Microplastics

13 pages, 2102 KiB

Open AccessArticle

Quantification of Very Low Concentrations of Colloids with Light Scattering Applied to Micro(Nano)Plastics in Seawater

by Gireeshkumar Balakrishnan, Fabienne Lagarde, Christophe Chassenieux and Taco Nicolai

Microplastics 2023, 2(2), 202-214; https://doi.org/10.3390/microplastics2020016 - 02 Jun 2023

Cited by 1 | Viewed by 1880

The detection and quantification of micro(nano)plastics in the marine environment are essential requirements to understand the full impacts of plastic pollution on the ecosystem and human health. Here, static light scattering (SLS) and dynamic (DLS) light scattering techniques are assessed for their capacity to detect colloidal particles with diameters between d = 0.1 and 0.8 µm at very low concentrations in seawater. The detection limit of the apparatus was determined using model monodisperse spherical polystyrene latex particles with diameters of 0.2 µm and 0.5 µm. It is shown that the concentration and size of colloids can be determined down to about 10⁻⁶ g/L. Light scattering measurements on seawater obtained from different locations in Western Europe show that colloidal particles were detected with DLS in seawater filtered through 0.8 µm pore size filters. The concentration of these particles was not higher than 1 µg/L, with an average diameter of about 0.6 µm. We stress that these particles are not necessarily plastic. No particles were detected after filtration through 0.45 µm pore size filters. Full article

(This article belongs to the Special Issue Monitoring, Detection and Mitigation of Micro and Nanoplastics)

► Show Figures

Graphical abstract

10 pages, 3135 KiB

Open AccessArticle

Impact of Degradation of Polyethylene Particles on Their Cytotoxicity

by Yudai Ikuno, Hirofumi Tsujino, Yuya Haga, Haruyasu Asahara, Kazuma Higashisaka and Yasuo Tsutsumi

Microplastics 2023, 2(2), 192-201; https://doi.org/10.3390/microplastics2020015 - 22 May 2023

Cited by 4 | Viewed by 1955

Abstract

Microplastics are ubiquitous in the environment, including in the ocean, soil, and air. Therefore, there are concerns regarding human exposure. Since it is known that the surface of microplastics in various environments is chemically deteriorated by external factors such as ultraviolet rays and waves, it is essential to evaluate the biological effects of degraded microplastics. In this study, we experimented by accelerating the degradation of polyethylene (PE) using vacuum ultraviolet light and prepared PE samples with different degrees of degradation. Then, we evaluated the effects of undegraded and variously degraded PE on cells using cytotoxicity tests. Based on the cytotoxicity test results, we saw a tendency for increased cytotoxicity with increasing degradation. Therefore, this study substantially links the deterioration of microplastics with their biological effects. Full article

(This article belongs to the Collection Current Opinion in Microplastics)

► Show Figures

Figure 1

10 pages, 1292 KiB

Open AccessArticle

Microplastic Pollution in Sea Turtle Nests on the Beaches of Nautla and Vega de Alatorre, Veracruz

by Belem Anahy Estrella-Jordan, Fabiola Lango-Reynoso, María del Refugio Castañeda-Chávez, Jesús Montoya-Mendoza and David Reynier-Valdes

Microplastics 2023, 2(2), 182-191; https://doi.org/10.3390/microplastics2020014 - 12 May 2023

Cited by 3 | Viewed by 2875

Abstract

Microplastic contamination has become a topic of interest and concern worldwide due to its persistence and the possible effects it may cause to the environment. When microplastics are present, they can alter their physical properties, negatively affecting the surrounding fauna, such as sea turtles that use the beaches to nest in the sand. In this study, the exposure of sea turtle nests to microplastics on the beaches of Nautla and Vega de Alatorre, Veracruz, one of the main nesting areas for the green turtle Chelonia mydas, as well as Kemp’s ridley turtle Lepidochelis kempii from the Gulf of Mexico, was determined. Sand samples were obtained directly from the nests in situ on four beaches in the area and from two nesting pens, revealing the presence of microplastics in 100% of the nests in situ, with an average abundance of 2.43 ± 2.66 #MP/kg SS and a concentration of 0.00672 ± 0.02286 mgMP/kg SS, predominantly the form of foam, white in color, and from 1 to 2 mm in size. Full article

(This article belongs to the Special Issue Microplastics in Marine Environment)

► Show Figures

Graphical abstract

14 pages, 44278 KiB

Open AccessArticle

Microplastic Contamination in Cultured Mussels and Pearl Oysters in Greece

by Stefania M. Manolaki, Dimitra Chatzivasileiou, Maria Lampa, Panagiotis D. Dimitriou, Aggelos Philippidis, Ioannis Karakassis and Nafsika Papageorgiou

Microplastics 2023, 2(2), 168-181; https://doi.org/10.3390/microplastics2020013 - 03 Apr 2023

Cited by 2 | Viewed by 2437

Abstract

Τhis study aims to measure the abundance of microplastic (MP) particles in the soft tissue of mussel (Mytilus galloprovincialis) and pearl oyster (Pinctada imbricata radiata) specimens. Samples were collected at four sites in Greece (Sagiada, Malesina, Elounda, Rhodes) from wild and farmed populations. The identification of MPs was accomplished by Raman spectroscopy. Comparisons were made between the two different species where the two species co-existed (Malesina), between the four study sites (five sampling stations) in relation to P. imbricata radiata individuals, and also in every station for the different MP types found. For the specimens from Malesina, M. galloprovincialis had more MPs in their soft tissue compared to P. imbricata radiata. Microfibers were found in abundance in M. galloprovincialis, while microfragments were found in P. imbricata radiata specimens. The main MP type found in P. imbricata radiata specimens was microfragments in all five sampling stations, and ranged between 1.54 ± 0.63 (Rhodes-baskets) and 3.56 ± 0.35 (Sagiada) MP particles/g. While the samples of mussels and pearl oysters were similar in age, the differences found in the concentrations of MPs appears to be due to their different farming methods and location characteristics concerning the five sampling stations of pearl oysters. This study indicates that the culturing system does not affect MP concentration in bivalves, and further investigation is needed to find the most appropriate method to limit and reduce MPs that end up in the farmed organisms. Full article

(This article belongs to the Collection Current Opinion in Microplastics)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Microplastics, Volume 2, Issue 2 (June 2023) – 4 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI