Microplastics in the digestive tract of fish from the estuary Ciénaga Grande de Santa Marta, Colombia

Ernesto Alejandro Calderon Quintana & Peter Hansen

Studenteropgave: Masterafhandling

Abstrakt

Once believed that plastic litter was mostly an aesthetic issue, recent research has shown that it is broken down to smaller pieces, termed microplastics (MPs) by UV-radiation, hydrolysis and physical forces. Microplastics are no longer regarded as a marine issue and furthermore MPs have now been shown to be a persistent environmental hazard affecting biota at all compartments of the environment and should be considered a serious concern.

This study investigated the presence of microplastics in the digestive tract of 140 fish caught in the estuary of La Ciénaga Grande de Santa Marta in northern Colombia. La Ciénaga Grande de Santa Marta is a Ramsar site and an UNESCO biosphere reserve of the largest artisanal fisheries in Colombia, supporting more than 3500 fishermen daily. The fish were of four different fish species, Mugil incilis, Eugerres plumieri, Caquetaia kraussii and Caranx hippos and three different feeding strategies, namely detritivore, carnivore and omnivore. Dissected digestive tracts were dissolved in a 10M NaOH solution and kept at 600 C for 48 hours and then filtered through 100µm metal mesh. All samples were first visual exanimated with a microscope and suspected microplastics were measured with Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy. Microplastics were confirmed in 5-22% of fish across the fish species. However, there was no apparent relationship between microplastics prevalence and factors of feeding strategies, habitat or size. Our study contributes to the ongoing global effort to document MPs in the environment and associated biota.
Our study contributes to the ongoing global effort to document MPs in the environment and associated biota and is the first to report the presence of MPs in the important estuary of La Ciénaga Grande de Santa Marta. We recommend further investigation of the presence of MPs in the estuary and suggest a standardized method for extracting MPs from the digestive tract of fish to ensure a better comparison of the abundance of MPs.

UddannelserMiljøbiologi, (Bachelor/kandidatuddannelse) Kandidat
SprogEngelsk
Udgivelsesdato2018
Antal sider48
VejledereFarhan Khan & Kristian Syberg