Domestic Discharges Research Articles

Environmental Assessment and Restoration of the Hunjiang River Basin Based on the DPSIR Framework

The Hunjiang River, a vital water system in northeastern China, has suffered severe ecological damage due to overexploitation. This study analyzes the basin’s environmental conditions from 2016 to 2020, identifies key restoration factors, and examines practical restoration projects. Investigating five major pollutants (permanganate index, chemical oxygen demand (COD), biochemical oxygen demand, ammonia nitrogen, total phosphorus) in eight sections, the study finds the Xicun section most polluted, mainly from Baishan City’s industrial and domestic discharges. The ammonia nitrogen concentration at the Zian section also shows deterioration. Using a DPSIR (Driving forces, Pressures, State, Impacts, Responses) framework, the study elucidates the relationship between environmental and socio-economic issues. Results indicate that population changes, industrial development, and water resource management have complex ecological impacts. Evaluating the urban water resource carrying capacity with the entropy weight method and correlation coefficient weighting method, the study finds that increasing forest coverage, improving wastewater treatment efficiency, and reducing COD emissions are crucial. Quantitative assessment of integrated protection and restoration projects involving mountains, rivers, forests, farmlands, lakes, and grasslands demonstrates their positive impact. This research reveals the interplay between the ecological environment and social factors, proposes practical restoration measures, and clarifies project effects, providing reliable decision-making schemes for policymakers.

Characterizing nitrogen deposited on urban road surfaces: Implication for stormwater runoff pollution control

Nitrogen (N) is one of the most important pollutants on urban road surfaces. Understanding the N deposition forms, load characteristics, and influential factors can help to provide management and control strategies for road stormwater runoff pollution. This study focuses on a highly urbanized area in Guangzhou, China, and presents the characteristics of both dissolved and particulate N deposition forms as well as their correlations with land-use types and traffic factors. In addition, an artificial neural network (ANN) based classification model is utilized to estimate N pollution hotspot area and total nitrogen (TN) flux from road to receiving water bodies. The results showed that N on urban road surfaces mainly existed in the form of particulate organic nitrogen. Land use types dominated by residential area (RA) and urban village (UV) have higher TN build-up loads. Geodetector analysis indicated that land use has a greater impact on nitrogen build-up loads than traffic factors. Through classification and estimation using the ANN model, RA, and UV were classified as hotspot areas, and the TN flux from roads in the study area was calculated to be 3.35 × 105 g. Furthermore, it was estimated that the annual TN flux from roads in Guangzhou accounts for 19 % of the city's total urban domestic discharge. These findings are expected to contribute to the pollution control of stormwater runoff from urban road surfaces and provide valuable guidance for enhancing the ecological health of urban water environments.

Sources of persistent and mobile chemicals in municipal wastewater: a sewer perspective in Leipzig, Germany.

Persistent and mobile (PM) chemicals spread in the water cycle and have been widely detected, yet information about their sources is still scarce. In this study, 67 PM chemicals were analyzed in 19 wastewater samples taken in the sewer system of the city of Leipzig, Germany, covering different industrial, clinical, and domestic discharges. A total of 37 of these analytes could be detected, with highly variable median concentrations between substances (median: 0.5-800µg L-1) and for single substances between samples (e.g., 1,4-diazabicyclo[2.2.2]octane) by up to three orders of magnitude, with the highest single concentration exceeding 10mg L-1 (p-cumenesulfonic acid). The emission of PM chemicals into the sewer system was classified as stemming fromdiffuse (14 analytes) or point sources (23analytes), while 9 analytes fulfill both criteria. Many so-called industrial chemicals were also discharged from households (e.g., tris(2-chloroethyl) phosphate or 1H-benzotriazole). Examples for analytes showing specific sources are tetrafluoroborate (traffic-related industry and metal production and finishing), ε-caprolactam (large-scale laundry), or cyanuric acid (likely swimming pool). Furthermore, a correlation between 1-cyanoguanidine and guanylurea was observed for the traffic-related industry. This study outlines that sewer sampling can provide valuable information on the sources of PM chemicals. This knowledge is a prerequisite for their future emission control at source or substitution as an alternative to end-of-pipe treatment in municipal wastewater treatment plants.

