Probabilistic risk assessment of dietary exposure to benzophenone derivatives in cereals in Taiwan.

Benzophenone (BP) and BP derivatives (BPDs) are widely used as ultraviolet (UV) stabilizers in food packaging materials and as photoinitiators in UV-curable inks for printing on food-contact materials. However, our knowledge regarding the sources and risks of dietary exposure to BP and BPDs in cereals remains limited, which prompted us to conduct this study. We measured the levels of BP and nine BPDs-BP-1, BP-2, BP-3, BP-8, 2-hydroxybenzophenone, 4-hydroxybenzophenone, 4-methylbenzophenone (4-MBP), methyl-2-benzoylbenzoate, and 4-benzoylbiphenyl-in three types of cereals (rice flour, oatmeal, and cornflakes; 180 samples in total). A Bayesian Markov-chain Monte Carlo (MC) simulation approach was used for deriving the posterior distributions of BP and BPD residues. This approach helped in addressing the uncertainty in probabilistic distribution for the sampled data under the detection limit. Through an MC simulation, we calculated the daily exposure levels of dietary BP and BPDs and corresponding health risks. The results revealed the ubiquitous presence of BP, BP-3, and 4-MBP in cereals. Older adults (aged >65 years) had the highest (97.5 percentile) lifetime carcinogenic risk for BP exposure through cereals (9.41 × 10-7), whereas children aged 0-3 years had the highest (97.5 percentile) hazard indices for BPD exposure through cereals (2.5 × 10-2). Nevertheless, across age groups, the lifetime carcinogenic risks of BP exposure through cereals were acceptable, and the hazard indices for BPD exposure through cereals were <1. Therefore, BPD exposure through cereals may not be a health concern for individuals in Taiwan.

Effects of antibiotics and metals on lung and intestinal microbiome dysbiosis after sub-chronic lower-level exposure of air pollution in ageing rats.

We investigated the effects of antibiotics, drugs, and metals on lung and intestinal microbiomes after sub-chronic exposure of low-level air pollution in ageing rats. Male 1.5-year-old Fischer 344 ageing rats were exposed to low-level traffic-related air pollution via whole-body exposure system for 3 months with/without high-efficiency particulate air (HEPA) filtration (gaseous vs. particulate matter with aerodynamic diameter of ≤2.5 µm (PM2.5) pollution). Lung functions, antibiotics, drugs, and metals in lungs were examined and linked to lung and fecal microbiome analyses by high-throughput sequencing analysis of 16 s ribosomal (r)DNA. Rats were exposed to 8.7 µg/m3 PM2.5, 10.1 ppb NO2, 1.6 ppb SO2, and 23.9 ppb O3 in average during the study period. Air pollution exposure decreased forced vital capacity (FVC), peak expiratory flow (PEF), forced expiratory volume in 20 ms (FEV20), and FEF at 25∼75% of FVC (FEF25-75). Air pollution exposure increased antibiotics and drugs (benzotriazole, methamphetamine, methyl-1 H-benzotriazole, ketamine, ampicillin, ciprofloxacin, pentoxifylline, erythromycin, clarithromycin, ceftriaxone, penicillin G, and penicillin V) and altered metals (V, Cr, Cu, Zn, and Ba) levels in lungs. Fusobacteria and Verrucomicrobia at phylum level were increased in lung microbiome by air pollution, whereas increased alpha diversity, Bacteroidetes and Proteobacteria and decreased Firmicutes at phylum level were occurred in intestinal microbiome. Lung function decline was correlated with increasing antibiotics, drugs, and metals in lungs as well as lung and intestinal microbiome dysbiosis. The antibiotics, drugs, and Cr, Co, Ca, and Cu levels in lung were correlated with lung and intestinal microbiome dysbiosis. The lung microbiome was correlated with intestinal microbiome at several phylum and family levels after air pollution exposure. Our results revealed that antibiotics, drugs, and metals in the lung caused lung and intestinal microbiome dysbiosis in ageing rats exposed to air pollution, which may lead to lung function decline.

Proteomic analysis of rat kidney under maleic acid treatment by SWATH-MS technology.

