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Microplastics in Sumba waters, East Nusa Tenggara

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  • The Indonesian National Research and Innovation Agency
  • National Research and Innovation Agency - Indonesia

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The accumulation of plastic debris in the oceans has been widely recognized as a threat to marine environment. A recent study estimated that Indonesia is one of the biggest sources of plastic wastes in the ocean, but directly-measured abundance data from the seawater in Indonesia is lacking. We documented the abundance and distribution of microplastics (size <5mm) in sub-surface seawaters of Sumba, a pristine region in Indonesia. Water samples were collected from 5 m, 50 m, 100 m, 300 m depth and near the sea bottom. Samples were examined for microplastics using flotation and filtration methods. We found microplastic in all sampling locations, consisting of fibers (45.45%), granules (36.36%) and other plastic form (18.18%). Most of microplastic particles were found at water depths less than 100 m (81.82%), which was the thermocline area. Our finding corroborates the believe that plastics has widely invaded marine environment in different parts of the seas and oceans, including pristine, remote, and unknown areas.
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Microplastics in Sumba waters, East Nusa Tenggara
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IOP Conf. Series: Earth and Environmental Science 162 (2018) 012023 doi :10.1088/1755-1315/162/1/012023
Microplastics in Sumba waters, East Nusa Tenggara
M R Cordova and U E Hernawan
Research Center for Oceanography, Indonesian Institute of Science (LIPI). JL. Pasir
Putih 1, Ancol, Jakarta Utara, Jakarta, 14430, Indonesia
E-mail: muhammad.reza.cordova@lipi.go.id
Abstract. The accumulation of plastic debris in the oceans has been widely recognized as a
threat to marine environment. A recent study estimated that Indonesia is one of the biggest
sources of plastic wastes in the ocean, but directly-measured abundance data from the seawater
in Indonesia is lacking. We documented the abundance and distribution of microplastics (size
<5mm) in sub-surface seawaters of Sumba, a pristine region in Indonesia. Water samples were
collected from 5 m, 50 m, 100 m, 300 m depth and near the sea bottom. Samples were examined
for microplastics using flotation and filtration methods. We found microplastic in all sampling
locations, consisting of fibers (45.45%), granules (36.36%) and other plastic form (18.18%).
Most of microplastic particles were found at water depths less than 100 m (81.82%), which was
the thermocline area. Our finding corroborates the believe that plastics has widely invaded
marine environment in different parts of the seas and oceans, including pristine, remote, and
unknown areas.
1. Introduction
Plastics are a successful story with regard to their characteristics that make them suitable for a wide
variety of products [1]. By 2014 the total plastic production reached 311 million tons [2]. High
consumption rate but low recovery rates has driven plastics to be a potential threat to the environment.
[3] reported that most of plastic packaging is not recovered, of which 40% goes landfilled and 32% leaks
to the environment including marine ecosystem. Plastic pieces that ended up in the environment remain
still with very slow degradation (up to 100 years). Recent studies estimated that plastic debris in the
ocean are between 7,000 250,000 metric tons [4,5]; land based input to the oceans are between 4.8 -
12.7 metric tons; and Indonesia was listed as one of the top sources of land based input [6]. This
estimation, however, lacks real abundance data in the ocean since it used mathematical model based on
solid waste production, population density and economic status of the countries.
Plastic pollution was initially seen as an aesthetic problem [7,8], however recent studies have shown
that marine animals can be negatively affected by the presence of plastics. Threats posed by plastics
with large size are obvious, clear environmental risks by physical impairment after swallowing,
entanglement [9]. [10] stated that from the 1960s to 1990s, physical impairment caused by plastics had
increased almost three times (267 to 693 species). Furthermore, [9] reported that all seabird species
(395 species) contained plastics in their digestive systems.
Plastic waste can be degraded by UV thermal oxidation or mechanic processes up to the microscopic
size [11,12]. Microplastics (<5mm) are formed by the physical, chemical and biological fragmentation
of larger items of plastics. Besides commonly-used plastics, microplastic may originate from cosmetic
or fabric, in the form of microbeads [13,14]. The impact of microplastics in the marine environment are
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not clearly known. Studies in the last decade have indicated potential environmental risks from
microplastics, but real consequences are mostly unknown. Microplastics accumulation in
gastrointestinal on marine organism has been reported [1519], but the impact of the accumulation to
the organisms are not known. Microplastics could enter the food web by organism ingestion [20], could
interference digestive tract function [17], and may act as a carrier for organic material and heavy metals
[2123].
