2 research outputs found
Occurrence of Natural Mixed Halogenated Dibenzo‑<i>p</i>‑Dioxins: Specific Distribution and Profiles in Mussels from Seto Inland Sea, Japan
In addition to unintentional formation
of polychlorinated (PCDD/Fs),
polybrominated (PBDD/Fs), and mixed halogenated (PXDD/Fs) dibenzo-<i>p</i>-dioxins/dibenzofurans during industrial activities, recent
studies have shown that several PBDD and PXDD congeners can be produced
by marine algal species from the coastal environment. However, multiple
exposure status of anthropogenic and naturally derived dioxins in
marine organisms remains unclear. The present study examined the occurrence,
geographical distribution, and potential sources of PCDD/Fs, PBDD/Fs,
and PXDD/Fs using mussels and brown algae collected in 2012 from Seto
Inland Sea, Japan. The results showed the widespread occurrence of
not only PCDD/Fs but also PBDDs and PXDDs in Seto Inland Sea. The
geographical distribution pattern of PBDDs was similar to that of
PXDDs, which were obviously different from that of PCDDs and PCDFs,
and a significant positive correlation was observed between the levels
of their predominant congeners, i.e., 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs.
Interestingly, potential precursors of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs,
hydroxylated tetrabrominated diphenyl ethers (6-HO-BDE-47 and 2′-HO-BDE-68)
and their mixed halogenated analogue (HO-TrBMoCDE), were also identified
in the mussel and brown alga samples collected at the same site, by
comprehensive two-dimensional gas chromatography with time-of-flight
mass spectrometry (GC × GC–ToFMS) analyses. It is noteworthy
that residue levels of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs in the mussel
were 30 times higher than those in the brown alga, suggesting the
bioaccumulation of these natural dioxins
Similarities in the Endocrine-Disrupting Potencies of Indoor Dust and Flame Retardants by Using Human Osteosarcoma (U2OS) Cell-Based Reporter Gene Assays
Indoor
dust is a sink for many kinds of pollutants, including flame retardants
(FRs), plasticizers, and their contaminants and degradation products.
These pollutants can be migrated to indoor dust from household items
such as televisions and computers. To reveal high-priority end points
of and contaminant candidates in indoor dust, using CALUX reporter
gene assays based on human osteosarcoma (U2OS) cell lines, we evaluated
and characterized the endocrine-disrupting potencies of crude extracts
of indoor dust collected from Japan (<i>n</i> = 8), the
United States (<i>n</i> = 21), Vietnam (<i>n</i> = 10), the Philippines (<i>n</i> = 17), and Indonesia
(<i>n</i> = 10) and for 23 selected FRs. The CALUX reporter
gene assays used were specific for compounds interacting with the
human androgen receptor (AR), estrogen receptor α (ERα),
progesterone receptor (PR), glucocorticoid receptor (GR), and peroxisome
proliferator-activated receptor γ2 (PPARγ2). Indoor dust
extracts were agonistic to ERα, GR, and PPARγ2 and antagonistic
against AR, PR, GR, and PPARγ2. In comparison, a majority of
FRs was agonistic to ERα and PPARγ2 only, and some FRs
demonstrated receptor-specific antagonism against all tested nuclear
receptors. Hierarchical clustering clearly indicated that agonism
of ERα and antagonism of AR and PR were common, frequently detected
end points for indoor dust and tested FRs. Given our previous results
regarding the concentrations of FRs in indoor dust and in light of
our current results, candidate contributors to these effects include
not only internationally controlled brominated FRs but also alternatives
such as some phosphorus-containing FRs. In the context of indoor pollution,
high-frequency effects of FRs such as agonism of ERα and antagonism
of AR and PR are candidate high-priority end points for further investigation