Mixed metals in the cropped lands in central Taiwan contaminated about 230 ha. According to the Soil and Groundwater Protection Remediation Act (SGWR Act) of Taiwan, these lands were restored. However, some grains of paddy rice grown in these remediated soils still contained more than 0.5 mg Cd kg(-1), which the Department of Health of Taiwan notified as the maximum allowable Cd content in rice. The suitability of planting edible crops in these soils is now in doubt. Brassica rapa is the crop most often sold in Taiwan's market and is planted in the interval between the first and second stages of planting of paddy rice, especially in central Taiwan where this experiment was conducted. A pot experiment was conducted using soils contaminated artificially with Cd or both Cd and Pb. The soil was then amended with 5% of biosolid and followed by planting of B. rapa. The objectives were to study the effect of biosolid amendment on the soil and the interaction between Cd and Pb on the growth of and Cd accumulation in B. rapa. Experimental result showed that the biomass and the accumulation of Cd by B. rapa were significantly increased in the biosolid-amended soils compared with the control. Lead has a synergistic effect on enhancing the accumulation of Cd by B. rapa grown in artificially Cd-contaminated soils

Measured concentrations of five metallic elements (Cr, Cu, Zn, Cd and Pb) during August 2013 to July 2014 at three sites in central Taiwan were analyzed for identifying source regions and seasonal and site variations. Air mass backward trajectory analysis suggested that pollution sources were mainly from southern Taiwan and Philippine seashore areas during the spring and summer, from Korea, Japan and Hainan during the fall, and from northern China and Hong Kong during the winter. Biomass burning activities in south East Asia in spring were believed to have contributed a significant amount to the measured high elements concentrations. Two-way Analysis of variance was conducted to identify the significance of differences in measured elements concentrations between element species, season and sites. Significant differences between elements were identified at all the three sites with exceptions for Cr and Pb at the Airport site. Season differences were significant at two of the three sites; but site to site differences were found to be insignificant. The elements pollution levels in central Taiwan were in medium to high ranges in East Asia.

This study characterized and discussed particulate ambient air particulate concentrations and seasonal variations for PM18, PM10, PM2.5, and PM1 during June 2013-July 2013 at this traffic sampling site. In addition, this study also characterized the ambient air particulates size distributions by using MOUDI-100S4 sampler to collect 1-day the ambient suspended particles (PM18, PM10, PM2.5, and PM1) at this sampling site. In addition, the study also showed that the main pollutants contributions were from traffic and residual areas. As for the pollutants seasonal concentrations variations, the results indicated that the average particle concentrations orders were all displayed as daytime > nighttime for PM18, PM10, PM2.5 and PM1 at this characteristic sampling site. The results further indicated that the mean highest of metal concentrations in this study indicated that the average metal concentration were all displayed as Mn > Cr > Ni > Pb > Cd for PM18, PM10, PM2.5 and PM1 on daytime and nighttime at this characteristic sampling site.

The purpose of this study is to characterize metallic elements associated with atmospheric particulate matter in the dry deposition plate, total suspended particulate, fine particles, and coarse particles at Taichung Harbor and Gong Ming Junior High School (airport) in central Taiwan at a sampling site from June 2013 to August 2013. The results indicated that: (1) the average concentrations of the metallic elements Cr and Cd were highest at the Gong Ming Junior High School (airport), and the average concentrations of the metallic elements Ni, Cu, and Pb were highest at the Taichung Harbor sampling site. (2) The high smelting industry density and export/import rate of heavily loaded cargos were the main reasons leading to these findings. (3) The average metallic element dry deposition and metallic element PM(2.5-10) all followed the order of Pb > Cr > Cu > Ni > Cd at the two sampling sites. However, the average metallic elements Cu and Pb were found to have the highest dry deposition velocities and concentrations in PM(2.5) for the two sampling sites in this study. (4) The correlation coefficients of ambient air particle dry deposition and concentration with wind speed at the airport were higher than those from the harbor sampling site. The wind and broad open spaces at Taichung Airport were the possible reasons for the increasing correlation coefficients for ambient air particle concentration and dry deposition with wind speed at the Taichung Airport sampling site.