First Evidence of Existence of Microplastics in Stomach of Some Commercial Fishes in the Lower Gulf of Thailand

Abstract

Microplastics have turned into a key global environmental issue in the current decade because of their marine ubiquity, bioavailability and capability of carrying toxic chemicals. The study focuses, for the first time, on the existence of plastic debris in the stomach contents of some commercially important marine fishes caught from the lower Gulf of Thailand during August to November of 2017. Size and weight range of the samples were 8.5 to 37.1 cm and 8 to 133 g. Results highlighted the ingestion of plastics in the 66.67% samples (110 out of 165 samples). The plastics ingested were microplastics (79.52%) (<5 mm), mesoplastics (20.48%) (5-25 mm). No macroplastic was found during this study since the study dealt with small fishes only. Transparent color plastics were the most dominant colors found in the stomach of fishes examined. Net fibres were the major types of plastics found during this study. There was no relationship found between size of plastics and different biological features of the investigated fishes. These initial findings signify an imperative phase in exploring ecotoxicological perspectives such as the existence and impact of plastic debris on the food chain; the probable effects related to the transmission of contaminants on human health etc.

Not as Bad as It Seems? A Literature Review on the Case of Microplastic Uptake in Fish

“…A different connection was investigated by Azad et al (2018): in their study, the researchers aimed to identify a potential correlation between the mouth size of the fish and the frequency of occurrence of MP in the GIT as well as the size of the MP particles detected. No significant relationship could be attested between the mouth size and either of the MP characteristics.…”

Feeding Habits and the Occurrence of Anthropogenic Debris in the Stomach Content of Marine Fish from Pattani Bay, Gulf of Thailand

“…Microplastics are defined as any plastic particle smaller than 5 mm [ 27 ] and have been widely distributed in the ocean and sediments worldwide in recent years [ 28 ], including all water of pelagic and benthic marine organisms [ 16 , 17 , 29 , 30 , 31 , 32 ]. Microplastics can be found in all living organisms, from tiny animals such as zooplankton [ 31 ], mysid larvae [ 24 ], and bivalves [ 33 , 34 ] to top predators [ 16 , 18 , 21 , 30 , 32 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ]. The first report of microplastics in plankton tows was reported by Carpenter et al [ 43 ] in North America, which later caused concern for massive water bodies [ 44 ].…”

“…In the lower part of the Gulf of Thailand, some sciaenid fish show higher ingestion of mesoplastics than micro- and macroplastics [ 35 ]. Fishing net fibres were the major types of plastic found in the stomachs of some commercial marine fish, and of those, 80% were microplastics (<5 mm), whereas the rest were mesoplastics (5–25 mm) [ 36 ]. In addition, higher ingestion of microplastics was found in some commercial shrimp than in fish, most of the microplastics being fibres from textiles and fishing nets in Thailand [ 39 ].…”

Type and Distribution of Microplastics in Beach Sediment along the Coast of the Eastern Gulf of Thailand

“…Marine plastic waste is not a serious problem just for Thai water, it is also an international critical problem that needs to be addressed and solved promptly. For Thailand, very few previous studies on marine waste and microplastics in the environment and living organisms have been published, such as the studies conducted in biota from Songkhla Lagoon [22], in the economic fish in the lower Gulf of Thailand [23], in sessile invertebrates in the eastern coast of Thailand [24], and shrimp sold in local markets [25]. Very few microplastic studies on the coast such as in sediment from sand and mud beaches in Libong Island, a pristine area in Thailand, are available [26].…”