How do fish consume microplastics? An experimental study on accumulation pattern using Nile tilapia (Oreochromis niloticus).

The aim of this study was to investigate microplastic (MP) exposure by Nile tilapia (Oreochromis niloticus) in laboratory conditions. A total of 150 tilapia fishes were equally distributed randomly in 15 different glass tanks with five experimental conditions. Observed results depicted that the presence of MPs in different organs was mainly accumulated from the fish feed rather than externally added MPs in the culture tanks. It was also revealed that the gastrointestinal tract (GIT) was found to be the most susceptible to MPs accumulation followed by gills and muscles in order. However, muscle contained the least size of MPs followed by GITs and gills. A statistical test showed significant correlations among the average length and weight of fish with MP exposure. A filamentous shape was found to be dominant in both GITs and gills while fragment shape was dominant in muscles. FTIR results revealed a total of 12 different polymers in the fish of which two polymers (polyvinyl alcohol and ethylene vinyl acetate) were not detected in the feed-only tanks. Polypropylene (PP) and polyethylene terephthalate (PET) were found to be dominant polymers in all the experimental GIT, gills, and muscle organs. FESEM results indicated the presence of different textures including cracks, edges, flakes, scratches, grooves, and adhering particles. EDX results exhibited the presence of Na, Si, K, Ni, Cu, Zn, As, and Cd in the analyzed samples that may pose additional health risks. Thus, this study could act as baseline data for laboratory-based studies of aquaculture species in future research.

Microplastics contamination in fish feeds: Characterization and potential exposure risk assessment for cultivated fish of Bangladesh.

Fish feed is becoming an increasingly vital source of nourishment for farmed fish, which are mainly coming from marine fish and agricultural sources. Anthropogenic particles, such as microplastics, are abundant in both marine fish and agricultural byproducts that are utilized to make fish feed. This study investigated whether fish feed could be a source of microplastic contamination, and revealed that a 20 weeks adult farmed tilapia fish might consume up to 268.45 ± 1.438 microplastic particles via fish feed where finisher type feeds were found to be mostly contributory in this number. The microplastics were initially observed with a stereomicroscope and FESEM-EDS. Polymeric composition of microplastics was determined to be polypropylene (PP), nylon-6 (NY-6), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl alcohol (PVA), polyethylene (PE), high- and low-density polyethylene (HDPE, LDPE), ethylene vinyl acetate (EVA), polycarbonate (PC), poly vinyl acetate (PVAc), poly urethane (PU) and polyvinyl chloride (PVC) by FTIR. Results also revealed that the size of microplastic particles in all fish feed ranged from 14 µm to 4480 µm, with 550 ± 45.45 to 11,600 ± 56.1 microplastic particles/kg of fish feed. The FESEM-EDS data demonstrated to overlook the microplastic surface along with attachment of heavy metals onto that surface such as Pb, Ni, and Co in finisher type feed that could create additional health risks.

Occurrence of microplastics in tap and bottled water, and food packaging: A narrative review on current knowledge.

Nowadays, microplastic has been detected in many environmental samples, including aquatic and terrestrial environments. However, few studies recently have addressed their attention to microplastic contamination in different drinking sources and food packages. This review paper has narrated those few findings in brief. Literature showed that different pieces of microplastic fragments, e.g., polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene (PE), high-density polyethylene (HDPE), low-density polyethylene (LDPE), etc. are detected in plastic drinking bottle, tap water, and food packaging containers. Microplastic fragmentation may be associated with mechanical stress, UV radiation, low plastic material quality, aging factor, and atmospheric deposition. Besides these, microplastic is a hub of different chemical compounds and can also retain other complex materials from the surroundings. This makes the microplastic contamination even more complicated and difficult to detect them accurately in a single method. Additionally, one of the common practices at the community level is the long-time repeated usage of plastic drinking bottles and food boxes that subsequently cause microplastic leaching and potential health threats to consumers. This narrative study summarizes the current scenario of microplastic contamination from drinking bottles and food containers and emphasizes doing more quality research in this subtle but highly imposed field to understand potential exposure better.

Risk assessment of heavy metals in marine fish and seafood from Kedah and Selangor coastal regions of Malaysia: a high-risk health concern for consumers.

The heavy metals namely Fe, As, Cu, Cd, and Pb were investigated in two marine fishes silver pomfret (Pampus argentus) and torpedo scad (Megalaspis cordyla), and three seafoods sibogae squid (Loligo sibogae), Indian white prawn (Fenneropenaeus indicus), and mud crab (Scylla serrata) by using inductively coupled plasma spectrophotometer (ICP-MS) from two renowned fish harvesting coastal area of Malaysia named as Kedah and Selangor. Among the target heavy metals, highest mean concentration of As and Fe were found in Scylla serrata (72.14±7.77 µg/g) in Kedah and Megalaspis cordyla (149.40±2.15 µg/g) in Selangor. Pearson's correlation results showed As-Fe-Cd-Cu originated from the same source. Maximum estimated daily intake (EDI) values of Scylla serrata were found 175.25 µg/g/day and 100.81 µg/g/day for child in both Kedah and Selangor areas respectively. Hazard quotient (HQ) and hazard index (HI) results revealed that local consumers of Kedah and Selangor will face high chronic risk if they consume Scylla serrata, Fenneropenaeus indicus, and Megalaspis cordyla on regular basis in their diet. Carcinogenic risk results suggested that all the studied species pose very high risk of cancer occurrences to the consumers in both areas. Therefore, it could be recommended that consumers should be aware when they are consuming these marine species since they can pose serious health risk associated with prolonged consumption.