New approach to domestic grey water footprinting: country-scale accounting using statistical methods in Türkiye

ABSTRACT This study aimed to develop an approach for country-scale domestic grey water footprint (GWFdomestic) accounting and examine spatio-temporal differences using statistical methods. In this scope, the GWFdomestic was calculated as the amount of water required to reduce the total nitrogen concentrations of domestic wastewater released into receiving media from 81 cities in Türkiye. GWFdomestic values were estimated based on the data on wastewater amount and applied wastewater treatment process. GWFdomestic was calculated by dividing the pollutant load of discharged water by the critical concentration in the surface water. The empirical results showed that (a) the produced wastewater amount increased up to 125 m3/year in some cities. (b) GWFdomestic values showed a difference between 330 and 1,900 depending on the level of treatment, and the average value was about 750 m3/ca.year. (c) A total of 81 cities were grouped under four categories, and applied water treatment technology was the main characteristic of this classification. (f) GWFdomestic has not statistically significantly changed over time in a large part of the country. It can be concluded that country-scale GWFdomestic accounting can assist water managers in developing prevention measures by analyzing spatio-temporal differences in the water footprint of domestic discharges.

Heavy Metals in the Sediments of Dongshan Bay, China: Sources, Distribution, and Controlling Factors

Fifty-one surface sediment samples from Dongshan Bay, China, were analyzed for heavy metals to evaluate their distribution, pollution status, and controlling factors. The enrichment factor is suggestive of the potential pollution status, ranging from minimal to moderate enrichment, for Pb, As, Zn, and Hg, with one site showing significant enrichment in As. A principal component analysis and the geochemical characteristics indicate that heavy metal concentrations are mainly influenced by clay minerals and Fe oxides, while Pb and Hg levels are also closely linked to the absorption of Mn oxides. Potential pollution is primarily from aquaculture (Cd, Zn, Cu, Pb) and industrial and domestic discharges. Approximately 270 tons of heavy metals were estimated to have been deposited in Dongshan Bay in 2021, highlighting the potential impact of human activities on coastal sediment quality.

The first evidence of microplastic presence in the River Nile in Khartoum, Sudan: Using Nile Tilapia fish as a bio-indicator

The extent of microplastics in African freshwater systems remains less investigated. In Sudan, there is no single study reporting microplastics in water bodies. This scoping study aimed to investigate the presence and characteristics of microplastics (MPs) in Nile Tilapia fish from the River Nile in Khartoum, Sudan. The digestive tracts of the fish were digested using 10% potassium hydroxide, and microplastic particles were extracted by density separation using sodium iodide. 567 particles of different sizes (0.04–4.94 mm), shapes (fibers, fragments, films, foams, and pellets), and colours (mostly green, black, blue, and grey) were identified as microplastics. The average abundance of microplastics was 72.02 ± 62.06 particles/kg, and the average intensity was 18.90 ± 9.17 MPs/fish. Small-sized (<1 mm), fibrous-shaped, and coloured microplastics were most abundant in all samples, representing 56%, 85%, and 84%, respectively. Surface examination by SEM showed signs of fragmentation such as cracks, pits, and pores. Two polymer types (high-density polyethylene and polypropylene) were identified by Raman spectroscopy. The predominance of fibers and fragments (94.5%) over pellets (0.35%) and the apparent signs of fragmentation may indicate that MPs are mostly secondary MPs. Wastewater effluent, domestic discharge, and recreational activities are the potential sources. This scoping investigation provided the first data on microplastic presence in the River Nile in Khartoum, and it could be used to guide future studies to fill research gaps in the region.

Environmental monitoring of the Kavaratti lagoon, Lakshadweep Islands, Arabian Sea using larger foraminiferal distribution

Coral reef environments are known for the proliferation of algal symbiont-bearing foraminifera, which are sensitive indicators of water-quality conditions that support reef development. Keeping this in mind, 18 sediment samples were collected in the Kavaratti lagoon of Lakshadweep in 2004. The foraminiferal distribution and abundance of the major genera Amphistegina, Calcarina, Amphisorus and miliolids were compared with those reported nearly three decades ago. The aim was to identify changes in the foraminiferal data within the lagoon over time, through time-gap-sampling, to be able to assess environmental stress if any. The total foraminiferal number (TFN) in the lagoon ranges between 45 and 983 specimens per gram of dry sediments. The average TFN in the northern part of the lagoon (506/g) is lower than that in the southern part of the lagoon (612/g). Amphistegina and Calcarina, both being algal-symbiont-bearing foraminifera, show the tendency to occupy shallower depths of the lagoon. Amphisorus prefer the northern part of the lagoon, due to the prevalence of comparatively stronger currents. Over the past three decades, TFN in the lagoon has on an average gone down from 65,667 in 1976 to 56,100 (present study) specimens per 100 g of sediments. The larger foraminiferal distribution in the Kavaratti lagoon has slightly but undisputedly undergone quantitative and distributional changes over the past three decades. The FORAM Index suggests conducive environment for coral growth in the lagoon. However, definite deterioration due to dredging in the northern lagoon is indicated by the assemblage. The study also records signatures of domestic discharge and predicts a larger impact on the corals since 2004 to 2024.

