Ji-Hyock Yoo

Transfer Factor of Heavy Metals from Agricultural Soil to Agricultural Products

BACKGROUND: The Transfer Factor (TF) of heavy metals from soil to plant is important, because TF is an indicator of heavy metal in soils and a factor that quantifies bioavailability of heavy metals to agricultural products. This study was conducted to investigate the transfer ability of Arsenic (As), Cadmium (Cd), and Lead (Pb) from soil to agricultural products. METHODS AND RESULTS: We investigated heavy metals (As, Cd and Pb) concentrations in 9 agricultural products (rice, barely, corn, pulse, lettuce, pumpkin, apple, pear, tangerin) and soil. TF of agricultural products was evaluated based on total and HCl-extractable soil concentration of As, Cd, and Pb. Regression analysis was used to predict the relationship of total and HCl-extractable concentration with agricultural product contents of As, Cd, and Pb. The result showed that TF was investigated average 0.006~0.309 (As), 0.002~6.185 (Cd), 0.003~0.602 (Pb). The mean TF value was the highest as rice 0.309 in As, lettuce 6.185, pear 0.717, rice 0.308 in Cd, lettuce 0.602, pumpkin 0.536 in Pb which were dependent on the vegetable species and cereal is showed higher than fruit-vegetables in As. CONCLUSION(S): Soil HCl-extractable concentration of As, Cd, and Pb had the larger effects on thier contents in agricultural products than total soil concentrations. We suggests that TF are served as influential factor on the prediction of uptake. Further study for uptake and accumulation mechanism of toxic metals by agricultural products will be required to assess the human health risk and need TF of more agricultural products.

Chemical Composition and Heavy Metal Contents in Commercial Liquid Pig Manures

Heavy metal concentration as well as chemical composition were surveyed in commercial liquid pig manure to provide the basic information for mitigation research of hazardous material to agro-product. Seventy-five samples of liquid pig manure were collected and analyzed from 2009 to 2010 nationwide. Average contents of T-N, , and were 0.29%, 0.08%, and 0.11%, respectively. The contents of heavy metals ranged from 0.001~0.083 for As, 0.001~0.108 for Cd, 0.002~0.495 for Cr, 0.07~47.8 for Cu, ND~0.005 for Hg, 0.035~1.033 for Ni, ND~0.291 for Pb, and for Zn, respectively. It was noted that among 75 samples, only four samples exceeded the Zn guideline () of liquid fertilizer derived from livestock manure but others were not exceeded the regulation.

Arsenic Contamination of Polished Rice Produced in Abandoned Mine Areas and Its Potential Human Risk Assessment using Probabilistic Techniques

BACKGROUND: This study was conducted to investi- gate the arsenic (As) contaminations in polished rice culti- vated nearby abandoned mine areas, and to estimate the potential health risk through dietary intake of As-enriched polished rice in each age-gender population. METHODS AND RESULTS: The As contents in poli- shed rice grown fifteen abandoned mine areas were analy- zed. The average daily intake (ADD) as well as probabili- stic health risk were estimated by assuming probability distribution of exposure parameters. The average total As concentration in polished rice was 0.09±0.06 mg/kg with a range of 0.02~0.35 mg/kg. For health risk assessment, the ADD values in all age-gender populations did not exceed the provisional tolerable daily intake (PTDI) of 2.1 µg/kg b.w./day for inorganic As. Cancer risk probability (R) values were 2.45~3.28×10 -4 and 2.51~5.75×10 -4 for all age population and gender population, respectively. Particularly, the R value, 5.75×10 -4 , for children less than six years old were estimated to be high. Hazard quotient (HQ) values were 0.23~0.31 and 0.11~0.33 for general population and age-gender population, respectively. CONCLUSION(s): The average R values assessed via intake of polished rice cultivated in abandoned mine areas exceeded the acceptable cancer risk of 10 -6 ~10 -4 for regula- tory purpose. Considering the HQ values smaller than 1.0, potential non-cancer toxic effects may not be caused by the long-time exposure through intake of As-contaminated polished rice.

