Ecological Risk Assessment of Heavy Metal Contamination in Water, Sediment, and Polychaeta ( Neoleanira Tetragona ) from Coastal Areas Affected by Aquaculture, Urban Rivers, and Ports in South Sumatra

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INTRODUCTION
Pollutants in coastal environments around the world have now become a global concern because of their impact on ecosystems [Yuan et al., 2020].In recent years, the growth of anthropogenic activities such as agriculture, mining, aquaculture, ship transportation, and urbanization along coastal areas has led to the degradation of coastal ecosystems, which ultimately affect both living and non-living organisms (Almaniar et al., 2021;Dan et al., 2022;Shimod et al., 2022).Organisms that live on the coast, such as mangrove groups, annelids, gastropods, cephalopods, and fish, have an Ecological Risk Assessment of Heavy Metal Contamination in Water, Sediment, and Polychaeta (Neoleanira Tetragona) from Coastal Areas Affected by Aquaculture, Urban Rivers, and Ports in South Sumatra important role in maintaining ecosystem sustainability (Fitria et al., 2023;Rozirwan et al., 2023).Heavy metals are considered pollutants that carry many ecological risks due to their high toxicity, non-degradability, bioaccumulation, and biomagnification (Oluwagbemiga et al., 2019;Taslima et al., 2022).Heavy metals are divided into essential and non-essential categories (Slobodian et al., 2021).Essential metals function as protein cofactors in various biological processes but can be toxic if the concentration exceeds a certain threshold (Smethurst and Shcherbik, 2021;Jomova et al., 2022).Non-essential metals have no biological function and are toxic to organisms, even in small amounts (Ali et al., 2019;Romero-Estévez et al., 2023).
Both essential and non-essential metals in high amounts can cause adverse health effects [Wang et al., 2020].Exposure to toxic environments is very concerning, such as from aquaculture activities, urban rivers, and ports where increased levels of toxic metals such as lead (Pb) and copper can be detected even far from their sources [Purwiyanto et al., 2020].Heavy metal pollutants that end up in aquatic ecosystems will continuously settle to the bottom of the waters and accumulate in the biota (Elfidasari et al., 2020;Melake et al., 2023).Different biota may respond differently to metal toxicity due to adaptation to their local environment [Ghosh et al., 2021].For example, metal concentrations influenced by industrial activities may exhibit more toxic effects than in relatively natural and conservation environments (Liu, Y. et al., 2020;Su et al., 2022;Rozirwan et al., 2022).Sediments were identified as the main reservoir of heavy metal pollutants, which are the main habitat for biota, especially in benthic species groups (molluska, crustaceans, and polychaeta), fish, and shrimp [Pandiyan et al., 2021].In the food chain system, this occurs due to the biomagnification of heavy metal pollutants, causing various types of health problems in humans and other animals (Singh et al., 2023).Heavy metals can cause damage to various organs, including the nervous system, liver, lungs, kidneys, stomach, skin, and reproductive system [Hama Aziz et al., 2023].
The benthic macroinvertebrate community is one of the most effective bioindicators of environmental health because of its importance as a major food source for many fish, birds, and mammals, as well as its effect on sediment stability and geochemical composition (Rozirwan et al., 2021;Delgado et al., 2023;Rozirwan et al., 2023a).The main habitat of benthic macroinvertebrate species is sediment, which may have a high level of contamination with heavy metals [Bendary et al., 2023].They live in sediments for long periods, and their current feeding strategy involves consuming sediment particles, resulting in maximum contaminant exposure in both sediment and pore water.The characteristics can enable macrobenthic invertebrates to indicate environmental pollution and offer the possibility of being used as a bioindicator of pollution in coastal areas (Mangadze et al., 2019;Eriksen et al., 2021).Among all benthic taxa, polychaetes are often the most abundant taxonomic group in estuarine ecosystems and are key elements in estuarine and coastal diets [Nogueira et al., 2023].
This study aims to assess the ecological risk of Cu and Pb heavy metal concentrations in water, sediment, and polychaeta in coastal areas affected by aquaculture, urban rivers, and ports.The choice of Cu and Pb for water analysis is influenced by their potential environmental impact and their relevance to human health.These metals are commonly monitored in water quality assessments due to their toxicity and potential to contaminate water sources.Lead, in particular, is known for its harmful effects on the nervous system and other organs, especially in high concentrations.This assessment uses a geochemical approach such as the bioconcentration factor (BCF), geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI), which function for quality interpretation and evaluation of anthropogenic influences on sediments and biota [Mugoša et al., 2016].The author wants to emphasize the fact that this type of research on water quality, sediment, and biota at three different locations based on pollution sources was conducted for the first time in South Sumatra.A combination of ANOVA statistical methods and various geochemical approaches is used to assess the distribution of heavy metals, which can later be applied to other similarly contaminated coastal areas.

