Comparing the Sensitivity of Algal, Cyanobacterial and Bacterial Bioassays to Different Groups of Antibiotics

Comparing the sensitivity of algal, cyanobacterial and bacterial bioassays to different groups of antibiotics van der Grinten, E.; Pikkemaat, M.G.; van den Brandhof, E.J.; Stroomberg, G.J.; Kraak, M.H.S. Published in: Chemosphere DOI: 10.1016/j.chemosphere.2010.04.011 Link to publication Citation for published version (APA): van der Grinten, E., Pikkemaat, M. G., van den Brandhof, E. J., Stroomberg, G. J., & Kraak, M. H. S. (2010). Comparing the sensitivity of algal, cyanobacterial and bacterial bioassays to different groups of antibiotics. Chemosphere, 80(1), 1-6. https://doi.org/10.1016/j.chemosphere.2010.04.011 General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. a b s t r a c t Antibiotics may affect both primary producers and decomposers, potentially disrupting ecosystem processes. Hence, it is essential to assess the impact of antibiotics on aquatic ecosystems. The aim of the present study was therefore to evaluate the potential of a recently developed test for detecting antibiotics in animal tissue, the Nouws Antibiotic Test (NAT), as a sensitive bioassay to assess the effects of antibiotics in water. To this purpose, we determined the toxicity of sulphamethoxazole, trimethoprim, flumequine, tylosin, streptomycin, and oxytetracycline, using the NAT adapted for water exposure. The sensitivity of the NAT was compared to that of bioassays with bacteria (Microtox), cyanobacteria and green algae. In the Microtox test with Vibrio fischeri as test organism, no effects were observed for any of the test compounds. For three of the six antibiotics tested, the cyanobacteria were more vulnerable than the green algae when using photosynthetic efficiency as an endpoint. The lowest EC50 values for four out of six tested antibiotics were obtained using the NAT bacterial bioassay. The bacterial plate system responded to antibiotics at concentrations in the lg L À1 and lower mg L À1 range and, moreover, each plate proved to be specifically sensitive to the antibiotics group it was designed for. It is concluded that the NAT bioassay adapted for water exposure is a sensitive test to determine the presence of antibiotics in water. The ability of this test to distinguish five major antibiotic groups is a very strong additional value

Critical comments on the WHO-UNEP State of the Science of Endocrine Disrupting Chemicals – 2012

AbstractEarly in 2013, the World Health Organization (WHO) released a 2012 update to the 2002 State of the Science of Endocrine Disrupting Chemicals. Several significant concerns have been identified that raise questions about conclusions reached in this report regarding endocrine disruption. First, the report is not a state-of-the-science review and does not follow the 2002 WHO recommended weight-of-evidence approach. Second, endocrine disruption is often presumed to occur based on exposure or a potential mechanism despite a lack of evidence to show that chemicals are causally established as endocrine disruptors. Additionally, causation is often inferred by the presentation of a series of unrelated facts, which collectively do not demonstrate causation. Third, trends in disease incidence or prevalence are discussed without regard to known causes or risk factors; endocrine disruption is implicated as the reason for such trends in the absence of evidence. Fourth, dose and potency are ignored for most chemicals discussed. Finally, controversial topics (i.e., low dose effects, non-monotonic dose response) are presented in a one-sided manner and these topics are important to understanding endocrine disruption. Overall, the 2012 report does not provide a balanced perspective, nor does it accurately reflect the state of the science on endocrine disruption

Effects of experimental manipulations of salinity and maturation status on the physiological condition and mortality of homing adult sockeye salmon held in a laboratory.

ABSTRACT Relatively little is known about the physiological response and mortality consequences of the return of anadromous fish to freshwater (FW). We explored the consequences of the return to FW by collecting maturing sockeye salmon from the marine waters off the mouth of the Fraser River and holding ∼50 sockeye in each of five treatments: saltwater (SW; salinity p ppt), iso-osmotic water (ISO; 13 ppt), FW (0 ppt), SW ϩ 28 gonadotropin-releasing hormone (SW ϩ GnRH), and FW ϩ GnRH. Exogenous GnRH treatments were intended to accelerate maturation. Results demonstrate that gill Na ϩ ,K ϩ ATPase activity, sex steroid concentrations, and cortisol levels were highly responsive to experimental manipulations and followed predicted trajectories (i.e., FW ϩ GnRH sockeye were the most mature and FW adapted). There were few among-treatment differences in hematocrit and plasma concentrations of lactate, glucose, Na ϩ , Cl Ϫ , and plasma osmolality among sockeye that survived to the end of treatments, indicating that sockeye rigorously maintain internal homeostatic conditions while alive. There were large among-treatment differences in mortality ( ), and each SW ϩ GnRH 1 SW 1 FW ϩ GnRH 1 FW p ISO treatment experienced a notable increase in mortality rate around the fifth day of treatment. Our results indicate that salinity represented a modestly larger challenge to the experimental sockeye than did the artificially accelerated sexual maturation. Our results also suggest that maturing sockeye either successfully acclimate to FW within 5 d of exposure or perish. These findings are consistent with the predictions of the theory of anadromy, in suggesting that the return of adults to FW can be physiologically challenging and can represent a period of significant natural mortality

