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This study investigated hepatic oxidative damage in rats following long-term manganese (Mn) exposure and clarified the underlying mechanisms. Forty-eight rats (SPF, male) were randomly assigned to receive low (10 mg/kg, n = 16) or high doses of Mn (50 mg/kg, n = 16) or sterilized distilled water (control group, n = 16). Rats were euthanized after 12 months, and liver Mn levels and histopathological changes were determined. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and liver malondialdehyde (MDA), glutathione peroxidase (GSH-PX), nuclear factor E2-related factor-2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H quinine oxidoreductase-1 (NQO1) levels were also determined. The Mn concentration and relative liver weights were significantly higher in the high-dose Mn group than in the control and low-dose Mn exposure groups. Low-dose Mn exposure resulted in mild expansion of hepatic sinuses and intact nuclei, whereas high-dose exposure led to pathological alterations in hepatocytes. High-dose Mn treatment significantly increased AST, ALT, and MDA activities and decreased GSH-PX activity. Additionally, liver Nrf2, HO-1, and NQO1 protein expression were markedly reduced by Mn exposure. Under the study conditions, long-term low-dose Mn exposure resulted in slight pathological changes in liver structure, but high-dose Mn exposure affected both liver structure and function, which might be related to the inhibition of Nrf2 expression, suppression of the transcription of its underlying antioxidant genes, and down regulation of the corresponding proteins. Consequently, the antioxidant capacity in the rat liver was weakened. [ABSTRACT FROM AUTHOR]

Adult neurogenesis takes place in the brain subventricular zone (SVZ) in the lateral walls of lateral ventricles and subgranular zone (SGZ) in the hippocampal dentate gyrus (HDG), and functions to supply newborn neurons for normal brain functionality. Subchronic Mn exposure is known to disrupt adult neurogenesis in the SVZ. This study was designed to determine whether Mn exposure disturbed neurogenesis within the adult HDG. Adult rats (10 weeks old) received a single dose of bromodeoxyuridine (BrdU) at the end of 4-week Mn exposure to label the proliferating cells. Immunostaining and cell counting data showed that BrdU(+) cells in Mn-exposed HDG were about 37% lower than that in the control (p < .05). The majority of BrdU(+) cells were identified as Sox2(+) cells. Another set of adult rats received BrdU injections for 3 consecutive days followed by 2- or 4-week Mn exposure to trace the fate of BrdU-labeled cells in the HDG. The time course studies indicated that Mn exposure significantly reduced the survival rate (54% at 2 weeks and 33% at 4 weeks), as compared with that in the control (80% at 2 weeks and 51% at 4 weeks) (p < .01). A significant time-dependent migration of newborn cells from the SGZ toward the granule cell layer was also observed in both control and Mn-exposed HDG. Triple-stained neuroblasts and mature neurons further revealed that Mn exposure significantly inhibited the differentiation of immature neuroblasts into mature neurons in the HDG. Taken together, these observations suggest that subchronic Mn exposure results in a reduced cell proliferation, diminished survival of adult-born neurons, and inhibited overall neurogenesis in the adult HDG. Impaired adult neurogenesis is likely one of the mechanisms contribute to Mn-induced Parkinsonian disorder. [ABSTRACT FROM AUTHOR]

Decreased total testosterone (TT) is the recommended metric to identify age-related hypogonadism. However, average TT and the extent to which it varies by age, can vary substantially among different populations. Population-specific reference ranges are needed to understand normal versus abnormal TT levels. Therefore, the goal for this study was to describe androgen concentrations and their correlates among Western Chinese men. We completed a population-based, cross-sectional study including 227 young adults (YA) (20–39 years) and 939 older adults (OA) (40–89 years). We measured TT, sex-hormone binding globulin (SHBG), luteinizing hormone (LH), testosterone secreting index (TSI), and calculated free testosterone (cFT). Reference ranges for this population were determined using average YA concentrations. Multivariable regression models were used to predict hormone concentrations adjusting for age, waist-to-height ratio (WHR), marital status, education, occupation, smoking, alcohol, blood glucose, and blood pressure. Among OA, 3.8% had low TT, 15.2% had low cFT, 26.3% had low TSI, 21.6% had high SHBG, and 6.1% had high LH. Average cFT was significantly lower in OA (0.30 nmol/L; standard deviation (SD): 0.09) versus YA (0.37; SD: 0.11) but TT was not different in OA (16.82 nmol/L; SD: 4.80) versus YA (16.88; SD: 5.29). In adjusted models increasing age was significantly associated with increased SHBG or LH, and decreased cFT or TSI; however, TT was not significantly associated with age (β = 0.02 nmol/L; 95% confidence interval (CI): -0.01, 0.04). Higher WHR was associated with significantly decreased TT, SHBG, TSI, and LH. The only variable significantly related to cFT was age (β = -0.0033; 95% CI:-0.0037, -0.0028); suggesting that cFT measurements would not be confounded by other lifestyle factors. In conclusion, cFT, but not TT, varies with age in this population, suggesting cFT may be a better potential marker for age-related androgen deficiency than TT among Western Chinese men. [ABSTRACT FROM AUTHOR]