Study area and sampling
This research was carried out from July to December 2021.Water, sediment, and polychaeta were taken at three locations with five different stations from around the industrial area: the Banyuasin coast of South Sumatra, which includes the Barong River, Musi River Estuary, and Tanjung Api-api port (Figure 1).Water samples were taken at each station and preserved by adding nitric acid (HNO 3 ) until the pH was <2.Sediment and polychaeta were taken using a grab pipe (30×10 cm) weighing as much as 250 g (Rozirwan et al., 2021b).The samples that had been taken were then stored in the coolbox.Sample identification has been carried out at the Marine Bioecology Laboratory.Sample preparation and destruction have been carried out at the Oceanography and Marine Instrumentation Laboratory, Department of Marine Science, FMI-PA, Sriwijaya University, and analysis for concentrations of Pb and Cu has been carried out at the UPTD of the South Sumatra Provincial Land and Environment Service.

Environmental parameters
Water quality measurements were carried out in situ with three repetitions consisting of temperature, salinity, dissolved oxygen (DO), and pH.Grain size analysis was carried out using the sieve shaker method [Romano et al., 2017].In determining the type of sedimentary substrate, including sand, gravel, silt, and clay, using Shepard's triangle analysis with Microsoft Excel V.2019 (EpiGear Intl, Queensland, Australia)[Kusumaningtyas, 2023].

Sample preparation and destruction
The water sample preparation stage was carried out by filtering using 0.45 µm Whatman paper [Agasti, 2021].Meanwhile, sediment preparation was done by cleaning it from foreign objects, drying it in an electric oven at 60°C for 30 minutes, grinding it into powder until it had fine particles, and storing it in a polyethylene bottle [Smeds et al., 2022].Next, the polychaeta samples were cleaned and crushed using a pestle and mortar [Rapi et al., 2020].Destruction that has been carried out using wet destruction refers to (Gao et al., 2021;Rizk et al., 2022).Put 50 mL of the water sample into the Erlenmeyer and add 5 mL of HNO 3 , then heat it with a C-MAG HS 7 hotplate stirrer until the water sample reaches 15-20 mL.Furthermore, the sediment is destroyed by acid by putting ± 3 g of sample into the Erlenmeyer and adding 25 ml of distilled water to be heated on a hotplate at a temperature of 105-120°C.Mix 5 mL of HNO 3 and wait until the volume reaches 10 mL.After removing and cooling, add 5 ml of concentrated HNO 3 and 1 ml of HClO 4 .The sample was heated again until white smoke appeared and was clear, followed by heating for 30 minutes.After cooling, it was filtered using quantitative filter paper with a pore size of 8.0 µm.
The destruction of polychaeta samples was carried out by wet destruction to determine heavy metal elements [Moltedo et al., 2019].The sample that was weighed is put into an Erlenmeyer, and HNO 3 (5-10 ml) and H 2 O 2 (2 ml) are added.Digestion is carried out by setting up a microwave program.The digests were transferred to 50 mL vials with ultra-distilled water and stored in polyethylene containers at room temperature until further measurement.

Atomic absorption spectroscopic measurement
Measurement of the concentration of heavy metals Pb and Cu using an atomic absorption spectrophotometer (Shimadzu AA-7000) with a wavelength of 283.3 nm for Pb and 324.7 nm for Cu (Zhong et al., 2016;Susilowati et al., 2022).

Quality standards
The concentrations of heavy metals in water, sediment, and polychaeta obtained from the analysis results were further compared with the quality standard values (Table 1).

ECOLOGICAL RISK ASSESSMENT Bioconcentration factor (BCF)
Metal absorption by biota from sediments occurs through a process known as bioaccumulation.The BCF value is used to determine metal bioaccumulation in polychaeta from sediments [Almahasheer, 2019].

Geoacumulation index (I geo )
Igeo quantitatively evaluates the extent of heavy metal contamination and assigns pollution levels according to the classification criteria (Zhang et al., 2021;Xie et al., 2022b).

