Quantification of palladium-labelled nanoplastics algal uptake by single cell and single particle inductively coupled plasma mass spectrometry

Environmental context Plastic pollution is widespread and continues to be a major concern, both for the environment and human health. Identifying nanoplastics is challenging but is important to understand how they behave once in the environment. It is shown that a combination of single particle (SP) and single cell (SC) inductively coupled plasma mass spectrometry (ICP-MS) can be used to quantify nanoplastics on a per cell basis after exposure to algal cells. Abstract The effects of plastic pollution on human health and the environment are not well known but there are significant concerns. Although research has increased in recent years, there remain many obstacles to the quantification of nanoplastics. This rapid communication demonstrates that combined single particle (SP)– and single cell (SC)–inductively coupled plasma–mass spectrometry (ICP-MS) provide a novel means to quantify pre-formed core–shell metal–plastic composite nanoparticles when exposed to two freshwater algal cells, Cryptomonas ovata (C. ovata) and Cryptomonas ozolini (C. ozolini). It is shown that individual palladium plastic nanoparticles (Pd NPPs) exposed to algal cells form agglomerates in the cell suspension respectively consisting of 165 and 157 (±3.8) individual Pd NPPs for C. ozolini and C. ovata cells, and that the agglomerates are also cell-associated with 1.75–1.85 agglomerates per cell.