Health risk assessment of PM2.5 heavy metals in county units of northern China based on Monte Carlo simulation and APCS-MLR.

The key areas of China's urbanization process have gradually shifted from urban areas to county-level units. Correspondingly, air pollution in county towns may be heavier than in urban areas, which has led to a lack of understanding of the pollution situation in such areas. In view of this, 236 PM2.5 filter samples were collected in Pingyao, north of the Fen-Wei Plain, one of the most polluted areas in China. Monte Carlo simulation was used to solve the serious uncertainties of traditional HRA, and the coupling technology of absolute principal component score-multiple linear regression (APCS-MLR) and health risk assessment (HRA) is used to quantitatively analyze the health risks of pollution sources. The results showed that PM2.5 concentration was highest in autumn, 3.73 times the 24 h guideline recommended by the World Health Organization (WHO). Children were more susceptible to heavy metals in the county-level unit, with high hazard quotient (HQ) values of Pb being the dominant factor leading to an increased non-carcinogenic risk. A significant carcinogenic risk was observed for all groups in autumn in Pingyao, with exposure to Ni in the outdoor environment being the main cause. Vehicle emissions and coal combustion were identified as two major sources of health threats. In short, China's county-level population, about one-tenth of the world's population, faces far more health risks than expected.

Pollution effect assessment of industrial activities on potentially toxic metal distribution in windowsill dust and surface soil in central China.

Boundaries between industrial and urban areas in developing countries are not clearly defined, but pollution effect assessment of industrial activities on potentially toxic metal (PTM) distribution in these areas has rarely been investigated. Fifteen villages and eight communities surrounding the industrial areas from Anyang, China, were chosen as research objects in this study. A total of 78 windowsill dust and 78 surface soil samples were collected to determine the pollution levels, spatial distribution and risk indices of nine PTMs. PTM concentrations (expect Cr, Mn and Ni in surface soil) in the surveyed region were higher than the local soil background values. Amongst these PTMs, serious Cd and As pollution was discovered, and Cd and As in windowsill dust and surface soil exceeded the background value by 73.00 and 9.59, 9.74 and 10.92 times, respectively. Compared with the Igeo in surface soil, a large degree of variation in Igeo for the different PTMs was found in windowsill dust. The interpolated spatial distribution of dust Cr, Zn, Pb, Cd and soil Mn, Ni and Cu had a gradually decreasing pollution trend from the south to the north due to the prevailing wind directions in winter in the study area. Results of multivariate statistics reflected that industrial production and traffic emission affected the concentration of PTMs in windowsill dust and surface soil. The non-carcinogenic risks for children (soil: 12.4; dust: 19.2) were larger than those for adults (soil: 1.02; dust: 1.51). This finding suggested that industrial activities caused serious harm to the residents around industrial areas.

Boys, Girls, and Grandparents: The Impact of the Sex of Preschool-Aged Children on Family Living Arrangements and Maternal Labor Supply.

In this study, we consider household decision-making on living arrangements and maternal labor supply in extended families with young children. In such a context, decision-making is driven by the concerns that the companionship of children is a household public good and that family members share childcare and related domestic duties. The incentive to share children's companionship is affected by son preference, whereas the economic motive of labor division hinges on the potential wage rate of the mother. Both channels play important roles in households with mothers whose wage rates are high, while sharing the companionship of (grand) sons is the main driving force in households with mothers whose wage rates are low. Using China Health and Nutrition Survey (CHNS) data, we find that among less-educated mothers, the incidence of a family coresiding with the paternal grandmother is at least 8.6 percentage points higher if the firstborn is a boy. At the same time, maternal labor supply increases by 2.9 days per month. By contrast, for educated mothers, the propensity for coresidence is higher, the working hours are longer, and the impact of the child's sex is not significant. Our study not only provides a better understanding of the demographic and economic factors determining coresidence and intrahousehold time allocations but also lends empirical support to policies aiming to increase female labor supply and improve the well-being of girls.

The Impact of Social Pensions on Intergenerational Relationships: Comparative Evidence from China.

China launched a new rural pension scheme (hereafter NRPS) for rural residents in 2009, now covering almost all counties with over 400 million people enrolled. This implementation of the largest social pension program in the world offers a unique setting for studying the economics of intergenerational relationships during development, given the rapidity of China's population aging, traditions of filial piety and co-residence, decreasing number of children, and dearth of formal social security, at a relatively low income level. We draw on rich household surveys from two provinces at distinct development stages - impoverished Guizhou and relatively well-off Shandong - to better understand heterogeneity in the impact of pension benefits. Employing a fuzzy regression discontinuity design, we find that around the pension eligibility age cut-off, the NRPS significantly reduces intergenerational co-residence, especially between elderly parents and their adults sons; promotes pensioners' healthcare service consumption; and weakens (but does not supplant) non-pecuniary and pecuniary transfers across three generations. These effects are much larger in less developed Guizhou province.