RATIONALE: Maleic acid is an industrial-grade chemical that is often used in adhesives, stabilizers, and preservatives. It is unknown whether long-term consumption of maleic acid modified starch is harmful to humans. However, many studies have indicated that maleic acid causes renal tubular damage in animal models, even as the associated pathways remain unclear. Sequential window acquisition of all theoretical fragment ion spectra (SWATH) is the most innovative of the label-free quantitative technologies which have better quantification performance. Therefore, SWATH technology was used to investigate the effect of maleic acid on the rat kidney proteome in this study. METHODS: Sprague-Dawley(SD) rats were treated with 0 mg/kg (control), 6 mg/kg (low-dose), 10 mg/kg (medium-dose), and 60 mg/kg (high-dose) of maleic acid. After kidney protein extraction, 28% SDS-PAGE was used, followed by in-gel digestion and desalting. Next, the samples were analyzed with ultra-performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight mass spectrometry (Q-TOF MS), and data-dependent acquisition (DDA) and SWATH technology were also used. The gene ontology and pathway analysis were accomplished. Ultimately, these protein biomarkers were validated by using scheduled high-resolution multiple reaction monitoring (sMRMHR ). RESULTS: Comparisons of the control group with the other three groups revealed that 95, 130, and 103 proteins were expressed at significantly different levels in the control group and in the low-dose, medium-dose, and high-dose groups, respectively. According to the gene ontology analysis, the major processes that these proteins were involved in were metabolic processes, biological regulation, cellular processes, and responses to stimuli; the major functions that these proteins were involved in were binding, hydrolase activity, catalytic activity, and oxidoreductase activity; and the major cellular components hat they were involved in were the cytoplasm, extracellular region, membrane, and mitochondria. According to the KEGG pathway analysis, these proteins were involved in 35 pathways, five of which, the carbohydrate metabolism, folate biosynthesis, renal tubular resorption, amino acid metabolism, and Ras signaling pathways, are discussed in this study. Ultimately, 19 proteins involved in 12 important pathways were validated by sMRMHR . CONCLUSIONS: It was demonstrated that maleic acid caused insufficient energy production, which might lead to a decrease in the activity of the sodium-potassium ATP pump and hydrogen ion ATP pump, which could in turn have caused renal tubular resorption and hydrogen ion regulation to be blocked, thus leading to the accumulation of hydrogen ions in the renal tubules, which would then result in renal tubular acidification followed finally by Fanconi syndrome.

Urinary phthalate metabolites are associated with biomarkers of DNA damage and lipid peroxidation in pregnant women - Tainan Birth Cohort Study (TBCS).

Phthalate exposure and oxidative stress have been linked to adverse reproductive outcomes in experimental studies, whereas no clear line has been drawn for human, especially in pregnant women. This study explored relationships between urinary phthalate metabolites and biomarkers of lipid peroxidation and oxidative and nitrosative DNA damage. Measurements from 97 Taiwanese pregnant women were taken at three different times during second and third trimesters. Five oxidative/nitrosative stress biomarkers - 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO2Gua), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-isoprostaglandin F2α (8-isoPF2α), and malondialdehyde (MDA), and 11 phthalate metabolites were measured in urine samples. Linear regressions in each visit and linear mixed-model regressions were fitted to estimate percent changes in oxidative/nitrosative stress biomarkers resulting from inter-tertile increase of phthalate metabolite level and the cumulative concentrations of di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate. The highest urine concentrations of phthalate metabolites and the greatest number of significant positive associations between phthalate metabolites and oxidative/nitrosative stress biomarkers were observed in the third visit and in repeated measurements analysis, respectively. Of the biomarkers related to DNA damage, 8-OHdG (25.4% inter-tertile increase for mono-iso-butyl phthalate) was more sensitive to phthalate exposure than 8-NO2Gua. Among the biomarkers of lipid peroxidation, HNE-MA (61.2% inter-tertile increase for sum of DEHP metabolites) was more sensitive than 8-isoPF2α and MDA. Our findings support the hypothesis that pregnant phthalate exposure increases the oxidative stress biomarkers of DNA damage and lipid peroxidation. Future research may elucidate the mediating roles of oxidative/nitrosative stress biomarkers in the link between phthalate exposure and adverse reproductive outcomes.