Aim: To develop a visual prediction model for gestational diabetes (GD) in pregnant women and to establish an effective and practical tool for clinical application. Methods: To establish a prediction model, the modelling set included 1756 women enrolled in the Zunyi birth cohort, the internal validation set included 1234 enrolled women, and pregnant women in the Wuhan cohort were included in the external validation set. We established a demographic–lifestyle factor model (DLFM) and a demographic–lifestyle–environmental pollution factor model (DLEFM) based on whether the women were exposed to environmental pollutants. The least absolute shrinkage and selection lasso–logistic regression analyses were used to identify the independent predictors of GD and construct a nomogram for predicting its occurrence. Results: The DLEFM regression analysis showed that a family history of diabetes (odd ratio [OR] 2.28; 95% confidence interval [CI] 1.05‐4.71), a history of GD in pregnant women (OR 4.22; 95% CI 1.89‐9.41), being overweight or obese before pregnancy (OR 1.71; 95% CI 1.27‐2.29), a history of hypertension (OR 2.61; 95% CI 1.41‐4.72), sedentary time (h/day) (OR 1.16; 95% CI 1.08‐1.24), monobenzyl phthalate (OR 1.95; 95% CI 1.45‐2.67) and Q4 mono‐ethyl phthalate concentration (OR 1.85; 95% CI 1.26‐2.73) were independent predictors. The area under the receiver operating curves for the internal validation of the DLEFM and the DLFM constructed using these seven factors was 0.827 and 0.783, respectively. The calibration curve of the DLEFM was close to the diagonal line. The DLEFM was thus the more optimal model, and the one which we chose. Conclusions: A nomogram based on preconception factors was constructed to predict the occurrence of GD in the second and third trimesters. It provided an effective tool for the early prediction and timely management of GD. [ABSTRACT FROM AUTHOR]

Epidemiological findings on the association between genital mycoplasma infection (GMI) and spontaneous abortion are inconsistent. Therefore, this meta-analysis aims to determine whether mycoplasma infection during pregnancy increases the risk of spontaneous abortion. An electronic database search was conducted using China National Knowledge Infrastructure, Elsevier, PubMed, SinoMed, The Cochrane Library, and Wanfang Database from database establishment to October 2021. Sixteen case–controls and 3 prospective cohorts were included. The meta-analysis showed that GMI was positively associated with spontaneous abortion (odds ratio (OR) 2.35, 95% confidence interval (CI) 1.50, 3.67). Of them, case–control studies showed that the GMI proportion in the spontaneous abortion group was higher than that in the normal group (OR 2.13, 95% CI 1.33, 3.43); the cohort study showed that the spontaneous abortion rate in the GMI group was higher than those in non-infected groups (relative risk 5.17, 95% CI 2.07, 12.95; risk difference 0.18, 95% CI 0.09, 0.27). Each outcome indicator was relatively robust in the sensitivity analysis, and no significant publication bias was found in the funnel plots. Our data support that GMI during pregnancy increases the risk of spontaneous abortion. Thus, the monitoring and timely treatment of GMI before pregnancy of GMI are essential to decrease the risk of spontaneous abortion. • Genital mycoplasma infection (GMI) increases the risk of spontaneous abortion (SA). • The type of GMI, the period of SA, and study location could be potential confounders. • Screening for GMI before pregnancy is essential to decrease the risk of SA. [ABSTRACT FROM AUTHOR]

