title: Assessing and mapping spatial associations among oral cancer mortality rates, concentrations of heavy metals in soil, and land use types based on multiple scale data.
abstract: In this study, a deconvolution procedure was used to create a variogram of oral cancer (OC) rates. Based on the variogram, area-to-point (ATP) Poisson kriging and p-field simulation were used to downscale and simulate, respectively, the OC rate data for Taiwan from the district scale to a 1 km × 1 km grid scale. Local cluster analysis (LCA) of OC mortality rates was then performed to identify OC mortality rate hot spots based on the downscaled and the p-field-simulated OC mortality maps. The relationship between OC mortality and land use was studied by overlapping the maps of the downscaled OC mortality, the LCA results, and the land uses. One thousand simulations were performed to quantify local and spatial uncertainties in the LCA to identify OC mortality hot spots. The scatter plots and Spearman's rank correlation yielded the relationship between OC mortality and concentrations of the seven metals in the 1 km cell grid. The correlation analysis results for the 1 km scale revealed a weak correlation between OC mortality rate and concentrations of the seven studied heavy metals in soil. Accordingly, the heavy metal concentrations in soil are not major determinants of OC mortality rates at the 1 km scale at which soils were sampled. The LCA statistical results for local indicator of spatial association (LISA) revealed that the sites with high probability of high-high (high value surrounded by high values) OC mortality at the 1 km grid scale were clustered in southern, eastern, and mid-western Taiwan. The number of such sites was also significantly higher on agricultural land and in urban regions than on land with other uses. The proposed approach can be used to downscale and evaluate uncertainty in mortality data from a coarse scale to a fine scale at which useful additional information can be obtained for assessing and managing land use and risk.
authors.affiliation: Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Da-an District, Taipei City 106, Taiwan. B97602046@ntu.edu.tw.
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Lin
authors.affiliation: Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Da-an District, Taipei City 106, Taiwan. yplin@ntu.edu.tw.
authors.forename: Yu-Pin
authors.initials: YP
authors.lastname: Lin
authors.affiliation: Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Da-an District, Taipei City 106, Taiwan. beckyycwang@gmail.com.
authors.forename: Yung-Chieh
authors.initials: YC
authors.lastname: Wang
authors.affiliation: Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Da-an District, Taipei City 106, Taiwan. tknchang@ntu.edu.tw.
authors.forename: Tsun-Kuo
authors.initials: TK
authors.lastname: Chang
authors.affiliation: Department of Civil and Disaster Prevention Engineering, National United University, 2 Lien-Da, Nan-Shih-Li, Miaoli 36003, Taiwan. lchiang@nuu.edu.tw.
authors.forename: Li-Chi
authors.initials: LC
authors.lastname: Chiang
mesh_terms: D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D008297:Male; D019216:Metals, Heavy / Q000633:toxicity*; D009062:Mouth Neoplasms / Q000209:etiology / Q000401:mortality*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000633:toxicity*; D062206:Spatial Analysis; D013624:Taiwan / Q000453:epidemiology
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants