Distribution Patterns Of Metals Research Articles

DISTRIBUTION PATTERN OF HEAVY METALS IN THE SURFACE SEDIMENTS AND ENVIRONMENT QUALITY EVALUATION FOR THE YANGTZE RIVER DELTAIC ECONOMIC ZONE

This paper,based on the 1871 of geochemical data of surface sediments and other geological data,deals with the contents and distribution pattern of heavy metals in the Yangtze River Delta Economic Zone.The results show that,in the surface sediments of the study area,the average contents of As,Cd,Cr,Cu,Hg,Pb,Zn are 8.12×10-6,101.53×10-9,74.79×10-6,19.33×10-6,34.87×10-9,22.31× 10-6,and 67.13×10-6respectively.The higher values of heavy metal elements appear in the area from the Xiangshan to the Yueqing Bay,while the lower values occur along the Jiangsu coast.The comprehensive index method was adopted for environmental quality assessment.It is revealed that the heavily polluted area is located along the channel of the Yangtze River,while slightly polluted area is near the Yangtze River Estuary and the area off Ningbo and Wenzhou.The area along the Jiangsu coat is rather clean.

DISTRIBUTION PATTERN OF HEAVY METALS IN THE SURFACE SEDIMENTS OF THE AREA OF CIRCUM-BOHAI BAY AND ECOLOGICAL ENVIRONMENT ASSESSMENT

The distribution pattern of heavy metals in the surface sediments around the Circum-Bohai Bay and its influencing factors were studied in the paper.The Nemerow comprehensive index method is adopted for ecological assessment.Results show that the Liaodong Bay is the most seriously polluted area from among the three studied areas.Cd and Hg are highly beyond the standard.Spatially,high values occur in the west of the northern Liaodong Bay and the Xiaoling River estuary off the Huludao.Cu,Pb and Zn show similar distribution pattern due to similar provenance and granularity.The assessment of ecological risk indicates that the area near Huludao is the most vulnerable area in heavy metal pollution.

Distribution patterns of some heavy metals in the surface sediment fractions at northern Safaga Bay, Red Sea, Egypt

The distribution patterns, the index of geo-accumulations (MIgeo), and the enrichment ratios (ER n ) of the contaminant metals: Fe, Mn, Zn, Cu, Pb, and Ni were studied in gravel, sand, mud, coarse, medium, and fine sediment fractions of the uppermost layer of the bottom sediments collected from 12 stations covering the northern part of Safaga Bay. The distribution levels of these metals were increasing with grain size decreasing toward the central axis of the bay that extends NE–SW and southward to Safaga Harbour indicating that these metals concentrated mainly in the fine, very fine, and particulate fractions of sediments and to many anthropogenic sources. The geo-accumulation factor of Zn was more significant (MIgeo ≈ 0.62–4.23) relative to the other metals. The bay was classified as moderately to strongly polluted by Zn while it is unpolluted to moderately polluted with the other metals with accumulation sequence of: Zn>Ni>Cu>Mn≥Pb. Zn and Ni recorded the highest enrichment ratios (average ERZn ≈ 3.07 to 8.89; average ERNi ≈ 0.84 to 3.63) in the different sediment fractions relative the other metals. These enrichment ratios classified the bay as minimal enrichment, suggestive of no or minimal pollution, to significant enrichment, suggestive of a significant pollution signals with metals sequence of: Zn>Ni>Cu>Pb>Mn.

Distribution Pattern of Some Heavy Metals in the Soil of Silghat Region of Assam (India), Influenced by Jute Mill Solid Waste

Physico‐chemical Analysis of the soil of Silghat region of Nagoan district of Assam, India was carried out to assess the possible effect of jute mill solid waste in the distribution pattern of some heavy metals. Soil samples were collected from ten different locations of the dumping site of the mill and their physico‐chemical parameters were analyzed. Scanning Electron Microscopy‐Energy Dispersive X‐ray analysis (SEM‐EDX) and Inductively coupled Plasma‐Optical Emission Spectrometer (ICP‐OES) analysis of the samples shows that soil of the dumping sites is highly enriched with heavy metals. The concentration of Fe, Cu, Zn and Pb in the contaminated soil was found to be very much higher than both the continental crust and world rock average values. Correlation studies indicate strong positive correlation between organic carbon content (Corg) with all the metals investigated. pH has negative correlation while positive correlation was observed for electrical conductivity with all the metals. Extent of metal contamination was assessed by determining contamination degree (CD) and pollution load index (PLI).

