Impact of Landfill Sites on Coastal Contamination Using GIS and Multivariate Analysis: A Case from Al-Qunfudhah in Western Saudi Arabia

The objective of this paper was to stress the possible potential toxic element (PTE) accumulation in the surface sediments of the Çavuşlu Stream (ÇS), as well as examining the source identification of whether or not any association between garbage disposal facility (GDF) and ecotoxicity or human health risk in Giresun, Turkey. The sediment specimens were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS) followed by microwave digestion. The descending order of metals (mg/kg) in sediments were as follows: Fe (38,791 ± 3269) > Al (27,753 ± 4051) > Mn (730.90 ± 114.60) > Cr (233.39 ± 53.32) > V (176.40 ± 19.66) > Cu (85.22 ± 6.06) > Ni (72.87 ± 11.50) > Zn (46.45 ± 3.68) > Co (21.96 ± 3.33) > Pb (12.17 ± 1.97) > As (3.12 ± 1.45) > Sb (0.22 ± 0.06) > Cd (0.17 ± 0.02) > Hg (0.04 ± 0.01). Among these elements, certain metals (V, Cr, Cu, and Ni) in the sediments were above the average shale. Cr and Ni levels were above their corresponding threshold effect level (TEL) and probable effect level (PEL) values while Cu concentration exceeding its TEL, indicating that benthic organisms in the sediment of ÇS have likely toxic responses. Based on the results from contamination factor (CF), enrichment factor (EF), and geo-accumulation factor (Igeo) values of PTEs, the sediment was frequently classified into moderate contamination, moderate enrichment, and unpolluted to moderately polluted group. Pollution load index (PLI), integrated pollution index (IPI), and ecological risk index (Eri) indicated low pollution or low potential ecological risk. Toxicity risk index (TRI) and toxic unit analysis (TUs) suggested moderate toxicity. The outcomes of hazard quotient (HQ), total hazard index (THI), and lifetime cancer risk (LCR) stressed out that PTEs would not pose a significant health risk when adults are exposed to sediments in ÇS. However, a non-cancerogenic health risk for children was considered as the collective effect of 14 PTE (THI = 1.47 > 1). Multivariate statistical analysis (principal component analysis (PCA), Pearson's correlation coefficient (PCC), and hierarchical cluster analysis (HCA)) outlined that the metallic accumulation in the sediments of ÇS was related to lithological, geological, and anthropogenic impacts. Therefore, the GDF is likely a major reason in terms of anthropogenic pollution in the sediments of the ÇS.

East Kolkata Wetland (EKW) is one of the largest sewage-fed wetlands in the world, which support the livelihood of thousands of peoples. However, at present, EKW system has become ecologically vulnerable due to the discharge of toxic waste through the sewage canal from the Kolkata metropolitan city. Hence, it becomes very important to understand the inflow and load of potentially toxic elements (PTE) in the sediment, water, and fish of sewage-fed wetland used for aquaculture activities. In this study, one of the polluted wetland from EKW, Sardar bherry, was selected as the study area. Sediment samples (45) were collected from 15 sites to characterize the PTEs concentrations levels utilizing inductively coupled plasma mass spectrometry, and their spatial distribution pattern and pollution quality indices were estimated. Water (45) and fish (7) samples were also analyzed to understand the distribution pattern of PTEs from sediment to water and water to fish. The geostatistical prediction map showed that the concentration range of Cr, Fe, Cu, Co, Zn, Cd, Ni, Pb, and Mn in sampling stations were 27.3-84.1 μg g-1, 7281-30193 μg g-1, 50.6-229.7 μg g-1, 4.8-15.3 μg g-1, 113.4-776.9 μg g-1, 10.0-26.9 μg g-1, 23.8-55.7 μg g-1, 9.5-39.3 μg g-1, and 188.6-448.5 μg g-1 respectively. Pollution is alarming in sediment as all of the studied PTEs exceed the threshold effect level according to Sediment Quality Guidelines. Cd levels in sediments were found to be upper than the lowest effect level (LEL), probable effect level (PEL), threshold effect level (TEL), and severe effect level (SEL) for all sample locations. Several pollution assessment indexes (contamination factor, geo-accumulation index, ecological risk index, etc.) also showed that sediment samples were severely polluted by Cd. PTEs status in water and fish is within permissible limits. The study emphasizes that attention should be paid to controlling the excessive accumulation of PTEs in sediment that would further harm the ecological environment and ultimately human health.