Sumba, located in East Nusa Tenggara, Indonesia, is a pristine region in the outlet of Indonesian
Through Flow (ITF) connecting the Pacific Ocean and the Indian Ocean. It is in the southern part of the
Wallacea transition zone, where Indo-Malaya and Australasian biogeographic characteristics meet. It
has unique marine ecosystems and high biodiversity. This area is an important migration corridor to
many marine megafaunas and pelagic fishes. Here, we documented the abundance and distribution of
microplastics (size <5mm) in sub-surface seawaters of Sumba.
2. Introduction
2.1. Study area
Sumba is located in East Nusa Tenggara, eastern Indonesia (Figure 1). Sumba waters area is believed to
have high marine life, but minimal scientific information. From the perspective of oceanography, this
area is also believed to be unique because of the interaction between Indonesian Through Flow
(ITF/Arlindo). The presence of four water masses on the western side, north and south of Sumba Island
(Northern Pacific Subtropical Water-NPSW, North Pacific Intermediate Water-NPIW, Northern Indian
Subtropical Water-NISW and Northern Indian Intermediate Water-NIIW), proves that this area is an
outlet of ITF [2426]. A front near the western tip of Sumba Island potentially trigger an eddy and might
be influenced by the South Java Current (SJC) [2426]. This current is believed to trigger upwelling
which is important for fishery resources. In addition, oceanographic process also believed to be
important in Sumba region is mixing, that is the mixing of water masses that can occur due to tidal
currents, bathymetry, and internal waves.
2.2. Sample collection
Sampling was conducted during the 9th Ekspedisi Widya Nusantara (EWIN IX) in August 2016 using
RV Baruna Jaya VIII. Sampling sites are shown in Figure 1. Water samples (10 liters per depth per site)
were collected using Rosette Water Sampler at 5 m, 50 m, 100 m, 300 m and near the sea bottom, then
were filtered using a sterile Whatman® cellulose nitrate filter papers (diameter 47 mm; pore size
0.45µm). To accelerate filtration process, we used Gast vacuum DOA-P504-BN. All samples in the
filter papers were stored at 4±2 °C before analysis in sterile Petri dish and covered with ParaFilm®
sealing film. To prevent samples from being contaminated, we wore laboratory latex gloves and
eyeglasses for filtering, sorting and counting. All sterile glassware were used and filters were stored in
Petri dishes, sealed with Para Film.
2.3. Sample analysis
Microscope Leica M205C was used to examine microplastics particles on the filters. We were using the
following characteristics [17,27,28] to identify microplastics, namely (1) particle size ≤ 5mm, (2)
homogeneous colour, not shiny or sparkling and no cellular or organic structure, (3) fiber particles are
unbranched and not segmented. The microplastics identified were counted and measured. The types of
microplastic then were classified as fibers, granule, fragment, and foam; and were categorized to the
size of <300µm; 300-500µm; 500-1000µm; >1000µm. We analyzed microplastics with sizes more than
250µm using Fourier Transform Infrared (FT-IR). FT-IR can be used to analyze microplastics samples
directly [29]. Polymer analysis was done using Nicolet™ iS5 FT-IR Spectrometer, equipped with a
laminated diamond crystal Thermo Scientific™ iD5 attenuated total reflectance (ATR) accessory, and
corrected using Omnictm Software. The instrument was operated based on [30] at a range of 600 and
3800 cm-1, a resolution 8 cm and at a rate of 16 scans per analysis, in single reflection mode. Before
we analyzed using FT-IR, all potentially plastic particles were rinsed with ethanol 96%. To prevent
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samples from airborne contamination, we analyzed all particles based on a report by [31]. Afterwards,
we did not quantify the fiber particle of the same polymer type as the lab clothes we have worn.
Microplastics concentration are presented as n/m3 unit (Table 1) to compare with other research result,
simple statistical tests were performed on the data collected using Microsoft Excel are presented mean
values ± standard deviations (SDs).
Figure 1. Sampling sites and average abundance of microplastics particles in five different depth (5 m,
50 m, 100 m, 300 m depth and near the sea bottom)
3. Results and discussion
3.1. Study area
Plastic particles were found in all sampling location (10 sampling locations). Average microplastics
concentration per station in five different depth were 44 ± 24.59 n/m3. The highest concentration of
microplastics was observed in Sumba Strait (St-8 and St-10). At 5m depth, microplastics particles were
found in all sampling locations (Figure 2). However, microplastics was not observed at 100m depth.
This might be related to the presence of thermocline zone, ranging from 53m to 144m depth.
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Figure 2. Average of microplastics abundance (n particles/m3) in all station at
five different depth in Sumba Sea
Microplastics abundance at 5m depth was nearly similar with that of the coastal area in Yangtze
estuary China [32,33]. The abundance in this area was higher than that of other open oceans, for example
North East Atlantic Ocean (2.46 n/m3; [34]), East China Sea (0-1.44 n/m3; [33]), and North West
Mediterranean (0.116 n/m3; [35]. The wide variety of microplastic abundance in different oceans might
be related with the fact that microplastics tend to be heterogeneously distributed in a water mass [36].