Seasonal variation and dissolved organic matter influence on the distribution, transformation, and environmental risk of pharmaceuticals and personal care products in coastal zone: a case study of Tianjin, China

Pharmaceuticals and personal care products (PPCPs) are emerging contaminants that have raised urgent environmental issues. The dissolved organic matter (DOM) plays a pivotal role on PPCPs’ migration and transformation. To obtain a comprehensive understanding of the occurrence and distribution of PPCPs, a seasonal sampling focused on the riverine system in coastal zone, Tianjin, Bohai Rim was conducted. The distribution and transformation of thirty-three PPCPs and their interaction with DOM were investigated, and their sources and ecological risks were further evaluated. The total concentration of PPCPs ranges from 0.01 to 197.20 μg/L, and such value is affected by regional temperature, DOM and land use types. PPCPs migration at the soil-water interface is controlled by temperature, sunlight, water flow and DOM. PPCPs have a high affinity to the protein-like DOM, while the humus-like DOM plays a negative influence and facilitates the PPCPs’ degradation. It is also found that protein-like DOM can represent point source pollution, while humus-like substances indicate non-point source (NPS) emission. Specific PPCPs can be used as markers to trace the source of domestic discharge. Additionally, daily use PPCPs such as ketoprofen, caffeine and iopromide are estimated to be the main risk substances, and the PPCPs ecological risk varies on space, season and river hydraulic condition.

The Relationship of Bristle Worm, Protodorvillea kefersteini (McIntosh, 1869) (Eunicida, Dorvilleidae) Abundance with Environmental Variables in Çardak Lagoon (Turkish Straits) Exposed to domestic Discharge

The Relationship of Bristle Worm, Protodorvillea kefersteini (McIntosh, 1869) (Eunicida, Dorvilleidae) Abundance with Environmental Variables in Çardak Lagoon (Turkish Straits) Exposed to domestic Discharge

Prioritization of control factors for heavy metals in groundwater based on a source-oriented health risk assessment model

Heavy metals (HMs) in groundwater seriously threaten ecological safety and human health. To facilitate the effective management of groundwater contamination, priority control factors of HMs in groundwater need to be categorized. A total of 86 groundwater samples were collected from the Huangpi district of Wuhan city, China, during the dry and wet seasons. To determine priority control factors, a source-oriented health risk assessment model was applied to compare the pollution sources and health risks of seven HMs (Cu, Pb, Zn, Cr, Ni, As, and Fe). The results showed that the groundwater had higher As and Fe contents. The sources of HM pollution during the wet period were mainly industrial and agricultural activities and natural sources. During the dry period, origins were more complex due to the addition of domestic discharges, such as sewage wastewater. Industrial activities (74.10% during the wet period), agricultural activities (53.84% during the dry period), and As were identified as the priority control factors for groundwater HMs. The results provide valuable insights for policymakers to coordinate targeted management of HM pollution in groundwater and reduce the cost of HM pollution mitigation.

Evaluating the effects of geochemical and anthropogenic factors on the concentration and treatability of heavy metals in Awash River and Lake Beseka, Ethiopia: arsenic and molybdenum issues

In the Awash River basin (Ethiopia), massive urbanization and industrialization, driven by rapid development and human settlement, are detrimental to the environment and human health as pollutants such as heavy metals (HMs) find their way into water bodies without proper treatment. The purpose of this study was to assess the HMs content and pollution sources within the basin. In this context, a total of 205 samples were collected from 21 surface water sampling stations. Heavy metal concentrations were measured using the Perkin Elmer NexION 350 ICP-MS with inductively coupled plasma. Findings demonstrate that high levels of HMs, such as Al, Mn, Mo, As, V, Fe, and Ba were exhibited with the value of 1257 μg/L, 626.8 μg/L, 116.7 μg/L, 61.2 μg/L, 100.5 μg/L, 1082.7 μg/L, and 211.7 μg/L, respectively. Among 20 HMs analyzed, 20% of the parameters within the study area were above the WHO limit for drinking water; Al (157 μg/L), V (100.5 μg/L), Fe (1082.7 μg/L), Mn (626.8 μg/L), and Mo (103.8 μg/L) were exhibited at sites along the river system. Likewise, 57% of water samples showed high values of As at many stations down the river systems. In particular, high HM concentrations seen in the upper Awash are primarily controlled by anthropogenic activities such as untreated industrial, agricultural, and domestic discharges, while the high HM concentrations in the middle Awash samples were likely due to the influence from the Lake Beseka that has high HM concentrations due to geological process. In conclusion, securing potable water for the rapidly increasing population in Addis Ababa and in the watersheds of Awash is unsafe to sustain the environment and the human health.

