Abandoned Metal Mine Areas Research Articles

Association between levels of exposure to heavy metals and renal function indicators of residents in environmentally vulnerable areas

Abandoned metal mines and refineries are considered environmentally vulnerable areas owing to high levels of exposure to heavy metals. This study examined the association between heavy metal exposure and renal function indicators. We studied a total of 298 participants, of which 74 and 68 resided in low- and high-exposure abandoned metal mine areas, respectively, with 121 in the refinery area and 35 in the control area. Blood and urine samples were collected from the participants to analyze the levels of blood lead, cadmium, and creatinine and urinary cadmium, NAG, and β2-MG. The estimated glomerular filtration rate, which is calculated using the Chronic Kidney Disease Epidemiology Collaboration equation, was used for assessments. The study participants comprised more females than males, and their mean age was 70.3 years. The blood lead and cadmium as well as urinary cadmium levels were 2.12 μg/dL, 1.89 μg/L, and 2.11 μg/L, respectively, in the heavy metal-exposure areas, and 1.18 μg/dL, 0.89 μg/L, and 1.11 μg/L, respectively, in the control area. The odds ratio (OR) for exceeding the reference value showed that blood cadmium in the refinery area was 38 times higher than that in the control area. Urinary cadmium was seven times higher in the low-exposure abandoned metal mine area than in the control area. NAG showed a positive correlation with urinary cadmium in all areas. In the refinery area, correlations were observed between β2-MG and urinary cadmium levels and the eGFR and blood cadmium level; in the high-exposure abandoned metal mine area, correlations were observed between NAG, β2-MG, and the eGFR and blood cadmium. In this study, the association between Cd exposure and some renal function indicators was observed. This study’s findings and the obtained biological samples can serve as a basis for future molecular biological research.

Assessment of Heavy Metal Exposure to Residents around Abandoned Metal Mines

TPS 621: Exposure to metals, Johan Friso Foyer, Floor 1, August 26, 2019, 3:00 PM - 4:30 PM Background/Aim: Abandoned metal mines are areas of great concern for the health effects of residents due to hazardous substances such as heavy metals. The purpose of this study was to compare the exposure of heavy metals to residents of the abandoned metal mines and general population through National Health Survey. Methods: We examined 4,499 residents of the abandoned mines of 2nd phase health effects survey of abandoned metal mines (AMS, ‘13~’17). We used data from the Korea national health and nutrition examination survey (KNHANES, ‘12, ‘13, ‘16) and the Korean national environmental health survey (KNEHS ‘09~’15). Based on the gender and age distribution of AMS, KNHANES (n=980) and KNEHS (n=1,412) were randomly sampled for the same distribution. The geometric mean concentrations (95% confidence interval) of blood lead, blood cadmium, urinary cadmium, and urinary arsenic concentration were presented, the excess proportion was given by reference to the 95th percentile concentration of the general population. Results: The geometric mean concentration of lead in blood was significantly higher in AMS than those of the general population (AMS: 2.27(2.24-2.30)a μg/dL; KNHANES: 2.11(2.06-2.17)b μg/dL; KNEHS: 2.23(2.18-2.29)b μg/dL; p<0.001). The geometric mean concentration of blood cadmium in AMS was also higher than those of the general population (AMS: 1.42(1.40-1.44) μg/L; KNHANES: 1.24(1.20-1.28) μg/L; p<0.001), and cadmium in urine was remarkably different and statistically significant (AMS: 1.47(1.42-1.53) μg/L; KNEHS: 0.47(0.45-0.49) μg/L; p<0.001). Conclusions: The concentration of heavy metals in residents of the abandoned metal mines was higher than those of the general population. We considered the routes of exposure of crops ingestion, groundwater intake, soil contact, and inhalation of scattered dust in contaminated environment. Therefore, continuous individual and national management are needed to evaluate the health risks of residents in the abandoned metal mine areas.

