scholarly journals Bioaccumulation And Biotransformation of BDE-47 Using Zebrafish Eleutheroembryos (Danio Rerio)

Author(s):  
Paloma De Oro-Carretero ◽  
Jon Sanz Landaluze

Abstract Polybrominated diphenyl ethers (PBDEs) industrially used as flame retardants are nowadays considered emerging pollutants as they are endocrine disrupting chemicals (EDCs), persistent in the environment, bioaccumulative and in addition, its hydroxylated (OH-BDEs) and methoxylated (MeO-BDEs) metabolites have similar ecotoxic properties. The aim of this work was to develop an analytical method to be applied in the study of the bioconcentration and biotransformation of BDE-47 due to its bioavailability, toxicity and high persistence and abundance in environmental samples, including humans. So, a dependable ultrasonic extraction process followed to dispersive SPE clean-up step and GC-MS-μECD detection has worked out for the determination of BDE-47 and its main biotransformation products (MeO-BDEs and OH-BDEs), considering the polarity difference. In addition, an alternative method to bioconcentration official guideline OECD 305, developed previously with zebrafish (Danio rerio) eleutheroembryos (i.e., hatched but not yet free feeding embryos) is used, reducing dramatically the animal suffering but also time and reagents. Bioconcentration factors (BCF) were calculated using first order one-compartment toxicokinetic model. The profiles found show rapid absorption in the first hours of larval development and great bioaccumulative with capacity, finding bioconcentration factors (BCF) of 6631 and 44210 at nominal concentrations of 10 and 1 μg·L-1 (< 1% LC50), respectively. Metabolization studies show increasing concentrations of the metabolites BDE-28, 2'-OH-BDE-28 and 5-MeO-BDE-47 throughout the exposure time. The results obtained show the feasibility of the method for bioaccumulation and opens the possibility of metabolic studies with zebrafish eleutheroembryos, which is a very underdeveloped field without official testing or regulation.

2016 ◽  
Vol 24 (3) ◽  
pp. 253-273 ◽  
Author(s):  
Eric Akortia ◽  
Jonathan O. Okonkwo ◽  
Mlindelwa Lupankwa ◽  
Shiloh D. Osae ◽  
Adegbenro P. Daso ◽  
...  

Polybrominated diphenyl ethers (PBDEs) are a group of organobromine compounds that are used as flame retardants in many commonly used products. Their presence has been confirmed in various environmental matrices. Their usage in numerous consumer products has lent credence to their ability to retard flammable gas formation, hence their ubiquitous nature in the environment. PBDEs have been described as endocrine disrupting chemicals because of their interference with the endocrine system function in fish and other terrestrial animals. In spite of the progress in research over the years on PBDEs, full understanding of the environmental behaviour and fate of this contaminant is still elusive. In this review, sources by which PBDEs enter the environment have been evaluated in conjunction with their levels, as well as their toxicity, and the transformation and transport of PBDEs in various environmental compartments. This provides a better understanding of the behaviour of these emerging environmental contaminants within the environment. While acknowledging the numerous studies that have been conducted on the environmental contamination by PBDEs, emerging issues and data gaps have been identified.


2013 ◽  
Vol 85 (8) ◽  
pp. 1611-1624 ◽  
Author(s):  
Evan S. Beach ◽  
Brian R. Weeks ◽  
Rebecca Stern ◽  
Paul T. Anastas

The plastics enterprise depends on a small number of commodity polymers to perform in diverse applications, requiring additives to produce desired properties and performance. Toxic effects and environmental persistence of certain additive chemicals impact the sustainability of the industry. Green chemistry has been and will continue to be applied to find solutions to these issues. This review focuses on alternatives to phthalate plasticizers and halogenated flame retardants, two categories that together account for a significant portion of the global additives market and the global dispersion of endocrine-disrupting chemicals. Small-molecule alternatives that exist in various stages of research and commercialization will be discussed, with emphasis on the use of renewable resources. The rise of biorefineries and new bio-based monomers may help overcome existing economic barriers to adoption of alternatives. Increasing the molecular weight of additives or covalently linking them to polymer backbones are two promising strategies for reducing both mobility and toxicity that will also be discussed. Finally, the design of new polymers that show desirable properties without the use of additives will be considered. The substances put forward as “green” alternatives have yet to receive the same level of scrutiny as diethylhexyl phthalate (DEHP, also known as dioctyl phthalate) or polybrominated diphenyl ethers (PBDEs). Cooperation between chemists, engineers, and the environmental health community will be critical to ensure the safety and sustainability of new technologies.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Morgan R. Peltier ◽  
Michael J. Fassett ◽  
Yuko Arita ◽  
Vicki Y. Chiu ◽  
Jiaxiao M. Shi ◽  
...  

