), and 600-1600 nm (N(Bulk)), and to silver nitrate for 10 days. Uptake into the gills, liver, and kidneys was quantified by inductively coupled plasma-optical emission spectrometry, and levels of lipid peroxidation in gills, liver, and blood were determined by measurements of thiobarbituric acid reactive substances. Expression of a suite of genes, namely cyp1a2, cyp3a45, hsp70a, gpx, and g6pd, known to be involved in a range of toxicological response to xenobiotics was analyzed in the gills and liver using real-time PCR. Uptake of silver particles from the water into the tissues of exposed fish was low but nevertheless occurred for current estimated environmental exposures. Of the silver particles tested, N(10) were found to be the most highly concentrated within gill tissues and N(10) and N(Bulk) were the most highly concentrated in liver. There were no effects on lipid peroxidation in any of the tissues analyzed for any of the silver particles tested, and this is likely due to the low uptake rates. However, exposure to N(10) particles was found to induce expression of cyp1a2 in the gills, suggesting a possible increase in oxidative metabolism in this tissue.

Surges of luteinizing hormone (LH) that result in luteinization but occur prematurely with respect to the diameter of the leading follicle, prevent attempts to induce multiple follicular maturation for in-vitro fertilization (IVF) in a significant number of women. We examined the possibility of blocking premature LH surges by the administration of Cetrorelix, a potent antagonist of gonadotrophin-releasing hormone (GnRH), in a study including 20 patients, some of whom had previously shown premature LH surges. All patients were treated with human menopausal gonadotrophins (HMG) starting on day 2. From day 7 until the induction of ovulation by human chorionic gonadotrophin (HCG) the GnRH antagonist Cetrorelix was given daily. HCG was injected when the dominant follicle had reached a diameter of > or = 18 mm and oestradiol concentration was > 300 pg/ml for each follicle having a diameter of > 15 mm. Oocyte collection was performed 36 h later by transvaginal ultrasound puncture, followed by IVF and embryo transfer. The hormone profiles of these patients and the results of IVF and embryo transfer are comparable to those treated with GnRH agonists and HMG. However, less time and especially less HMG is needed in comparison to patients stimulated with a long agonist protocol. Hence, treatment with Cetrorelix proved to be much more comfortable for the patient. In this study we showed that combined treatment with gonadotrophins and the GnRH antagonist Cetrorelix is a promising method for ovarian stimulation in patients who frequently exhibit premature LH surges and therefore fail to complete treatment.

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Silver nanoparticles cause toxicity in exposed organisms and are an environmental health concern. The mechanisms of silver nanoparticle toxicity, however, remain unclear. We examined the effects of exposure to silver in nano-, bulk-, and ionic forms on zebrafish embryos (Danio rerio) using a Next Generation Sequencing approach in an Illumina platform (High-Throughput SuperSAGE). Significant alterations in gene expression were found for all treatments and many of the gene pathways affected, most notably those associated with oxidative phosphorylation and protein synthesis, overlapped strongly between the three treatments indicating similar mechanisms of toxicity for the three forms of silver studied. Changes in oxidative phosphorylation indicated a down-regulation of this pathway at 24 h of exposure, but with a recovery at 48 h. This finding was consistent with a dose-dependent decrease in oxygen consumption at 24 h, but not at 48 h, following exposure to silver ions. Overall, our data provide support for the hypothesis that the toxicity caused by silver nanoparticles is principally associated with bioavailable silver ions in exposed zebrafish embryos. These findings are important in the evaluation of the risk that silver particles may pose to exposed vertebrate organisms.

Aquaculture is predicted to supply the majority of aquatic dietary protein by 2050. For aquaculture to deliver significantly enhanced volumes of food in a sustainable manner, appropriate account needs to be taken of its impacts on environmental integrity, farmed organism health and welfare and human health. Here, we explore increased aquaculture production through the One Health lens and define a set of success metrics -underpinned by evidence, policy and legislation -that must be embedded into aquaculture sustainability. We provide a framework for defining, monitoring and averting potential negative impacts of enhanced production -and consider interactions with landbased food systems. These metrics will inform national and international science and policy strategies to support improved aquatic food system design. MAINAquaculture is one of the fastest growing and highly traded food sectors globally -Asia accounts for 90% of production [1] and volumes are predicted to double by 2050 [1] (Supplement 1). Enhanced sustainable production (ESP) in aquaculture features within the Rome Declaration of the 2 nd International Conference on Nutrition (ICN2), the United Nations Framework Convention on Climate Change (COP21) and in the 2030 Agenda for Sustainable Development [2]. Achieving ESP is technically, socially and politically complex: the sector spans small homestead-scale production systems -underpinning food security in rural settings in low-and middle-income counties (LMICs)to medium sized farms that contribute to exports and high-technology industrial-scale production of globally traded products. More than 500 aquatic species are farmed in widely divergent social and legislative infrastructures -with different end goals. Thus, a holistic approach to the design and implementation of aquaculture systems is needed [3] -framed within the broader context of sustainable food systems [4].The sector offers many positive aspects: poverty alleviation in some of the lowest income regions [5], production increases from technological advances and selected species lines[6], the use of non-fed (e.g. molluscs) and extractive species (e.g. seaweed) [7] with benefits of farms for proximate marine biodiversity [8], comparatively lower environmental impact of some types of aquaculture [9,10] and smaller spatial footprints compared with both capture fisheries [11,12] and land-based agriculture [13]. However, numerous sustainability challenges must be addressed across the diverse range of aquaculture sectors. For example, economic gains in the global shrimp sector have been prioritised in spite of evidence of major mangrove forest degradation [14], bonded labour and social inequities [15], and potentially high carbon footprints [16,17]. The profitable northern hemisphere Atlantic