Assessment of heavy metal contamination and spatial distribution in surface and subsurface sediment layers in the northern part of Lake Babrukas

It is widely accepted that heavy metal contamination in sediment, soil, and groundwater is one of the largest threats to environmental and human health. Sediments are the principle sinks for heavy metals in aquatic environments and can result in a secondary contamination source affecting the ecosystem. Analysis of heavy metal amounts in sediments and comparison with reference levels is a reliable indicator of ecosystem health, however understanding the distribution of pollutants is among most essential information for environmental research and critical for environmental management and decision-making. 64 samples were collected from surface (0–0.6 m) and subsurface (0.6–1.2 m) layers of sediments in the northern part (bay) of Lake Babrukas, which had undergone pollution by municipal wastewater in 1964–2002. The level of pollution attributed to heavy metals was evaluated using X-Ray fluorescence analysis and comparison with several reference levels (maximum allowable concentrations in soil, background concentrations in Lithuanian soils and background concentrations in Lithuanian lake sediments) in order to determine anthropogenically derived sediment contamination of bottom sediments. Spatial distribution patterns of metals in sediments were demonstrated by employing ordinary kriging interpolation. Results of heavy metal pollution analysis reveal a significant anthropogenic impact on the northern part of Lake Babrukas with concentrations of several heavy metals in both surface and subsurface layers of sediments exceeding not only background concentrations in Lithuanian soils and lake sediments, but even maximum concentrations allowable by Lithuanian legislation. Detected levels of arsenic (As), cadmium (Cd), antimony (Sb), mercury (Hg) and tin (Sn) demonstrate a significant pollution anomaly and high potential threat to the water ecosystem and even human health by exceeding maximum allowable concentration up to 10.6 times, while detected levels of chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn) show the effects of anthropogenic activity on the lake by exceeding background concentrations in Lithuanian soils and lake sediments up to 7.25 times. A comparison of heavy metal amounts and spatial distribution patterns in the two layers of sediments reveals much higher pollution levels in the subsurface (0.6–1.2 m) than surface (0–0.6 m) level by most metals, namely As, Cd, Hg, Ni, Sb and Sn, while Zn was the only metal with higher concentrations in the surface level. Spatial distribution analysis demonstrates irregular distribution of most metals due to complexity of influencing physical and chemical processes, but the general trend of high concentration anomalies stretching through the south-eastern and north-eastern parts of the bay towards its northern point is explained by former discharges of wastewater into the littoral zone of the eastern shoreline and water currents towards excess water overflow into Lake Lovka (Olauka), interconnected with Lake Babrukas in the north.

Overview of the 20th century impact of trace metal contamination in the estuaries of Todos os Santos Bay: Past, present and future scenarios

This paper discusses the distribution patterns of trace metals in sediments and suspended particulate matter (SPM) in the three main estuaries of the Todos os Santos Bay (BTS), Brazil, during dry and rainy seasons. Data available up to 2012 was also reviewed to assess the status of contamination. For most elements, metal concentrations in sediments decreased from the tidal limits to the lower estuary. Metals in SPM presented more complex distributions along the salinity gradient. Metal variability between rainy and dry conditions was only significant for SPM data. Of the BTS estuaries, the levels of Cd, Zn, Pb and Cu are highest in the Subaé estuary, and they seem to be promoting harmful biological effects in macrofauna, and also may pose potential human health risks. Despite the evidence of important localized contamination, much of the data compiled indicates that the bay and its estuaries are still relatively preserved.

