Do polyethylene microplastic beads alter the intestinal uptake of Ag in rainbow trout (Oncorhynchus mykiss)? Analysis of the MP vector effect using in vitro gut sacs

Khan, FR, Boyle, D, Chang, E and Bury, Nic (2017) Do polyethylene microplastic beads alter the intestinal uptake of Ag in rainbow trout (Oncorhynchus mykiss)? Analysis of the MP vector effect using in vitro gut sacs. Environmental Pollution, 231 (1). pp. 200-206. ISSN 0269-7491

[img] Text
Khan et al. 2017 Environ Poll FINAL.pdf - Accepted Version
Restricted to Repository staff only until 1 December 2019.

Download (1MB) | Request a copy

Abstract

Microplastic (MP) vector effects have been well described in the literature but surprisingly little is in known about the impact of MPs on the intestinal uptake of contaminants. The present study aimed to determine whether the intestinal fate of Ag was affected by the presence of polyethylene MP beads. Ag (added as 110mAg) was introduced into the lumen of rainbow trout (Oncorhynchus mykiss) anterior/mid-intestine gut sac preparations as Ag only, Ag and MPs (co-exposure) and Ag-incubated MPs (where Ag was adsorbed to the MP). Results show that after 3 h exposure the distribution of accumulated Ag between the four intestinal compartments (mucus layer, mucosal epithelium, muscle layer and serosal saline) was not affected by either MP condition when compared to Ag alone (p>0.05, One way ANOVA). Across all treatment groups mucus layer binding dominated (54.2-72.6 %) whereas relatively little Ag was transported to the blood compartment (i.e. combined muscle layer and serosal saline compartments, 8.5-15.0 %). Accompanying adsorption/desorption studies were performed in relevant media. Over 24 h, 60.6 ± 2.9% of the available Ag in artificial freshwater adhered to the surface of the PE MPs. In pH adjusted luminal fluids (pH 2.2, 4.1, 7.4 and 9.8) that span the range of conditions encountered within the rainbow trout digestive tract, there was almost complete dissociation at acid pH within 3 h (<2% remaining on MPs at both pH 2.2 and pH 4.1). Such pHs are typical of piscine stomach. Based on our finding we suggest that following the ingestion of MPs with adsorbed pollutants, desorption would occur prior to entering the site of uptake. The MPs themselves have no impact on the trans-epithelial transport of the contaminant, but the net result of the MP vector effect is to potentially introduce labile contaminant forms into the intestine.

Item Type: Article
Uncontrolled Keywords: Adsorbed pollutants; Intestinal metal uptake; In vitro gut sacs; Microplastic vector-effect
Subjects: Q Science > Q Science (General)
Q Science > QH Natural history
Q Science > QH Natural history > QH301 Biology
Q Science > QL Zoology
Divisions: Faculty of Health & Science > Department of Science & Technology
Depositing User: Nic Bury
Date Deposited: 24 Aug 2017 13:41
Last Modified: 20 Nov 2017 11:12
URI: http://oars.uos.ac.uk/id/eprint/239

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year