Source-oriented stochastic health risk assessment of toxic metals in soil via a hybrid model and Monte Carlo simulation.

Toxic metal contamination in soils poses significant hazards to the environment and human health; thus, quantitative assessment of the sources and risks of metal contaminants are urgently needed. A hybrid model that integrates the positive matrix factorization (PMF) and random forest (RF) methods was proposed to quantify the sources of toxic metals in soils by combining diverse environmental variables (source proxies) in this study. In addition, a health risk assessment and Monte Carlo simulations were integrated to estimate the source-oriented stochastic health risk.

Different "nongrain" activities affect the accumulation of heavy metals and their source-oriented health risks on cultivated lands.

"Nongrain" production on cultivated land is one of the primary environmental issues in China. Different "nongrain" activities may introduce different pollution sources to the local environment, leading to variations in heavy metal contents in soil, which can profoundly impact national food security. In this study, three typical "nongrain" regions (Nanxun (NX), Xiaoshan (XS) and Lin'an (LA)) with intensive aquaculture, tea planting and flower (seedling) growth on cultivated land around the Hangzhou metropolitan area were selected to address the spatial heterogeneity of accumulation levels, sources and source-oriented health risks of heavy metals in soil.

Quantitative heterogeneous source apportionment of toxic metals through a hybrid method in spatial random fields.

Toxic metals in soils pose hazards to food security and human health. Accurate source apportionment provides foundation for pollution prevention. In this study, a novel hybrid method that combines positive matrix factorization, Bayesian maximum entropy and integrative predictability criterion is proposed to provide a new perspective for exploring the heterogeneity of pollution sources in spatial random fields.

Processing toxic metal source proxies appropriately for better spatial heterogeneity source apportionment.

Soil toxic metals have strong spatial heterogeneity, and their sources vary among regions. Thus, this study integrated the Catreg and geographically weighted regression (GWR) models to quantitatively extract the main source proxies (numerical and categorical variables were analyzed simultaneously) for different toxic metals and analyze the spatial heterogeneity of the distributions of these sources. Pb, Cd and Hg were the predominant toxic metals in soil.

Pollution threshold assessment and risk area delineation of heavy metals in soils through the finite mixture distribution model and Bayesian maximum entropy theory.

Pollution threshold and high-risk area determination for heavy metals is important for effectively developing pollution control strategies. Based on heavy metal contents in 3627 dense samples, an integrated framework combining the finite mixture distribution model and Bayesian maximum entropy (BME) theory was proposed to assess pollution thresholds, contamination levels and risk areas in an uncertain environment for soil heavy metals. The results showed that the average heavy metal contents were in the order Zn > Cr > Pb > Cu > Ni > As > Cd > Hg, with strong/moderate variation, and the corresponding pollution thresholds were 158.

Contamination assessment, health risk evaluation, and source identification of heavy metals in the soil-rice system of typical agricultural regions on the southeast coast of China.

To quantitatively assess heavy metal accumulation and potential ecological and human health risks as well as analyze the sources of metals in a typical soil-rice system located on the southeast coast of China, 120 topsoil samples and corresponding rice grain samples were collected across the study area. The concentrations of As, Cd, Pb, Cr, Hg, Zn, Cu, and Ni were analyzed. The results revealed that Hg, Cd, and Cu were the main pollutants in soils.

Contamination assessment and source apportionment of heavy metals in agricultural soil through the synthesis of PMF and GeogDetector models.

Heavy metal pollution in soils has attracted great attention worldwide in recent decades. Selecting Hangzhou as a case study location, this research proposed the synthesis application of positive matrix factorization (PMF) and GeogDetector models for quantitative analysis of pollution sources, which is the basis for subsequent soil pollution prevention and remediation. In total, 2150 surface soil samples were collected across the study area.

Identifying the sources and spatial patterns of potentially toxic trace elements (PTEs) in Shanghai suburb soils using global and local regression models.

Destructive development of suburban areas in some metropolises has exposed suburban soils to high risk of potentially toxic trace elements (PTEs) enrichment, which also threatens human and ecosystem health. This study investigated the pollution status, sources and spatial patterns of four PTEs (Pb, Cd, Cr and As) in 1805 soil samples collected from the suburbs of Shanghai in 2015. Nineteen potential sources, including: 6 soil property factors, 10 proximity factors and 3 topography factors, were selected to help explain the PTEs aggregation using logistic regression models from global and local perspectives.

Improved heavy metal mapping and pollution source apportionment in Shanghai City soils using auxiliary information.

Soil heavy metal pollution can be a serious threat to human health and the environment. The accurate mapping of the spatial distribution of soil heavy metal pollutant concentrations enables the detection of high pollution areas and facilitates pollution source apportionment and control. To make full use of auxiliary soil properties information and show that they can improve mapping, a synthesis of the Bayesian Maximum Entropy (BME) theory and the Geographically Weighted Regression (GWR) model is proposed and implemented in the study of the Shanghai City soils (China).

The association between heavy metal soil pollution and stomach cancer: a case study in Hangzhou City, China.

Stomach cancer (SC) is a severe health burden, with nearly half of the world's cases found in China. Noticeably, the emissions of heavy metals into the environment have increased alongside rapid urbanization and industrialization in China. However, as regards carcinogenic associations, the relationship between heavy metals and SC is yet unclear.

The spatio-temporal distribution and risk factors of thyroid cancer during rapid urbanization-A case study in China.

Background: Incidences of thyroid cancer (TC) have been increasing worldwide in recent decades. In this research, we aimed to analyze the spatiotemporal pattern of TC and explore relevant environmental risk factors in Hangzhou (HZ), which is rapidly urbanizing and home to the highest TC incidence in China.

