Comparative Study of Genotoxicity Induced by Six Different PBDEs

Abstract

Indiscriminate use of synthetic substances has led to environmental contamination and increasing human and animal exposure to harmful chemicals. Polybrominated flame retardants (PBDEs), which serve as non-covalent additives that enhance the safety of a variety of commercial and consumer goods, are an important class among potentially damaging synthetic substances. Its use is very common in developing countries, including Brazil. In theory, 209 different PBDE congeners exist, and many are currently being used during the manufacture of several products. Unfortunately, PBDEs are easily released from the original products, promptly reaching the environment. Knowledge about the toxicological power of these substances is still limited, which has prevented environmental and regulatory authorities from conducting adequate risk assessments. This research addresses the genotoxic and mutagenic potential of PBDEs. The effects of HepG2 cells and Salmonella typhimurium exposure to six main representatives of PBDEs, namely tetrabromodiphenyl ether (BDE-47), pentabromodiphenyl ether (BDE-99 and BDE-100), hexabromodiphenyl ether (BDE-153 and BDE-154) and decabromodiphenyl ether (BDE-209), were evaluated. The comet assay revealed that all the assessed BDEs exerted genotoxic effects but induced no micronuclei formation in HepG2 cells. These BDEs had no significant mutagenic effects on the Salmonella typhimurium strains TA98 and TA100. Taken together, the results of the genomic instability assays showed that PBDEs can represent a risk to the health of directly and indirectly exposed population, because the assessed BDEs induce genotoxic effects in the HepG2 cell line.

Hepatic oxidative stress, DNA damage and apoptosis in adult zebrafish following sub‐chronic exposure to BDE‐47 and BDE‐153

“…Although the specific mechanism through which BDE‐47 and BDE‐153 elicit DNA damage remains vague, even in this study, our findings could reveal that the imbalance of ROS production might cause genotoxicity in the zebrafish liver. in vitro studies also indicated different PBDEs congeners including BDE‐47 and BDE‐153 could induce genotoxic effects 25 . In the present study, induced oxidative stress in living tissues could result in excess ROS, which may directly react with biological molecules such as DNA or indirectly act as signal molecules to mediate genotoxicity 44 …”

“…in vitro studies also indicated different PBDEs congeners including BDE-47 and BDE-153 could induce genotoxic effects. 25 In the present study, induced oxidative stress in living tissues could result in excess ROS, which may directly react with biological molecules such as DNA or indirectly act as signal molecules to mediate genotoxicity. 44…”

“…The induced effects of xenobiotics related to DNA damage and apoptosis have been well investigated by in vitro or ex vivo studies. For example, previous studies indicated that different PBDE congeners including BDE‐47 and BDE‐153 induced mitochondrial damage, genetoxicity, and apoptosis in rat liver and HepG2 cells 25‐29 . However, in vivo studies, the DNA damage and apoptosis induced by PBDEs still need to be further explored.…”

“…For example, previous studies indicated that different PBDE congeners including BDE-47 and BDE-153 induced mitochondrial damage, genetoxicity, and apoptosis in rat liver and HepG2 cells. [25][26][27][28][29] However, in vivo studies, the DNA damage and apoptosis induced by PBDEs still need to be further explored.…”

Chemical, structural, and ultrastructural analysis of waste from the carrageenan and sugar-bioethanol processes for future bioenergy generation

“…In recent years, our research group has attempted to elucidate the toxic effects of PBDEs. We have recently published that BDE-153 and other congeners can cause genomic instability, as revealed by comet assay results obtained after exposure to BDE-153 at 5, 10, or 25 μM for only 4 h [38]. In addition, we have shown the same compound can induce HepG2 cell autophagy [39,40] in an attempt to save cells from the damage caused by BDE-153.…”