Because Sumba region is one of the ITF outlets [2426], characterized by four water masses (NPSW,
NPIW, NISW, NIIW), we believe that microplastics observed in Sumba might not only come from
anthropogenic activities around [28] Sumba, but also from other parts of the oceans in the Pacific.
Table 1. Microplastics occurrence, characteristic and polymer composition
Size
Form
Percentage
(%)
Percentage
(%)
Fibers
Granule
Other
PE
PS
PA
PP
<300µm
1
1
0
9.09
1
0
0
0
4.55
300-500µm
3
2
4
40.91
4
2
1
1
36.36
500-1000µm
4
5
0
40.91
5
0
0
4
40.91
>1000µm
2
0
0
9.09
4
0
0
0
18.18
Percentage (%)
45.45
36.36
18.18
63.64
9.09
4.55
22.73
PE- Polyethylene; PS- Polystyrene; PA- Polyamide; PP- Polypropylene
3.2. Microplastics occurrence, characteristic and polymer composition
We classified microplastics from Sumba into four size categories: <300µm, 300-500µm, 500-1000µm,
and >1000µm; and into three forms: fibers, granule, and other type (fragment, foam) (Table 1). In all
sampling stations, microplastic size ranges from 280µm to 1120µm. Most of identified microplastics
(81.82%) were 300-1000µm in size. Fibers were the most abundant form (45.45%), followed by granule
(36.36%) and other type (18.18%). We identified four dominated categories of plastic polymers:
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Polyethylene (PE), Polystyrene (PS), Polyamide (PA) and Polypropylene (PP). PE was the most
common dominated polymer type, followed by PP, PS, and PA (Table 2).
Figure 3. Example of comparison of the spectrum of polypropylene polymer standard from Thermo-
scientific (red) and a spectrum obtained from the measurement of a dominated polypropylene fragment
particle found in Sumba waters (blue) by ATR-based FTIR spectroscopy
Figure 3 shows examples of the polymers found, which dominated with Polypropylene (PP). From
fragment particle sample, prominent presence peak at wavenumber 2950 cm-1, 2916 cm-1, 2837 cm-1 and
2868 cm-1. Similar observation by [37] for PP samples indicated peak at 2951 cm-1, 2911 cm-1 and 2844
cm-1 indicating an asymmetrical type of vibration (ⱱa-CH2) [38]. Those were similar displayed vibration
bands of polymer standard at 2950 cm−1, 2917 cm-1, 2869 cm-1 and 2837 cm-1. In this study, fragment
particle found in Sumba waters and polypropylene polymer standard (Figure 3) showed an absorption
band at 1375 cm-1 and at 1454 cm-1. Spectrum of PP showed symmetrical deformation vibrations (δs–
CH3) at 1372 cm−1 and asymmetrical deformation vibrations (δa-CH3) at 1458 cm−1[37,38].
Size of microplastics could determine the potential impact to the organisms [28]. Smaller size
increase the possibility of microplastics ingested by the organisms [33,39]. This situation may pose
potential negative impacts to various marine megafauna and important pelagic fishes. Microplastics with
size <1000 µm frequently founded on marine organism digestive tract [16,18,19,40], suggesting that
marine organisms likely mistake microplastics as their food [41]. Microplastics could disrupt digestive
tract function [17] and could also act as a vector for organic and heavy metal pollutants [2123,42,43].
The most common form was fiber microplastics, similar to the findings by [28,33,44,45]. Fibrous plastic
particles in Sumba might derive from fishing nets and rope materials; granule comes from hard plastics
and granulated cleaner [45]. Based on FTIR analysis, most polymers identified were dominated
polyethylene, followed by dominated polypropylene and dominated polystyrene. The primary use of
polyethylene is packaging materials, e.g. food and beverage containers, geomembrane plastic bags and
film. Polypropylene is widely used in food and beverage containers, clothing industry, ropes, and re-
usable containers [4648]. Surprisingly, polyamide fiber was also found in Sumba. This fiber might
-0,005
0,000
0,005
0,010
0,015
0,020
0,025
0,030
0,035
0,040
0,045
0,050
Absorbance
500 100 0 150 0 2000 250 0 300 0 3500 40 00 Wav enu mbers ( cm-1 )
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derived from fishing nets and rope material [49,50]. Despite the fact that plastics are newly developed
materials (early nineteen centuries made), our finding, that microplastics was found in seawater of
Sumba at all surveyed depth, indicated that plastic has invaded marine areas, including pristine areas. It
confirms the common believe that plastic waste has spread widely to different parts of the seas and
oceans, including remote and unknown areas [51].
