5 research outputs found
Ubiquitous Occurrence of Fluorotelomer Alcohols in Eco-Friendly Paper-Made Food-Contact Materials and Their Implication for Human Exposure
The occurrence of fluorotelomer alcohols (FTOHs) was investigated
in 94 food-contact materials (FCMs). We detected 6:2 FTOH (<0.60–1110
ng/g), 8:2 FTOH (<0.40–8490 ng/g), and 10:2 FTOH (<0.02–9350
ng/g) in most FCM samples, and four longer-chain C<sub>14–20</sub> FTOHs were, for the first time, identified in FCMs with relatively
high concentrations (<0.02–8450 ng/g for 12:2 FTOH, <0.02–1640
ng/g for 14:2 FTOH, <0.02–372 ng/g for 16:2 FTOH, and <0.02–130
ng/g for 18:2 FTOH). There were three typical profiles of FTOHs that
were dominated by 6:2 FTOH (95.6 ± 8.1% in 9 FCMs), 8:2 FTOH
(50.9 ± 20.8% in 22 FCMs), and 10:2 FTOH (44.5 ± 20.9% in
30 FCMs), indicating the congener-specific usage of FTOHs for different
commercial purposes. All nine detectable FCMs produced in the United
States were dominated by 6:2 FTOH, which was significantly different
from those produced in China. The median concentration of total FTOHs
in eco-friendly paper tableware was 2990 ng/g, which was lower than
in popcorn bags (18 200 ng/g) but much higher than other FCMs
(<0.55–38.7 ng/g). FTOHs could migrate from paper bowls,
with migration efficiencies of 0.004–0.24% into water, 0.004–0.24%
into 10% ethanol, 0.009–2.79% into 30% ethanol, 0.06–13.0%
into 50% ethanol (v/v) simulants, and 0.04–2.28% into oil.
Migration efficiencies decreased with increasing carbon chain lengths
of FTOHs
Occurrence and Source of Nitrosamines and Secondary Amines in Groundwater and its Adjacent Jialu River Basin, China
The presence of mutagenic and carcinogenic nitrosamines
in groundwater
is of great concern. In this study, eight nitrosamines including <i>N</i>-nitrosodimethylamine (NDMA), <i>N</i>-nitrosodiethylamine
(NDEA), <i>N</i>-nitrosomethylethylamine (NMEA), <i>N</i>-nitrosopyrrolidine (NPYR), <i>N</i>-nitrosomorpholine
(NMOR), <i>N</i>-nitrosopiperidine (NPIP), <i>N</i>-nitrosodi-n-propylamine (NDPA), and <i>N</i>-nitrosodi-n-butylamine
(NDBA) and corresponding secondary amines were investigated in shallow
groundwater, river water, and wastewater samples collected from the
Jialu River basin. The total concentrations of nitrosamines and secondary
amines in groundwater were ND–101.1 ng/L and 0.36–4.38
μg/L, respectively. NDMA and its secondary amine DMA (44.7%/40.1%)
were the predominant compounds in groundwater, followed by NDEA/DEA
(21.7%/29.3%) and NDBA/DBA (26.4%/27.4%). Relatively high concentrations
of these six compounds were also observed in river water that was
influenced by the direct discharge of industrial and domestic wastewater.
Using acesulfame as a quantitative population marker, the contribution
of domestic sources to the concentrations of nitrosamines and secondary
amines was 39–85% in downstream reaches of the Jialu River,
and that of industrial sources was estimated to be 65–98% in
other sites of the area. Both on-site leakage of domestic and industrial
wastewater and leaching from river water would contribute to the occurrence
of target pollutants in groundwater. The target pollutants posed a
cancer risk of 4.12 × 10<sup>–5</sup> to the local populations
due to the direct usage of groundwater as potable water
Biosensor Medaka for Monitoring Intersex Caused by Estrogenic Chemicals
Estrogenic
chemicals can induce intersex in fish species leading
to disturbance of spermatogenesis and impairment of reproductive success.
To overcome the shortcomings of conventional histopathological observation
on intersex (low sensitivity, relatively poor accuracy, long experimental
periods, as well as laborious and time-consuming), we generated a
pMOSP1-EGFP transgenic medaka fish model. In this transgenic fish,
the green fluorescence protein (GFP) reporter gene was derived by
the regulatory elements of the OSP1 gene, which is a specific and
sensitive molecular biomarker for indicating intersex occurrence in
male medaka fish exposed to estrogenic chemicals. The transgenic GFP
was faithfully expressed in ovaries and in testes with intersex, perfectly
mimicking the expression pattern of endogenous OSP1. In intersex testis,
the diameters of primary oocytes which could be distinguished by GFP
fluorescence observation were as small as 10 μm, lower than
that (more than 20 μm) which is observable by histopathology.