Human health risk assessment from potentially toxic elements in the soils of Sudan: A meta-analysis.

The Beijing–Tianjin–Hebei region is mostly located in the Haihe Basin. Studying the distribution and sources of potentially toxic elements (PTEs) and heavy metals in the upper reaches of Zhanghe River, the largest tributary of Haihe runoff, is of great significance to the water security of Beijing–Tianjin–Hebei region, a world-class urban agglomeration. In this study, 32 sediment samples were collected in the upper reaches of Zhanghe River, and the concentrations of eight PTEs were analyzed. The results show that the concentrations of PTEs in sediments ranked are as follows: Mn > Cr > Zn > Cu > Pb > Co > As > Cd. Cr, Cu, Zn, and Cd show a random spatial variation trend; Mn, As, and Pb are mainly distributed in the headwaters of the Zhuozhang River. Ninety percent of samples of Cr, Cu, Zn, Cd, and Pb are under the threshold effect level, and 16% of the Cr samples are above the probable effect level. PTEs in the study area have low to moderate pollution as the enrichment factor and geo-accumulation index showed, and the contribution of anthropogenic sources to the enhancement of PTEs in sediment samples is still at a preliminary stage. Potential ecological risk results indicate that 96% of the upper reaches of Zhanghe River have a low risk level. The three evaluation methods all point out that Cr is the main pollutant in the upper reaches of Zhanghe River, and the Southern Headwater of Zhuozhang River is the main polluted area. Cr, Mn, Co, and Pb originate from mining activities and road dust, while Cu, Zn, As, and Cd originate from agricultural activities.

Groundwater quality assessment in western Saudi Arabia using GIS and multivariate analysis

Street dust samples were collected from 31 sampling sites which were classified into four different groups in Zawiya, Libya, covering different traffic, city center, junkyards, oil refinery, farming, and household activities. Since the potentially toxic elements (PTEs) in street dust have a non-negligible impact on health, the aim of this study is to investigate the sources, pollution level and human health risk of PTEs. In this study, wavelength distribution X-ray fluorescence device was used to determine the concentration of PTEs. The spatial distribution, contamination levels, sources, and human health risks of PTEs in road dust were evaluated. The PTEs content of the street dust were found as Cr>Mn>Zn>Pb>Cu>Ni>Co. The average concentration of most PTEs (Co, Cu, Mn, Ni and Zn) was higher in junkyards and heavily traffic areas than in other areas. Cobalt and Cu has the highest geo accumulation index (Igeo) values, and due to these values, the study area was evaluated as moderately to heavily contaminated. Enrichment factor (EF) values of Cr, Pb and Zn exhibited a significant enrichment, indicating that some sampling sites were affected by anthropogenic sources. There was no lifetime cancer risk for exposure to PTEs in street dust by inhalation in Zawiya. Each hazard quotient (HQ) and hazard index (HI) for all PTEs were less than 1, indicating that exposure to PTEs in street dust did not have significant non-carcinogenic risks for both adults and children. In conclusion, Zn, Pb, Cu, Mn, and Cr were represented by the largest portion of the total data variance in the principal component analysis (PCA), and they were positively correlated. It was seen that study area was influenced by anthropogenic sources rather than natural sources, but there was no health risk.

