Maternal exposure to ambient SO2 and risk of polydactyly and syndactyly: a population-based case-control study in Liaoning Province, China

The changing epidemiology of syndactyly in Chinese newborns: a nationwide surveillance-based study

BACKGROUND

Little is known about the epidemiologic features of syndactyly (SD) in Chinese newborns.

METHODS

Using 2007-2019 data from the Chinese Birth Defects Monitoring Network, we conducted a prevalence analysis on overall, isolated and associated syndactyly according to birth year, maternal age, maternal residence, geographic region and infant sex, with special interests in time trends, perinatal outcomes and clinical phenotypes.

RESULTS

A total of 13,611 SD cases were identified among 24,157,719 births in the study period, yielding the prevalence of 5.63, 4.66 and 0.97 per 10,000 for overall, isolated, and associated SD, respectively. The prevalence of each type of SD exhibited an upward trend over the period. The prevalence of overall SD varied significantly by maternal residence (urban vs. rural, 6.69/10,000 vs. 4.35/10,000), maternal age (< 20 years, 5.43/10,000; 20-24 years, 5.03/10,000; 25-29 year, 5.65/10,000; 30-34 years, 6.07/10,000; ≥ 35 years, 5.76/10,000), geographic region (central, 5.07/10,000; east, 6.75/10,000; west, 5.12/10,000), and infant sex (male vs. female, 6.28/10,000 vs. 4.86/10,000). Newborns with associated SD were more likely to be born prematurely (29.2% vs. 10.6%) or with low birthweight (30.5% vs.9.8%) than those with isolated SD. The bilaterally, and unilaterally affected cases accounted for 18.4% and 76.7%, respectively. The feet were more frequently involved (64.3%) in those bilaterally affected cases, while right side preference (right vs left: 53.8% vs 46.2%) and upper limbs preference (hand vs foot: 50.8% vs 48.0%) were found in unilateral cases.

CONCLUSIONS

The prevalence of syndactyly in China is on the rise and notably higher than that in other Asian and European countries, highlighting the importance of investigating the etiology, epidemiology, and clinical implications of this condition in the Chinese population.

Maternal Exposure to Sulfur Dioxide and Risk of Omphalocele in Liaoning Province, China: A Population-Based Case-Control Study

Evidence of the association between maternal sulfur dioxide (SO₂) exposure and the risk of omphalocele is limited and equivocal. We aimed to assess the aforementioned topic during the first trimester of pregnancy. A population-based case-control study was carried out in infants consisting of 292 cases of omphalocele and 7,950 healthy infant controls. Exposure to SO₂, particulate matter with aerodynamic diameters ≤ 10 μm, and nitrogen dioxide was assessed by averaging the concentration from all stations in the mother's residential city. SO₂ exposure was categorized into three groups, with the lowest tertile defined as the reference category. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression models. Higher SO₂ exposure during the first trimester was significantly associated with omphalocele risk [per standard deviation (42 ug/m³) increment: OR = 1.39, 95% CI = 1.22–1.65]. When focusing on shorter exposure windows, similar positive associations were observed for SO₂ exposure in the first and third months of pregnancy. In addition, compared with the lowest tertile, high SO₂ exposure in the second month of pregnancy increased the risk of omphalocele (OR = 2.80, 95% CI = 1.61–4.97). Maternal exposure to SO₂ during the first trimester may increase the risk of omphalocele in offspring.

Maternal PM10 Exposure Increases Risk for Spina Bifida: A Population-Based Case-Control Study

Limited studies have focused on the impact of ambient air pollution on spina bifida. A population-based case-control study was conducted in Liaoning Province, China to assess the associations between maternal PM₁₀ exposures in various exposure windows and spina bifida risk. Data on spina bifida cases born between 2010 and 2015 were available from the Maternal and Child Health Certificate Registry of Liaoning Province. Controls were a random sample of healthy livebirths without any birth defects delivered in the selected five cities during 2010–2015. Ambient air monitoring data for PM₁₀ were obtained from 75 monitoring stations in Liaoning Province. The multivariable logistic regression models were established to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI). We further performed sensitivity analyses by using three propensity score methods. A total of 749 spina bifida cases and 7,950 controls were included. After adjusting for potential confounders, spina bifida was associated with a 10 μg/m³ increment in PM₁₀ during the first trimester of pregnancy (adjusted OR = 1.06, 95% CI: 1.00–1.12) and the 3 months before pregnancy (adjusted OR = 1.12, 95% CI: 1.06–1.19). The adjusted ORs in the final model for the highest vs. the lowest quartile were 1.51 (95% CI: 1.04–2.19) for PM₁₀ during the first trimester of pregnancy and 2.01 (95% CI: 1.43–2.81) for PM₁₀ during the 3 months before pregnancy. Positive associations were found between PM₁₀ exposures during the single month exposure windows and spina bifida. Sensitivity analyses based on two propensity score methods largely reported similar positive associations. Our findings support the evidence that maternal PM₁₀ exposure increases the risk of spina bifida in offspring. Further, validation with a prospective design and a more accurate exposure assessment is warranted.

Dynamic metabolism network simulation for energy-water nexus analysis: A case study of Liaoning Province, China

Faced with gradually serious energy and water crisis, the exploration of energy-water nexus metabolism relationships could provide a new direction for achieving the resources conservation and consumption reduction. In this paper, a comprehensive assessment for energy-water metabolic network is proposed to search the dynamic evolution and quantify the sectoral metabolic processes in Liaoning Province, China. Input-output analysis (IOA) and ecological network analysis (ENA) are integrated to clarify the embodied linkages and the complicated system interactions in the energy-water nexus network. The coefficients of "water-related energy" and "energy-related water" are explored through the system dynamics model (SDM) based on the consecutive input-output tables from 2012 to 2018. In addition, energy-water nexus efficiency index (EWEI) is constructed to evaluate the metabolism circulation efficiency of energy-water nexus network. The results indicate that (a) the energy and water outflow sectors mainly concentrate in primary industries and tertiary industries, while inflow sectors mainly concentrate in secondary industries; (b) the sectoral relationship provides effective pathways to implement collaborative resource saving and efficiency improvement measures, and the key sectors with the highest correlation with other sectors in energy-water nexus are AGR (agriculture), MIN (mining) and WRC (wholesale, retail and catering services). (c) the EWEI shows a gradually downward trend and the state of the energy system would determine the health of the energy-water nexus metabolism more strongly than water system.