Neuropathology changed by 3- and 6-months low-level PM2.5 inhalation exposure in spontaneously hypertensive rats.

BACKGROUND: Epidemiological evidence has linked fine particulate matter (PM2.5) to neurodegenerative diseases; however, the toxicological evidence remains unclear. The objective of this study was to investigate the effects of PM2.5 on neuropathophysiology in a hypertensive animal model. We examined behavioral alterations (Morris water maze), lipid peroxidation (malondialdehyde (MDA)), tau and autophagy expressions, neuron death, and caspase-3 levels after 3 and 6 months of whole-body exposure to urban PM2.5 in spontaneously hypertensive (SH) rats. RESULTS: SH rats were exposed to S-, K-, Si-, and Fe-dominated PM2.5 at 8.6 ± 2.5 and 10.8 ± 3.8 µg/m3 for 3 and 6 months, respectively. We observed no significant alterations in the escape latency, distance moved, mean area crossing, mean time spent, or mean swimming velocity after PM2.5 exposure. Notably, levels of MDA had significantly increased in the olfactory bulb, hippocampus, and cortex after 6 months of PM2.5 exposure (p < 0.05). We observed that 3 months of exposure to PM2.5 caused significantly higher expressions of t-tau and p-tau in the olfactory bulb (p < 0.05) but not in other brain regions. Beclin 1 was overexpressed in the hippocampus with 3 months of PM2.5 exposure, but significantly decreased in the cortex with 6 months exposure to PM2.5. Neuron numbers had decreased with caspase-3 activation in the cerebellum, hippocampus, and cortex after 6 months of PM2.5 exposure. CONCLUSIONS: Chronic exposure to low-level PM2.5 could accelerate the development of neurodegenerative pathologies in subjects with hypertension.

Interactive effects of nonylphenol and bisphenol A exposure with oxidative stress on fetal reproductive indices.

Nonylphenol (NP) and/or bisphenol A (BPA) may have reproductive effects. Although the mechanisms of action remain unclear, steroid hormones biosynthesis, hypothalamus pituitary adrenal axis activity, oxidative stress, and crosstalk interaction of NP and BPA mixture and its pathways may play a contributory role. This cross-sectional study examined whether the interactive effects of NP/BPA and oxidative stress biomarkers played a role in reproductive indices (penis length and anogenital distance (AGD)) in 244 mother-fetus pairs. Four biomarkers of oxidative stress, (8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO2Gua), 8-iso-prostaglandin F2α (8-isoPF2α), and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)) were simultaneously analyzed using the high-performance liquid chromatography-electrospray ionization tandem mass spectrometry method. No significant associations were found between reproductive indices and NP/BPA or oxidative stress biomarkers. Maternal exposure to a mixture of NP and BPA may enhance 8-OHdG. Interactive effects were found in the high 8-isoPF2α group, and prenatal NP exposure was inversely associated with penis length (ß = -3.68 mm; p = 0.01). Similar results were noted among boys who were born to mothers in the high 8-isoPF2α group, in which BPA was inversely associated with penis length (ß = -4.43 mm; p = 0.005). Our findings suggest important implications for prenatal exposure to oxidative stress, as evidenced by the 8-isoPF2α level. Thus, NP and BPA may interact to shape fetal reproductive tract development, particularly in boys. The interactive effects of NP/BPA, oxidative stress, and reproductive indices should be considered.

The interactions among organophosphate pesticide exposure, oxidative stress, and genetic polymorphisms of dopamine receptor D4 increase the risk of attention deficit/hyperactivity disorder in children.