Methods: Spatial scan statistic was employed to analyze the spatiotemporal pattern of TC in HZ from 2008 to 2012.

[Geographic spatial pattern of digestive system cancers in Yiwu city].

Objective: To analyze the geographic spatial patterns and risk areas of main digestive system cancers in Yiwu city.

Methods: Newly diagnosed cases of esophageal, gastric and colorectal cancer during 2010-2014 were obtained from Yiwu Center for Disease Control and Prevention (CDC). The household registration population data in 2013 were obtained from public security bureau.

Contribution of industrial density and socioeconomic status to the spatial distribution of thyroid cancer risk in Hangzhou, China.

Background: The thyroid cancer (TC) incidence in China has increased dramatically during the last three decades. Typical in this respect is the case of Hangzhou city (China), where 7147 new TC cases were diagnosed during the period 2008-2012. Hence, the assessment of the TC incidence risk increase due to environmental exposure is an important public health matter.

Improving Spatiotemporal Breast Cancer Assessment and Prediction in Hangzhou City, China.

Breast cancer (BC) is the main cause of death of female cancer patients in China. Mainstream mapping techniques, like spatiotemporal ordinary kriging (STOK), generate disease incidence maps that improve our understanding of disease distribution. Yet, the implementation of these techniques experiences substantive and technical complications (due mainly to the different characteristics of space and time).

Soil Landscape Pattern Changes in Response to Rural Anthropogenic Activity across Tiaoxi Watershed, China.

Soil sealing (loss of soil resources due to extensive land covering for the purpose of house building, road construction etc.) and subsequent soil landscape pattern changes constitute typical environmental problems in many places worldwide. Previous studies concentrated on soil sealing in urbanized regions, whereas rural areas have not been given sufficient attention.

Spatiotemporal Co-existence of Female Thyroid and Breast Cancers in Hangzhou, China.

Thyroid and breast cancers (TC, BC) are common female malignant tumors worldwide. Studies suggest that TC patients have a higher BC risk, and vice versa. However, it has not been investigated quantitatively if there is an association between the space-time TC and BC incidence distributions at the population level.

[Hierarchical regionalization for spatial epidemiology: a case study of thyroid cancer incidence in Yiwu, Zhejiang].

Objective: Sporadic cases occurring in mall geographic unit could lead to extreme value of incidence due to the small population bases, which would influence the analysis of actual incidence.

Methods: This study introduced a method of hierarchy clustering and partitioning regionalization, which integrates areas with small population into larger areas with enough population by using Geographic Information System (GIS) based on the principles of spatial continuity and geographical similarity (homogeneity test). This method was applied in spatial epidemiology by using a data set of thyroid cancer incidence in Yiwu, Zhejiang province, between 2010 and 2013.

A Geographic Analysis about the Spatiotemporal Pattern of Breast Cancer in Hangzhou from 2008 to 2012.

Background: Breast cancer (BC) is the most common female malignant tumor. Previous studies have suggested a big incidence disparity among different cities in China. The present work selected a typical city, Hangzhou, to study BC incidence disparity within the city.

Urban-rural disparity of breast cancer and socioeconomic risk factors in China.

Breast cancer is one of the most commonly diagnosed cancers worldwide. The primary aim of this work is the study of breast cancer disparity among Chinese women in urban vs. rural regions and its associations with socioeconomic factors.

[Reappraisal of the impacts of human Runt-related transcription factor gene 3 expression on differentiation and prognosis of gastric cancer].

Objective: To investigate the expression of Runt-related transcription factor gene 3(RUNX3) in gastric cancer and its impact on the outcome of gastric cancer patients.

Methods: By using immunohistochemistry staining and western blot assay, the expression of RUNX3 protein in 66 cases of gastric cancer with various clinicopathologic characteristics were detected, and the effects of RUNX3 protein expression on the outcome of patients undergone surgical resection were evaluated.

Results: (1) The expression rate of RUNX3 protein in gastric cancer lesions was 60.

Applying proteomic methodologies to analyze the effect of methionine restriction on proliferation of human gastric cancer SGC7901 cells.

Background: Methionine dependence is a feature unique to cancer cells, exhibited as inability to grow in a methionine-depleted environment supplemented with homocysteine, the immediate metabolic precursor of methionine. However, the molecular mechanisms by which methionine restriction inhibits cancer cells growth have not been elucidated. The effect of methionine restriction on the protein expression in gastric cancer cells was studied.

Methionine-dependence and combination chemotherapy on human gastric cancer cells in vitro.

Aim: To elucidate whether human primary gastric cancer and gastric mucosa epithelial cells in vitro can grow normally in a methionine (Met) depleted environment, i.e. Met-dependence, and whether Met-depleting status can enhance the killing effect of chemotherapy on gastric cancer cells.

A study of preoperative methionine-depleting parenteral nutrition plus chemotherapy in gastric cancer patients.

AIM:To investigate the interference of methionine-free parenteral nutrition plus 5-Fu (-MetTPN+5-Fu) in gastric cancer cell kinetics and the side effects of the regimen.METHODS:Fifteen patients with advanced gastric cancer were randomly divided intotwo groups, 7 patients were given preoperatively a seven-day course of standard parenteral nutrition in combination with a five-day course of chemotherapy (sTPN+5-Fu), while the other 8 patients were given methionine-deprived parenteral nutrition and 5-Fu (-MetTPN+5-Fu). Cell cycles of gastric cancer and normal mucosa were studied by flow cytometry (FCM).