Sediment-bound hazardous trace metals(oid) in south-eastern drainage system of Bangladesh: First assessment on human health

Despite the beneficial aspect of a natural drainage system, increasing human-induced activities, which include urbanization and growth in industrialization, degrade the ecosystem in terms of trace metal contamination. In response, given the great importance of the south-eastern drainage system in Bangladesh, a detailed evaluation of the human health risk as well as the potential ecological risk of trace metals (Be, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, V, Zn, and As) in Karnaphuli riverbed sediment was conducted. Mean levels of the elements in mg/kg were As (5.62 ± 1.47); Se (0.84 ± 0.61); Hg (0.37 ± 0.23); Be (1.17 ± 0.49); Pb (15.62 ± 8.42); Cd (0.24 ± 0.33); Co (11.59 ± 4.49); Cr (112.75 ± 40.09); Cu (192.67 ± 49.71); V (27.49 ± 10.95); Zn (366.83 ± 62.82); Ni (75.83 ± 25.87). Pollution indicators, specifically contamination factor (CF), pollution load index (PLI), degree of contamination (Cd), enrichment factor (EF), geo-accumulation index (Igeo), and potential ecological risk index (RI), were computed to assess sediment quality. For the first observation of health risk, chronic daily intake (CDI), hazard quotient (HQ), hazard index (HI), carcinogenic risk (CR) and total carcinogenic risk (TCR) indices were calculated. According to the results, CDI values through the ingestion route of both the adult and child groups were organized in the following descending mode respectively: Zn > Cu > Cr > Ni > V > Pb > Co > As > Se > Be > Cd > Hg. The non-carcinogenic risks were generally low for all routes of exposure, except HQingestion was slightly higher for both adults and children. The calculated hazard index (HI) was, nevertheless, within the permitted range (HI < 1). Similarly, none of the metals exhibited any carcinogenic risks, as all CR values were within the 10−4-10−6 range. The need for authoritative efforts and water policy for the sake of the surrounding ecosystem and human health in the vicinity of the examined watershed is strongly felt as an outcome of this study. The purpose of this study is to protect public health by identifying trace metal sources and reducing industrial and domestic discharge into this natural drainage system.

Screening of Pharmaceutical Pollutants Along with Emerging Contaminants in the Sediments of the Periyar River, Located in Kerala (India) by Using High-Resolution Mass Spectrometry (UPLC-Q-ToF-MS).

In this study, ultra-performance liquid chromatography coupled with a quadruple time-of-flight mass spectrometry (UPLC-Q-ToF-MS) was employed to screen and identify pharmaceutical pollutants and emerging contaminants (ECs) in the Periyar River near Aster Medicity hospital, the dumping yard of Amrutha hospital, and the Vaduthala bridge regions in Kerala, India. The analysis was conducted in both positive and negative ionization modes using electrospray ionization (ESI). The QuEChERS method was employed for initial sediment sample preparation. Among the twenty-five identified ECs, four compounds were identified as pharmaceutical pollutants. This study have great significance as it represents the first comprehensive investigation of pharmaceutical pollutants in these hospital regions, highlighting the urgent need for further analysis and understanding of the situation. The presence of ECs poses an urgent need for attention due to the irreversible harm caused to the riverine ecosystem by the degradation of water quality resulting from industrial and domestic discharge.

Nitrates in Turkish waters: sources, mechanisms, impacts, and mitigation.

