Assessment of the Abundance and Characteristics of Microplastics in the Effluent of the Urban Wastewater Treatment Plant in Zabol

Miri, Mohadeseh; Pakzad Toochaei, Sahel; Khandan Barani, Hashem

Volume 13, Issue 3 (12-2025) J Environ Health Eng 2025, 13(3): 345-356 | Back to browse issues page

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Miri M, Pakzad Toochaei S, Khandan Barani H. Assessment of the Abundance and Characteristics of Microplastics in the Effluent of the Urban Wastewater Treatment Plant in Zabol. J Environ Health Eng 2025; 13 (3) :345-356
URL: http://jehe.abzums.ac.ir/article-1-1136-en.html

Assessment of the Abundance and Characteristics of Microplastics in the Effluent of the Urban Wastewater Treatment Plant in Zabol

Mohadeseh Miri ^*¹

, Sahel Pakzad Toochaei²

, Hashem Khandan Barani³

1- Department of Natural Ecosystems Management, Hamoun International Wetland Institute, Research Institute of Zabol, Zabol, Iran , mirimohadesea@yahoo.com
2- Department of Natural Ecosystems Management, Hamoun International Wetland Institute, Research Institute of Zabol, Zabol, Iran
3- Department of Aquatic Sciences, Hamoun International Wetland Institute, Research Institute of Zabol, Zabol, Iran

Abstract: (28 Views)

Background: Microplastic pollution has emerged as a significant environmental crisis, posing a serious challenge to human health and ecosystem sustainability, particularly within urban wastewater treatment systems. This study aimed to investigate the abundance, physical characteristics, and chemical composition of microplastics in the effluent of the Zabol urban wastewater treatment plant.
Materials and Methods: Sampling of the treated effluent was conducted in the winter of 2024. Three samples, each with a volume of 10 liters, were collected from the effluent of the wastewater treatment plant. For microplastic separation, the samples were passed through sieves of various mesh sizes, followed by chemical digestion and density-based separation. Microplastics were identified and categorized using optical microscopy and Fourier-transform infrared spectroscopy (FTIR).
Results: The results indicated that the highest mean abundance was 26.38 ± 1.08 microplastics per liter, with particle sizes ranging from 45 to 425 μm in the treated effluent. The results of the ANOVA test showed that film particles, with a mean abundance of 27.58 ± 1.08 microplastics per liter, accounted for the largest proportion compared to other forms (fibers, fragments, and foams), with a statistically significant difference (p < 0.05). FTIR analysis revealed a considerable diversity of polymers among the detected particles. Among them, polyethylene (PE) showed the highest relative abundance (21.46 ± 0.9), representing the dominant polymer type.
Conclusion: The results of this study provide a clear picture of the status of microplastics in the effluent of this wastewater treatment plant. They also highlight the necessity of continuous monitoring, identification of potential sources, management of lightweight plastic waste, reduction of single-use packaging consumption, and the need for further studies on the pathways and environmental impacts of microplastics in arid and water-scarce regions, especially due to the continuous use of this effluent for irrigation of surrounding agricultural lands.

Keywords: Microplastic, Wastewater treatment, Polyethylene, Sistan, FTIR Spectroscopy

Full-Text [PDF 2846 kb] (12 Downloads)

Type of Study: Research | Subject: Special
Received: 2025/09/21 | Accepted: 2025/11/8 | Published: 2025/12/13

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