Short Depuration of Oysters Intended for Human Consumption Is Effective at Reducing Exposure to Nanoplastics

Abstract

Nanoplastics (NPs; <1 μm) have greater availability to marine organisms than microplastics (1–5000 μm). Understanding NP uptake and depuration in marine organisms intended for human consumption is imperative for food safety, but until now it has been limited due to analytical constraints. Oysters (Crassostrea gigas) were exposed to polystyrene NPs doped with palladium (Pd), allowing the measurements of their uptake into tissues by inductively coupled plasma mass spectrometry (ICP-MS) combined with electron microscopy. Oysters were exposed for 6 days (d) to “Smooth” or “Raspberry” NPs, followed by 30 d of depuration with the aim of assessing the NP concentration in C. gigas following exposure, inferring the accumulation and elimination rates, and understanding the clearance of Pd NPs during the depuration period. After 6 d, the most significant accumulation was found in the digestive gland (106.6 and 135.3 μg g–1 dw, for Smooth and Raspberry NPs, respectively) and showed the most evident depuration (elimination rate constant K Smooth = 2 d–1 and K Raspberry = 0.2 d–1). Almost complete depuration of the Raspberry NPs occurred after 30 d. While a post-harvesting depuration period of 24–48 h for oysters could potentially reduce the NP content by 75%, more research to validate these findings, including depuration studies of oysters from the field, is required to inform practices to reduce human exposure through consumption.

Surface-Charge-Driven Ferroptosis and Mitochondrial Dysfunction Is Involved in Toxicity Diversity in the Marine Bivalve Exposed to Nanoplastics

“…Sexually mature clams were maintained in ASW following the procedures described previously. 62 The physical and chemical properties of ASW were kept constant, that is, pH 8.0 ± 0.5, at 30 ± 0.5 ‰ salinity and 7.9 ± 0.6 mg/L dissolved oxygen concentration at 16 ± 1 °C, during overall acclimation and exposure period. More details are given in Supporting Note 2.…”

“…philippinarum (26 ± 2.5 mm) was obtained from an aquaculture farm (Guangdong province, China) and acclimated in the laboratory for 2 weeks. Sexually mature clams were maintained in ASW following the procedures described previously . The physical and chemical properties of ASW were kept constant, that is, pH 8.0 ± 0.5, at 30 ± 0.5 ‰ salinity and 7.9 ± 0.6 mg/L dissolved oxygen concentration at 16 ± 1 °C, during overall acclimation and exposure period.…”

Nanoplastics prepared with uniformly distributed metal-tags: a novel approach to quantify size distribution and particle number concentration of polydisperse nanoplastics by single particle ICP-MS

“…12 This could be an issue for human health if MP accumulation occurs in marine species consumed by humans. 13–16 The uptake of MPs by edible plants is also a public health and food security issue, 17 and consumption of MPs through ingestion of particle-containing food has been cited as a threat to global food security and human health.…”

Near-Infrared-II In Vivo Visualization and Quantitative Tracking of Micro/Nanoplastics in Fish

“…The use of commercially available fluorescently labeled polystyrene (PS) particles has been a prevalent technique so far to characterize the uptake, tissue distribution and translocation of MNPs in aquatic organisms . However, there are many disadvantages limiting its application, including autofluorescence of the organism, high background fluorescence signal interference, high detection limit, and false positive results caused by fluorophore release. , In addition, due to the internal light diffraction and scattering of tissues, the resolution of biological imaging and the range of applicable organisms was limited (e.g., phytoplankton, zooplankton, fish larval, cell, and transparent organisms), and the deep tissue cannot be realistically measured. , A more recent approach is to measure the metal-doped plastic particle (e.g., palladium-doped NPs) after digesting the tissue of organisms, but the loss of latent spatial information is not conducive to in situ observation of the behavior of MNPs in vivo . To date, the challenge of tracking MNPs in vivo and the need for low detection limits have hindered their measurement at environmentally relevant concentrations.…”

“…22,23 In addition, due to the internal light diffraction and scattering of tissues, the resolution of biological imaging and the range of applicable organisms was limited (e.g., phytoplankton, zooplankton, fish larval, cell, and transparent organisms), and the deep tissue cannot be realistically measured. 24,25 A more recent approach is to measure the metal-doped plastic particle (e.g., palladiumdoped NPs) after digesting the tissue of organisms, 26 but the loss of latent spatial information is not conducive to in situ observation of the behavior of MNPs in vivo. To date, the challenge of tracking MNPs in vivo and the need for low detection limits have hindered their measurement at environmentally relevant concentrations.…”