OBJECTIVE: The aim of this study was to clarify the association between organophosphate pesticides (OPs) and attention-deficit/hyperactivity disorder (ADHD) related to oxidative stress and genetic polymorphisms. METHODS: This case-control study enrolled 93 children with ADHD and 112 control children in north Taiwan. Six dialkyl phosphate (DAP) metabolites of OPs and oxidative stress biomarkers were analyzed. Polymorphisms of the dopamine receptor D4 gene (DRD4) were identified. RESULTS: Children with ADHD had significantly higher dimethylphosphate (DMP, 236.69nmol/g cre. vs. 186.84nmol/g cre., p value = 0.01) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA, 28.95µg/g cre. vs. 16.55µg/g cre., p value<0.01) concentrations than control children. Children who carried DRD4 GA/AA genotypes (rs752306) were less likely than those who carried the DRD4 GG genotype to have ADHD (odds ratio [OR]: 0.45, 95% CI: 0.24-0.84). The estimated value of the AP (attributable proportion due to interaction) was 0.59 (95% CI: 0.13-1.05), indicating that 59% of ADHD cases in DMP-exposed children with the DRD4 GG genotype were due to the gene-environment interaction. After adjustment for other covariates, children who carried the DRD4 GG genotype, had been exposed to high DMP levels (more than the median), and had high HNE-MA levels had a significantly increased risk for developing ADHD (OR = 11.74, 95% CI: 2.12-65.04). CONCLUSION: This study indicated a gene-environment interaction in the risk of ADHD in children. The association between DMP and ADHD in children might relate to the mechanism of lipid peroxidation. Dose-response relationships and the combined effects of OPs, oxidative stress, and genetic polymorphism on ADHD should not be neglected.

Prenatal Nonylphenol and Bisphenol A Exposures and Inflammation Are Determinants of Oxidative/Nitrative Stress: A Taiwanese Cohort Study.

Prenatal exposure to nonylphenol (NP) and/or bisphenol A (BPA) has been reported to be associated with adverse birth outcomes; however, the underlying mechanisms remain unclear. The primary mechanism is endocrine disruption of the binding affinity for the estrogen receptor, but oxidative stress and inflammation might also play a contributory role. We aimed to investigate urinary NP and BPA levels in relation to biomarkers of oxidative/nitrative stress and inflammation and to explore whether changes in oxidative/nitrative stress are a function of prenatal exposure to NP/BPA and inflammation in 241 mother-fetus pairs. Third-trimester urinary biomarkers of oxidative/nitrative stress were simultaneously measured, including products of oxidatively and nitratively damaged DNA (8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-nitroguanine (8-NO2Gua)) as well as products of lipid peroxidation (8-iso-prostaglandin F2α (8-isoPF2α) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)). The antioxidant glutathione peroxidase (GPx) and inflammation biomarkers, including C-reactive protein (CRP) and a panel of cytokines (interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)), were analyzed in maternal and umbilical cord plasma samples. In adjusted models, we observed significant positive associations between NP exposure and 8-OHdG and 8-NO2Gua levels, between BPA and 8-isoPF2α levels, and between maternal CRP levels and HNE-MA levels. Additionally, BPA and TNF-α levels in cord blood were inversely associated with maternal and GPx levels in cord blood as well as maternal TNF-α levels were inversely associated with maternal GPx levels. These results support a role for exposure to NP and BPA and possibly inflammation in increasing oxidative/nitrative stress and decreasing antioxidant activity during pregnancy.

Nuclear magnetic resonance- and mass spectrometry-based metabolomics to study maleic acid toxicity from repeated dose exposure in rats.

Maleic acid (MA), a chemical intermediate used in many consumer and industrial products, was intentionally adulterated in a variety of starch-based foods and instigated food safety incidents in Asia. We aim to elucidate possible mechanisms of MA toxicity after repeated exposure by (1) determining the changes of metabolic profile using 1 H nuclear magnetic resonance spectroscopy and multivariate analysis, and (2) investigating the occurrence of oxidative stress using liquid chromatography tandem mass spectrometry by using Sprague-Dawley rat urine samples. Adult male rats were subjected to a 28 day subchronic study (0, 6, 20 and 60 mg kg-1 ) via oral gavage. Urine was collected twice a day on days 0, 7, 14, 21 and 28; organs underwent histopathological examination. Changes in body weight and relative kidney weights in medium- and high-dose groups were significantly different compared to controls. Morphological alterations were evident in the kidneys and liver. Metabolomic results demonstrated that MA exposure increases the urinary concentrations of 8-hydroxy-2'-deoxyguanosine, 8-nitroguanine and 8-iso-prostaglandin F2α ; levels of acetoacetate, hippurate, alanine and acetate demonstrated time- and dose-dependent variations in the treatment groups. Findings suggest that MA consumption escalates oxidative damage, membrane lipid destruction and disrupt energy metabolism. These aforementioned changes in biomarkers and endogenous metabolites elucidate and assist in characterizing the possible mechanisms by which MA induces nephro- and hepatotoxicity.