Heavy metals accumulation and distribution pattern in different vegetable crops

Different vegetable crops grown on heavy metal contaminated soil showed marked difference in metal accumulation, their uptake and distribution pattern. Crop species also showed remarkable difference in metal concentration of various plant parts. Based on metal accumulation in edible parts and whole plants, root vegetables namely, radish and carrot registered lower accumulation of almost all heavy metals except Zn in radish root. However, leafy vegetables namely, spinach, amaranthus, mustard and fenugreek recorded higher accumulation of both essential and non-essential heavy metals, except Cd and Ni which showed less accumulation in fenugreek. Potato and onion showed lower accumulation of Zn and Cu and higher accumulation of Cd and Ni. Cauliflower and cabbage, however, showed greater accumulation of Pb and Ni, but less accumulation of Cu and Cd. Among fruit type vegetables, pea, soybean and cluster bean showed greater accumulation of Pb and Ni and very less accumulation of Cd. Among different vegetables cauliflower and cabbage recorded highest uptake of Zn, Pb and Ni, while mustard showed higher uptake of Zn and Cd. In general the uptake of Cd was lowest in almost all the crops except mustard. Generally the root and leafy vegetables namely. radish, carrot, spinach, amaranthus, mustard, cauliflower and cabbage showed higher distribution of metals to the edible parts, whereas fruit types vegetables specially tomato and brinjal exhibited least transport of metals to fruits except leguminous fruit vegetables pea and soybean. Leafy vegetables namely, spinach, amaranthus and mustard seemed to be unsafe and not suitable for cultivation on heavy metal contaminated soil. Most of the fruit type vegetables could be suggested for cultivation on Cd contained soil but not for Ni and Pb contained soil. Key words: Heavy metals, accumulation, distribution, uptake.

Spatial Distribution and Contamination Assessments of Heavy Metals in Sediments of Wenruitang River, Wenzhou, China

Sediments from 29 stations within Wenruitang River basin were sampled to investigate the spatial distribution patterns of heavy metals in sediments and to assess the pollution status of heavy metal elements (Cd, Cr, Cu, Ni, Zn and Pb). Heavy metal concentrations showed significant spatial variation in sediments from different areas. Enrichment factors (EF) indicated that the order of pollution level was as follows: Cd＞Cu＞Zn＞Ni＞Cr＞Pb. The major heavy metal contaminants were derived from human impacts. Correlation analysis suggested that Cu, Zn, Ni, Cd and Pb were significantly related to total organic carbon (TOC); Cu, Ni, Pb, Zn and Cr had a close association with each other; Cd was closely associated with Zn.

Influence of Traffic Activity on Heavy Metal Concentrations of Roadside Farmland Soil in Mountainous Areas

Emission of heavy metals from traffic activities is an important pollution source to roadside farmland ecosystems. However, little previous research has been conducted to investigate heavy metal concentrations of roadside farmland soil in mountainous areas. Owing to more complex roadside environments and more intense driving conditions on mountainous highways, heavy metal accumulation and distribution patterns in farmland soil due to traffic activity could be different from those on plain highways. In this study, design factors including altitude, roadside distance, terrain, and tree protection were considered to analyze their influences on Cu, Zn, Cd, and Pb concentrations in farmland soils along a mountain highway around Kathmandu, Nepal. On average, the concentrations of Cu, Zn, Cd, and Pb at the sampling sites are lower than the tolerable levels. Correspondingly, pollution index analysis does not show serious roadside pollution owing to traffic emissions either. However, some maximum Zn, Cd, and Pb concentrations are close to or higher than the tolerable level, indicating that although average accumulations of heavy metals pose no hazard in the region, some spots with peak concentrations may be severely polluted. The correlation analysis indicates that either Cu or Cd content is found to be significantly correlated with Zn and Pb content while there is no significant correlation between Cu and Cd. The pattern can be reasonably explained by the vehicular heavy metal emission mechanisms, which proves the heavy metals’ homology of the traffic pollution source. Furthermore, the independent factors show complex interaction effects on heavy metal concentrations in the mountainous roadside soil, which indicate quite a different distribution pattern from previous studies focusing on urban roadside environments. It is found that the Pb concentration in the downgrade roadside soil is significantly lower than that in the upgrade soil while the Zn concentration in the downgrade roadside soil is marginally higher than in the upgrade soil; and the concentrations of Cu and Pb in the roadside soils with tree protection are significantly lower than those without tree protection. However, the attenuation pattern of heavy metal concentrations as a function of roadside distance within a 100 m range cannot be identified consistently.