Contamination factor (Cf)
A contamination factor is a condition in which something is polluted by another element that has a certain effect [Antoniadis et al., 2019].

Pollution load index (PLI)
The pollution load index is used to determine the quality of pollution.The pollution load index value uses the formula (Shaheen et al., 2019;Singh et al., 2020).

Statistical analysis
The data were tested for homogeneity of variance with the Levene test and for normality of distribution with the Shapiro-Wilk test.Significant differences within each region by pollution source were assessed by one-way analysis of variance (ANOVA), followed by a post-hoc Tukey test if the conditions were met (Dolagaratz et al., 2018).The level of significance was p < 0.05.All statistical analyses were performed using the IBM SPSS V.26 application.

Environmental parameters
The results of measuring the quality of the aquatic environment at three different locations have various values (Table 2).The DO and pH values at the study sites varied quite a lot, with a range of 4.67-7.34mg/L and 6.35-8.10categorized as normal and evenly distributed across all observation stations.Salinity values varied, with a range between 0 and 25 PSU.Based on the results, the lowest salinity value was found at station 6, namely 0 PSU, and the highest salinity was found at station 2, which was 25.0 PSU.The temperature measurement results obtained ranged from 24.35 to 30.3 °C.The results of determining the type of substrate at three locations with the highest percentage of sediment fraction at each station were dominated by clay.
The chemical physics of the aquatic environment plays an important role in the survival of fish, invertebrates, and all organisms in the water.Anthropogenic-induced release of inorganic nutrients impacts water quality and affects macroinvertebrate communities [Duque et al., 2022].Dissolved oxygen, pH, salinity, and temperature have varied measurements at each observation station, which are influenced by aquaculture, urban river, and port activities.Dissolved oxygen in the study area is still relatively good as a place for aquatic organisms to live.Bozorg-Haddad et

Description of polychaeta
The polychaeta species found in the field is Neoleanira tetragona (Figure 2).Polychaetes-Polychaetes found in the field are morphologically characterized by segmented bodies (metamer), which are red, antennae on their heads, and many legs all over their bodies (chaetae).
Polychaeta found at observation stations live in and on the surface of the sediments.The research location is domiciled in a mangrove forest community with a mud substrate type [Fitria et al., 2023].At this research location, birds were also found looking for food in the form of polychaeta (Rozirwan et al., 2022).The diversity of polychaeta is highest and most abundant in marine or estuarine habitats and decreases in freshwater habitats (Quirós-Rodríguez et al.  meters, and includes highly motile swimmers or crawlers as well as tube-dwelling and tube-dwelling species [Schulze, 2023].In particular, polychaetes were commonly used in ecotoxicological studies because of their abundance, easy capture, and assimilation of heavy metals from sediments through their skin and gut (Dolagaratz et al., 2018).

