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Spatiotemporal Variation of Heavy Metals and Pollution Indices in Groundwater Around Al-Diwaniyah Open Dump

Aziz Fatin F., Hussain Entessar Kareem

Journal of Ecological Engineering

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2023

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Vol. 24, nr 8

106--117

EN

Potential environmental hazards associated with heavy metals have been reported at Al-diwaniyah open dump in Iraq. Therefore, the levels of heavy metals and their spatial and temporal variability have been studied, in addition to pollution indices (HPI, HEI, Cd) to achieve environmental management and sustainability. Concentrations of seven heavy metals in groundwater wells at various distances around dumpsite were analyzed for the period 2022–2023 using atomic absorption spectrophotometer. Results revealed that heavy metals levels in samples examined decreased with the distance from the dumpsite W1>W2>W3 and it followed this pattern: Cd < Ni < Cr < Pb < Cu < Fe < Zn, with average concentrations in dry and rainy seasons were Zn (0.641,0.305), Fe (0.199,0.375), Cu (0.208,0.068), Pb (0.035,0.117), Cr (0.031,0.073), Ni (0.106,0.055), Cd (0.023,0.0095). On one hand, seasonal variation showed that 57.14% of heavy metals were raising in the dry season, and on the other, pollution indices showed that the groundwater taken from the W1 site was heavily polluted and unfit for consumption, while the other two sites were in low pollution category, which showed little impact of waste dumps on groundwater in these sites. Analysis results indicated that groundwater is appropriate for drinking purposes compared to the permissible limits of WHO/IQS, apart from those taken from site W1. All wells also provide water suitable for irrigation purposes based on the guidelines of the Food and Agriculture Organization (FAO). The Statistical analysis demonstrated a strong correlation between some heavy metals, in addition to the influence of sampling sites on heavy metal levels. It is recommended to expand this study to include additional regions in order to provide more environmental monitoring for groundwater and examine its potential human health risks in the study region, construct an engineering landfill equipped with leachate collector system, moreover, systematic treatment of heavy metals concentrations should be carried out regularly.

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Groundwater Contamination and Health Risk Evaluation of Naturally Occurring Potential Toxic Metals of Hatiya Island, Bangladesh

Rahman Mahfuzur, Khan Md. Sadril Islam, Hossain Mohammad Sabbir, Hossain Md. Imam Shohel, Hasan Mahmudul, Hamli Hadi, Mustafa M. Golam

Journal of Ecological Engineering

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2022

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Vol. 23, nr 6

223--236

EN

Groundwater meets the majority portion of drinking water needs, particularly in the rural area of Bangladesh. Groundwater has been continuously contaminated by potentially harmful metals as a result of natural processes as well as some anthropogenic activities, creating a variety of health impacts. The current research aimed to evaluate the naturally occurring level of metal contamination and the human health risk associated with deep groundwater in the Hatiya Island. Because of the arsenic, iron, and salinity problem in shallow groundwater, the inhabitants of the Hatiya Island use deep groundwater. During the field investigation, no shallow tubewells were observed; therefore, only deep groundwater samples were collected. The total sample size collected throughout the Hatiya island was 17. Five metals (Zn, Fe, Mg, Mn, and Cu) were analyzed using an Atomic Absorption Spectrophotometer (AAS). The concentrations of studied potential risky metals were ranked as follows: Mg > Zn > Fe >Mn> Cu. The detected values of all metals except Fe were found within the drinking water limits of WHO (2017), BIS (2012), and BDWS (1997), where only 29.41% of the Fe sample exceeded the standard drinking limits. According to the metal evaluation index (MEI) and degree of contamination (Cd), the groundwater of the study area is free from contamination but the metal pollution index (MPI) and nemerow pollution index (NI) exhibited little pollution in the mid-western part of the study area. The hazard quotient (HQ) values revealed no oral and dermal health risk for individual metals (Cu, Zn, Fe, Mn). On the other hand, the hazard index (HI) values exhibited no risk for combined metals as none of the values exceeded the safety limit value of 1. According to the HQ and HI results, the deep groundwater on Hatiya Island is non-carcinogenic and risk-free for children and adults. However, children were more susceptible to oral health risks than adults. In contrast, adults were more vulnerable to dermal health risks than children.

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Ecological assessment of heavy metals in the grey mangrove (Avicennia marina) and associated sediments along the Red Sea coast of Saudi Arabia

Alzahrani D. A., Selim E.-M. M., El-Sherbiny M. M.

Oceanologia

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2018

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No. 60 (4)

513--526

EN

Mangroves play an integral role as a metal accumulator in tropical and subtropical marine ecosystems. Twenty-one sets of sediment samples and portions of mangroves were collected along the Saudi Arabian coast of the Red Sea to assess the accumulation and ecological risks of heavy metals. Results showed that the following mean concentrations of heavy metals in sediments: Cr (46.14 μg g−1 ± 18.48) > Cu (22.87 μg g−1 ± 13.60) > Ni (21.11 μg g−1 ± 3.2) > Pb (3.82 μg g−1 ± 2.46) > Cd (0.75 μg g−1 ± 0.87). The maximum concentrations of the studied metals were above the threshold effect level, indicating a limited impact on the respective ecosystems. The maximum concentration of Cd exceeded its toxic effect threshold, revealing a harmful risk to biota in the sediments. Based on metallo-phytoremedation, biological concentration factors were >1, suggesting that Avicennia marina can accumulate heavy metals, especially Cr and Pb. The translocation factor was above the known worldwide average. The geo-accumulation index revealed that sediments in mangrove areas ranged from moderately to heavily contaminated with Cd at Al-Haridhah and moderately contaminated at South Jeddah, Rabigh, Duba, and the wastewater treatment station near Jazan. The ecological risk index revealed that Cd could pose a relatively very high risk to the mangrove ecosystem. The present study emphasized the possibility of establishing a framework for the management of the coastal aquatic ecosystems along the Red Sea coast of Saudi Arabia.