Phthalate esters (PAEs) and polybrominated diphenyl ethers (PBDEs) are emerging contaminants whose bioaccumulative potential pose serious risks to ecosystems and human health. This study assessed the concentrations, distribution, and ecological risks of PAE and PBDE congeners in surface water and sediment from four selected catchments along the Lagos Lagoon, Nigeria. Extraction of target compounds was performed using liquid–liquid and ultrasonication techniques, followed by gas chromatography mass spectrometry (GC–MS) analysis. All examined PBDE congeners and two of the six targeted PAEs, di-sec-butyl phthalate (DSBP) and benzyl butyl phthalate (BBP) were detected in all sampling locations and matrices. In contrast, diethyl phthalate (DEP) and phthalic acid decyl hept-2-yl ester (PADHE) was detected in few sites. Mean concentrations of PAEs ranged from 0.39–0.52 mg/L in surface water and 0.33–0.57 mg/kg in sediment, while mean PBDE concentration ranged from 0.047–0.11 mg/L and 0.06–0.21 mg/kg in surface water and sediment, respectively. Benzyl butyl phthalate contributed 73.48% of total PAEs in surface water and 73.07% in sediment, whereas 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153) accounted for 55.14% of total PBDEs in surface water and 34.75% in sediment. Principal component analysis (PCA) revealed a dominance of low molecular weight PAEs: dimethyl phthalate (DMP) and high-brominated PBDEs commonly linked to domestic effluents, urban runoff, plastic based materials, and consumer products indicating intense human activities especially at Makoko and Atlas Cove. Risk quotient (RQ) indicates low risk (RQ < 1) from DEP and DMP, whereas levels of BBP suggest the potential for significant ecological risk (RQ > 100), especially on algae in most locations. Detected PBDE concentrations with RQs ≥ 100, likely resulting from the debromination of heavily brominated deca-BDEs, suggest considerable risk to aquatic biota. Notably, the elevated levels of hexa- and hepta-BDE congeners at Makoko and Atlas Cove indicate potential adverse effects on aquatic organisms. These findings highlight the need for stringent regulatory measures and informed management actions, to safeguard Nigeria’s coastal environments and public health.

The maritime transport sector is a cornerstone of national and global logistics, facilitating the movement of goods and passengers across inland waterways. In Nigeria, the Lagos Lagoon hosts thousands of diesel-powered marine vessels including passenger ferries, cargo barges, and fishing boats, which emit substantial quantities of carbon dioxide (CO₂), contributing to climate change and local air pollution. Waste heat recovery (WHR) via exhaust gas economizers (EGE) presents a cost-effective approach to improving energy efficiency and reducing emissions in these vessels. This study assesses the potential of EGEs as a waste heat recovery solution for diesel-powered marine vessels operating in Lagos Lagoon. Using standard emission factors and thermodynamic calculations, the fuel consumption, CO₂ emissions, available exhaust heat, recoverable heat, fuel savings, and emission reductions are quantified for three representative vessel categories: Passenger Ferry (A), Cargo Barge (B), and Fishing Boat (C). Results show that with an economizer effectiveness of 70%, recoverable heat amounts to 3,586.8, 1,694.8, and 789.1 MJ/day respectively. Equivalent fuel savings are 93.33, 44.10, and 20.53 kg/day, with corresponding CO₂ reductions of 299.23, 141.38, and 65.83 kg/day. These findings demonstrate that EGE-based WHR systems can achieve meaningful emission reductions and operational cost savings in inland waterway vessels. Recommendations for practical adoption are provided, including simplified system designs, stakeholder collaboration, and supportive policy frameworks.

Coastal lagoons, such as the Lagos Lagoon, are ecologically significant ecosystems that are becoming increasingly vulnerable to human-induced stresses, such as urbanization, pollution, and industrial activity. This study evaluated macroinvertebrate compositions and ecological quality status of the Lagos Lagoon using the AZTI Marine Biotic Index (AMBI) to assess responses to these perturbations. Ten (10) stations were sampled across the Lagoon during both dry and wet seasons. Water and sediment samples were obtained using bottom water samplers and a Van Veen grab respectively, and analyzed for physicochemical parameters and macroinvertebrate compositions using standard techniques. Analysis of variance showed significant seasonal changes (p < 0.05) in water temperature, dissolved oxygen, salinity, conductivity, and total dissolved solids. Ten (10) taxa (abundance: 237 individuals) were recorded during the wet season and 9 taxa (abundance: 226 individuals) in the dry season. These taxa belonged to three phyla: Mollusca, Arthropoda, and Annelida. The Shannon-Wiener diversity index ranged from 0.77 to 1.91 (wet season) and 0 to 1.21 (dry season), suggesting low diversity. Simpson's dominance index ranged from 0.60 to 0.86 (wet season) and 0.08 to 0.74 (dry season). AMBI revealed a slight level of ecological disturbance across all Stations, except Stations 6 and 7, with moderate disturbance in both seasons. The findings improved the understanding of the impact of numerous stresses on benthic macroinvertebrate ecosystems and illustrated the usefulness of biotic indices in ecological assessments.