Heavy metals concentration
The concentrations of heavy metals Pb and Cu in water, sediment, and polychaeta from three areas affected by aquaculture, urban rivers, and ports are summarized in Figure 3.The concentration of the heavy metal Pb in water ranged from  Pb enrichment is directly related to anthropogenic activity.There are large-scale ports, aquaculture, and urban rivers or waste disposal on the Banyuasin Coast (Purwiyanto et al., 2020;Almaniar et al., 2021).Pb enrichment can cause a decrease in ecosystem health (Liu et al., 2022).On the other hand, the concentrations of Pb and Cu in sediments were higher than in water because they had accumulated for a long time.According to Yu et al., (2022) this could be due to the influence of dynamic water conditions.
The concentrations of heavy metals Pb and Cu in the sediments obtained did not exceed the quality standards (Table 1).This means that the sediment in the waters of the study location is still classified as a good habitat for the macrozoobenthos group.Observation stations 11-15 in areas affected by port activities have a higher concentration than aquaculture and urban river areas (Figure 3B).The port is a place for loading and unloading export-import goods, raising and lowering passengers, and inter-island trade so it becomes a land-sea coordinated area that is heavily influenced by human activities (Wang et al., 2019).These activities can release pollutants into the water and sediments (Lim et al., 2022).Generally, ports are semi-enclosed water areas with limited water circulation and slow renewal after being polluted.This causes this area to be vulnerable to a large accumulation of pollutants, especially in sediments, which are considered anthropogenic pollution hotspots [Gu and Gao, 2019].Pollutants at observation stations 1-5 in areas affected by aquaculture activities are lower than those in port areas.This can be caused by sources of pollution, which can come from leftover feed and cultivated manure in the form of suspended and dissolved solids that are transported through the water flow, which is a source of organic matter in pond land.Other factors can come from the activities of fishing boats transporting pond products (Herbeck et al., 2013;Mustafa et al., 2022).Another factor can come from the activities of fishing boats carrying pond products (Prasetiawan et al., 2022;Lim et al., 2022).Whereas at observation stations 6-10, the areas affected by urban river activity had concentrations of Pb and Cu metals that were not significantly different (P > 0.05) from the cultivation areas.Pollution in the Musi River Estuary is caused by domestic and industrial activities [Tjahjono et al., 2022].Domestic activity is said to have more impact than industry.Its condition can be seen in organic decay due to household waste [Abdel-Shafy and Mansour, 2018].Not only that, Gaete et al., (2017) reported that metal-containing residue receptors from anthropogenic activities in river mouths have different basin levels.
The results in Figure 3C show fluctuations in the concentrations of Pb and Cu metals in the polychaeta collected from three different locations.These data also indicate that the polychaeta contains relatively low levels of lead and copper.This may be due to environmental conditions and the concentration of heavy metals in sediments, which is also relatively low.The concentrations of the heavy metals Pb and Cu in the polychaeta obtained did not exceed the established quality standards (Table 1).Each observation station, starting from areas affected by aquaculture activities, urban rivers, and ports, was not significantly different (P > 0.050) for Pb and Cu concentrations.The concentration of heavy metals can increase depending on the environmental conditions of the waters (Tchounwou et  ).This indicates that the accumulation of heavy metals in polychaeta can be used as an instrument for monitoring environmental and ecological risks in marine waters.

Ecological risk assessments of heavy metals concentration
The results of the ecological risk assessment of heavy metal pollution in the aquaculture area are summarized in Table 4, the urban river area in Table 5, and the port area in Table 6.Overall, the results of polychaeta bioconcentration factor (BCF) from aquaculture areas, urban rivers, and harbors in carrying out soil metal bioaccumulation are an excluder for all Pb heavy metals (0.0276, 0.0026, 0.0113 ) and Cu (0.0250, 0.0125, 0.0155).The geo-accumulation index shows uncontaminated properties for Pb (-1.3458, -2.5823, -1.0097) and Cu (-4.6688, -5.6919, -2.5445).Contamination factor (CF) showed enrichment of various metals for Pb (-0.9882, 0.2724, and 0.7509) and Cu (0.0449, 0.0404, and 0.2634), indicating that heavy metal contamination did not occur high on the Banyuasin Coastal Shelf.The PLI ranges from 0.103796 to 0.4385, which indicates that the quality of pollution in these three areas is not polluted.
Water quality assessments often focus on a select number of contaminants based on regulatory standards, local concerns, or specific risks associated with particular pollutants in a given region.Other similar studies in different geographical locations was presented in Table 7  Honghu Lake, Liangzi Lake, Daye Lake and East Lake are located on the Jianghan Plain, China Agriculture, transportation, and chemical industry Disruption of heavy metal pollution control in lakes with high human activity loads [Wang et al., 2023] relatively high levels of heavy metal (Hg and Cd) pollution due to its semi-enclosed nature in the Yellow Sea facing various external pressures, including increased metal pollution weight in seawater and sediment and the expansion of land-based ponds, vessel (seaweed) and fish farming, and port operations.This ecological risk assessment of heavy metal pollution is very helpful in describing the environmental status.Moreover, by using this index, the trend of load pollution from time to time can be understood.Based on the pollution status, stakeholders can formulate appropriate control measures [Goher et al., 2017].

CONCLUSIONS
Total concentrations of Pb and Cu were evaluated statistically to have significant differences (P < 0) in water and sediment samples collected from areas affected by aquaculture, urban rivers, and Meanwhile, the polychaeta of each area did not differ significantly (P > 0).The concentration of Pb in the water at all stations exceeded the quality standard that had been set; Cu was not detected.Pb and Cu concentrations in sediments and polychaeta (Neoleanira tetragona) are still below the quality standards.The levels of Pb and Cu contamination in sediments and polychaeta were also evaluated by bioconcentration factor, geoaccumulation index, contamination factor, and ecological risk assessment.The observed heavy metals Pb and Cu did not accumulate in the polychaeta; the concentrations of Pb and Cu were found to be low in the sediment, resulting in no significant ecological risk.
Stations 1 to 5 were affected by aquaculture activities in the Barong River area and were also included in the Sembilang National Park conservation area (Rozirwan et al., 2022).Stations 6 to 10 were affected by urban rivers with various activities such as air transportation, fishing areas, agricultural activities, and community organizations around the Musi River Estuary (Saputra et al., 2022; Rozirwan et al., 2021a).Stations 11 to 15 were affected by port activities such as ship services, handling of loading and unloading of crates, embarkation and disembarkation of passengers, and stacking services (Rozirwan et al., 2022a; Rebai et al., 2022; Rozirwan et al., 2023b).