Using the novel transgenic medaka fish, intersex was observed after
90-day exposure to 0.75 ng/L 17α-ethinyloestradiol (EE<sub>2</sub>) (0–90 dph), but only at concentrations of at least 1.38
ng/L EE<sub>2</sub> by histopathology. An effectiveness of a short-term
in vivo assay for screening estrogenic chemicals that can monitor
intersex appearance at early sex developmental stage (about 30 dph)
in male medaka fish was also demonstrated by assessing the intersex
induction of EE<sub>2</sub>, 17β-estradiol and 4-nonylphenol.
This newly developed assay provides an enhanced ability for screening
and testing estrogenic chemicals with the potential to induce intersex
and studying their biological impacts
Comprehensive Characterization of Organic Light-Emitting Materials in Breast Milk by Target and Suspect Screening
Organic light-emitting materials (OLEMs) are emerging
contaminants
in the environment and have been detected in various environment samples.
However, limited information is available regarding their contamination
within the human body. Here, we developed a novel QuEChERS (quick,
easy, cheap, effective, rugged, and safe) method coupled with triple
quadrupole/high-resolution mass spectrometry to determine OLEMs in
breast milk samples, employing both target and suspect screening strategies.
Our analysis uncovered the presence of seven out of the 39 targeted
OLEMs in breast milk samples, comprising five liquid crystal monomers
and two OLEMs commonly used in organic light-emitting diode displays.
The cumulative concentrations of the seven OLEMs in each breast milk
sample ranged from ND to 1.67 × 103 ng/g lipid weight,
with a mean and median concentration of 78.76 and 0.71 ng/g lipid
weight, respectively, which were higher compared to that of typical
organic pollutants such as polychlorinated biphenyls and polybrominated
diphenyl ethers. We calculated the estimated daily intake (EDI) rates
of OLEMs for infants aged 0–12 months, and the mean EDI rates
during lactation were estimated to range from 30.37 to 54.89 ng/kg
bw/day. Employing a suspect screening approach, we additionally identified
66 potential OLEMs, and two of them, cholesteryl hydrogen phthalate
and cholesteryl benzoate, were further confirmed using pure reference
standards. These two substances belong to cholesteric liquid crystal
materials and raise concerns about potential endocrine-disrupting
effects, as indicated by in silico predictive models.
Overall, our present study established a robust method for the identification
of OLEMs in breast milk samples, shedding light on their presence
in the human body. These findings indicate human exposure to OLEMs
that should be further investigated, including their health risks
Comprehensive Characterization of Organic Light-Emitting Materials in Breast Milk by Target and Suspect Screening
Organic light-emitting materials (OLEMs) are emerging
contaminants
in the environment and have been detected in various environment samples.
However, limited information is available regarding their contamination
within the human body. Here, we developed a novel QuEChERS (quick,
easy, cheap, effective, rugged, and safe) method coupled with triple
quadrupole/high-resolution mass spectrometry to determine OLEMs in
breast milk samples, employing both target and suspect screening strategies.
Our analysis uncovered the presence of seven out of the 39 targeted
OLEMs in breast milk samples, comprising five liquid crystal monomers
and two OLEMs commonly used in organic light-emitting diode displays.
The cumulative concentrations of the seven OLEMs in each breast milk
sample ranged from ND to 1.67 × 103 ng/g lipid weight,
with a mean and median concentration of 78.76 and 0.71 ng/g lipid
weight, respectively, which were higher compared to that of typical
organic pollutants such as polychlorinated biphenyls and polybrominated
diphenyl ethers. We calculated the estimated daily intake (EDI) rates
of OLEMs for infants aged 0–12 months, and the mean EDI rates
during lactation were estimated to range from 30.37 to 54.89 ng/kg
bw/day. Employing a suspect screening approach, we additionally identified
66 potential OLEMs, and two of them, cholesteryl hydrogen phthalate
and cholesteryl benzoate, were further confirmed using pure reference
standards. These two substances belong to cholesteric liquid crystal
materials and raise concerns about potential endocrine-disrupting
effects, as indicated by in silico predictive models.
Overall, our present study established a robust method for the identification
of OLEMs in breast milk samples, shedding light on their presence
in the human body. These findings indicate human exposure to OLEMs
that should be further investigated, including their health risks