Concentrations, compositional profiles, and health risks of benzophenones among the Taiwanese population based on analysis of 23 daily consumed foods.

In this study, we analyzed the occurrence and distribution of 11 benzophenone-type ultraviolet filters (BPs) in 893 food samples spanning 7 food categories in Taiwan. We conducted a Monte Carlo simulation to determine the carcinogenic and noncarcinogenic risks of BPs. The results indicated that cornflakes had the highest mean level of BPs (103 ng/g), followed by bread (101 ng/g) and pastries (59 ng/g). BP was the most prevalent category, followed by 4-methylbenzophenone (4-MBP), 2-hydroxybenzophenone, and benzophenone-3. Estimation of the lifetime cancer risk (LTCR) of BP (average life expectancy of 80 years) placed them in the 50th and 97.5th percentiles [P50 (P97.5)] LTCR of 1.9 × 10-7 (5.7 × 10-6), indicating that BP in food poses a low renal hazard to the Taiwanese population. The noncarcinogenic risk of BPs was evaluated using a hazard quotient and combined margin of exposure (MOET), revealing a P50 (P97.5) hazard index of < 1 for BP, 4-MBP, and methyl-2-benzoylbenzoate. Although the P50 MOET values for all age groups were within the moderate range of concern, with a more conservative extreme (P2.5), the MOET values for the 0-3, 3-6, and 6-12 age groups fell below 100, indicating a high concern for renal degeneration and hyperplasia.

Associations between paraben exposure, thyroid capacity, homeostasis and pituitary thyrotropic function in the general Taiwanese: Taiwan Environmental Survey for Toxicants (TEST) 2013.

Several studies have suggested that some endocrine disruptors such as synthetic phenols, parabens and phthalates may disrupt thyroid hormone signaling and associated negative feed-backs with the central hypothalamic-pituitary-thyroid (HPT) axis. Therefore, we investigated urinary paraben and blood thyroid hormone levels in the Taiwanese population. Our sample comprised 264 adults (aged 18-97 years) and 75 minors (aged 7-17 years) from Taiwan Environmental Survey for Toxicants 2013. Urinary levels of methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) were assessed. Hormones of particular interest include: thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). We sought integrated parameters to describe the transfer of thyroid hormones in homeostatic models. The geometric mean urinary paraben levels of the adults were higher than those of the minors (adults vs. minors; MeP: 383 vs. 62.4 ng/mL; PrP: 109 vs. 8.00 ng/mL; EtP: 39.5 vs. 2.38 ng/mL, and BuP: 6.36 vs. 2.13 ng/mL). In the male adults, we discovered that 0.253% (p = 0.032), 0.256% (p = 0.041) and 0.257% (p = 0.037) decreases in the TSH, TSH/T4 and TSH/FreeT4 ratio was associated with 1% EtP increases, respectively. In the female minors, 0.093% (p = 0.044), 0.072% (p = 0.047) and 0.156 (p = 0.004) increases in the TSH ratios were associated with a 1% MeP, EtP and BuP increase, respectively. Moreover, 0.151% (p = 0.008) and 0.177% (p = 0.001) increases in TSH/T4 and TSH/free T4 ratios were associated with a BuP 1% increase, respectively. Finally, EtP was positively associated with SPINA-GT (ß: 15.66, p = 0.036) in the male adults. By contrast, EtP were positively associated with Jostel's TSH index and sTSHI (ß: 0.072, p = 0.049; ß: 0.107, p = 0.049) in the female minors. The Taiwanese population is commonly exposed to parabens, which can potentially lead to alteration of thyroid hormone homeostasis.

