Abstract

The accumulation of microplastics (MPs) in terrestrial systems can change the availability of metal(loid)s. The goal of this study was evaluated the effect of 1% (w/w) polyethylene MPs (PE–MPs) on Cu2+ adsorption–desorption processes in two agricultural soils (Andisol: ANDI and Mollisol: MOLL). Batch Cu2+ adsorption–desorption experiments were conducted using AnDI And MOLL soils with and without 1% (w/w) PE–MPs addition. The results revealed, for the very first time, that the adsorption of Cu2+ in both soils with 1% PE–MPs is slightly higher than in the soils without MPs. The adsorption kinetic studies of Cu2+ in soils in the absence And presence of 1% PE–MPs fitted well to the pseudo–second–order model (r2 ≥ 0.940 and ꭓ2 ≤ 14). The Langmuir model described the adsorption isotherms of Cu2+ in both soils in the absence And presence of 1% PE–MPs (r2 ≥ 0.982 and ꭓ2 ≤ 7). According to this model, the maximum adsorption capacity showed the following trend: ANDI + 1% PE–MPs > ANDI > MOLL + 1% PE–MPs > MOLL, reaching values of the order of (mmol kg−1): 51.77 > 48.85 > 39.10 > 37.75, respectively. The Cu2+ desorption percentage showed the following trend MOLL > ANDI + 1% PE–MPs > MOLL + 1% PE–MPs > ANDI, suggesting that Cu2+ desorption from soils by adding 1% PE–MPs was soil type–dependent. This study demonstrated, that PE–MPs could favor the accumulation of Cu2+ in MOLL soils and increase the mobility/availability of Cu2+ in ANDI soils. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.