Model Development for Estimating Total Arsenic Contents with Chemical Properties and Extractable Heavy Metal Contents in Paddy Soils

This study was performed to estimate total contents of arsenic (As) by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines. The soil was collected from paddies near abandoned mines. Soil pH, electrical conductively (EC), organic mater (OM), available phosphorus (), and exchangeable cations (Ca, K, Mg, Na) were measured. Total contents of As and extractable contents of metals were analyzed by ICP-OES. From stepwise analysis, it was showed that the contents of extractable As, available phosphorus, extractable Cu, exchangeable K, exchangeable Na, and organic mater significantly influenced the total contents of As in soil (p) + 0.334 Log (extractable-Cu) + 0.186 Log (exchangeable-K) - 0.593 Log (exchangeable-Na) + 0.558 Log (OM). The estimated value in total contents of As was significantly correlated with the measured value in soil (=0.84196, p

Monitoring of Heavy Metals in Agricultural Soils from Consecutive Applications of Commercial Liquid Pig Manure

Monitoring of Heavy Metals in Agricultural Soils from Consecutive Applications of Commercial Liquid Pig Manure Woo-Ri Go, Ji-Young Kim, Ji-Hyock Yoo, Ji-Ho Lee, Anitha Kunhikrishnan, Jeong-Mi Lee, Kye-Hoon Kim, Doo-Ho Kim and Won-Il Kim (Chemical Safety Division, National Academy of Agricultural Science, Suwon 441-707, Korea, Saemangeum Regional Environmental Office, National Institute Environment Research, Jeonju 560-870, Korea, Department of Environmental Horticulture, The University of Seoul, Seoul 130-743, Korea)

Monitoring and Risk Assessment of Heavy Metals in Edible Mushrooms

BACKGROUND: Many edible mushrooms are known to accumulate high levels of heavy metals. This research was focused on health risk assessment to investigate the mushrooms in Korea, arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) contaminations in edible mushrooms in cultivated areas were investigated, and health risk was assessed through dietary intake of mushrooms. METHODS AND RESULTS: The heavy metals in mushrooms were analyzed by ICP/MS after acid digestion. Probabilistic health risk were estimated by Monte-Carlo simulation techniques. The average contents of As, Cd, Pb, and Hg were mg/kg, mg/kg, mg/kg, and mg/kg, respectively. The results showed that contents of Cd and Pb did not exceed maximum residual levels established by European Uion regulation (Cd 0.20 mg/kg and Pb 0.30 mg/kg). For health risk assessment, estimated intakes in all age populations did not exceed the provisional tolerable daily intake of As and Hg, provisional tolerable monthly intake of Cd, provisional tolerable weekly intake of Pb. The Hazard Index (HI) were ranged from for As, for Cd, for Pb, and for Hg at general population. CONCLUSION: The HI from the ratio analysis between daily exposure and safety level values was less than 1.0. This results demonstrated that human exposure to heavy metals through dietary intake of mushrooms might not cause adverse effect.

Monitoring and Risk Assessment of Cadmium and Lead in Agricultural Products

BACKGROUND: This study was conducted to investigate the agricultural product (Pulses, Lettuces, Pumpkins, Apples, Pears and Tangerines) in Korea, monitoring of cadmium (Cd) and lead (Pb) contaminations of agricultural products in cultivated areas and abandoned mine areas were investigated, and risk assessment was performed through dietary intake of agricultural products. METHODS AND RESULTS: The average contents of Cd and Pb ranged from 0.001 to 0.018 mg/kg and from 0.007 to 0.032 mg/kg respectively. The result was showed that contents of Cd and Pb did not exceed maximum residual levels established by CODEX except pumpkins and apples. The average daily intake were in the range of to b.w./day at the mean and 95th percentile for Cd, to b.w./day at the mean and 95th percentile for Pb for general population, based on the Korean public nutrition report 2008. The Hazard Index (HI) from the ratio analysis between daily exposure and safety level values was smaller than 1.0. CONCLUSION(s): This results demonstrated that human exposure to Cd and Pb through dietary intake of agricultural produces from abandoned mine areas might not cause adverse effect exceeding to those from non-contaminated areas.