Trace metal concentrations in the tropical sponge Spheciospongia vagabunda at a sewage outfall: synchrotron X-ray imaging reveals the micron-scale distribution of accumulated metals

Major and trace elements were measured in sponges, seawater and sediment in Darwin Harbour (Australia) to test the hypothesis that metals are elevated in sponges closer to a sewage outfall compared with unimpacted sites. Seawater and sediment at the sewage discharge site contained high, but localised, concentrations of phosphorus (P), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As) and lead (Pb) compared with background sites. Metal concentrations in the sponge Spheciospongia vagabunda were highly elevated compared with other sponges and, although site specific, high metal concentrations were unrelated to the presence of sewage effluent. X-ray fluorescence microprobe imaging was used to investigate the metal distribution pattern in S. vagabunda. High Fe, Ni and Zn concentrations were either localised in circular patches (100–200 μm size) near water canals or in the pinacoderm, or scattered in spots (approximately 10 μm) throughout the tissue. This supports a microflora-mediated metal bioaccumulation hypothesis. In contrast, Co and Mn were highly dispersed and probably associated with aluminium- and iron-oxide rich sediment inclusions. Although the lack of association between sewage effluent and metal accumulation precludes the use of S. vagabunda as a biomonitor, the apparent differential mechanisms of metal accumulation warrants further investigation.

Multivariate analysis of mixed contaminants (PAHs and heavy metals) at manufactured gas plant site soils

Principal component analysis (PCA) was used to provide an overview of the distribution pattern of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in former manufactured gas plant (MGP) site soils. PCA is the powerful multivariate method to identify the patterns in data and expressing their similarities and differences. Ten PAHs (naphthalene, acenapthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo[a]pyrene) and four toxic heavy metals - lead (Pb), cadmium (Cd), chromium (Cr) and zinc (Zn) - were detected in the site soils. PAH contamination was contributed equally by both low and high molecular weight PAHs. PCA was performed using the varimax rotation method in SPSS, 17.0. Two principal components accounting for 91.7% of the total variance was retained using scree test. Principle component 1 (PC1) substantially explained the dominance of PAH contamination in the MGP site soils. All PAHs, except anthracene, were positively correlated in PC1. There was a common thread in high molecular weight PAHs loadings, where the loadings were inversely proportional to the hydrophobicity and molecular weight of individual PAHs. Anthracene, which was less correlated with other individual PAHs, deviated well from the origin which can be ascribed to its lower toxicity and different origin than its isomer phenanthrene. Among the four major heavy metals studied in MGP sites, Pb, Cd and Cr were negatively correlated in PC1 but showed strong positive correlation in principle component 2 (PC2). Although metals may not have originated directly from gaswork processes, the correlation between PAHs and metals suggests that the materials used in these sites may have contributed to high concentrations of Pb, Cd, Cr and Zn. Thus, multivariate analysis helped to identify the sources of PAHs, heavy metals and their association in MGP site, and thereby better characterise the site risk, which would not be possible if one uses chemical analysis alone.

Speciation of heavy metals by modified BCR sequential extraction procedure in different depths of sediments from Sungai Buloh, Selangor, Malaysia

The sequential extraction procedure proposed by the European Standard, Measurements and Testing (SM&T) program, formerly the Community Bureau of Reference (BCR), was applied for partitioning of heavy metals (HMs) in river sediments collected along the course of Sungai Buloh and the Straits of Malacca in Selangor, Malaysia. Eight elements (V, Pb, Cd, Cr, Co, Ni, Cu and Zn) from seven stations (S1–S7) and at different depths were analyzed using the modified BCR Sequential Extraction Procedure (SEP) in combination with ICP-MS to obtain the metal distribution patterns in this region. The results showed that heavy metal contaminations at S2 and S3 was more severe than at other sampling sites, especially for Zn, Cu, Ni and Pb. Nevertheless, the element concentrations from top to bottom layers decreased predominantly. The samples from the Straits of Malacca (S4–S7) the highest contamination factors obtained were for Co, Zn and Pb while the lowest were found for V and Cr, similar to Sungai Buloh sediments. The sediments showed a low risk for V, Cr, Cu and Pb with RAC values of less than 10%, but medium risk for Co, Zn (except S3), Cd at S1 and S2 and Ni at S1, S3 and S5. Zn at S3 and Cd at S3–S7 showed high risk to our sediment samples. There is not any element of very high risk conditions in the selected samples.