4. Conclusion
Our study reports that microplastics were found in all sampling locations, in the form of fibers (45.45%),
granules (36.36%) and other form (18.18%). Most of the microplastic particles (81.82%) were found at
water depths less than 100m, which were thermocline area. However, no microplastics was observed at
100m depth. Most of identified microplastics (81.82%) were in 300-1000µm in size. Dominated plastics
polymers identified were polyethylene, followed by polypropylene, polystyrene, and polyamide. Further
studies are planned to examine microplastic distribution in the region where ITF presence and to
investigate the potential impact of microplastics in that area.
Acknowledgement
This study was part of Ekspedisi Widya Nusantara IX (EWIN-IX) funded by DIPA LIPI from the
Government of Indonesia. We would like to thank the support from all the crews of RV. Baruna Jaya
VIII during the EWIN-IX cruise. We also thank to Mr. Sumijo Hadi Riyono for the sample collection.
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... Microplastics in open seas act like passive tracers and are transported in water according to water and wave flows. Apart from water flow, the movement of wind could affect the movement of microplastics as well [27]. This could explain why point 3 has the highest microplastic abundance. ...
... This is because water quality parameters and microplastic abundance are complex parameters and can be affected by various factors. For example, microplastic abundance can be affected by water flows, wastewater containing plastics and human activities [27,47]. The low correlations and interconnections between variables show that these three parameters must be analysed individually. ...
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Microplastic’s existence has gained much attention due to its toxicity and harmful effects on marine life. One of the microplastic behaviours in the environment is to absorb hydrophobic pollutants. This behaviour might increase the toxicity of microplastics, affect the concentration of contaminants, and harm the environment. Kenjeran coastal area is a hotspot for human activities in Surabaya City, such as tourist, military training, and fishing activities. Therefore, the Kenjeran coastal area has a high potential to be polluted by plastics and microplastics. This study aimed to identify the abundance and polymer types of microplastics, as well as their correlations with chemical oxygen demand (COD) and total suspended solids (TSS) concentrations in the seawater of the Kenjeran coastal area. Sampling was conducted at three different points in March and April 2024. The average abundance of microplastics obtained was 63-102 particles/L. Meanwhile, the polymer types obtained were polyethylene, polystyrene, ethylene vinyl acetate, and polycarbonate. The correlation test results show that microplastic abundances do not have a significant correlation with COD and TSS concentration in seawater. This study can be used for further research in emerging pollutants and decision-making processes regarding plastic management from the source to the sea.
... Microplastics were detected on the sea surface as fragments, fiber, and films in the Savu Sea, East Tenggara (Hiwari et al., 2019). A similar study has found fibers (45.45%), granules (36.36%), and other plastic forms (18.18%) in the water column in Sumba waters (Cordova and Hernawan, 2018). While microplastics have been detected in the surface waters in the eastern Indonesian region, less is known about their presence in deeper layers and on the seabed, especially in strategic locations such as the Flores Sea, which is directly influenced by the Indonesian Throughflow (ITF). ...
... Our findings are consistent with the previous studies globally, which found that fiber/filament compositions consist of PET, PE, PP, PVA, and PE (Browne et al., 2011;Wang et al., 2022). Other studies in the waters of Sumba found a similar composition to the findings in this research (Cordova and Hernawan, 2018). It has further been reported that PET is used in clothes and the components of ropes, nets, and fishing lines (Wang et al., 2020). ...
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Despite growing global concerns, there has been limited research on the characterization and distribution of microplastics in the Indonesian Throughflow (ITF) pathways, such as the Flores Sea. The Flores Sea is a component of the Indian–Pacific Current, a significant ocean current system that links the Pacific and Indian oceans and has the capacity to carry pollution over large marine ecosystems, making this research extremely important. Understanding the microplastic pollution in this area informs local environmental management. It provides insights into how these currents may distribute microplastics (MPs) across regional and global scales, impacting marine life and human health far beyond the immediate area. To respond to these concerns, this research aims to determine the characterization and distribution of MPs at six research sites in the Flores Sea that are precisely located within the ITF. This work exhibits an extensive dataset focusing on the occurrence, attributes, and dispersion of microplastics in the Flores Sea. The water sampling was carried out during a Jala Citra 3 by the Indonesian Navy from April to May 2023. Sea surface water samples were collected using a Neuston net, while sediment samples were taken from three stations at the shallowest depth using the Ekman Grab sampler. Additionally, abundance, size, shape, and color analyses were conducted using a light microscope, and microplastic types were identified through Raman spectroscopy. The results indicated that the Flores Sea waters and sediment are polluted with microplastics, with relative abundances ranging from 0.75 ± 0.49 to 2.13 ± 0.25 items/l samples. The most dominant shapes identified were filament (77.45%) and fragment (13.40%), with sizes varying between surface water 4.70 to 3799.25 μm and seabed from 67.20 mm to 2176.87 mm, while black (30.07%) and blue (24.51%) were reported as the common MPs colors. The identified polymers include PET and PE. This study confirms visual evidence of microplastics in the open waters of eastern Indonesia. While it may not fully capture the wide range of temporal variations, it establishes initial microplastic presence and dispersion levels. Given that the ITF influences both the Pacific and Indian Oceans, this research contributes to the global understanding of microplastic distribution across ocean basins, underscoring the need for coordinated international efforts to address marine pollution.
