ICAPS 2023
Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/26832
Browse
5 results
Search Results
Item Microplastic contamination in shrimps from the Negombo Lagoon- Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Lawan, P. L. M. J. H.; De Silva, D. S. M.; Amarathunga, A. A. D.; McGoran, A.; Bakir, A.; Sivyer, D. B.Microplastics (MPs) are minute pieces of plastic debris that are smaller than 5 millimeters in size. They are created through the fragmentation or degradation of more oversized plastic items such as bottles, bags, and packaging materials. Additionally, MPs can also be intentionally manufactured for certain products like microbeads in personal care products. Microplastic pollution has turned into a severe global issue affecting freshwater systems, coastal regions, and oceans. These non-biodegradable materials have a detrimental impact on marine species and ecosystems, causing disruption to their feeding, breathing, and reproduction. The intention of this study was to identify and categorize the MPs present in shrimps from the Negombo lagoon, Sri Lanka, based on the type, shape, size, and color and to characterize the polymer composition of the identified MPs. Fresh samples of two species of shrimps, Penaeus monodon (n=25) and Penaeus indicus (n=95) were collected from the ten locations where the known habitats of shrimps in the Negombo lagoon and MPs were isolated by gastrointestinal tracts and gills by alkali digestion followed by vacuum filtration. Stereomicroscopy coupled with advanced microimaging and analyzing software was used for characterizing the isolated MPs. From those samples, 415 MPs were identified and characterized. The results showed that the average number of MPs per individual was higher in P. monodon (4.72 ± 2.72) compared to P. indicus (3.13 ± 2.04). The average number of MPs per gram of gut tissue was also higher in P. monodon (8.29 ± 4.63) compared to P. indicus (5.52 ± 3.78). Identified MPs were categorized into five size groups, 1000 μm. The majority of MPs identified were under the category of >1000 μm, and six color categories were observed, with blue being the most prevalent. The study identified two main types of MPs; fibers and fragments, and the predominant form of MPs was fiber (93.0%), with the remaining being fragments. The polymer composition of most of the MPs included polystyrene, polyamide, polyester, polypropylene, and rayons, as identified by µ-FTIR and ATR-FTIR studies.Item Microplastics in selected offshore pelagic fish in Indian Ocean(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Jayarathna, N. K. D. M. P.; Walpita, C. N.; Amarathunga, A. A. D.; De Silva, D. S. M.; Sivyer, D. B.Microplastics (MPs) pollution in marine environment is an emerging threat to marine biota. Marine pelagic fish species such as tuna and tuna-like species caught during offshore fisheries in open seas, are known to be more commercially important and could be contaminated by MPs. As such, MPs could pose a risk to fish by themselves and to human health due to consumption of contaminated seafood. The present study was planned to investigate the MPs contamination of commercially important three pelagic fish species (Thunnus albacares, Katsuwonus pelamis, and Elagatis bipinnulata) caught from offshore fisheries using multiday boats from several locations of the Indian Ocean to fill the knowledge gap on MPs contamination of pelagic fish, especially in the Indian Ocean. Fish samples were collected from Beruwala, Galle, Panadura and Negombo fishery harbors in Sri Lanka, and the gastrointestinal tract (GIT) and gills were examined for possible MP contamination. A total of 40 samples belonging to three fish species were used for the study. The abundance and morphology (i.e. color, shape) of the MPs were assessed, and the polymer type of the MPs was investigated by using ATR-FTIR. Descriptive analysis was done by using IBM SPSS statistical version 26 and MS excel was used to calculate the percentages of MPs by color, shape and polymer type. There was a contamination of MPs in all three fish species. Nevertheless, 12.5% of E. bipinnulata and 21.7% of K. pelamis did not show MPs in analyzed tissues. T. albacares was found to have the greatest number of MPs (15±6 items individual-1). The morphology of the MPs found from the GIT and gills of all the three fish species were fibers (51%), followed by fragments (37%) and films (12%). In GIT, the most prominent color was blue in all the fish species. Moreover, the polymer types found belonged to three categories