Assessment of Polycyclic Aromatic Hydrocarbons (PAH) and Heavy Metals in the Vicinity of an Oil Refinery in India

Petroleum products are one of the major sources of energy for industry and daily life. Growth of the petroleum industry and shipping of petroleum products has resulted in the pollution. Populations living in the vicinity of oil refinery waste sites may be at greater risk of potential exposure to polycyclic aromatic hydrocarbons (PAH) through inhalation, ingestion, and direct contact with contaminated media. PAH have often been found to coexist with environmental pollutants including heavy metals due to similar pollution sources. The levels and distribution patterns of Σ16 PAH (sum of the 16 PAH) and heavy metals (lead, copper, nickel, cobalt, and chromium) were determined in soil and sediment in the vicinity (5 km radius) of an oil refinery in India. Concentrations of Σ16 PAH in the soils and sediments were found to be 60.36 and 241.23 ppm, respectively. Higher amount of PAH in sediments as compared to soil is due to low water solubility of PAH, settled in the bottom of aquatic bodies. The levels of lead, copper, nickel, cobalt, and chromium (total) in soil were 12.52, 13.52, 18.78, 4.84, and 8.29 ppm, while the concentrations of these metals in sediments were 16.38, 47.88, 50.15, 7.07, and 13.25 ppm, respectively. Molecular diagnostics indices of PAH (Ratio of Phenanthrene/Anthracene, Fluranthene/Pyrene) calculated for soil and sediment samples indicate that the oil refinery environment is contaminated with PAH from petrogenic as well as pyrolytic origin and heavy vehicular traffic on the Agra- Delhi National highway. Sixteen PAH priority pollutants were detected in the United States in entire samples collected near oil refinery areas and concentrations of Σ16 PAH in soil was found to be 1.20 times higher than the threshold value for PAH in soil by ICRCL (Inter-Departmental Committee on the Redevelopment of Contaminated Land). This concentration could lead to disastrous consequences for the biotic and abiotic components of the ecosystem and may affect the soil quality, thus impairing plant growth and its bioaccumulation in food chain.

Lime Treatment of Mine Drainage at the Sarcheshmeh Porphyry Copper Mine, Iran

Laboratory and field treatment tests were performed to evaluate the effectiveness of lime treatment for mitigation of environmental effects of acid mine drainage (AMD) at the Sarcheshmeh porphyry copper mine. AMD associated with the rock waste dumps is contaminated with Al (>36,215 μg/L), Cd (>105 μg/L), Co (>522 μg/L), Cu (>53,250 μg/L), Mn (>42,365 μg/L), Ni (>629 μg/L), and Zn (>12,470 μg/L). The concentrations of other metals (Fe, Mo, Pb, and Se) are low or below detection limits (As, Cr, and Sb). Due to the very high Al and Mn content and the low concentration of Fe, a two-stage lime treatment method was chosen for the laboratory tests. In the first stage, the AMD was treated at four pH set points: 7.5, 8.9, 9, and 10. In the second stage, after removing the sludge at pH 9, treatment was continued at pH 10 and 11. The results indicated that a two-stage treatment method was not necessary because elements such as Al, Cu, Co, and Zn were easily treated at pH 7.5, while complete removal of Cd, Mn, and Ni only required a pH of 10. Increasing pH during the treatment process only caused a slight increase in Al. Field treatment tests support the laboratory results. Lime treatment of highly contaminated AMD from dump 11, using simple low density sludge pilot scale equipment, show that contaminant metals are treatable using this method. The mean treatment efficiency for contaminant metals was 99.4% for Al, % for Cd, 99.6% for Co, 99.7% for Cu, 98.5% for Mn, 99.7% for Ni, 99% for U, and 99.5% for Zn. The optimum pH for AMD treatment by lime was in the range of 9–10. The produced sludge in the treatment process was highly enriched in the contaminant metals, especially Cu (>7.34%), Al (>4.76%), Mn (>2.94%), and Zn (>1.25%). A correlation coefficient matrix indicates that the distribution pattern of the contaminant metals between soluble and precipitated phases is consistent with the hydrochemical behavior of the metals during the lime treatment process.