폐금속광산 지역 농작물섭취경로의 인체위해도 산정을 위한 생물농축계수와 토양분석방법에 관한 연구

폐금속광산 지역 농작물섭취경로의 인체위해도 산정을 위한 생물농축계수와 토양분석방법에 관한 연구

국내 두 폐금속 광산의 중금속오염 인체위해성평가 비교

This study was conducted to propose the methodology of human risk assessment specialized to domestic mine areas and to quantify the human risk of heavy metal (As, Cd, Cu, Pb, and Zn) contamination around two abandoned metal mines. To attain the goals, we established a relevant exposure scenario, including 7 exposure pathways and extracted a variety of exposure factors reflecting the characteristics of inhabitants around abandoned metal mine areas. Finally, carcinogenic and non-carcinogenic risks were compared between two areas, exposure pathways, heavy metal contaminants, and receptors. The total excess carcinogenic risks of two mine areas of concern were calculated to be larger than the acceptable carcinogenic risk (), indicating those two areas are not safe for carcinogenic hazard. In addition, the hazard indices of two areas were computed to be higher than unit risk (1), suggesting that the areas of concern have non-carcinogenic risk. Ingestion of crop and intake of groundwater were evaluated to be main exposure pathways contributing to carcinogenic and non-carcinogenic risks within the areas. Also, the results show that carcinogenic and non-carcinogenic hazards were mostly attributed to As and As, Cd, and Pb, respectively.

Pedogenesis in mine tails affects macroporosity, hydrological properties, and pollutant flow

Mining activities take a direct impact on the environment, particularly when this activity is focused on metal-ore exploitation. Abandoned metal mine areas contain different types of residues from ore-processing operations that are typically characterized by high concentrations of heavy metals. One consequence is the generation of acid-mine drainage, caused by the oxidation and hydrolysis of metal sulphides. Mine tail soils have been studied under several points of view, but not on how crack formation affects their properties and functioning, before irreversible hardening. The Cartagena–La Union mining district is one of the more ancient Spanish mining regions. This region is placed at the south-eastern part of Spain, and contains one of the largest lead and zinc ore deposits in South Europe, which was exploited for Au, Ag, Pb, Zn, Fe and Cu from the Phoenician and Carthaginian times. The aim of this research work was to characterize the pedogenesis that occurred in mine tailings of different age and properties, to highlight the physical and hydrological changes that occurred as a consequence of pedogenesis, and their consequences on the environmental pollution risk. Soil profile morphology was studied in the field likewise the surficial pattern of cracks, shear strength, bulk density, and erosion. Laboratory analyses were conducted to characterize physical, chemical, elemental, mineralogical, and hydrological differences between the soil mass in the macro aggregates and in the fissures. Macroporosity was studied through image analysis of thin sections of undisturbed soil samples. X-ray diffraction (XRD) was performed on the clay fraction. Studied soils resulted strongly polluted, especially as for Zn, Pb, Cd, Cl, Mn, and Ni and were classified as different kinds of Spolic Technosol. Crack formation significantly affected shear strength, bulk density, macroporosity, saturated hydraulic conductivity, and element distribution. Gully and tunnel erosion was also driven by crack formation. The mineralogy of the clay fraction revealed that smectites are present, favouring crack opening. Crack formation deeply affected soil features and behaviour, namely hydrological properties and flow of pollutants, which in turn condition environmental health and possible soil stabilization and reclamation strategies.

Human exposure and risk assessment of cadmium for residents of abandoned metal mine areas in Korea.

The objective of this study is to find the Cd levels in agricultural crops compared to soil, to evaluate the relationship between daily intake dose through the multimedia/multi-pathway of human exposure and biomarker levels of the residents in mine vicinity area. We collected and cited the data of four out of ten health impact assessments for the residents of abandoned mine areas undertaken by the Korea Ministry of Environment in 2008. The Cd levels in soil were significantly decreased by the separation distance from the mines. The Cd levels in blood were significantly different between residents in mine areas and in comparative areas, but urinary Cd levels did not differ. The Cd levels in blood were related to the age; the separation distance from mine to residence; the daily intake dose via ingestion of drinking water, crops, and surface soil; and inhalation of ambient air of Cd, but urinary Cd levels were not relevant with various sociodemographic characteristics and exposure factors. The average hazard quotient (HQ) value of Cd in the mining site was below 1.0, but the maximum HQ was closed to 1.0. The results indicated that the ingestion of Cd-contaminated soil and agricultural crops by local inhabitants could pose potential adverse health effects to long-term residents consuming rice grown near to the mining areas.

