Effect of Microplastic on the Gills of the Shore Crab Carcinus maenas

Abstract

Microscopic plastic debris (microplastics, <5 mm in diameter) is ubiquitous in the marine environment. Previous work has shown that microplastics may be ingested and inhaled by the shore crab Carcinus maenas, although the biological consequences are unknown. Here, we show that acute aqueous exposure to polystyrene microspheres (8 μm) with different surface coatings had significant but transient effects on branchial function. Microspheres inhaled into the gill chamber had a small but significant dose-dependent effect on oxygen consumption after 1 h of exposure, returning to normal levels after 16 h. Ion exchange was also affected, with a small but significant decrease in hemolymph sodium ions and an increase in calcium ions after 24 h post-exposure. To further asses the effects on osmoregulation, we challenged crabs with reduced salinity after microplastic exposure. Neither microspheres nor natural sediments altered the crab's response to osmotic stress regardless of plastic concentration added. Carboxylated (COOH) and aminated (NH 2 ) polystyrene microspheres were distributed differently across the gill surface, although neither had a significant adverse impact on gill function. These results illustrate the extent of the physiological effects of microplastics compared to the physiological resilience of shore crabs in maintaining osmoregulatory and respiratory function after acute exposure to both anthropogenic plastics and natural particles.

Toward the Development and Application of an Environmental Risk Assessment Framework for Microplastic

“…It is likely that organisms will have varying thresholds in relation to changes in turbidity (Newcombe and Macdonald 1991;Gordon and Palmer 2015); therefore, deriving thresholds based on species sensitivity for suspended solids could provide useful insight in defining if effects observed are intrinsic to the particle or are representative of an intrinsic response of the organism to particles in general (Ogonowski et al 2018;ECETOC 2019). Although a few studies have addressed this specific question (Casado et al 2013;Ogonowski et al 2016;Watts et al 2016;Straub et al 2017), more research in defining appropriate particle controls appears warranted, which may help address concerns related to exposure to microplastic particles and responses that an organism may have to any particle, naturally occurring or synthetically derived (Ogonowski et al 2018;ECETOC 2019).…”

Interactions of Microplastics with Freshwater Biota

“…The respiratory uptake and the following adhesion of MPs to the gills might influence the branchial function. For instance, Watts et al [58] found a significantly decreased oxygen consumption of MP-exposed crabs after 1 h and observed some adaptation as oxygen consumption returned to normal after 16 h.…”

Characteristics, seasonal distribution and surface degradation features of microplastic pellets along the Goa coast, India

“…In addition to blocking the digestive tract and preventing normal feeding, microplastic ingestion can damage the cells and tissues of organisms such as blue mussels (von Moos et al, 2012), and crustaceans (Laist, 1987). Watts et al (2016) found that the ingested microplastics by shore crabs (Carcinus maenas) affect the respiratory function. Fishes swallow MPPs (Wright et al, 2013a), which may severely damage and/or kill fishes.…”