Determination of 16 ultraviolet-absorbing compounds in marine invertebrates by using LC-USI-MS/MS coupled with QuEChERS.

In this study, we examined multiple endocrine-disrupting ultraviolet-absorbing compounds (UVACs) in marine invertebrates used in personal care products and packaging. Modified QuEChERS and liquid chromatography UniSpray ionization tandem mass spectrometry were used to identify 16 UVACs in marine invertebrates. Matrix-matched calibration curves revealed high linearity (r ≥ 0.9929), with limits of detection and quantification of 0.006-1.000 and 0.020-3.000 ng/g w.w., respectively. In oysters, intraday and interday analyses revealed acceptable accuracy (93%-120%) and precision (≤18%), except for benzophenone (BP) and ethylhexyl 4-(dimethylamino) benzoate. Analysis of 100 marine invertebrate samples revealed detection frequencies of 100%, 98%, 89%, 64%, and 100% for BP, 4-hydroxybenzophenone, 4-methylbenzophenone, 4-methylbenzylidene camphor, and benzophenone-3 (BP-3), respectively. BP and BP-3 were detected at concentrations of 4.40-27.39 and < 0.020-0.560 ng/g w.w., respectively, indicating their widespread presence. Overall, our proposed method successfully detected UVACs in marine invertebrates, raising concerns regarding their potential environmental and health effects.

Exposure characteristics and cumulative risk assessment of bisphenol A and its substitutes: the Taiwan environmental survey for toxicants 2013.

Introduction: Ever since the use of bisphenol A (BPA) has been restricted, concerns have been raised regarding the use of its substitutes, such as bisphenol S (BPS) and bisphenol F (BPF). Meanwhile, the EU European Food Safety Authority (EFSA) issued the new tolerable daily intake (TDI) after the latest re-risk assessment for BPA, which enforced the need for cumulative risk assessment in the population. This study was conducted to identify BPA and its substitute's exposure characteristics of the general Taiwanese population and estimate the cumulative risk of bisphenol exposure. Methods: Urine samples (N = 366 [adult, 271; minor, 95]) were collected from individuals who participated in the Taiwan Environmental Survey for Toxicants 2013. The samples were analyzed for BPA, BPS, and BPF through ultraperformance liquid chromatography-tandem mass spectrometry. Daily intake (DI) levels were calculated for each bisphenol. Hazard quotients (HQs) were calculated with the consideration of tolerable DI and a reference dose. Additionally, hazard index (HI; sum of HQs for each bisphenol) values were calculated. Results: Our study found that the median level of BPA was significantly higher in adults (9.63 µg/g creatinine) than in minors (6.63 µg/g creatinine) (p < 0.001). The DI of BPS was higher in female (0.69 ng/kg/day) than in male (0.49 ng/kg/day); however, the DIs of BPF and BPS were higher in boys (1.15 and 0.26 ng/kg/day, respectively) than in girls (0.57 and 0.20 ng/kg/day, respectively). Most HI values exceeded 1 (99% of the participants) after EFSA re-establish the TDI of BPA. Discussion: Our study revealed that the exposure profiles and risk of BPA and its substitute in Taiwanese varied by age and sex. Additionally, the exposure risk of BPA was deemed unacceptable in Taiwan according to new EFSA regulations, and food contamination could be the possible source of exposure. We suggest that the risk of exposure to BPA and its substitutes in most human biomonitoring studies should be reassessed based on new scientific evidence.

Dietary risk assessment of benzophenone derivatives using bread consumption estimates in a Taiwanese population.