viz, thermoplastic elastomers (TPE), phenol formaldehyde resin (PF), and polyethylene copolymer (PE-Copolymer). Among them, the most prominent type of polymer was PF. PE-copolymer was found only in T. albacares. Therefore, continuous monitoring of marine environment and implementing stringent regulations are recommended to minimize plastic pollution in the Indian Ocean to protect both the marine ecosystem and humans.Item Microplastic contamination in selected commercial fish species in Negombo Lagoon, Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Athukorala, A.; Amarathunga, A. A. D.; De Silva, D. S. M.; Bakir, A.; McGoran, A.; Sivyer, D. B.; De Silva, C. L. C. L.; Narangoda, S. R. C.Microplastics (MPs) act as physical anthropogenic pollutants and their ability to act as contaminant vectors in biological matrices has become a serious ecosystem and human health concern. The present study, for the first time, has screened and detected MPs in the gastrointestinal tract and gill of a select group of commonly consumed fish species from Negombo lagoon, Sri Lanka. Negombo lagoon is one of the most productive ecosystems in Sri Lanka. A total of 60 fish samples were investigated for the microplastic presence, abundance, and morphological types within the guts and gills of commercial fish consisting of seven (7) species: Siganus javus (SJ:n=5), Leiognathus splendens (LS: n=8), Leiognathus blochii (LB: n=5), Mugil cephalus (MC: n=19 ), Strongylura leiura (SL: n=10), Stolephorus indicus (SI: n=10), and Caranx heberi (CH: n=3) with different feeding habits and habitats. Samples were collected between July–December 2022. Fish gut content was screened for the presence of MPs using the alkaline digestion and density gradient separation technique (NaCl hypersaline solution) and examined using a stereomicroscope and micro-Fourier transform infrared spectrometer (m-FTIR). Microplastics, ranging from 0.05 to 4.80 mm, were found in the investigated fish species. Remarkably, this study revealed that 51.67% and 32.00 % of the fish samples contained microplastic in their guts and gills respectively. A total number of 67 MP particles (size < 5 mm) were found in the excised fish guts of the seven species. The most common morphology of microplastics discovered in fish guts was fragments, which accounted for 87.5% of all MPs present. The MP content in guts differed between species. Of that Mugil cephalus recorded the greatest amount of MP ingestion, with an average MP count of 2.68±0.23 items per individual in fish gut corresponding to an average abundance of 0.22±0.26 particles/g and 0.84 ±0.46 items per individual in gills corresponding to an average abundance of 0.41±0.68 particles/g. The majority of ingested particles were fragments (40.3%), followed by fibers (34.33%), films (19.40%), microbeads (4.48%), filament (2.29%), and no pellets were observed. In terms of colour, the most abundant were blue (58.20%), followed by green (13.43%), transparent particles (8.96%), yellow (7.46%), red (5.97%), black (2.98%), white, brown, pink (1.49%) were found in low number. The majority of MPs presented were identified by m-FTIR as particles of polypropylene and polyethylene (HDPE), rayon. The results are evident in the growing threat of MPs on biological matrices and ingested MPs in edible fish species present in the Negombo lagoon.Item Assessment of litter and microplastic pollution in the water and sediment of Hirikatuoya stream, within the Walawe River basin, Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Lahiru, A. A. S.; Amarathunga, A. A. D.; Malavipathirana, S.; De Silva, D. S. M.; Sivyer, D. B.Rapid urbanization and mismanagement have led to a surge in plastic pollution in crucial aquatic ecosystems globally therefore accumulation of debris in aquatic ecosystems is rapidly increasing and they are becoming ultimate sinks for the contaminants. This results in a long-term and widespread threat causing a great challenge for remediation. Poor disposal practices and littering behavior of communities have resulted in considerable quantities of litter in river banks and streams affecting their aesthetic appeal and living beings. This study was conducted to understand the status of litter and microplastic contamination at selected locations in Hirikatuoya stream, a remote stream outside the urban environment in the Rathnapura district, Sri Lanka. The percentage of plastic in litter and the percentages of microplastic particles (based on colour and morphotypes) in water and sediments were estimated, and the