... MP size can be used as an indicator of the potential impact on organisms in aquatic environments. Its smaller size allows it to be digested by organisms (Cordova & Hernawan 2018). MP with a size of <100 µm cannot be seen directly with the eye so that MP can easily enter the body and endanger human health (Sathish et al 2020). ...
... MP with sizes <1000 µm are commonly found in the digestive tract of marine organisms. Marine organisms cannot differentiate between food and MP (Cordova & Hernawan 2018). MP size <500 µm require a long time to experience displacement, especially in waters that are not affected by tides and waves, such as rivers and lakes. ...
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The use of plastic materials has led to the penetration of microplastic (MP) into the aquatic environment. MP is plastic that is less than 5 mm in size. They have received significant attention in recent years due to their impact on humans and organisms as they absorb organic and pathogenic contaminants from the surrounding media. This study aims to analyze MP abundance, shape, color, size, and polymer characteristics at five water sampling stations in Maninjau Lake. Water samples were extracted to obtain MP, then analyzed using a microscope and ATR-FTIR spectroscopy. MP abundance in Maninjau Lake water samples ranged from 180 to 335 L-1 particles. The most dominant shape, color, and sizes found in the waters were fragments (12.5%), black (68.37%), and sizes of 101-300 µm (49%). Based on the results of the characterization and interpretation of functional groups in the FTIR spectrum, several types of polymers were found, including polyamide (PA), polypropylene (PP), and polyester (PES).
... The application of ZnCl 2 facilitated microplastic recovery rates of 96-100% for bigger particles and 96% for smaller particles, frequently employed for microplastic separation in sediment samples [32,33]. The supernatant was extracted using a glass pipette and subsequently filtered using Whatman filter paper (diameter: 47 mm, pore size: 0.45 µm) with a vacuum pump (Vacuubrand ME2C) [17,34]. The particles on the filter paper were transferred to a 250 mL beaker, where purification was conducted by adding 20 mL of a 30% hydrogen peroxide solution (H 2 O 2 ) and 20 mL of ferrous sulphate (Fe(II)SO 4 ) to enhance the reaction rate (Merck Millipore, EMSURE® ACS, ISO, Reag. ...
... b, Proportions of buoyant and dense microplastics in nearshore and offshore waters. Data were compiled from 18 peer-reviewed papers on water-column microplastics that provided polymer compositions 3,4,6,15,16,25,33,60,67,68,72,83,126,127,[129][130][131][132] . Polymers with densities lower than natural seawater (ρ = 1.025 g cm −3 ) are defined as buoyant polymers whereas dense polymers have a density greater than natural seawater. ...
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Marine plastic pollution is a global issue, with microplastics (1 µm–5 mm) dominating the measured plastic count1,2. Although microplastics can be found throughout the oceanic water column3,4, most studies collect microplastics from surface waters (less than about 50-cm depth) using net tows⁵. Consequently, our understanding of the microplastics distribution across ocean depths is more limited. Here we synthesize depth-profile data from 1,885 stations collected between 2014 and 2024 to provide insights into the distribution and potential transport mechanisms of subsurface (below about 50-cm depth, which is not usually sampled by traditional practices3,6) microplastics throughout the oceanic water column. We find that the abundances of microplastics range from 10⁻⁴ to 10⁴ particles per cubic metre. Microplastic size affects their distribution; the abundance of small microplastics (1 µm to 100 µm) decreases gradually with depth, indicating a more even distribution and longer lifespan in the water column compared with larger microplastics (100 µm to 5,000 µm) that tend to concentrate at the stratified layers. Mid-gyre accumulation zones extend into the subsurface ocean but are concentrated in the top 100 m and predominantly consist of larger microplastics. Our analysis suggests that microplastics constitute a measurable fraction of the total particulate organic carbon, increasing from 0.1% at 30 m to 5% at 2,000 m. Although our study establishes a global benchmark, our findings underscore that the lack of standardization creates substantial uncertainties, making it challenging to advance our comprehension of the distribution of microplastics and its impact on the oceanic environment.