Listed as endocrine-disrupting chemicals, benzophenone (BP) and its nine analogues (BPs) are an emerging group of contaminants. The migration of BPs from ultraviolet inks to food has been investigated in many studies; however, few studies have investigated BPs in foods and the risks of human exposure to BPs. We validated a trace and multi-residue method for simultaneously determining 10 BPs, including BP, BP-1, BP-2, BP-3, BP-8, 4-MBP, 2-OHBP, 4-OHBP, M2BB, and PBZ. Eighty-one bread samples were analyzed using stable isotope labeling and ultrahigh-performance liquid chromatography-electrospray ionization tandem mass spectrometry with solid-liquid extraction. We determined the estimated daily intake of BPs, non-cancer risks, and lifetime cancer risks (LTCRs) from daily bread consumption for seven age groups using a Monte Carlo simulation. The method demonstrated robust linearity (R2 ≥ 0.991), low limits of detection (0.04-2 ng/g), and satisfactory precision. The intra- and interday relative standard deviation ranges were 0.6%-9% and 3%-20%, respectively. BP, 4-MBP, 2-OHBP, BP-1, and BP-3 were detected in 97%, 67%, 59%, 24%, and 23% of the samples, respectively. 2-OHBP had the highest mean (range) value of 18.3 (

Distribution and toxicity of submicron plastic particles in mice.

Although microplastics (MPs) have become a global issue, the biodistribution and toxicities of MPs were still unclear. In this study, c57BL/6 mice were treated with submicron-sized MPs labeled with Nile red fluorescence by oral gavage three times a week for four consecutive weeks. Flow cytometry and microscopy technique were used to examine the concentration and distribution of MPs in various tissues and biofluids. The oxidative stress and inflammation were assessed via liquid chromatography-mass spectrometry and enzyme-linked immunosorbent assay, respectively. Submicron-sized MP signals were found in the intestines, liver, spleen, kidney, lungs, blood, and urine of mice after MP exposure. Increased oxidative stress in mouse urine and elevated inflammatory cytokines in mouse kidney were also recorded. In conclusion, flow cytometry is a useful tool for examining the number concentrations of MPs. Increased oxidative stress and inflammation after MP treatment indicates that the toxicity of MP warrants further investigation.

Oxidative/nitrosative stress increased the risk of recurrent pregnancy loss-Taiwan Recurrent Pregnancy Loss and Environmental Study (TREPLES).

OBJECTIVE: Oxidative stress biomarkers (OSBs) may be strongly associated with disease progression and recurrent pregnancy loss (RPL). However, the research on associations of most OSBs (e.g., 8-nitroguanine [8-NO2Gua] and 4-hydroxy-2-nonenal-mercapturic acid [HNE-MA]) with RPL is limited. Therefore, we aimed to investigate the effect of OSBs exposure on RPL risk by performing a case-control study. MATERIAL AND METHODS: We use our established dataset, Taiwan Recurrent Pregnancy Loss and Environmental Study (TREPLES), which included 514 Taiwanese reproductive age women (aged 20-50 years; 397 cases and 117 controls) from National Cheng Kung University Hospital. RPL is clinically defined by a history of two or more consecutive miscarriages, where a miscarriage is defined as the termination of pregnancy before 20 weeks of gestation. The urinary levels of several OSBs (e.g., 8-hydroxy-2'-deoxyguanosine [8-OHdG], 8-NO2Gua, 8-isoprostaglandin F2α [8-isoPGF2α], and HNE-MA) and malondialdehyde (MDA) were measured using isotope dilution liquid chromatography-tandem mass spectrometry and thiobarbituric acid reactive substances, respectively. RESULTS: The median levels of 8-NO2Gua (6.15 vs. 3.76 ng/mL) and HNE-MA (30.12 and 21.54 ng/mL) were significantly higher in the RPL group than in the control group. By categorizing the OSBs data into tertiles, after we adjusted for age and urine creatinine levels discovered that the RPL risk associated with 8-NO2Gua and HNE-MA levels in the third tertile were approximately 2 times higher than those in the first tertile (8-NO2Gua, adjusted OR = 3.27, 95 % CI = 1.66-6.43; HNE-MA, adjusted OR = 1.96, 95 % CI = 1.05-3.64; p < 0.05). These findings suggest that the oxidative stress biomarkers of 8-NO2Gua and HNE-MA are risk factors for RPL. CONCLUSION: Our findings indicate that specific OSBs are associated with an increased RPL risk, suggesting that reducing OSB levels can improve RPL risk. Nevertheless, more studies on preventive medicine are required to understand the exposure sources and adverse outcome pathways of OSBs associated with RPL.