Blood levels of cadmium and lead in residents near abandoned metal mine areas in Korea.

We analyzed national data on blood lead levels (BLL) and blood cadmium levels (BCL) in residents living near 38 abandoned metal mining areas (n = 5,682, 18-96years old) in Korea that were collected by the first Health Effect Surveillance for Residents in Abandoned Metal mines (HESRAM) from 2008 to 2011. The geometric mean BCL and BLL were 1.60μg/L (95% CI = 1.57-1.62μg/L) and 2.87μg/dL (95% CI = 2.84-2.90μg/dL), respectively, notably higher than levels in the general population in Korea and other countries. We found significantly higher BLL and BCL levels in people living within 2km of an abandoned metal mine (n = 3,165, BCL = 1.87μg/L, BLL = 2.91μg/dL) compared to people living more than 2km away (n = 2,517, BCL = 1.31μg/L, BLL = 2.82μg/dL; P < 0.0001) and to the general population values reported in the literature.

폐금속 광산의 유형별 오염특성에 관한 연구

This study is aimed to prepare the effective detail survey methods(Phase II) of abandoned metal mines through the contamination assessment for mine types and facilities in the abandoned metal mine areas. The study sites of 12 abandoned mines are located in Gyeonggi-do and Gangwon-do and those were chosen among 310 sites that the Phase II survey was conducted from 2007 to 2009 after considering the results of Phase I for abandoned mines scattered all over the country. 12 study sites were classified into four types; Type I sites only have pit mouth. Type II sites have pit mouth and mine-waste field. Type III sites have pit mouth and tailing sorting field. Type IV sites have pit mouth, tailing sorting field and concentrator(s). In forest land, paddy soil and farm land of Type I, As and Cd were showed average concentration, and Cu and Pb were high on the pit mouth area in one mines where the pit mouth was developed within 500 m. In the mines of Type II, Cu and Pb were showed average concentration too, but As and Cd were slightly high in pit mouth and mine-waste field. The mines of Type III which had grinding particle process through physical separation milling or hitting showed similar tendency with Type II. However, mines of Type IV pit mouth, mine-waste field and showed various results depending on defining the contamination sources. For example, if contamination source was pit mouth, the mixed results of Type I, II, II were showed. In tailing sorting field which was regarded as the most important source and having high mobility, however, if there were no facilities or it was difficult to access directly, field sampling was missed occasionally during phase I and phase II survey. For that reason, the assessment for tailing sorting field is missed and it leads to completely different results. In the areas of Type I mines, the concentration of heavy metals exceeded precautionary standards of soil contamination or not within 1,000 meters of pit mouth. Nickel(Ni) was the largest factor of the heavy metal contamination in this type. The heavy metals except Arsenic(As) were shown high levels of concentration in Type II areas, where pit mouth and mine-waste field were operated for making powder in upriver region; therefore, to the areas in the vicinity of midstream and downstream, the high content of heavy metals were shown. The tendency of high level of heavy metals and toxic materials contained in flotation agent used during sorting process were found in soil around sorting and tailing field. In the abandoned-pit-mouth area, drygrinding area and tailing sorting field area, the content of Cupper(Cu) and Zinc(Zn) were higher than other areas. Also, the contaminated area were larger than mine reclamation area(2,000 m) and the location of tailing sorting field was one of the important factors to estimate contaminated area.