Background: Beneficial effects of greenness on birth outcomes have been reported, but few studies have investigated the associations in both urban and non-urban settings. We aimed to evaluate and compare linear and nonlinear associations between greenness and birth outcomes in urban and non-urban settings.Methods: From October 2015 to December 2018, participants were recruited into the Maoming Birth Cohort Study. A total of 11 258 live birth records were obtained. Greenness exposure was assessed using the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI). Linear regression and nonlinear restricted cubic spline models were implemented to investigate the associations between greenness and birthweight, birth length, gestational age, preterm birth, low birthweight, small for gestational age and the potential for effect variation under urban or non-urban settings, after adjusting for covariates.Results: A 0.1-unit increase in NDVI-500m was significantly associated with an increase of 35.4 g in birthweight [95% confidence interval (CI): 13.2, 57.7], 0.15 cm in birth length (95% CI: 0.03, 0.26), 0.88 days in gestational age (95% CI: 0.05, 1.71) and lower odds of low birthweight [odds ratio (OR) = 0.69, 95% CI: 0.56, 0.85] and preterm birth (OR = 0.70, 95% CI: 0.58, 0.85). No association with head circumference was observed. For all outcomes, no significant linear associations were observed among non-urban dwellers. Inversed 'U-shaped' associations between greenness exposure and birth outcomes were observed in the total study population.Conclusions: Greenness exposure was associated with increased gestational age, birthweight and birth length in urban dwellers. Nonlinear associations assessed by restricted cubic splines suggested that health benefits could be larger when increasing greenness levels from low to medium compared with increasing greenness from medium to high levels. Further studies adopting nonlinear methods are warranted to verify our findings. [ABSTRACT FROM AUTHOR]

Sex hormone‐binding globulin, also known as testosterone–estradiol‐binding globulin, is a multifunctional protein synthesised by hepatocytes. Sex hormone‐binding globulin specifically binds and transports sex hormones to regulate plasma bioactive sex hormone levels and affects their bioavailability. As male sex hormone expression is dominated by testosterone, the binding of sex hormone‐binding globulin with testosterone leads to the reduction in bioavailable testosterone, which cannot fulfil its physiological roles, thereby resulting in male infertility, erectile and gonadal dysfunction, prostate cancer and other male reproductive system diseases. Sex hormone‐binding globulin may be involved in the pathogenesis of male reproductive system diseases, seriously affecting the quality of life of men. In this article, we review the association between sex hormone‐binding globulin and male reproductive system diseases. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) are a group of widely used chemicals and humans are exposed to them in their daily life. PBDEs exposure during pregnancy may have adverse effects on pregnant women and their fetuses. Nevertheless, limited information is available on the levels and determinants of PBDEs exposure in Chinese pregnant women. The internal exposure levels of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183, and 209) in placental samples of 1280 pregnant women from Zunyi birth cohort were analyzed using gas chromatography tandem mass spectrometry. All PBDEs concentrations were lipid adjusted (ng/g lw). Determinants of exposure were assessed by multivariable logistic regression model. Eight PBDE homologues were quantifiable in more than 70% of the samples. The highest median concentrations were found for BDE-209 (2.78 ng/g lw), followed by BDE-153 (1.00 ng/g lw) and BDE-183 (0.93 ng/g lw). The level of ΣPBDEs ranged from 0.90 to 308.78 ng/g lw, with a median concentration of 10.02 ng/g lw. Multivariate logistic regression analysis showed that maternal age older than 30 years old (OR: 1.59; 95% CI: 1.14, 2.23), pre-pregnancy obesity (1.51; 1.08, 2.10), home renovation within 2 years (1.43; 1.08, 1.91), spending more time outdoors during pregnancy (0.70; 0.55, 0.89), high consumption of fish/seafood (1.46; 1.13, 1.90) and eggs (1.44; 1.04, 2.00), male infant sex (1.69; 1.18, 2.42) were associated with PBDEs exposure. The study population is generally exposed to PBDEs, of which BDE-209 is the dominant congener, indicating extensive application of products containing deca-BDE mixtures. Maternal age, pre-pregnancy BMI, home decoration, average outdoor time during pregnancy, fish, seafood, eggs consumption, and fetal sex were exposure-determinning factors. This study contributes to the knowledge on region-specific PBDEs contamination in pregnant women and related risk factors. [Display omitted] • PBDEs remain ubiquitously present in pregnant women in Zunyi, Southwest China. • BDE-209 is the predominant homologue in human placenta. • PBDEs exposure significantly related with maternal age, BMI and fetal sex. • Increased exposure found in women with home decoration and less time outdoors. • Fish, seafood and eggs consumption significantly related with increased exposure. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that serum sex hormone-binding globulin (SHBG) levels increase with age; however, the causes remain unknown. The present study aimed to clarify whether the increase in SHBG levels is attributable to aging-related increases in SHBG synthesis. We examined and evaluated the association of serum SHBG levels with synthesis-related factors in men aged 18–80 years. Additionally, we examined the serum and liver levels of SHBG, hepatic nuclear factor 4α (HNF-4α), and peroxisome proliferator-activated receptor γ (PPAR-γ) in young, middle-aged, and old Sprague–Dawley rats. The study included 209 men in the young group (median age, 33 ± 10 years), 174 men in the middle-aged group (median age, 53 ± 8 years), and 98 men in the elderly group (median age, 71 ± 8 years). Serum SHBG levels increased with age (P < 0.05), whereas HNF-4α and PPAR-γ levels decreased with age (both P < 0.05). Compared with the findings in the young group, the average decline in HNF-4α levels was 2.61 % and 18.46 % in the middle-aged and elderly groups, respectively; the average decreases in PPAR-γ levels in these groups were 12.86 % and 20.76 %, respectively. The results in rats illustrated that liver SHBG and HNF-4α levels increased with age, whereas PPAR-γ and chicken ovalbumin upstream promoter-transcription factor (COUP-TF) levels decreased with age (all P < 0.05). Serum SHBG levels increased in rats with age, whereas HNF-4α and PPAR-γ levels decreased with age (all P < 0.05). The aging-related increased liver levels of the SHBG synthesis promoter HNF-4α and decreased levels of the SHBG inhibitory factors PPAR-γ and COUP-TF suggest that the aging-related increases in SHBG levels are associated with increased SHBG synthesis. • Sex hormone binding globulin (SHBG) is a key regulator of sex hormones. • The mechanism by which SHBG levels increase with age is unknown. • HNF-4α levels increased with age, whereas PPAR-γ and COUP-TF levels decreased. • SHBG levels appear to increase in aging because of increased synthesis. [ABSTRACT FROM AUTHOR]

