Diastereomer-Specific Uptake, Translocation, and Toxicity of Hexabromocyclododecane Diastereoisomers to Maize

Abstract

Hexabromocyclododecane (HBCD), a brominated flame retardant, has become a ubiquitous contaminant due to its wide application, persistence, and toxicity. HBCD diastereoisomers have different physical and chemical properties and may differ in their bioaccumulation and toxicity in plants. Accumulation and toxicity of α-, β-, and γ-HBCDs in maize were investigated in the present study. The accumulation was in the order β-HBCD > α-HBCD > γ-HBCD in roots and β-HBCD > γ-HBCD > α-HBCD in shoots. Both the inhibitory effect of the diastereoisomers on the early development of maize and the intensities of hydroxyl radical and histone H2AX phosphorylation in maize exposed to 2 μg L −1 HBCD followed the order α-HBCD > β-HBCD > γ-HBCD, indicating the diastereomer-specific oxidative stress and DNA damage in maize. It was further confirmed that the generation of reactive oxygen species was one, but not the only, mechanism for DNA damage in maize exposed to HBCDs.

Hexabromocyclododecanes (HBCDDs) in surface soils from coastal cities in North China: Correlation between diastereoisomer profiles and industrial activities

“…Except for raw HBCDD production, brominated flame retardant manufacture, EPS and XPS board processing, flame retardant textile processing, electric and electronic component production, e-waste recycling industries are all located in this region, which are potential sources of HBCDD release. It is also an important agricultural region where arable crops, vegetables and fruits are produced/ cultivated at large scale, while HBCDD can be absorbed by plants (Wu et al, 2012;Zhang et al, 2013). Therefore, the monitoring of HBCDD contaminants in soils is necessary to ensure food safety.…”

Occurrence of halogenated flame retardants in commercial seafood species available in European markets

“…It has also been detected in environmental, biotic and human samples (Eljarrat et al, 2004, Eljarrat et al, 2009, Guerra et al, 2010a. The technical products contain roughly 1-12 % of each of the α and β diastereoisomers, and 75-89 % of the γ diastereoisomer (Wu et al, 2012). However, the α diastereoisomer has the highest occurrence in food (Barghi et al, 2016).…”

Accumulation and phytotoxicity of technical hexabromocyclododecane in maize

“…4a, taking the concentration of 0.01 mg/L as an example). The variations of signal intensity of the PBN-radical adducts in the EPR spectra reflected the generation of hydroxyl radical ( U OH), and the U OH intensity was calculated by the signal intensity of the second couple of the triplet, according to our previous study (Wu et al, 2012). Weak U OH signals were found in the control without HBCD exposure (Fig.…”

“…Nevertheless, phytotoxicity information on technical HBCD is lacking. Although we have investigated the accumulation and toxicity of each HBCD diastereoisomer in maize in our previous work (Wu et al, 2012), the contribution of each diastereoisomer in the technical mixture to HBCD accumulation in plants is still unknown.…”