This paper revealed that the level of certain potentially toxic elements (PTEs) can be reflected in stream and terrace sediments from Harsit Stream in Northeast Turkey. The potential toxicity of these elements was established by determining and interpreting the enrichment factor (EF), contamination index (Pi), ecological risk index ( $$ {E}_{\mathrm{r}}^i $$ ), modified hazard quotient (mHQ), hazard quotient (HQ), and hazard index (HI). The distribution of PTEs in the sediment samples was non-uniform along the different sites of the stream. The change in concentration was attributed to the release of these elements from different sources (agricultural activities, industrial activities, and gasoline discharges). Results indicated that the stream sediments were locally contaminated by the following PTEs: Pb, As, and Cd based on EF values; Cu, Pb, Zn, As, Cd, and Hg based on Pi; Pb, Cd, and Hg based on $$ {E}_{\mathrm{r}}^i $$ ; and Pb, As, Cd, and Hg based on mHQ. According to the HQ and HI values of Pb, risks were posed to human health especially to children. Meanwhile, terrace sediments were locally contaminated as follows: Zn and As based on EF; Cu, Pb, Zn, As, and Cd based on Pi; and Zn and Cd based on $$ {E}_{\mathrm{r}}^i $$ . The HQ and HI values of As were found to be > 1, suggesting a high chance of health risk to children. The PTE levels and the local distribution pattern revealed that agricultural activities, industrial functions, and gas stations along the stream were probable sources of toxic element contamination in sediments from the Harsit Stream. These findings can help evaluate the potential toxicity risks affecting living organisms.

The concentrations of potentially toxic elements (PTEs) and their contamination indices were determined in urban soil from five different land-use zones, namely municipal solid waste landfill (MWL), industrial area (INA), heavy traffic area (TRA), residential area with commercial activities (RCA), and farmland (FAL) in Osogbo Metropolis. Ecological and human health risk assessments were also evaluated. Based on the average concentrations, the highest values of As, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn were found at INA, while the maximum concentrations of Ba, Cd, and Co were observed at MWL. The average enrichment factor (EF) values of Cd, Cu, Pb, and Zn showed very high to extremely high enrichment in the soils of INA, MWL, TRA, and RCA, while the EF values of Ba, Co, Cr, Fe, Ni, and V were significantly to moderately enriched in the aforementioned land-use zones. This trend was consistent with the average contamination factor (Cf) values of Cd, Cu, Pb, and Zn, which indicated considerable to very high contamination at INA, MWL, TRA, and RCA. However, Cf values of Ba, Co, Cr, Fe, Ni, and V had moderate contamination variously at the different land-use zones. Furthermore, the potential ecological risk factor (Eri) values for all the PTEs were < 40, which indicated low Eri, except for Cd and to some extent Pb. The Eri value of Cd was high to very high at MWL, INA, TRA, and RCA, and low at FAL, while Eri of Pb was only moderate at INA. Assessment of health quotient (HQ) of non-carcinogenic health risks was within acceptable limit (< 1) for most of the PTEs in the different zones for adults and children, except the maximum HQ value of Pb at INA (HQ = 1.0), which was beyond the acceptable limit for children. The carcinogenic risk was within the acceptable limit (1.0 × 10-6) in all the zones, except INA. This may pose health challenges to children in the vicinity of the pollution sources. Continuous monitoring of PTEs to reduce exposure to PTE should be considered.