Background: Fatigue is the most common symptom negatively affecting the quality of life of patients with cancer. The objective of the current study was to evaluate the preliminary efficacy and safety of 10.6-μm infrared laser moxibustion for cancer-related fatigue (CRF).Methods: The authors conducted a randomized, placebo-controlled trial among 78 patients with cancer who were diagnosed with CRF. The group treated with infrared laser moxibustion received 10.6 μm of infrared laser moxibustion on the ST36 (bilateral), CV4, and CV6 acupoints. Each participant received a 20-minute treatment session 3 times per week for 4 weeks. The sham group received the same treatment duration on the same acupoints, but without infrared laser output. The outcome was change in fatigue as measured by the Chinese version of the Brief Fatigue Inventory between groups at week 4 with additional evaluation at week 8 for durability of treatment effects. A mixed effects model was used to evaluate the difference in treatment effect over time.Results: Among those randomized, 61 patients (78%) completed the entire study. At the end of the intervention, the individuals in the group treated with the laser were found to have significantly less fatigue than those in the sham group (3.01 vs 4.40; P = .002). The improvement in fatigue persisted to week 8, favoring the group treated with laser moxibustion (3.03 vs 4.26; P = .006). Laser moxibustion was safe, with 3 cases of mild local erythema that resolved without medical intervention reported.Conclusions: Infrared laser moxibustion appeared to be safe and efficacious for improving CRF in a Chinese patient population. Larger studies in more racial/ethnically diverse populations are needed to confirm the benefit of this technique for fatigue in patients with cancer. Cancer 2016;122:3667-72. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. [ABSTRACT FROM AUTHOR]