Monitoring of Cd, Hg, Pb, and As and Risk Assessment for Commercial Medicinal Plants

BACKGROUND: The current study was carried out to investigate Cd, Hg, Pb and As contaminations in 222 commercial medicinal plants and to estimate the potential health risk through dietary intake of commercial medicinal plants in Korea.METHODS AND RESULTS: The Cd, Hg, Pb, and As in medicinal plants were analyzed by ICP/MS and mercury analyzer.The potential health risk was estimated using risk assessment tools. Total amount of Cd in medicinal plants with 29% samples exceeded the standard limit legislated in `Pharmaceutical Affairs Act` while all plant samples were lower than the standard limit value for As, Hg, and Pb. However, when applying the standard limit for root vegetable (fresh weight) in the Food Sanitation Act, four samples exceeded the standard limit of Pb. For health risk assessment, the values of cancer risk probability were 0.3~5.9×10-7which were less than the acceptable cancer risk of 10-6~10-4for regulatory purpose. Also, Hazard quotientvalues were lower than 1.0.CONCLUSION: Therefore, these results demonstrated that human exposure to Cd, Hg, Pb, and As through dietary intake of commercial medicinal plants might notcause adverse health effects although some medicinal plants were higher than the standard limit values for Cd and Pb.

Assessment of health risk associated with arsenic exposure from soil, groundwater, polished rice for setting target cleanup level nearby abandoned mines

This study focused on health risk assessment via multi-routes of As exposure to establish a target cleanup level (TCL) in abandoned mines. Soil, ground water, and rice samples were collected near ten abandoned mines in November 2009. The As contaminations measured in all samples were used for determining the probabilistic health risk by Monte-Carlo simulation techniques. The human exposure to As compound was attributed to ground water ingestion. Cancer risk probability (R) via ground water and rice intake exceeded the acceptable risk range of 10-6 ~ 10-4 in all selected mines. In particular, the MB mine showed the higher R value than other mines. The non-carcinogenic effects, estimated by comparing the average As exposure with corresponding reference dose were determined by hazard quotient (HQ) values, which were less than 1.0 via ground water and rice intake in SD, NS, and MB mines. This implied that the non-carcinogenic toxic effects, due to this exposure pathway had a greater possibility to occur than those in other mines. Besides, hazard index (HI) values, representing overall toxic effects by summed the HQ values were also greater than 1.0 in SD, NS, JA, and IA mines. This revealed that non-carcinogenic toxic effects were generally occurred. The As contaminants in all selected mines exceeded the TCL values for target cancer risk (10-6) through ground water ingestion and rice intake. However, the As level in soil was greater than TCL value for target cancer risk via inadvertent soil ingestion pathway, except for KK mine. In TCL values for target hazard quotient (THQ), the As contaminants in soil did not exceed such TCL value. On the contrary, the As levels in ground water and polished rice in SD, NS, IA, and MB mines were also beyond the TCL values via ground water and rice intake. This study concluded that the health risks through ground water and rice intake were greater than those though soil inadvertent ingestion and dermal contact. In addition, it suggests that the abandoned mines to exceed the risk-based TCL values are carefully necessary to monitor for soil remediation.

A Study on the Factors Causing Analytical Errors through the Estimation of Uncertainty for Cadmium and Lead Analysis in Tomato Paste

BACKGROUND: This study aimed to estimate the mea- surement uncertainty associated with determination of cadmium and lead from tomato paste by ICP/MS. The sources of measurement uncertainty (i.e. sample weight, final volume, standard weight, purity, molecular weight, working standard solution, calibration curve, recovery and repeatability) in associated with the analysis of cadmium and lead were evaluated. METHODS AND RESULTS: The guide to the expre- ssion of uncertainty was used for the GUM (Guide to the expression of Uncertainty in Measurement) and Draft EURACHEM/CITAC (EURACHEM: A network of organization for analytical chemistry in Europe/ Co-Operation on International Traceability in Analytical Chemistry) Guide with mathematical calculation and statistical analysis. The uncertainty components were evaluated by either Type A or Type B methods and the combined standard uncertainty were calculated by statistical analysis using several factors. Expected un- certainty of cadmium and lead was 0.106±0.015 mg/kg (k=2.09) and 0.302±0.029 mg/kg (k=2.16), on basis of 95% confidence of Certified Reference Material (CRM) which was within certification range of 0.112±0.007 mg/kg for cadmium (k=2.03) and 0.316±0.021 mg/kg for lead (k=2.01), respectively. CONCLUSION(s): The most influential components in the uncertainty of heavy metals analysis were confirmed as recovery, standard calibration curve and standard solution were identified as the most influential compo- nents causing uncertainty of heavy metal analysis. Therefore, more careful consideration is required in these steps to reduce uncertainty of heavy metals ana- lysis in tomato paste.