Potentially toxic elements in soil and road dust around Sonbhadra industrial region, Uttar Pradesh, India: Source apportionment and health risk assessment

Impact of MSW landfill on the environmental contamination of phthalate esters

Fine road dust is a major source of potentially toxic elements (PTEs) pollution in urban environments, which adversely affects the atmospheric environment and public health. Two different sizes (10–63 and <10 μm) were separated from road dust collected from Apia City, Samoa, and 10 PTEs were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Fine road dust (<10 μm) had 1.2–2.3 times higher levels of copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), antimony (Sb), lead (Pb), and mercury (Hg) than 10–63 μm particles. The enrichment factor (EF) value of Sb was the highest among PTEs, and reflected significant contamination. Cu, Zn, and Pb in road dust were also present at moderate to significant levels. Chromium (Cr), cobalt (Co), and nickel (Ni) in road dust were mainly of natural origins, while Cu, Zn, Sb, and Pb were due to traffic activity. The levels of PTEs in road dust in Samoa are lower than in highly urbanized cities, and the exposure of residents in Samoa to PTEs in road dust does not pose a noncarcinogenic health risk. Further studies of the effects of PTEs contamination in road dust on the atmosphere and living organisms are needed.

Potentially toxic elements (PTEs) are a major source of pollution due to their toxicity, persistence, and bio-accumulating nature in riverine bed sediments. The sediment, as the largest storage and source of PTEs, plays an important role in transformation of mercury (Hg), lead (Pb), nickel (Ni), chromium (Cr), copper (Cu), zinc (Zn), and other toxic PTEs. Several important industrial hubs that contain a large population along the banks of different rivers, such as Kabul, Sutlej, Ravi, Jhelum, and Chenab in Pakistan, are acting as major sources of PTEs. In this study, 150 bed sediment samples (n=30 from each river) were collected from different sites. Total (acid extracted) PTE (Hg, Cu, Cr, Ni, Zn, and Pb) concentrations in bed sediments were determined using inductively coupled plasma mass spectrometry (ICP-MS). Sediment pollution indices were calculated in the major rivers of Pakistan. The results demonstrated high levels of Hg and Ni concentrations which exceeded the guideline standards of river authorities in the world. The contamination factor (CF) and contamination degree (CD) indices for Hg, Ni, and Pb showed a moderate to high (CF≥6 and CD≥24) contamination level in all the selected rivers. The values of geo-accumulation index (Igeo) were also high (Igeo≥5) for Hg and Pb and heavily polluted for Ni, while Cr, Cu, and Zn showed low to unpolluted (Igeo) values. Similarly, the enrichment factor (EF) values were moderately severe (5≤EF≤10) for Hg, Pb, and Ni in Sutlej, Ravi, and Jhelum, and severe (10≤EF≤25) in Kabul and Jhelum. Moreover, Hg and Ni showed severe to very severe enrichment in all the sampling sites. The ecological risk index (ERI) values represented considerable, moderate, and low risks, respectively, for Hg (The ERI value should not be bold. Please unbold the ERI in the whole paper. It should be same like RI, CD and EF.[Formula: see text]≥160), Pb and Ni (40≤[Formula: see text]≤80), and Cr, Cu, and Zn ([Formula: see text]≤40). Similarly, potential ecological risk index (PERI) values posed considerable (300≤RI≤600) risk in Ravi and moderate (150≤RI≤300) in Kabul and Jhelum, but low (RI≤150) risk in Ravi and Chenab. On the basis of the abovementioned results, it is concluded that bed sediment pollution can be dangerous for both ecological resources and human beings. Therefore, PTE contamination should be regularly monitored and a cost-effective and environmentally friendly wastewater treatment plant should be installed to ensure removal of PTEs before the discharge of effluents into the freshwater ecosystems.