Proper migration and invasion of extravillous trophoblast cells into the endometrium in early gestation is essential for successful embryo implantation. The development of nanotechnology has led to the emergence of nickel nanoparticles (Ni NPs), for which attendant health concerns are widespread. Ni NPs are known to affect reproduction and be embryotoxic, but whether they affect the migration and invasion functions of trophoblast cells is unclear. We investigated the effects of Ni NPs on the migration and invasion of HTR-8/SVneo in extravillous trophoblast cells and explored the possible role of the PI3K/AKT/MMP2 signaling pathway in this regard. Results showed that the migration and invasion of cells was significantly inhibited by the exposure of Ni NPs. The protein and mRNA levels of PI3K/AKT/MMP2 signaling pathway were significantly reduced with the increase in Ni NPs concentration. The presence of the PI3K activator 740Y-P partially attenuated the inhibition of cell migration and invasion by Ni NPs, confirming the involvement of this pathway. Thus, Ni NPs inhibit migration and invasion of human trophoblast HTR-8/SVneo cells by downregulating the PI3K/AKT/MMP2 signaling pathway. This study is important for the development of safety evaluation criteria for Ni NPs. [Display omitted] • Exposure to nickel nanoparticles (Ni NPs) significantly reduce the activity of HTR-8/SVneo cells. • Ni NPs inhibit the migration and invasion of trophoblast cells by inhibiting the PI3K/AKT/MMP2 pathway. • PI3K activator 740Y-P partially ameliorated the diminished migration/invasion ability of cells caused by Ni NPs. [ABSTRACT FROM AUTHOR]

Recent research attention has been paid to anthropogenic heat emissions (AE), temperature increase generated by human activity such as lighting, transportation, manufacturing, construction, and building climate controls. However, there is no epidemiological data available to investigate the association between anthropogenic heat emissions and metabolic syndrome (MetS), a cluster of conditions that increase risk of stroke, heart disease and diabetes. To explore the relationships between AE and MetS in China. We recruited 15,477 adults from the 33 Communities Chinese Health Study, a cross-sectional study in northeastern China. We retrieved anthropogenic heat flux by collecting socio-economic and energy consumption data as well as satellite-based nighttime light and Normalized Difference Vegetation Index datasets, including emissions from buildings, transportation, human metabolism, and industries. We also measured MetS components consisting of triglycerides, high density lipoprotein cholesterol, fasting glucose, systolic blood pressure, and diastolic blood pressure, and waist circumference. Restricted cubic spline models were applied to assess the associations between AE and MetS. The median flux of total AE was 30.98 W/m2 and industrial AE was the dominant contributor (87.64%). The adjusted odds ratio and 95% confidence interval (CI) of MetS for the 75th and 95th percentiles of the total AE against the threshold were 1.29 (95% CI: 1.21, 1.38) and 1.65 (95% CI: 1.47, 1.85). Greater AE was associated with higher odds of MetS in a dose-response pattern, and the lowest point of U-shape curve indicated the threshold effect. Participants who are young and middle-aged exhibited stronger associations between AE and MetS. Our novel findings reveal that AE are positively associated with MetS and that associations are modified by age. Further investigations into the mechanisms of the effects are needed. [ABSTRACT FROM AUTHOR]