Intensive technological developments, rapid population growth and urbanization, and excessive use of nitrogen fertilizers have caused water resources to be contaminated substantially by nitrates in Turkey. The accumulated information should be evaluated to draw a nationwide attention to the problem. The aim of this review article was to highlight the importance of nitrate (NO3) contamination and to discuss the measures to be taken to mitigate the contamination across the nation. Agriculture, especially chemical fertilizers used in irrigated agriculture, was the most important source of NO3 in groundwater. Also, the industrial and domestic discharges substantially contributed to NO3 in both groundwater and surface waters in many cases. The most severe and widespread groundwater (e.g., 344 mg NO3 L-1 in İzmir, 476 mg L-1 in Afyon, 477 mg L-1 in Antalya, and 948.0 mg L-1 in Konya) and surface water contaminations (e.g., 293.8 mg NO3 L-1 in İzmir, 63.3 mg L-1 in Eskişehir, 89.8 mg L-1 in Edirne, and 90.6 mg L-1 in Sakarya) occurred in the regions where intensive agriculture, industrial development, and rapid urbanization were clustered. Well-established irrigation and fertilizer management plans are critical for reducing fertilizer-related NO3 contaminations in the irrigated agriculture. Special attention should be given to the regions where industrially and domestically contaminated running water bodies are in contact with groundwater. Discharge of wastewaters to the streams, creeks, rivers, and lakes should be prevented. Well-designed studies are needed to evaluate potential health effects, including the risk of cancer, of NO3 in drinking water.

Early detection of emerging persistent perfluorinated alkyl substances (PFAS) along the east coast of India

Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) are resistant to breakdown and are now considered global contaminants. However, interest in these recalcitrant compounds among scientists and legislators has grown significantly in recent years. In the present study, we analyzed the level of PFOA and PFOS contamination in surface water from the coastal regions of Tamil Nadu and West Bengal. After solid phase extraction, 49 samples were analyzed by liquid chromatography coupled with mass spectrometry (LOD ≤ 1.5 ng L−1). The PFOA and PFOS present in all samples at the highest concentration were found in the Ennore coastal region (reaching a maximum of 24.8 ng L−1 and 13.9 ng L−1 in CH-6 and CH-14 respectively). Similarly, on the West Bengal coast, concentrations of PFOA ranged from <1.5 to 14.0 ng L−1 and <1.3 to 8.2 ng g−1 in water and sediment respectively. PFOS concentrations in water and sediment ranged from <1.2 to 9.0 ng L−1 and <1.2 to 7.9 ng g−1, respectively. According to the principal component analysis, the majority of the variances (65.04 %) show a positive association, which points to industrial and domestic discharges as significant point sources of these compounds. The results from this study could be used to determine and understand the levels of PFOA and PFOS contamination along the Indian Coast as well as provide baseline information for imminent monitoring investigations. The environmental occurrences of PFOA and PFOS reported in the current study would allow policymakers to take appropriate measures to safeguard coastal ecosystems or reduce the likelihood of contamination, creating a sustainable and healthy environment.

An evaluation of spatial and seasonal distributions of dissolved trace metals in the water of the natural wetlands

The spatial and temporal distributions of trace metals in dissolved forms mainly result from anthropogenic and lithogenic contributions. Surface water samples (∼0.5 m) were collected monthly at respective stations from Setiu Wetland. In this study, the behaviour of trace metals in the dissolved phases along the water column from sampling sites in the Setiu Wetland, Malaysia was investigated. In addition, dissolved organic carbon (DOC) and physical parameters such as salinity, temperature, pH and dissolved oxygen (DO) of the surface water were measured in order to evaluate the relationship between trace metals fractionation with different water quality parameters. Size fractionation study of dissolved trace metals using ultrafiltration technique were also carried out and analysed using inductively coupled plasma mass spectrometry (ICP-MS). Correlation of trace metals with other measured parameters was made to furthermore understand the dynamics of trace metals and its fractionated components in this area. The concentration of dissolved trace metals was in the range of 0.001–0.16 μg/L for Cd, 0.12–2.81 μg/L for Cu, 0.01–1.84 μg/L for Pb, 3–17 μg/L for Fe and 1–34 μg/L for Zn, suggesting the input of anthropogenic sources for trace metals such as municipal, industrial, agricultural and domestic discharge. The periodic monitoring and evaluation of trace metals in wetlands and protected tropical areas is highly recommended.