In the Philippines, legacy mines and active mine wastes pose potential threats since these may contain elevated concentrations of potentially toxic elements (PTEs) and high natural radioactivity. In this study, legacy mine wastes from the Philippine Iron Mine (PIM), Barlo Mine (BM), and Rapu-Rapu Mine (RRM) and active mine tailing from Padcal Mine (PM) were analyzed to determine the concentrations of fifteen (15) PTEs and the activity concentrations of natural radionuclides. Several quantitative risk indicators and radiological health risk parameters were utilized to determine the potential effects of these mine wastes to the natural environment and to human health. Legacy mine wastes have higher contents of PTEs and are more polluted by PTEs than PM tailing. Both enrichment factor (EF) and geoaccumulation index (I&lt;sub&gt;geo&lt;/sub&gt;) values suggest that legacy mine wastes are strongly polluted by As, Cd, Cu, and Mo. BM and RM wastes are also polluted by Pb, Sb, and Zn; PIM waste is polluted by Ni and V; and BM waste is polluted by Tl. Padcal mine tailing is only moderately polluted by Cu and Mo. The natural radionuclide activity concentrations of legacy and active mine wastes are below the global background values and the radiological hazard indices are also all lower than their permissible limits, except for &lt;sup&gt;40&lt;/sup&gt;K, &lt;sup&gt;238&lt;/sup&gt;U, and absorbed gamma dose rate in PIM due to a geogenic source. Unlike the PTEs, radioactivity in the legacy and active mine wastes are not enhanced by mining activities and is not a significant risk factor to human health.

The Al-Uqair coast, situated along the western shore of the Arabian Gulf, has undergone rapid development in recent years driven by expanding oil-industrial activities, modern agricultural settlements, and tourism. Such activities raise concerns regarding the potential contamination of the coastal environment with potentially toxic elements (PTEs), which may pose ecological and human health risks. In this study, the concentrations of Cu, Ni, Pb, Cr, As, and Cd in coastal sediments were determined using inductively coupled plasma mass spectrometry (ICP-MS), and the associated risks were evaluated. The findings revealed that metal concentrations were low and remained well below the interim sediment quality guideline (ISQG) and probable effect level (PEL) thresholds. The study results showed low values across all environmental risk indices. Average values were 0.0084 (Ni) to 1.15 (As) for the pollution index, 0.25-0.37 for the modified pollution degree, 0.08-0.15 for the pollution load index, and 0.38 (Ni) to 2.1 (As) for the toxicological risk index. Human health risks were also assessed using non-carcinogenic indicators such as the hazard quotient (HQ) and health risk index (HRI), as well as carcinogenic indicators including cancer risk (CR) and lifetime cancer risk (LCR), through ingestion and dermal exposure pathways. All results indicated minimal contamination, with HRI values below 1. The highest CR values were observed for As (3.08 × 10⁻⁶) in adults and (2.87 × 10⁻5) in children via ingestion. Similarly, the highest LCR values were recorded for As (3.09 × 10⁻⁶) in adults and (2.88 × 10⁻5) in children. These values fall within acceptable limits, indicating no significant environmental or health risks. These findings provide essential baseline data for future monitoring and management efforts, which emphasizes both economic diversification and environmental sustainability. This study therefore serves as a valuable reference for assessing the future impacts of developmental activities along the Arabian Gulf coast.

This study investigates the occurrence and distribution of potentially toxic elements (PTEs) (As, Cd, Cu, Hg, Pb and Zn) in soils collected at playing sites in kindergartens and urban parks in Bratislava city. It was found that the history of urban development was an important factor influencing the occurrence of PTEs in soils. The mean concentrations of PTEs were two times higher (mean of 215 mg/kg for the sum of PTEs) in the oldest urban parts than in urban parts of the city with younger history (mean of 110 mg/kg). Significant positive correlations between the concentrations of Cu, Hg, Pb, Zn and total organic carbon content (Spearman r = 0.23–0.49; α < 0.05–0.001), as well as between the As, Cu, Pb, Zn concentrations and the total Fe content (Spearman r = 0.27–0.55; α < 0.05–0.001) indicated that soil characteristics had also influenced the distributions of PTEs in soils. The values of enrichment factor (EF) and contamination factor (CF) were higher than 1.5 and 1.0, respectively, confirming an anthropogenic contribution to the total concentrations of PTEs in soils. It is expected that there is no non-carcinogenic health risk to children due to exposure to PTEs in soils as the calculated values of hazard quotient (HQ) and hazard index (HI) did not exceed the threshold of 1.0.