Effects of endocrine disrupting chemicals on gonad development: Mechanistic insights from fish and mammals

Over the past century, evidence has emerged that endocrine disrupting chemicals (EDCs) have an impact on reproductive health. An increased frequency of reproductive disorders has been observed worldwide in both wildlife and humans that is correlated with accidental exposures to EDCs and their increased production. Epidemiological and experimental studies have highlighted the consequences of early exposures and the existence of key windows of sensitivity during development. Such early in life exposures can have an immediate impact on gonadal and reproductive tract development, as well as on long-term reproductive health in both males and females. Traditionally, EDCs were thought to exert their effects by modifying the endocrine pathways controlling reproduction. Advances in knowledge of the mechanisms regulating sex determination, differentiation and gonadal development in fish and rodents have led to a better understanding of the molecular mechanisms underlying the effects of early exposure to EDCs on reproduction. In this manuscript, we review the key developmental stages sensitive to EDCs and the state of knowledge on the mechanisms by which model EDCs affect these processes, based on the roadmap of gonad development specific to fish and mammals.The authors are grateful to the Intersectoral Centre for Endocrine Disruptor Analysis (ICEDA)'s researcher network that facilitated this Special Issue. LNM was supported by a H2020-Marie Skłodowska-Curie Action MSCA-IF-RI- 2017 awarded by the European Commission (ref. 797725-EpiSTOX).With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe

Exposure to a Brazilian pulp mill effluent impacts the testis and liver in the zebrafish

While many studies have shown that pulp mill effluents can affect ovarian physiology in fish, far fewer studies have considered the effects in males. We conducted a lab study to examine the effects of effluent from a Brazilian pulp and paper mill on hepatic and testicular morphology and various aspects of testicular physiology in the zebrafish Danio rerio. Males were exposed to lab water (control) or 4% effluent for 14 days. Effluent exposure did not affect testis size as measured by the gonadosomatic index, but contributed to morphological changes in the seminiferous tubules. The number of cysts with histopathological changes was elevated in effluent-exposed fish and the number of cysts containing spermatids was significantly reduced. The testis of effluent exposed fish had reduced levels of lactate, elevated lactate dehydrogenase activity, increased levels of reactive oxygen species and reduced levels of phosphorylated P38 mitogen-activated protein kinase (pP38 MAPK). Separate studies showed that the addition of lactate to testicular tissue incubated in vitro increased the activation of P38 MAPK. Effluent exposure also increased vacuolization, necrosis, apoptosis, hyperemia, and fat infiltration of the hepatocytes. Collectively, we provide evidence of short term effects of pulp mill effluent on testicular and hepatic physiology and biochemistry in the zebrafish

The influence of implantation techniques on lesion oriented-outcomes in Absorb BVS and Xience EES lesions treated in routine clinical practice at complete three year follow-up: AIDA trial QCA substudy

It has been hypothesized that dedicated optimized Absorb BVS implantation techniques might mitigate the risk of adverse events such as target vessel

Tilapia male urinary pheromone stimulates female reproductive axis

Mozambique tilapia males congregate in leks where they establish dominance hierarchies and attract females to spawn in sandy pits. Dominant males store more urine than subordinates and the pattern of urination and the high sensitivity of females to male urine suggest chemical signalling via the urine. Here we show that pre-ovulated and post-spawn females when exposed to dominant male urine increased significantly, in less than 1 h, the release rate of the maturation-inducing steroid 17,20bdihydroxypregn- 4-en-3-one which is maintained elevated for at least 6 h. This indicates a pheromonal role for male urine in the synchronisation of spawning. Furthermore, we show that the lack of affinity of 17,20bP to sex steroid binding globulin explains, at least partly, its rapid release and lack of detection in the blood. Thus tilapia urine involvement in several communication processes confirms that cichlids have evolved a sophisticated chemical signalling system together with their complex visual, acoustic and behavioural displays