en Environmental Health, Sciences, and Engineering Environmental Health, Sciences, and Engineering پژوهشي Original Article <div style="text-align: justify;"><span style="line-height:1;"><span style="font-size:14px;"><span style="font-family:Times New Roman;"><b><span style="color:black">Background:</span></b><span style="color:black"> Earthworms are known to respond quickly to various environmental stressors. The present study aimed to investigate the relationship between varying levels of tire-derived microplastic (TMP) exposure and the accumulation of specific heavy metals in the earthworm <i>Eisenia fetida</i>.</span><br> <b><span style="color:black">Methods: </span></b><span style="color:black">We assessed the accumulation of arsenic (As), cadmium (Cd), chromium (Cr), tin (Sn), aluminum (Al), lead (Pb), zinc (Zn), and molybdenum (Mo) in <i>Eisenia fetida</i> through a 14-day controlled exposure to TMP concentrations of 0, 10, 50, 100, and 200 mg/g dry artificial soil, with three replications. </span><br> <b><span style="color:black">Results:</span></b><span style="color:black"> The accumulation of Cr, Sn, Al, Pb, Zn, and Mo increased significantly with TMP concentrations exceeding 100 mg/g. The concentration of Cd remained statistically similar in TMP concentrations above 50 mg/g, while a significant increase in Zn concentration was observed at TMP levels higher than 100 mg/g. The correlation coefficients between Potentially Toxic Elements (PTEs) concentration in the species and inhabited soil were negative and statistically significant for Cd (<i>p-value</i> < 0.05), Al (<i>p-value</i> < 0.01), and Mo (<i>p-value</i> < 0.05), suggesting a depletion of PTEs from the soil as the earthworms accumulated higher concentrations.&nbsp; Maximum levels reached 130.44 &plusmn; 4.43 &mu;g/L for Sn, 2.46 </span><span style="color:black">&plusmn;</span><span style="color:black"> 1.74 mg/L for Zn, and 0.057 &plusmn; 0.006 mg/L for Cr in the 200 mg TMP exposures.</span><br> <b><span style="color:black">Conclusion: </span></b><span style="color:black">This study used artificial soil samples, and the impact of soil physicochemical characteristics on the mobility and bioavailability of MP-associated PTEs remains an area open for future investigation.</span></span></span></span></div> Potentially toxic elements (PTEs), Microplastic, Earthworm, Controlled exposure, Eisenia fetida, 27 35 http://jhehp.zums.ac.ir/browse.php?a_code=A-10-658-1&slc_lang=en&sid=1 Najla Hamidianfar hamidi.najla1992@gmail.com 100319475328460015663 100319475328460015663 No Department of Environmental Science and Engineering, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran. Atefeh Chamani atefehchamani@yahoo.com 100319475328460015664 100319475328460015664 Yes Department of Environmental Science and Engineering, Waste and Wastewater Research Center, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran. Mitra Ataabadi mitra_ataabadi@yahoo.com 100319475328460015665 100319475328460015665 No Department of Soil Science, College of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran. Rasool Zamani-Ahmadmahmoodi rasoolzamani@yahoo.com 100319475328460015666 100319475328460015666 No Department of Fisheries and Environmental Sciences, Faculty of Natural Resources and Earth Science, Shahrekord University, Shahrekord, Iran.