... For instance, there has been notably less survey activity in offshore regions, including the South China Sea, than in coastal and riverine areas. Although monitoring efforts in the open ocean have increased (e.g., in the Indonesian Throughflow region; Cordova et al., 2024a;Cordova and Hernawan, 2018;Yuan et al., 2023), the amount of monitoring is still low. This discrepancy is likely due to the limited opportunities for offshore surveys, which in turn stem primarily from the scarcity of large research vessels. ...
... Studies on microplastic contamination in various ecosystems, such as estuaries (Ambeng et al., 2022), coral reefs (Cordova and Hernawan, 2018;Ilham, et al., 2023a), neritic zone (Yona et al., 2023), pelagic zones (Cordova et al., 2019), and deep seas (Cordova and Wahyudi, 2016), have b een conducted in various regions of Indonesia, including South Sulawesi. Ilham et al., (2023a) reported that all zones in Makassar and Pangkep waters, which are included in the Spermonde Archipelago, were contaminated with micro debris. ...
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Highlight Research 1. Microplastics were counted and identified based on their shape, size, and color 2. The particles were clarified using FTIR and confirmed to be microplastics based on the type of polymer. 3. The tissue destruction method is more effective with heating treatment. 4. Methods to prevent contamination are implemented so that the research results are guaranteed to be accurate. Abstract Microplastics can be ingested by marine organisms, including fish. Although it has been widely reported, further information regarding microplastic contamination in commercial fish is still needed. This study aimed to analyze the presence and concentration of microplastics in the digestive tract of the mackerel R. kanaguarta and red snapper L. gibbus and to identify the shape, size, color, and type of microplastic polymer. Digestion of the organic materials was performed using a 10% KOH solution, which was then filtered using a vacuum filtration system. The particles were observed using an Olympus microscope and clarified using FTIR. The results of the research showed that R. kanaguarta and L. gibbus landed at the Beba Fish Landing Base (PPI Beba) Takalar were contaminated with microplastics with a microplastic concentration in R. kanaguarta 0.21 ± 0.06 particles/g and L. gibbus 0.11 ± 0.04 particles/g. The microplastics found were fiber and fragment of varying colors, such as black, white, red, and yellow. The size of microplastics was dominant in the size class < 2 mm. The FTIR analysis confirmed the presence of polypropylene (PP), Ethylene/Propylene Copolymer, Nylon, Polyethylene terephthalate (PET), and polyester (PES). This study showed that both commercial fish species were contaminated with microplastics. These findings suggest that microplastics are widespread and contaminate commercial fish caught from Takalar waters. Further research is still needed on other seafood from this region, and analysis of polymer types such as FTIR is important to carry out as one of the standard methods in microplastic research.
... It is important to mention that depending on hydrodynamic and geographic conditions, and the depth of marine waters, samples can be divided into (i) bulkwater sampling and (ii) net sampling (Liu et al., 2020a, b). Bulk-water sampling is a type of sampling that aims to collect a defined volume of water at specific water layers for a limited duration and employs sample devices such as the Rosette sampler system (CTD sampler) (Botterell et al., 2022;Cordova & Hernawan, 2018;Dai et al., 2018), the plexiglass water sampler (Ding et al., 2019), and the lander system (Liu et al., 2019). However, contemporary studies generally opt for net sampling, which primarily includes manta nets (Karlsson et al., 2020;Pan et al., 2021;Tošić et al., 2020), followed by neuston (Athapaththu et al., 2020;Sagawa et al., 2018), and plankton nets (Forero-López et al., 2021;Tsang et al., 2017). ...
Chapter
In recent years, microplastics (MPs) have emerged as a significant concern due to their widespread presence, non-biodegradable nature, and ability to adsorb, leach, and transport other pollutants in the marine environment. In addition, they pose a potential risk to human health through the consumption of seafood. MPs can enter the oceans by different pathways and can be transported over long trajectories, disseminating various types of pathogens, and organic and inorganic contaminants, in marine ecosystems. Once introduced into aquatic environments, MPs undergo various biotic and abiotic processes, including weathering and biodegradation. These processes alter their physicochemical characteristics, thereby influencing their toxicological impact on organisms. This chapter discusses how these plastic particles enter marine ecosystems, their dynamics once inside, and the degradation processes to which they are exposed, as well as advances in MPs sampling and analyzing techniques.