Bioaccumulation of trace metals in the submarine hydrothermal vent crab Xenograpsus testudinatus off Kueishan Island, Taiwan

The concentrations of ten trace metals were determined in the gills, muscles, hepatopancreas, and exoskeleton tissues of Xenograpsus testudinatus that lives around shallow and acidic hydrothermal vents off Kueishan Island, northeastern Taiwan. The analytical results demonstrate that the metal concentrations vary significantly with the type of crab tissue. The concentrations of Al, Cd, Co, Cu, Fe, Ni, and Zn are highest in the gills, whereas the concentration of Mn is highest in the exoskeleton. Cr and Pb concentrations are similar across the different tissues. The enhanced accumulation of most metals in the gills suggests the metal accumulation via the respiration pathway rather than the uptake of food. The results also reveal that the distribution patterns of metals in tissues are similar in the hepatopancreas and muscles, but very different in both the gills and the exoskeleton, perhaps because of the different pathways of metal utilization in the different crab tissues.

The preferential accumulation of cadmium in the head portion of the freshwater planarian, Dugesia japonica (Platyhelminthes: Turbellaria)

Free-living freshwater planarians are considered to have the potential for development as an experimental model for toxicological studies on xenobiotics, including metals. However, little was known about the distribution patterns of metals in the body of treated planarians. This study was conducted to determine the tissue distribution patterns of cadmium (Cd) in different body portions of the treated planarian, Dugesia japonica. Results showed that Cd accumulated in the head of planarians at a significantly higher concentration than in the tail. After examining the level of metallothionein (MT), we suggested that the tissue distribution pattern of Cd might be related to MT induction patterns. In contrast, in planarians treated with copper (Cu), neither the tissue accumulation of Cu nor the multiples of induction of MTs significantly differed between different portions. Furthermore, a higher Cd accumulation rate in the head of planarians caused more-severe oxidative stress to appear in this portion and also a higher susceptibility to a lethal concentration of Cd. Finally, both in vitro and in vivo acetylcholinesterase activities in both body portions of planarians were inhibited by Cd. The present study provides the first report that different metals are distributed in various body portions with different patterns in the planarian.

Distribution of potentially toxic metal and radionuclide contamination in soils related to phosphogypsum waste stockpiling in the Eshidiya Mine, Jordan

ABSTRACT Prior to this study, phosphogypsum (PG) stockpiles at the Eshidiya mine in Jordan were thought to be potentially enriched with potentially toxic metals and radionuclides, resulting in possible environmental degradation of the surrounding ecosystem. In order to investigate this phenomenon, enrichment levels and distribution patterns of metals (e.g. Zn, Cd, V) and radionuclides in the underlying soils, alluvium, and yellow marl bedrock were determined and compared against those in the PG stockpiles. The 226 Ra, 210 Pb, and 238 U in soil reached peak concentrations of 1.5 pCi/g, 2.0 pCi/g, and 1.1 pCi/g, respectively. These elemental concentrations are similar to their concetrations in the uncontaminated soils, whereas the concentrations of these elements exhibit higher concentrations in PG and are as follows: 226 Ra= 18 pCi/g, 210 Pb= 19 pCi/g, and 238 U= 4 pCi/g . The elements Cd, Zn, and V have maximum concentrations of 3 mg kg −1 , 69 mg kg −1 and 62 mg kg −1 , respectively, in the soil9s layer. These elemental concentrations are relatively lower than in uncontaminated soil and the PG. The degrees of mobility of the determined elements in soils were classified into three categories: elements with high mobility are Se, Mn, Pb, and Cr; those with moderate mobility are Co, Ni, As, Hg, Cu, V, and Zn; and those with low mobility are U, Cd, 210 Pb, 226 Ra, and 238 U. Following correlation analysis, R-mode factor analysis was applied in conjunction with mineralogy to understand the geochemical variability of the soil. Four main meaningful factors were extracted: a detrital quartz factor, a clay minerals factor, a carbonate factor, and a terrigenous minerals factor. To investigate the spatial distribution patterns of the elements, a contour mapping technique was applied, allowing the following conclusions: (1) The elements 210 Pb, 226 Ra, and U exhibit similar distribution patterns; (2) Cd and Cu show similar distribution patterns; (3) As and V exhibit similar distribution patterns; and (4) no observed trend was observed for Cr. Generally, the results revealed that potentially toxic metals and radionuclides are not contaminated in soils related to the phosphogypsum stockpiles, and the soils of the Eshidiya area do not contain potentially toxic metals and radionuclide concentrations that threaten the surrounding ecosystem.