corresponding polymer types were also identified. Three samples of water were collected from each of the nine locations along the stream from September to October 2022. In the sampling process, the samples were filtered through a 150 μm mesh. Sediment samples were collected from the shoreline of the stream at each location using a stainless-steel scoop covering 30 cm2 of surface area and 2-3 cm depth. Lowdensity particles in the samples were separated by density separation and organic matter in the sample was removed by digestion. Whatman GF/C glass microfiber filter papers of a pore size of 1.2 μm were used for sample filtration. Microscopic imaging was done using a staining method. The ATR-FTIR analysis was performed to identify the polymer type of plastic particle in water samples. The most frequently observed colour for microplastic particles in water and sediments were white (26.87%) and colourless (40.20%), respectively. Based on morphotype, fragments were more abundant in both water (49.62%) and in sediments (59.79%) compared to other morphotypes. The highest microplastic abundance in water (69±22, 60±29, 61±26 items 100 m- 3) and highest abundance of microplastics in sediment (15±5.92 items/kg (top), 7±3.28 items/kg (bottom)) were observed in more human and tourist activity locations. According to the ATRFTIR analysis, polypropylene was the most abundant polymer type in plastic litter (25%). In water polypropylene was the most dominant microplastics (38.10%), followed by low-density polyethylene (14.29%) and polyethylene terephthalate (9.52%). Polypropylene was the dominant microplastics in sediments (32.2%), followed by thermoplastic vulcanizates (22.5%), highdensity polyethylene (19.3%). Accordingly, it can be concluded that the Hirikatuoya stream, which is in a remote area, is contaminated with microplastics. There are potential environmental and health risks to the aquatic biota in the stream and the neighboring communities. Further investigations are required to understand the effect on aquatic animals.Item Abundance and microplastic characterization found in the mud crab Scylla serrata inhabiting Negombo Lagoon, Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Dias, B. C. G.; Amarathunga, A. A. D.; De Silva, D. S. M.; Sivyer, D. B.; Maddumage, M. D. S. R.Microplastics (MPs) are tiny plastic particles less than 5 mm in size. The danger imposed by MPs continues to rise in the world due to an increase in anthropological pollutants in the environment. The tremendous socioeconomic value and biodiversity of the lagoon have been threatened by a significant accumulation of plastics, particularly MPs. MPs have many negative impacts on the fauna. Herein, the high adsorption capability of MPs increases the toxicity of contaminants as well as oxidative stress that may lead to damaging cell membranes of fauna. Here, we report the investigation on the abundance of MPs in the digestive tract and gills of the mud crab species Scylla serrata, which is a prominent edible food source of humans. We collected fifty two (N = 52) individuals of mud crabs from three crab trapping sites in the Negombo Lagoon, Sri Lanka during November 2022 to March 2023. The gills and digestive tract of the crabs were extracted and digested in KOH, and subsequently the putative MPs were separated and imaged using a stereomicroscope (VWR VisiScope 360) for characterization. In the analysis, a total of 455 MP particles were detected in the crabs, out of which, 187 (41.10%) were in the gills and 268 (58.90%) were in the digestive tracts. The average MP abundance in the gills was 0.70 ± 0.52 items per gram, while that in the digestive tracts was 0.71 ± 0.52 items per gram. The most abundant shapes of MP particles were fibers in the gills (54.01%) and in the digestive tracts (85.07%) followed by fragments and films. Further, the prevailing colours of the MPs were blue, transparent, red, black, and purple. Herein, the digestive tract had the highest concentration of MPs in blue (47.38%), whereas the majority of the MPs found in the gills were transparent (51.8%). The range of MP sizes in the crabs was also determined. The most frequent size range in the gills and digestive tracts were 0.002-0.25 mm (39.5%), and 1.0-5.0 mm (48.8%) respectively. Despite the fact that the current study offered details on the presence of MPs in the gills and digestive tract of the mud crab species Scylla serrata inhabits in the Negombo Lagoon, it also serves as a benchmark for the quick detection of MPs in mud crabs in the lagoons of Sri Lanka.