Data on lung and intestinal microbiome after air pollution exposure in ageing rats.

Air pollution has been linked to respiratory diseases, and urban air pollution can be attributed to a number of emission sources. The emitted particles and gases are the primary components of air pollution that enter the lungs during respiration. Particulate matter with an aerodynamic diameter of ≤ 2.5 µm (PM2.5) can deposit deep into the respiratory tract via inhalation and has been proposed as a causative agent for adverse respiratory health. In addition, the lung contains a diverse microbial community (microbiome) that maintains normal homeostasis and is significantly altered in a variety of pulmonary disorders. Air pollution, specifically PM2.5, has previously been shown to significantly alter the composition of the lower airway microbiome, which has been linked to decreased lung function in chronic obstructive pulmonary disease (COPD) patients. Surprisingly, the intestinal microbiome has also been implicated in the modulation of pulmonary inflammatory diseases. Therefore, dysbiosis of the lung and intestinal microbiomes pose significant negative effects on human health. This dataset describes the microbial community profiles of the lungs and intestines of ageing rats exposed to ambient unconcentrated traffic-related air pollution for three months. The whole-body exposure system was equipped with and without high efficiency particulate air (HEPA) filtration (gaseous vs. PM2.5 pollution). The data can provide valuable information on lung and intestinal microbiome changes, including that which was only found after traffic-related air pollution exposure.

Dispersive micro-solid phase extraction combined with gas chromatography-chemical ionization mass spectrometry for the determination of N-nitrosamines in swimming pool water samples.

A simple sample pretreatment technique, dispersive micro-solid phase extraction, was applied for the extraction of N-nitrosodimethylamine (NDMA) and other four N-nitrosamines (NAs) from samples of swimming pool water. The parameters affecting the extraction efficiency were systematically investigated. The best extraction conditions involved immersing 75 mg of carbon molecular sieve, Carboxen™ 1003 (as an adsorbent), in a 50-mL water sample (pH 7.0) containing 5% sodium chloride in a sample tube. After 20 min of extraction by vigorous shaking, the adsorbent was collected on a filter and the NAs desorbed by treatment with 150 µL of dichloromethane. A 10-µL aliquot was then directly determined by large-volume injection gas chromatography with chemical ionization mass spectrometry using the selected ion storage mode. The limits of quantitation were <0.9 ng/L. The precision for these analytes, as indicated by relative standard deviations, were <8% for both intra- and inter-day analyses. Accuracy, expressed as the mean extraction recovery, was between 62% and 109%. A preliminary analysis of swimming pool water samples revealed that NDMA was present in the highest concentration, in the range from n.d. to 100 ng/L.

Determining the trace-level photoinitiators in juices and milk from various types of packages in Taiwan by a micro-QuEChERS-based UPLC-MS/MS.

The distribution of 16 photoinitiators (PIs)-benzophenone (BP) and its five derivatives, 4-methylbenzophenone (4-MBP), methyl-2-benzoylbenzoate (M2BB), 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB), and the other 7 PIs-in packaged juice and milk was assessed using an UPLC-MS/MS with micro-QuEChERS. The validated method demonstrated robust linearity (≥0.9908), LOQs (juice: 0.006-7.26 ng/mL; milk: 0.004-7.14 ng/mL), intra- and inter-day accuracy (93.1%-110.1% for juice and 66.8%-114.6% for milk with relative standard deviations (RSDs) of ≤16.8%), and matrix effect with RSDs of ≤14.8%. BP exceeded the LOQ in 100% of 136 packaged juice (14.22 ± 7.60 ng/mL) and 51 milk (8.45 ± 3.25 ng/mL) samples, and the quantitation rates for M2BB and EHDAB in packaged juice were 100%. Notably, the 4-MBP in both juice and milk was significantly related to the packaging material. The method has been successfully applied to evaluate the occurrence and distribution of PIs in packaged juice and milk.