Relationship between lifespan indicators and elemental background values: A case study in Guangdong Province, China

Epidemiological characteristics of centenarian deaths in China during 2013-2020: A trend and subnational analysis

BACKGROUND

Studies that comprehensively address the characteristics of centenarian deaths are rare. The present study aimed to depict the characteristics of centenarian deaths in China and their changing trends.

METHODS

Data on centenarian deaths between 2013 and 2020 were obtained from the national mortality surveillance system of China, including date, place of death (PoD), and underlying cause of death (CoD). Descriptive analyses were performed to understand the epidemiological characteristics, and a joinpoint regression model was adopted to examine the changing trends in the proportions of different PoDs, CoDs among centenarians, and centenarian deaths accounting for all deaths and deaths among people aged 65 years and older.

RESULTS

There were 46,938 registered centenarian deaths between 2013 and 2020 that included 34,311 females (73.10%) and 12,627 males (26.90%). January (12.05%), February (9.99%), and December (9.74%) were the top three months with the highest number of deaths. The proportions of deaths that occurred in homes, hospitals, and nursing homes were 81.71%, 13.63%, and 2.68%, respectively. The proportion of deaths in nursing homes increased by 9.60% (95% confidence intervals [CIs], 6.4-12.9%) from 2014 to 2020. Heart disease (35.72%) was the leading cause of death, followed by respiratory diseases (17.63%), cerebrovascular disease (15.60%), and old age (11.22%). The proportion of respiratory diseases decreased by 4.8% (95% CI, -8.8 to -0.7%), and the proportion of deaths from old age decreased by 2.3% (95% CI, -4.4 to -0.1%) per year. Shanghai had the highest proportions of deaths in hospitals (39.38%) and nursing homes (14.68%). Sichuan had the highest proportion of deaths attributed to respiratory diseases (32.30%), while Jiangsu (26.58%) and Zhejiang (23.61%) had the highest proportions of deaths from old age.

CONCLUSION

Unlike other countries, centenarian deaths in China are characterized by a higher proportion of home and heart disease deaths, and this death pattern differs across provinces.

Hydrochemical characteristics and water quality assessment of natural water in the South China Mountains: the case in Lianzhou

South China Mountain Region has a well-developed water system with the most abundant water in China. Untreated natural water is the main source of drinking water for the local people. This study aimed to investigate the hydrochemical characteristics and trace element concentrations of natural water in the mountainous regions of South China. In this study, 116 water samples were collected. Traditional hydrochemical methods, water quality index (WQI), hazard index (HI), and nutrient speciation of trace elements (NSTE) were used for analysis. In general, the hydrochemical type was mainly Ca-HCO3- type. The hydrochemical characteristics were mainly influenced by the weathering of calcite and silicate rocks. Overall total dissolved solids (TDS) were low, indicating mainly soft and very soft water. The water that met the standards for mineral water had an average concentration of 59.69 mg/L for Sr (strontium) and an average concentration of 0.46 mg/L for H2SiO3 (silicic acid). Although the water quality index (WQI) indicated that 91.3% of the water samples in the study area were of good quality (WQI < 25), 2.58% of the water samples had significant non-carcinogenic risk (HI > 1) due to the high As and Pb concentrations. The water in the study area contributed significantly to human intake of Sr, Cr, and V, accounting for 8.4, 8.3, and 7.7% of the required daily intake for adults, respectively. It is recommended that a comprehensive water quality evaluation system be constructed to ensure that mountain water is managed for development and safe to drink.

Concentrations of heavy metals in water, sediments and aquatic organisms from a closed realgar mine

Mining activities can result in severe heavy metal contamination in freshwater ecosystems and lead to significant health risks. In this study, eight heavy metal concentrations in the water, sediments and aquatic organisms, including eighteen fish species, two shrimp species, one crab species and one amphibian frog species of the abandoned Shimen Realgar Mine area, were analysed. The results showed that most of the heavy metals detected in water, sediments and fish from the mine area were at relatively high levels, and historical realgar mining activities were a major source of arsenic (As) contamination in this area. We concluded that heavy metal bioaccumulation is species- and tissue-specific and is different for each element and sampling site. The concentration of heavy metals in fish was generally lower than that of the other aquatic organism species; these concentrations varied among different species with different feeding habits and habitats. The study showed that heavy metal concentrations were lower in muscle tissue than in other tissues (e.g. liver, skin, exoskeleton). A significant positive correlation between the As concentrations in sediment and fish was observed, indicating that sediment is an important factor affecting As accumulation in fish; thus, for fish protection, controlling the sources of water and sediment contamination is essential. Furthermore, the estimated daily intake (EDI) of all metals was acceptable, and the corresponding target hazard quotient (THQ) and total target hazard quotient (TTHQ) values were less than 1; hence, there was no serious health risk through fish consumption in this area.

