Detection of nanoparticles in edible plant tissues exposed to nano-copper using single-particle ICP-MS

Abstract

The increasing use of nanopesticides has raised concerns about their effects on crop plants and the impact of human health as well as ecological effects. While increased uptake of metal ions has been observed before, to date, very few studies have demonstrated the presence of nanoparticles in edible tissues. Singleparticle inductively coupled plasma-mass spectrometry (sp-ICP-MS) has been suggested as a powerful tool to detect inorganic nanoparticles (NPs) in environmental samples. Here, we exposed edible plant tissues from lettuce, kale, and collard green to nano-CuO, simulating its use as a nanopesticide. We applied sp-ICP-MS to demonstrate the presence of nanoparticles, both in the water used to rinse crop leaf surfaces exposed to nano-CuO and within the leaf tissues. Lettuces retained the highest amounts of nCuO NPs on the leaf surface, followed by collard green and then kale. Surface hydrophilicity and roughness of the leaf surfaces played an important role in retaining nano-CuO. The results indicate that most of the nanoparticles are removed via washing, but that a certain fraction is taken up by the leaves and can result in human exposure, albeit at low levels.

Multi-technique approach to study the stability of silver nanoparticles at predicted environmental concentrations in wastewater

“…The instrument was equipped with an auto sampler and a standard peristaltic pump, standard glass concentric nebulizer, quartz spray chamber and quartz torch, standard nickel sampling and skimmer cones. Analyses were performed in time-resolved analysis (TRA) mode using a dwell time of 100 ms per point without settling time between measurements, as previously reported (Keller et al, 2018;Montaño et al, 2014). The transport efficiencies for Au and Ag are almost identical; however, Au NPs are more stable than nano-Ag (Wimmer et al, 2018).…”

Interaction of Copper-Based Nanoparticles to Soil, Terrestrial, and Aquatic Systems: Critical Review of the State of the Science and Future Perspectives

“…Among all three vegetables, lettuce retained the highest amount of CuO-NPs on leaf surface even after washing. For this retention, the varying degrees of leaf surface roughness and hydrophilicity among the tested vegetables have been suggested to play an important role in holding CuO-NPs (Keller et al 2018). Overall the data from these studies indicate that certain fractions of CuO-NPs are taken up by plants which may result in undesirable accumulation in edible plant tissues ultimately exposing humans via the food chain.…”

“…In a very recent study, Keller and co-workers exposed leaf tissues of lettuce, collard green, and kale to nano-CuO and detected CuO-NPs in leaf surfaces by use of single particle inductively coupled plasmon mass spectroscopy (sp-ICP-MS) (Keller et al 2018). Among all three vegetables, lettuce retained the highest amount of CuO-NPs on leaf surface even after washing.…”

Omics to address the opportunities and challenges of nanotechnology in agriculture

“…Plants' response to ENMs is highly varied and dependent on environmental conditions, species and age, exposure dose and duration, and ENM properties, like composition, size, surface coating, morphology, stability, or dissolution, among other factors (Ma et al, 2018). Researchers have employed advanced electron microscopy, synchrotron-based imaging techniques and single particleinductively coupled plasma mass spectrometry (sp-ICP-MS) to locate ENMs in plant tissues upon foliar or root exposure (Avellan et al, 2019;Castillo-Michel et al, 2017;Keller et al, 2018). Such studies have effectively proved that some ENMs enter through roots or leaves and can cross biological barriers to transport within plants, unlike their conventional analogues (Ma et al, 2015;Sanzari et al, 2019).…”