Human Risk Assessment for Heavy Metals and as Contamination in the Abandoned Metal Mine Areas, Korea

Cleanup goals for the contaminated sites are established on the basis of risk assessments and rely on the estimated toxicity of the chemicals of concern (COC). Toxicity estimates are based on bioavailability causing risk of adverse health effects on humans. In this study, bioavailability of As, Cu, Pb and Zn in soil was determined by SBET (Simple Bioavailability Extraction Test), and chemical analysis for groundwater and stream water collected from the abandoned mine areas (Dukeum, Dongil, Dongjung, Myungbong and Songchun mine areas) was conducted. High values of cancer risk for As (1.16x10(-5)) were detected through soil ingestion pathways in the Songchun mine area and assessed through water exposure pathways in the all mines except Dukeum. The hazard index value for As in the Songchun mine area (3.625) exceeded 1.0. The results indicated that the ingestion of As-contaminated soil and water by local inhabitants can pose a potential health threat in these mine areas.

Peripheral Arterial Disease and Metals in Urine and Blood

Navas-Acien et al. (2005) recently analyzed the data from the 1999–2000 National Health and Nutrition Examination Survey (NHANES). They suggested that blood lead and blood and urinary cadmium, at levels well below safety standards, were associated with an increased prevalence of peripheral arterial disease (PAD) and that cadmium might partly mediate the detrimental arterial effects of smoking. The authors recognized that their findings needed confirmation and support from mechanistic studies. In line with their suggestion, we analyzed data from 428 participants in the Flemish Study on Environment, Genes, and Health Outcomes (Staessen et al. 1994). As described by Navas-Acien et al. (2005), we included only subjects who were at least 40 years of age and we defined PAD as an ankle brachial index of > 0.9 in at least one leg. Blood lead and blood and urinary cadmium were measured by atomic absorption spectrometry. The geometric mean concentrations were 0.43 nmol/L [5th–95th percentile interval (PI), 0.19–1.03] for blood lead and 11.6 nmol/L (PI, 3.6–31.1) for blood cadmium. The urinary cadmium excretion averaged 11.6 nmol/24 hr (PI, 3.8–35.5). We adjusted for demographic and cardiovascular risk factors. For blood lead and cadmium, the odds ratios of PAD comparing quartiles 2–4 with the lowest quartile were in line with those of Navas-Acien et al. (2005). However, for the 24-hr urinary cadmium excretion the p-value for trend was only 0.72. Urinary cadmium is a more precise biomarker of exposure than blood cadmium, because urinary cadmium reflects lifetime exposure and blood cadmium reflects more recent exposure. Navas-Acien et al. (2005) measured only metal concentrations in spot urine samples (Navas-Acien et al. 2005), whereas we measured the 24-hr excretion of cadmium. We could not demonstrate any relation between cardiovascular disease or the incidence of hypertension in relation to environmental exposure to lead and cadmium (Staessen et al. 2000). We therefore concur with their conclusion that the role of cadmium in the pathogenesis of atherosclerosis needs further research. However, not only are mechanistic studies required but also population studies, for example, that relate pulse wave velocity to biomarkers of cadmium exposure. We currently have similar experiments in progress.

Exposure assessment of heavy metals on abandoned metal mine areas by ingestion of soil, crop plant and groundwater

In order to assess the risk of adverse health effects on human exposure to arsenic and heavy metals influenced by past mining activities, environmental geochemical survey was undertaken in the abandoned metal mine areas (Dongil Au-Ag-Cu-Zn mine, Okdong Cu-Pb-Zn mine, Myungbong Au-Ag mine). Arsenic and other heavy metals were highly elevated in the tailings from the Dongil mine (8720 As mg/kg, 5.9 Cd mg/kg, 3610 Cu mg/kg, 5850 Pb mg/kg, 630 Zn mg/kg). Heavy metals except As from the Okdong mine (53.6 Cd mg/kg, 910 Cu mg/kg, 1590 Pb mg/kg, 5720 Zn mg/kg) and As from the Myungbong mine (5810 As mg/kg) were also elevated. Elevated levels of As, Cd and Zn were also found in agricultural soils from these mine areas. The H.I. (hazard index) values of As and Cd from the Dongil, the Okdong and Myungbong mine areas are higher than 1.0. Therefore, toxic risk for As and Cd exist via exposure (ingestion) of contaminated soil, groundwater and rice grain in these mine areas.