... Despite the differences between sampling, processing, and analytical techniques for microplastic identification, the mean microplastic concentration in sub-surface waters along the ITF pathway in this study was relatively higher than that observed in the subsurface deep-sea waters across the world (the comparison of microplastic concentration between this study with other study is presented in the Supplementary material, Table S4). The microplastic content in the water column of the ITF pathway is higher than in Sumba waters (Cordova and Hernawan, 2018), North East Pacific Ocean (Desforges et al., 2014), Indian Ocean (Lusher et al., 2014), Atlantic Ocean (Courtene-Jones et al., 2017;Enders et al., 2015;Kanhai et al., 2017;Lusher et al., 2014Lusher et al., , 2015, Artic Ocean (Kanhai et al., 2018), North Pole/Central (Ross et al., 2021), Beaufort Sea (Ross et al., 2021), Eurasian Arctic (Yakushev et al., 2021) and Antarctic seawater . Whereas, the average microplastic abundance in the main of ITF was lower than that reported in the Mariana Trench (Peng et al., 2018). ...
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Microplastics in aquatic ecosystems and especially in the marine environment represent a pollution of increasing scientific and societal concern, thus, recently a substantial number of studies on microplastics were published. Although first steps towards a standardization of methodologies used for the detection and identification of microplastics in environmental samples are made, the comparability of data on microplastics is currently hampered by a huge variety of different methodologies, which result in the generation of data of extremely different quality and resolution. This chapter reviews the methodology presently used for assessing the concentration of microplastics in the marine environment with a focus on the most convenient techniques and approaches. After an overview of non-selective sampling approaches, sample processing and treatment in the laboratory, the reader is introduced to the currently applied techniques for the identification and quantification of microplastics. The subsequent case study on microplastics in sediment samples from the North Sea measured with focal plane array (FPA)-based micro-Fourier transform infrared (micro-FTIR) spectroscopy shows that only 1.4 % of the particles visually resembling microplastics were of synthetic polymer origin. This finding emphasizes the importance of verifying the synthetic polymer origin of potential microplastics. Thus, a burning issue concerning current microplastic research is the generation of standards that allow for the assessment of reliable data on concentrations of microscopic plastic particles and the involved polymers with analytical laboratory techniques such as micro-FTIR or micro-Raman spectroscopy. © 2015, Springer International Publishing. All Rights Reserved.
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There have been numerous anthropogenic-driven changes to our planet in the last half-century. One of the most evident changes is the ubiquity and abundance of litter in the marine environment. The EU Marine Strategy Framework Directive (MSFD, 2008/56/EC) establishes a framework within which EU Member States shall take action to achieve or maintain good environmental status (GES) of their marine waters by 2020. GES is based on 11 qualitative descriptors as listed in Annex I of the MSFD. Descriptor 10 (D 10) concerns marine litter. As a follow-up to the related Commission Decision on criteria and methodological standards (2010/477/EU) in which 56 indicators for the achievement of GES are proposed, the EC Directorate-General for the Environment, on the request of the European Marine Directors, established a Technical Subgroup on Marine Litter (TSG ML) under the Working Group on GES. The role of TSG ML is to support Member States through providing scientific and technical background for the implementation of MSFD requirements with regard to D 10. Started in 2011, TSG ML provides technical recommendations for the implementation of the MSFD requirements for marine litter. It summarizes the available information on monitoring approaches and considers how GES and environmental targets could be defined with the aim of preventing further inputs of litter to, and reducing its total amount in, the marine environment. It also identifies research needs, priorities and strategies in support of the implementation of D 10. The work of TSG ML also focuses on the specification of monitoring methods through the development of monitoring protocols for litter in the different marine compartments, and for microplastics and litter in biota. Further consideration is being given to monitoring strategies in general and associated costs. Other priorities include the identification of sources of marine litter and a better understanding of the harm caused by marine litter.
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A two-step method was developed to extract microplastics from sediments. First, 1 kg sediments was pre-extracted using the air-induced overflow (AIO) method, based on fluidisation in a sodium chloride (NaCl) solution. The original sediment mass was reduced by up to 80%. As a consequence, it was possible to reduce the volume of sodium iodide (NaI) solution used for the subsequent flotation step. Recoveries of the whole procedure for polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polystyrene and polyurethane with sizes of approximately 1 mm were between 91 and 99%. After being stored for one week in a 35% H 2 O 2 solution, 92% of selected biogenic material had dissolved completely or had lost its colour, whereas the tested polymers were resistant. Microplastics were extracted from three sediment samples collected from the North Sea island Norderney. Using pyrolysis gas chromatography/mass spectrometry, these microplastics were identified as PP, PVC and PET.
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Qualitative analysis of the structures of the polymers composing floating plastic debris was performed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and the aging of the debris was assessed by measuring carbonyl group formation on the particle surfaces. Plastic material made up > 75% of the 2313 items collected during a three-year survey. The size, shape and color of the microplastic were correlated with the polymer structure. The most abundant plastic materials were polypropylene (68%) and low-density polyethylene (11%), and the predominant colors of the plastics were white, blue and green. Cilacap Bay, Indonesia, was contaminated with microplastic at a concentration of 2.5 mg·m³. The carbonyl index demonstrated that most of the floating microplastic was only slightly degraded. This study highlights the need to raise environmental awareness through citizen science education and adopting good environmental practices.