Health effects of greenness perceived by residents at eye level has received increasing attention. However, the associations between eye-level greenness and respiratory health are unknown. The aim of the study was to investigate the associations between exposure to eye-level greenness and lung function in children. From 2012 to 2013, a total of 6740 school children in seven cities in northeast China were recruited into this cross-sectional study. Forced expiratory volume in 1 s (FEV 1), forced vital capacity (FVC), peak expiratory flow rate (PEF), and maximum mid expiratory flow rate (MMEF) were measured to evaluate lung function and to define lung impairment. Eye-level greenness was extracted from segmented Tencent Map street view images, and a corresponding green view index (GVI) was calculated. Higher GVIs mean more greenness coverage. Mixed-effects logistic regressions were used to estimate the health effects on lung impairment per interquartile range (IQR) increase in GVI. Linear regressions were used to estimate the associations between GVI and lung function. The health effects of ambient air pollutants were also assessed, including particulate matter with an aerodynamic diameter <1.0 μm (PM 1), <2.5 μm (PM 2.5), <10 μm (PM 10) as well as nitrogen dioxide (NO 2). An increase of GVI 800m was associated with lung impairment in FEV 1 , FVC, PEF and MMEF, with ORs ranging from 0.68 (95% CI: 0.59, 0.79) to 0.83 (95% CI: 0.74, 0.93). The associations between an IQR increase of GVI 800m and FEV 1 (48.15 ml, 95% CI: 30.33–65.97 ml), FVC (50.57 ml, 95% CI: 30.65–70.48 ml), PEF (149.59 ml/s, 95% CI: 109.79–189.38 ml/s), and MMEF (61.18 ml/s, 95% CI: 31.07–91.29 ml/s) were significant, and PM 1 , PM 2.5 , and PM 10 were found to be mediators of this relationship. More eye-level greenness was associated with better lung function and reduced impairment. However, eye-level greenness associations with lung function became non-significant once lower particulate matter air pollution exposures were considered. • More eye-level greenness exposure is associated with better lung function. • The associations became non-significant once lower particulate matter air pollution exposures were considered. • Greenness may serve as an index for a reduction of other factors in open space. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) exposure has been linked to diabetes, but evidence on the association of isomers of PFAS with type 2 diabetes (T2D) remains scant. This population based cross-sectional study aimed to investigate associations between serum PFAS isomers, glucose-homeostasis markers and T2D, adjusted for multiple potential confounders. We used data from "Isomers of C8 Health Project in China" from July 2015 to October 2016. A total of 10 PFAS including isomers of PFOS and PFOA were measured in serum of 1045 Chinese adults. Fasting blood glucose, fasting insulin, homeostasis model of insulin (HOMA-IR) and beta cell function (HOMA-β) were considered as markers of glucose-homeostasis. We found significant positive associations between serum PFAS isomers and glucose-homeostasis markers, namely, fasting blood glucose, fasting insulin and HOMA-IR. Per log-unit increase in branched (br)-PFOS concentration was associated with increased fasting blood glucose (β = 0.25, 95% CI: 0.18, 0.33), fasting insulin (β = 2.19, 95% CI: 1.44, 2.93) and HOMA-IR (β = 0.69, 95% CI: 0.50, 0.89). As compared to br-PFOS, linear (n)-PFOS and -PFOA showed lesser significant associations with glucose-homeostasis makers. Further, exposure to all PFAS including isomeric PFOS, PFOA and PFHxS increased the risk of T2D with br-PFOS exhibiting the highest risk (OR = 5.41, 95% CI: 3.68–7.96). The associations were stronger among women than men. In conclusion, chronic exposure to PFAS isomers was associated with impaired glucose-homeostasis and may increase the prevalence of T2D in Chinese adults. Given the ubiquity of PFAS in the environment and the public health burden of T2D, future studies are warranted to corroborate the findings. [Display omitted] • Environmental exposure may play a role in pathogenesis of type 2 diabetes (T2D). • Serum concentrations of PFAS isomers altered glucose homeostasis in Chinese. • Exposure to PFAS isomers were also associated with an increased risk of T2D in adults. • The associations were stronger for branched PFOS than linear PFOS. • The associations were stronger in women than men. [ABSTRACT FROM AUTHOR]

The potential association between coal-burning arsenic exposure and type 2 diabetes (T2D) was examined through a case control study, conducted in coal-burning arsenic poisoning areas in the Guizhou Province. This study included patients diagnosed with type 2 diabetes. Control subjects without type 2 diabetes were recruited randomly after gender and age 1:1 matching. All subjects completed questionnaire surveys and underwent physical examination and whole blood arsenic level testing. The whole blood arsenic level was associated with a significant increase in the risk of type 2 diabetes (75th versus 25th, adjusted OR = 1.76, 95% CI: 1.03–3.01). However, a nonlinear relationship was observed between the blood arsenic level and type 2 diabetes. The risk of type 2 diabetes increased with blood arsenic levels above 3.69 μg/L (Log As ≥0.57). The subgroup analysis revealed that blood arsenic levels were associated with significantly increased risk of type 2 diabetes in people who ever smoked (P <.05), particularly those who smoked ≥15 years (adjusted OR = 3.15, 95% CI: 1.9–7.28). Therefore, prolonged arsenic exposure, even at a low level, is associated with a higher prevalence of type 2 diabetes in a nonlinear pattern. Blood arsenic levels less than 3.69 μg/L may be considered safe with respect to the risk of T2D. However, smoking, particularly smoking ≥15 years, may be associated with the development of diabetes in patients with arsenic exposure. • Coal-burning arsenic exposure is associated with T2D. • Prolonged arsenic exposure, is associated with T2D in a nonlinear pattern. • Smoking may be associated with T2D onset in patients with arsenic exposure. [ABSTRACT FROM AUTHOR]