Figure 1 .
Figure 1.Map of sampling locations al. (2021) reported that most aquatic plants and animals require oxygen to survive and cannot survive in water with dissolved oxygen less than 5 mg/L.The higher the DO level, the more the macrozoobenthos can carry out their biological and physiological functions properly so that they can grow and develop(Duque et al., 2022;Bonifazi et al., 2023).The high and low pH were influenced by the fluctuations of oxygen and carbon dioxide in the waters.The area affected by port activity at stations 11-15 has a lower pH because it is influenced by Bangka Strait water input.This is consistent with [Rugebregt and Nurhati, 2020] The pH is increasing toward the open sea.The lowest salinity value is in the port area.According to(Rozirwan et al., 2022) that the salinity around the area varies.This is because the influence of fresh water and seawater is very fluctuates depending on conditions at high and low tides.Water temperature values tend to be high in aquaculture areas.This is related to the infiltration of sunlight into the surface and deeper layers and the movement of water masses(Sui et al., 2022;Li et al., 2022).The distribution of polychaeta can be affected by changes in salinity in the estuary area, which will result in a decrease in the number of macrobenthos(Liu et al., 2023).The clay substrate is the type of substrate favored by polychaeta.According toRyabchuk et al., (2020) clay is a substrate that strongly supports the life of polychaeta.The smooth substrate has a stronger ability to bind organic matter compared to the coarser substrate(Chenot et al., 2017;Rizqydiani et al., 2018;Huang and Gu, 2019).The smoother the sediment, the greater the strength to bind heavy metals[Özşeker et al., 2022].
, 2023;Kohlenbach et al., 2023).Polychaeta also has an important role in determining environmental fertility and is also used as biomonitoring of marine health for indicators of organic pollution(Qu et al., 2016;Kies et al., 2020).Phylum Annelida inhabits marine, freshwater, and terrestrial habitats, ranging in size from microscopic to several

Table 1 .
Heavy metal quality standards

Table 2 .
Water environment quality parameters While the areas affected by urban river activities, in general, did not detect Pb metal.Outliers from Pb indicate higher enrichment.Lead (Pb) is a metalloid that is often used as a poison (Usman et al., 2020; Silva-Gigante et al., 2023).As commonly used in ship transportation fuel and industrial waste [Chen et al., 2022].
). nd: not detected al., 2012; Briffa et al., 2020; Mitra et al., 2022).Heavy metals can move into the bodies of organisms through the food chain [Steinhausen et al., 2022].Apart from going through the food chain, heavy metals can enter the body of the polychaeta through the habits and diet of the polychaeta.Macrozoobenthos has filter feeder Tabel 3. Comparison of Pb and Cu concentrations associated with polychaetes from different locations in the world Dong et al. (2023)1]]) being reported byPerumal et al., (2021)calculated EF, CF, Cd, mCd, Cp, RI, and Igeo Indices on Cu, Zn, Pb, and Cr in the Thondi coastal region of the southeastern coast of India induced by anthropogenic inputs.In contrast, the evaluation of the high metal pollution load index located in the Al-Salam Lagoon (Red Sea) indicates uncontrolled pollution due to anthropogenic impacts[Mannaa et al., 2021].Likewise Iskenderun Bay, Turkey, with the risk of ecological contamination[Kutlu et al., 2021].Dong et al. (2023)reported status of habitat quality (EcoQs) shows that although several locations in Laoshan Bay have

Table 4 .
The results of ecological risk assessment of heavy metal concentrations from areas affected by aquaculture The results of ecological risk assessment of heavy metal concentrations from areas affected by urban river The results of ecological risk assessment of heavy metal concentrations from areas affected by port

Table 7 .
Study of heavy metals Pb and Cu in some characteristics of aquatic environment