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Microplastics pollution has been documented in the global environment, including at sea, in freshwater and in atmospheric fallout. Ingestion of microplastics by multiple kinds of organisms has been reported and has received increasing attention, because microplastics not only act as a source of toxic chemicals but also a sink for toxic chemicals. To better understand the great concerns about microplastics and associated toxic chemicals potential exposed to the organisms ingesting the debris, we should know more about the occurrence, fate, and risks of microplastics in the environment. What we should do depends on this better understanding. Integr Environ Assess Manag 2017;13:476–482. © 2017 SETAC Key Points Microplastics were found in the marine environment, the freshwater environment, and atmospheric fallout. Microplastics not only act as a source of toxic chemicals but also a sink for toxic chemicals. Fate of microplastics might associate with sedimentation, shore deposition, nanofragmentation, and ingestion. Further research is needed, and what we should do depends on better understanding.
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The permanent presence of microplastics in the marine environment is considered a global threat to several marine animals. Heavy metals and microplastics are typically included in two different classes of pollutants but the interaction between these two stressors is poorly understood. During 14 days of experimental manipulation, we examined the adsorption of two heavy metals, copper (Cu) and zinc (Zn), leached from an antifouling paint to virgin polystyrene (PS) beads and aged polyvinyl chloride (PVC) fragments in seawater. We demonstrated that heavy metals were released from the antifouling paint to the water and both microplastic types adsorbed the two heavy metals. This adsorption kinetics was described using partition coefficients and mathematical models. Partition coefficients between pellets and water ranged between 650 and 850 for Cu on PS and PVC, respectively. The adsorption of Cu was significantly greater in PVC fragments than in PS, probably due to higher surface area and polarity of PVC. Concentrations of Cu and Zn increased significantly on PVC and PS over the course of the experiment with the exception of Zn on PS. As a result, we show a significant interaction between these types of microplastics and heavy metals, which can have implications for marine life and the environment. These results strongly support recent findings where plastics can play a key role as vectors for heavy metal ions in the marine system. Finally, our findings highlight the importance of monitoring marine litter and heavy metals, mainly associated with antifouling paints, particularly in the framework of the Marine Strategy Framework Directive (MSFD).
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The presence of microplastics in aquatic ecosystems is a topical problem and leads to the need of appropriate and reliable analytical methods to distinctly identify and to quantify these particles in environmental samples. As an example transmission, Fourier transform infrared (FTIR) imaging can be used to analyze samples directly on filters without any visual presorting, when the environmental sample was afore extracted, purified, and filtered. However, this analytical approach is strongly restricted by the limited IR transparency of conventional filter materials. Within this study, we describe a novel silicon (Si) filter substrate produced by photolithographic microstructuring, which guarantees sufficient transparency for the broad mid-infrared region of 4000–600 cm-1. This filter type features holes with a diameter of 10 μm and exhibits adequate mechanical stability. Furthermore, it will be shown that our Si filter substrate allows a distinct identification of the most common microplastics, polyethylene (PE), and polypropylene (PP), in the characteristic fingerprint region (1400–600 cm-1). Moreover, using the Si filter substrate, a differentiation of microparticles of polyesters having quite similar chemical structure, like polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), is now possible, which facilitates a visualization of their distribution within a microplastic sample by FTIR imaging. Finally, this Si filter can also be used as substrate for Raman microscopy—a second complementary spectroscopic technique—to identify microplastic samples. Graphical Abstract Optical and FTIR images of a microplastic model sample of PET and PBT on the novel Si filter substrate. The distribution of this quite similar polymers within a microplastic sample is visible by choosing a band region of 1060–1033 cm-1 for PET and of 955–925 cm-1 for PBT
Article
We investigated the occurrence and distribution of microplastics in surface water from the Three Gorges Reservoir. Nine samples were collected via trawl sampling with a 112 μmmesh net. The abundances of microplastics were from 3407.7 × 10(3) to 13,617.5 × 10(3) items per square kilometer in the main stream of the Yangtze River and from 192.5 × 10(3) to 11,889.7 × 10(3) items per square kilometer in the estuarine areas of four tributaries. The abundance of microplastics in the main stream of the Yangtze River generally increased as moving closer to the Three Gorges Dam. The microplastics are made exclusively of polyethylene (PE), polypropylene (PP), and polystyrene (PS). Together with microplastics, high abundance of coal/fly ash was also observed in the surface water samples. Comparing with previously reported data, microplastics in the TGR were approximately one to three orders of magnitudes greater, suggesting reservoirs as potential hot spot for microplastic pollution. Copyright © 2015 Elsevier Ltd. All rights reserved.