Vertical distribution and major influencing factors of soil selenium in tropical climate: A case study of Chengmai County, Hainan Island

Soil selenium is of great significance to human health. Soil-forming parent rocks are the most critical factor that influences soil Se levels. Chengmai County, Hainan Island, has a tropical climate and diverse types of parent rocks, in which soil Se content is high. This study investigated the vertical distribution of soil Se from various parent rock substrates under tropical climatic conditions, and the factors that influence these soil Se contents, with 69 vertical soil profiles covering Chengmai County. The vertical distribution of soil Se and correlations with CIA (chemical alteration index), Al₂O₃, TFe₂O₃ (total iron oxide expressed as Fe₂O₃), total iodine, SOC (soil organic carbon), and pH were analysed. As per the results, the mean ± standard error of Se content in the A, B, and C horizons was 0.88 ± 0.13 mg/kg, 0.77 ± 0.08 mg/kg and 0.45 ± 0.05 mg/kg, respectively. The parent rock strictly controlled the horizon distribution of Se in the A-horizon. Soil Se showed A-B-horizons-enrichment in the vertical profile, especially in soil profiles overlying granite and basalt. It is hypothesised that the Se enriched in soils developed from the Tuolie Formation due to the release of Se from the weathering process of Se-rich rocks. Meanwhile, Se in soils developed from granite and basalt is more closely associated with exogenous input. Another crucial factor for the high level of Se in Chengmai County is the tropical climate, which has led the rocks to generally undergo intense chemical weathering. This results in soils rich in clay minerals and Fe/Al oxyhydroxides, which easily absorb and retain Se. Furthermore, the Se content of the B-horizon was generally higher than that of the A-horizon due to leaching. These results provide further knowledge and understanding of the geochemical behaviour of soil Se and guide the evaluation of Se-rich land resources under tropical climatic conditions.

Spatial heterogeneity of human lifespan in relation to living environment and socio-economic polarization: a case study in the Beijing-Tianjin-Hebei region, China

The spatial heterogeneity and influence factors of public lifespan have been reported worldwide at the national level or typical longevous areas. However, few sub-national studies considering the living environment and socio-economic level together have been explored in the imbalanced developed region with a huge population base and deteriorated air quality. In this paper, spatial heterogeneity of lifespan integrating environment and socio-economic influence factors was investigated in the Beijing-Tianjin-Hebei (BTH) region of China using geographically weighted regression (GWR). Five indicators were constructed to determine the lifespan based on the three national censuses (1990-2010) in the BTH region. The results showed that the areas with higher CH (centenarians per 100,000 inhabitants) and centenarity index (CI) exhibited changing distribution in the BTH region, whereas those with lower CH and CI and extreme value of the ultra-octogenarian index (UOI) and LI (> 90/ > 65) maintained a relatively stable feature through time. But as lifespan indicators increase overall, the differences between the counties/districts widen. Furthermore, remarkable spatial heterogeneity was detected for the associations between the significant environmental and socio-economic variables and lifespan indicators. Although the natural geographic condition (altitude) still exhibited a negative influence on the longevity of the population, the socio-economic factors (GDP_pc and income level) showed a more dominant influence on the extension of the elderly and longevity population. Correspondingly, the widened unbalance of population lifespan (UOI, LI, CH) was considered closely related to the socio-economic polarization, and the adverse effects of air pollution on life expectancy at birth (LEB) have also emerged. To further improve the overall lifespan level and narrow the lifespan gap in the BTH region, future work on cleaner air and more balanced development is still needed.

Differences of selenium and other trace elements abundances between the Kaschin-Beck disease area and nearby non-Kaschin-Beck disease area, Shaanxi Province, China

In order to find out the environmental geochemical characteristics of KBD affected area, KBD and non-KBD villages in KBD Counties, Weibei KBD area, Shaanxi Province, China were studied. Contents of Se and other elements in soil, wheat, maize and drinking water were analyzed. The results show that soil of Weibei KBD area is deficient in trace elements comparing with BSC and non-KBD area. Wheat of Weibei KBD area is deficient both in major elements and trace elements comparing with REC. Wheat of KBD village is especially deficient in Cr, Co, Se, Mo and Mg. Contents of Sr, Li and Mo in wheat of KBD village are significantly lower than nearby non-KBD village, but the average Se content is slightly higher. The deficiency of trace elements, especially Se, Sr, Li and Mo in staple food and trace elements in soil, is the main characteristic for the environment of KBD area.

Quantitative assessment on soil concentration of heavy metal-contaminated soil with various sample pretreatment techniques and detection methods

Detection and quantification of heavy metals in soil samples are significant in terms of environmental monitoring and risk assessment for metals. In order to improve the accuracy and precision to detect heavy metal, in this study, four standard samples (NASS-4, NASS-5, NASS-9, and NASS-16) were analyzed by evolving heating (electric heating plate, water bath, and microwave) and acidic systems (includes HCl, HNO₃, HF, and HClO₄). The result shows that different pretreatment methods have different effects on the extraction of heavy metal elements and five heavy metal elements (Cu, Zn, Pb, Ni, and Cr) were selected for optimization through pretreatment methods. Although the contents of heavy metals were same but we found diversity in the results. Under optimal conditions, the selected standard samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and atomic absorption spectroscopy (AAS), and the results were compared. The results show that different elements have their own most suitable detection methods, such as for Pb, the most suitable method is ICP-MS; and for Zn, the most suitable method is AAS. Pretreatment methods and detection techniques are combined to find and improve accuracy of results for certain elements. This study provides a reliable detection method for the accurate detection of heavy metals in the environment.