Abstract Objectives Nearly 100% of North American women have detectable levels of flame retardants such as polybrominated diphenyl ethers (PBDEs) in their plasma. These molecules have structural homology to thyroid hormones and may function as endocrine disruptors. Thyroid dysfunction has previously been associated with increased risk for preterm birth. Therefore, we conducted a multi-center, case-cohort study to evaluate if high plasma concentrations of a common PBDE congener in the first trimester increases the risk of preterm birth and its subtypes. Methods Pregnant women were recruited at the onset of initiation of prenatal care at Kaiser-Permanente Southern California (KPSC)-West Los Angeles and KPSC-San Diego medical centers. Plasma samples from women whose pregnancies ended preterm and random subset of those delivering at term were assayed for PBDE-47 and thyroid-stimulating hormone (TSH) by immunoassay. Quartile cutoffs were calculated for the patients at term and used to determine if women with exposures in the 4th quartile are at increased risk for preterm birth using logistic regression. Results We found that high concentrations of PBDE-47 in the first trimester significantly increased the odds of both indicated (adjusted odds ratio, adjOR=2.35, 95% confidence interval [CI]: 1.31, 4.21) and spontaneous (adjOR=1.76, 95% CI: 1.02, 3.03) preterm birth. Regardless of pregnancy outcome, TSH concentrations did not differ between women with high and low concentrations of PBDE-47. Conclusions These results suggest that high plasma concentrations of PBDE-47 in the first trimester, increases the risk of indicated and spontaneous preterm birth.


Toxics ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 14
Author(s):  
Mathilda Alsen ◽  
Catherine Sinclair ◽  
Peter Cooke ◽  
Kimia Ziadkhanpour ◽  
Eric Genden ◽  
...  

Endocrine disruptive chemicals (EDC) are known to alter thyroid function and have been associated with increased risk of certain cancers. The present study aims to provide a comprehensive overview of available studies on the association between EDC exposure and thyroid cancer. Relevant studies were identified via a literature search in the National Library of Medicine and National Institutes of Health PubMed as well as a review of reference lists of all retrieved articles and of previously published relevant reviews. Overall, the current literature suggests that exposure to certain congeners of flame retardants, polychlorinated biphenyls (PCBs), and phthalates as well as certain pesticides may potentially be associated with an increased risk of thyroid cancer. However, future research is urgently needed to evaluate the different EDCs and their potential carcinogenic effect on the thyroid gland in humans as most EDCs have been studied sporadically and results are not consistent.


Author(s):  
Jördis Klose ◽  
Melanie Pahl ◽  
Kristina Bartmann ◽  
Farina Bendt ◽  
Jonathan Blum ◽  
...  

AbstractDue to their neurodevelopmental toxicity, flame retardants (FRs) like polybrominated diphenyl ethers are banned from the market and replaced by alternative FRs, like organophosphorus FRs, that have mostly unknown toxicological profiles. To study their neurodevelopmental toxicity, we evaluated the hazard of several FRs including phased-out polybrominated FRs and organophosphorus FRs: 2,2′,4,4′-tetrabromodiphenylether (BDE-47), 2,2′,4,4′,5-pentabromodiphenylether (BDE-99), tetrabromobisphenol A, triphenyl phosphate, tris(2-butoxyethyl) phosphate and its metabolite bis-(2-butoxyethyl) phosphate, isodecyl diphenyl phosphate, triphenyl isopropylated phosphate, tricresyl phosphate, tris(1,3-dichloro-2-propyl) phosphate, tert-butylphenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, tris(1-chloroisopropyl) phosphate, and tris(2-chloroethyl) phosphate. Therefore, we used a human cell–based developmental neurotoxicity (DNT) in vitro battery covering a large variety of neurodevelopmental endpoints. Potency according to the respective most sensitive benchmark concentration (BMC) across the battery ranked from <1 μM (5 FRs), 1<10 μM (7 FRs) to the >10 μM range (3 FRs). Evaluation of the data with the ToxPi tool revealed a distinct ranking (a) than with the BMC and (b) compared to the ToxCast data, suggesting that DNT hazard of these FRs is not well predicted by ToxCast assays. Extrapolating the DNT in vitro battery BMCs to human FR exposure via breast milk suggests low risk for individual compounds. However, it raises a potential concern for real-life mixture exposure, especially when different compounds converge through diverse modes-of-action on common endpoints, like oligodendrocyte differentiation in this study. This case study using FRs suggests that human cell–based DNT in vitro battery is a promising approach for neurodevelopmental hazard assessment and compound prioritization in risk assessment. Graphical abstract


2007 ◽  
Vol 97 (1) ◽  
pp. 94-102 ◽  
Author(s):  
E. K. Pacyniak ◽  
X. Cheng ◽  
M. L. Cunningham ◽  
K. Crofton ◽  
C. D. Klaassen ◽  
...  

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