Brief communication: The northwest Himalaya towns slipping towards potential disaster

Abstract. The NW Himalaya (India) has been one of the most affected terrains of the Himalaya, subject to frequent disastrous landslides owing to active tectonics and multiple precipitation sources. This article focuses on two towns (Joshimath and Bhatwari) of Uttarakhand in the NW Himalaya, which have been witnessing subsidence for decades. Up until 9 January 2023, Joshimath had witnessed widespread cracks in more than 500 houses, which has prompted social unrest in the region. The hillslopes surrounding both towns comprise highly jointed gneisses with schistose interlayer rock mass. Both towns have subsidences and holes in the road, broken retaining walls, and displaced boulders, and the houses have cracks in the walls and holes. Recently, such slope instability phenomena have increased, which is leading to social movements in the region seeking government action such as possible evacuation and rehabilitation. The present study used a continuum-modelling-based slope stability simulation to determine the response of these hillslopes under various loading conditions: gravity, rainfall, building load, domestic discharge, and seismic load. Results revealed that the displacement in these hillslopes might reach up to 20–25 m, which will further aggravate the situation. The occurrence of frequent extreme rainfall in these towns and three major earthquakes, which occurred on 1 September 1803 (Mw 7.8), 20 October 1991 (Mw 6.8), and 29 March 1999 (Mw 6.6), having a hypocentral distance less than 30 km makes such a study more viable for decision making.

Evaluation of the Effects of Riparian Population Activities on the Physicochemical Quality of Water in a Mediterranean River: The Inaouene River (Taza, North East Morocco)

Mediterranean Rivers are often increasingly subjected to stress as a result of riparian population activities. This present study assessed the impact of human activities on the water quality of the Inaouene River in Morocco. For this purpose, water samples were collected from seven sampling stations along the River and analysed. The water of the Inaouene River is characterised by slightly alkaline water pH (7.32-7.59), electrical conductivity (1206.44-3674.14 μS cm-1), very low level of dissolved oxygen (1.98-5.55 mg L-1), BOD5 (45.42-328.7 mg L-1), COD (112.71-468.46 mg L-1). The results classify the Inaouene River’s water in the “moderate to poor” quality range based on Moroccan standards. This water, which is characterised by moderate to severe organic contamination, is also distinguished by a significant allochthone charge from the different riparian urban centres. The multivariate analysis showed a decline in water quality and high amounts of organic matter, nitrogenous and phosphorus in urban centres downstream. Waters from stations located further away from domestic discharge points are less polluted and more oxygenated. Overall, these findings confirmed that the combined effect of anthropogenic activities and the seasonality characteristic of the Inaouene watershed is the main factor that determines water quality.

High production volume chemicals in the most consumed seafood species in Tarragona area (Spain): Occurrence, exposure, and risk assessment.

Seafood consumption has become a potential exposure route towards high production volume chemicals (HPVs) due to the pathway of these compounds reaching the aquatic environment via industrial and domestic discharges. The present study focuses on the determination of phthalate esters (PAEs), organophosphate esters (OPEs), benzothiazoles (BTs), benzotriazoles (BTRs) and benzenesulfonamides (BSAs) in the ten most consumed fish species in Catalonia. A total of 120 commercially available seafood specimens were purchased throughout February 2019-February 2020 in three different stores (supermarket, local market, and local fishmonger) of the city of Tarragona, Spain, to cover the most typical places where seafood can be obtained. ΣOPEs, ΣBTs, ΣBSAs and ΣPAEs concentrations ranged between 5.99 and 139.45ng g-1 w.w., 8.41-54.08ng g-1 w.w., 8.38-304.47ngg-1 w.w and 2.86-323.80ng g-1 w.w., respectively. BTRs were not detected in any of the samples. PAEs and BSAs had similar contributions which combined represented nearly the 70% of detected compounds and sardine resulted as the species with the higher HPVs mean concentration. No considerable threat was posed due to the individual intake of these compounds via seafood consumption.

An overview of the impact of heavy metal accumulation on marine molluscs

Seafood, particularly bivalves, is an excellent source of balanced food. However, due to the rising concentration of heavy metals in the aquatic environment, it can have a negative effect on public health. Heavy metals are common inorganic pollutants in the environment, and their presence poses a significant threat to human beings due to their toxic effect on the biotic system. Various biological and geochemical factors influence the uptake and bioaccumulation of these heavy metals in marine organisms. As a result of the contamination from industrial wastage and domestic discharges from urbanized areas, marine organisms, including molluscs, reflect the rising level of environmental pollution. This study aimed to gather information on environmental contamination in different aquatic organisms and molluscs. Despite their potential as bioindicators for heavy metal pollution in aquatic organisms, there needs to be more research on nutritional composition and bioaccumulation in molluscs.