This study assessed heavy metal concentration, bioaccumulation and dietary health risk of Mudskippers (Periophtalmus papilio) from University of Lagos lagoon with a view to determine the consumption safety of the organism. Periophtalmus papilio, Water and sediment samples were collected from two sampling sites each in University of Lagos lagoon front (ST1 and ST2) and Iwaya (ST3 and ST4) bi-weekly for a 2-month period (August - September). The selected physico-chemical parameters of the sediment and water samples from the study areas were determined ex-situ under standard procedure and in-situ with Horiba meter respectively while the heavy metal contents (Cd, As, Mn, Zn, Pb) in the sediments and tissue of P. papilio were analyzed using Atomic Absorption Spectrophotometry. Bioaccumulation factor and dietary risk were estimated using standard models. The result of the study showed that physico-chemical parameters in water and sediment varied significantly across stations (p < 0.05) while the dissolved oxygen of water sample from Iwaya (ST3 and ST4) fell below WHO limits (< 5.0 mg/ L) among all the analyzed physicochemical parameters. Analysis of heavy metals across the stations showed that manganese Mn and zinc Zn at ST3 and ST4 were the only metals that exceeded the WHO/FEPA (2003) permissible limits of 0.5 mg/L and 30 mg/L, respectively. Bioaccumulation factor indicated that Cd in the mudskippers from ST1 was found to be above the threshold of 1.0. The Mean Daily Dose (MDD), Target Hazard Quotient (THQ), Hazard Index (HI), and Target Cancer Risk (TCR) values were below references indicating non-carcinogenic health risks. The study concluded that despite elevated cadmium accumulation in ST1 mudskippers, concentrations of heavy metal detected in sediment and mudskipper (Periophthalmus papilio) from the study area posed no carcinogenic health risks. However, adequate management and legislation are needed to prevent significant heavy metal release into the environment.

ABSTRACT The article addresses entangled scales and environmental enmeshment in the 21st-century Anglosphere, with a focus on the novel Water Baby (2014) by contemporary Nigerian writer Chioma Okereke, read through the methodological lens of new materialism (Neimanis, Armiero, DeLoughrey) and decolonial critique (Mbembe, Nixon, Newell). The analysis situates Makoko – a floating, unmapped and neglected settlement on the Lagos lagoon – as a site where the asymmetries of the contemporary Anglosphere and its crises become starkly visible. Scales and enmeshment are approached through representations of water and the poetics of water (Mentz, Oppermann), as both a constitutive of the human body and the bodies of nonhuman others, as well as the environment that is both agential and precarious. This methodology allows to examine the interplay of scales in the postcolony, manifesting itself in the temporalities of place, multiscalar inequalities and neocolonial infrastructures producing “wasted” lives and places, exposures and vulnerabilities. Through its immersive portrayal of watery materiality, Water Baby reveals how vulnerability is produced across temporal and spatial scales. Drawing on the example of this recent African novel, I show how foregrounding “wasted” bodies and places alongside forms of communal resilience, rendered through blue poetics and narrative hybridization, expand the representational horizons of contemporary Anglophone fiction.

Coastal mangroves and lagoons frequently receive substantial inputs of polycyclic aromatic hydrocarbons (PAHs) from urban runoff, industrial emissions, and oil spills. This review analyzes PAH accumulation in mangrove and lagoon ecosystems worldwide from 2000 to early 2025, based on over 42 articles published during this period. PAH hotspots were observed in water from the Porto-Novo Lagoon (Benin, 3.88 × 107-1.24 × 108 ng L-1) and in sediments from the Sundarbans mangrove wetland (India and Bangladesh, 4880-20 000 ng g-1). Over the past 25 years, levels of the 16 priority PAHs have increased in the Sundarbans but decreased in Fugong mangrove sediments (China). Source apportionment indicated dominant pyrogenic inputs in Lagos Lagoon (Nigeria) water during both wet and dry seasons, and contributions from diesel exhaust (47.2%), coal combustion (17.4%), and oil spills (35.4%) in Estero de Urías Lagoon (Mexico) sediments. In mangroves of Shenzhen (China) and along the Red Sea coasts of Egypt and Saudi Arabia, PAH concentrations were higher in leaves than in roots or surface sediments, while in Hainan (China), PAHs were also detected in mangrove fruits. In the Bodo mangroves (Nigeria), PAHs were found in tipalia (Tilapia guinensis and Sarotherodon melanotheron) and swimming crabs (Callinectes amnicola). Broader investigations across fish species and mangrove-lagoon food webs are needed. These ecosystems perform crucial ecological and economic functions, including coastal protection, sediment stabilization, and nutrient cycling. This review provides a global synthesis of PAH distribution, sources, and temporal trends, establishing a foundation for future monitoring, risk assessment, environmental policy, and research priorities in organic geochemistry.

