Urinary para-nitrophenol levels of pregnant women and cognitive and motor function of their children aged 2 years: Evidence from the SMBCS (China)

Urinary concentrations of environmental phenol among pregnant women in the Japan Environment and Children's Study

Humans are exposed to various bisphenols, alkylphenols and nitrophenols through dietary intake, food packaging and container materials, indoor and outdoor air/dust. This study aimed to evaluate exposure of Japanese pregnant women to environmental phenols by measuring target compounds in urine samples. From a cohort of the Japan Environment and Children's Study, 4577 pregnant women were selected. Bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), bisphenol AF (BPAF), para-nitrophenol (PNP), 3-methyl-4-nitrophenol (PNMC), branched 4-nonylphenol (4-NP), linear 4-nonylphenol and 4-tert-octylphenol (4-t-OP) were analysed using a high-performance liquid chromatograph coupled to a triple-quadrupole mass spectrometer. The urinary metabolite data were combined with a questionnaire to examine the determinants of phenol exposure by machine learning. The estimated daily intake (EDI) and hazard quotient (HQ) of BPA were calculated. PNP (68.2%) and BPA (71.5%) had the highest detection frequencies, with median concentrations of 0.76 and 0.46 μg/g creatinine, respectively. PNMC, BPS, BPF and 4-NP were determined in 24.9%, 11.9%, 1.3% and 0.4% of samples, respectively, whereas BPAF (0.02%) and 4-t-OP (0.02%) were only determined in a few samples. The PNP concentrations measured in this study were comparable with those reported in previous studies, whereas the BPA concentrations were lower than those reported previously worldwide. The EDI of BPA was 0.014 μg/kg body weight/day. Compared with the tolerable daily intake set by the German Federal Institute for Risk Assessment, the median (95th percentile) HQ was 0.044 (0.2). This indicates that the observed levels of BPA exposure pose a negligible health risk to Japanese pregnant women. Determinants of bisphenol and nitrophenol exposure could not be identified by analysing the questionnaire solely, suggesting that biological measurement is necessary to assess exposure of pregnant women to bisphenols and nitrophenols. This is the first study to report environmental phenol exposure of Japanese pregnant women on a nationwide scale.

Association between organophosphorus insecticides exposure and the prevalence of sleep problems in the US adults: An analysis based on the NHANES 2007-2018

OBJECTIVE

The aim of this study was to evaluate the association between organophosphorus pesticides (OPPs) exposure and sleep problems.

METHODS

In this study, data from 6295 participants aged 18 years or older were collected from the National Health and Nutrition Examination Survey (NHANES). The dialkyl phosphate compounds (DAPs) metabolites, OPPs exposure biomarker, were examined using solid phase extraction-high coupled with isotope dilution-ultrahigh performance liquid chromatography-tandem mass spectrometry. Data on short sleep duration (SSD), self-reported trouble sleeping and self-reported sleep disorder were collected from the database. Weighted generalized logistic model, weighted quantile sum (WQS) model, and quantile-based g calculation (QGC) methods were used for analyzing the collected data.

RESULTS

The prevalence of SSD, self-reported trouble sleeping and self-reported sleep disorder in this study were 28.91 % (1814/6274), 25.31 % (1593/6294), and 9.05 % (289/3195), respectively. After confounding factors adjustments, the prevalence of SDD in participants with high log-transformed DETP, DMTP, DEDTP, and DMDTP were 1.19 times (OR: 1.11-1.28, P < 0.001), 1.09 times (OR: 1.03-1.15, P = 0.003), 1.26 times (OR: 1.17-1.37, P < 0.0001), and 1.10 times (OR: 1.04-1.17, P = 0.003) than in participants with low showed, respectively. A non-linear relationship was noted between SSD with the urinary concentration of DEP (P for nonlinearity < 0.001), DMP (P for nonlinearity < 0.001), DMTP (P for nonlinearity = 0.006), and DMDTP (P for nonlinearity = 0.001). The WQS results showed that the prevalence of SDD was 1.28 times (95 % CI: 1.17-1.40, P < 0.001) higher in participants with high co-exposure to OPPs than in those with low co-exposure, with DEDTP having the enormous weights (0.50). The QGC results also revealed a significant positive association between the co-exposure of DAPs and SSD (OR: 1.08, 95 % CI:1.02-1.16, P = 0.01) with DETP having the most positive weight (0.44). As for the association between DAPs with self-report sleep disorder, only DEP was detected that it was positively associated with self-reported sleep disorder with all confounding factors adjusted (OR: 1.17; 95 % CI: 1.07-1.29, P = 0.001). However, all DAPs have not detected a significant association with the prevalence of self-reported trouble sleeping. Besides, there was no significant association between co-exposure to OPPs with self-reported trouble sleeping and self-reported sleep disorder.

CONCLUSION

The results of this study indicated that high levels of single or mixture urinary DAP, indicating for OPPs exposure, were associated with an increased prevalence of SSD in general adults, which has significant implications for preventing OPPs pollution and protecting sleep health.