Trace metal contents in barbeque (BBQ) charcoal products

In this study, the concentrations of trace elements contained in solid barbeque (BBQ) charcoal products have been investigated. Eleven brands of charcoal products were analyzed, consisting of both Korean (3 types) and imported products (eight types from three countries) commonly available in the Korean market places. The concentrations of trace metals in solid charcoal varied widely across metal types and between samples with the overall range of 5 μg kg −1 (As) to 118 mg kg −1 (Zn). The patterns of metal distribution between different products appeared to be affected by the properties of raw materials and/or the processes involved in their production. Although concentrations of certain trace metals were significantly high in certain charcoal samples, their emission concentrations were below legislative guidelines (e.g., the permissible exposure limit (PEL) set by the Occupational Safety and Health Administration (OSHA)). In light of the potential harm of grilling activities, proper regulation should be considered to control the use of BBQ charcoal from a toxicological viewpoint to help reduce the potential health risks associated with its use.

Evaluation of Metal Concentrations in Red Tilapia (Oreochromis spp) from Three Sampling Sites in Jelebu, Malaysia Using Principal Component Analysis

Concentration of V, Mn, Fe, Co, Cu, Zn, As, Se, Cd, and Pb in muscle, liver, and gill tissues of red tilapia (Oreochromis spp) sampled from three different aquaculture sites which include earthen pond, ex-tin mining pool, and concrete tank in Jelebu, Negeri Sembilan, were determined using microwave-assisted digestion–inductively coupled plasma-mass spectrometry. Accumulation patterns relating organs and elements, as well as origins and elements, were evaluated using multivariate statistics. With the aid of principal component analysis, it is possible to visualize the distribution pattern of metals in different organs as well as clustering tendencies of tilapia samples according to the production sites. In general, levels of V, Co, Fe, Cu, Zn, Se, and Cd in liver were higher than those in muscles and gills, whereas Mn and Pb were higher in gills while As in muscles. Results from principal component analysis revealed that there are similar pattern of metal distribution among organs regardless of the production sites. It is also suggested that Cu, As, and Pb are the best describers in characterizing the studied organs, where liver tissues are associated with high Cu, gills with high Pb, and muscles with high As. On the other hand, V, Co, and Pb are observed to be key discriminants for sample origins.

Chemometric interpretation of heavy metal patterns in soils worldwide

Principal component analysis (PCA) was applied on data sets containing levels of six heavy metals (Pb, Cu, Zn, Cd, Ni, Cr) in soils from different parts of the world in order to investigate the information captured in the global heavy metal patterns. Data used in this study consisted of the heavy metal contents determined in 23 soil samples from and around the Novi Sad city area in the Vojvodina Province, northern part of Serbia, together with those from the city of Banja Luka, the second largest city in Bosnia and Herzegovina, and the ones reported previously in the relevant literature in order to evaluate heavy metal distribution pattern in soils of different land-use types, as well as spatial and temporal differences in the patterns. The chemometric analysis was applied on the following input data sets: the overall set with all data gathered in this study containing 264 samples, and two sub sets obtained after dividing the overall set in accordance to the soil metal index, SMI, calculated here, i.e. the set of unpolluted soils having SMIs < 100%, and the set of polluted soils with SMIs > 100%. Additionally, univariate descriptive statistics and the Spearman’s non-parametric rank correlation coefficients were calculated for these three sets. A Box–Cox transformation was used as a data pretreatment before the statistical methods applied. According to the results, it was seen that anthropogenic and background sources had different impact on the data variability in the case of polluted and unpolluted soils. The sample discrimination regarding the land-use types was more evident for the unpolluted soils than for the polluted ones. Using linear discriminant analysis, content of Cu was determined as a variable with a major discriminant capacity. The correct classification of 73.3% was achieved for predefined land-use types. Classification of the samples in accordance to the pollution level expressed as SMI was necessary in order to avoid the “masking” effect of the polluted soil patterns over the non-polluted ones.