Bioaccumulation of Polybrominated Diphenyl Ethers in Tilapia guineensis from Lagos Lagoon, Lagos State, Nigeria

The objective of this paper is to evaluate the biohydrogen production potentials of indigenous green microalgae isolated from parts of the western Lagos lagoon, Nigeria using appropriate standard procedures after culturing. Microalgal samples were cultured at their native salinity of ± 7‰, reflecting the brackish conditions. Data obtained show six strains (Algae 1 Closteriopsis acicularis; Algae 2 Desmodesmus sp; Algae 3 Blue green motile coccoid; Algae 4, Nanachloropsis sp.; Algae 5 Asterarcys sp.; and Chlorella sp.) were isolated and identified morphologically. Among these, Asterarcy sp. (AKM893430.1) was confirmed by molecular techniques. Results show that the six green microalgal strains produced detectable H₂ under sulfur-deprived, anaerobic conditions yielding hydrogen (H₂) concentration (Mean ±SD) ranging from 0.0137 to 0.0211 mg/L for morning samples and 0.0192 to 0.0488 mg/L for night samples respectively. The highest hydrogen yields were at night times from Asterarcys sp. peaking at 0.0488 mg/L. This work marks a pioneering documentation of biophotolysis-driven hydrogen production by live microalgae cells cultured from parts of the Western Lagos Lagoon system, Nigeria, establishing the foundation for tropical bioenergy innovation.

Continuous water quality monitoring remains a potential concern because of its connection to human wellbeing and aquatic ecosystem. This study examines seasonal variation of TSS concentration in Lagos Lagoon surface water. The Lagoon is located in South-west coastal region in Nigeria known to be extremely contaminated because of its vulnerable location, increasing human activities and infestation from nearby creeks. The investigation utilized Landsat 8-9 multispectral spatial bands (OLI & TIR) while band combination indices, such as WRI (Water Ratio Index) and NSMI, (Normalized Sediment Material Index) that used blue, red, green, NIR and SWIR Band was utilized respectively. Automated Water Extraction Index (AWEI) was employed for further confirmation of sediment concentration. Linear and nonlinear regression testing was used to analyse the correlation between the remotely sensed data and the in-suit data. Result revealed modest undesirable correlation between the employed indices and the real time in suit data reflecting non alignment relationship. Nonlinear equation testing reported highest = (0.42) which is slightly stronger than the linear case with highest (0.27). The dry season equally reports considerably more total suspended solids and turbid particles than the wet season. The final outcome effectively proved the capability of Landsat improved sensor bands in retrieving TSS in Lagoon surface water.

Shrimps remain a healthy seafood option found in most recipes of people all over the world due to its rich supply of protein, vitamins and minerals. With this and several reasons, it becomes pertinent for consumers to be informed on the choice of the parts of the shrimps they eat. This study therefore, sought to examined the morphometric characters and the biochemical composition of the whole, flesh and exoskeleton of P. monodon and P. longirostris from Lagos Lagoon. Using standard methods, the species were collected monthly between November, 2022 and February, 2023 and later subjected to various laboratory procedures. The morphometric characters showed that P. monodon is larger than P. longirostris with the total length ranging from 11.00 - 20.00 cm, 8.00 - 14.00 cm, total weight ranged between 9.10 - 30.40 g, 5.70 - 15.50 g (before de-shelling) and 5.60 -15.80 g, 3.20 - 6.00 g (after de-shelling) for P. monodon and P. longirostris respectively. The proximate composition varied significantly (p0.05) in both species for the whole body, flesh and the exoskeleton. The flesh of the species contained the highest amount of moisture (7.91, 7.62 %), crude protein (44.01, 45.63 %) and crude fat (1.12, 1.59 %) while the exoskeleton had the highest amount of crude fibre (0.30, 0.23 %), total ash (36.62, 33.82 %) and total carbohydrate (40.87, 41.20 %) for P. monodon and P. longirostris respectively. The minerals analysis indicated that the exoskeleton of the two species had the highest mineral contents with Calcium been the highest (20.58±0.06 g‎/100g, 18.92±0.11 g‎/100g) of all the minerals for P. monodon and P. longirostris respectively. Based on this nutritional composition, the various parts of both species are recommended for consumption by all human age groups depending on individual preference. The exoskeleton and the shrimp head which are often considered as waste from shrimp processing could serve a potential alternative for industries engaged in animal feed formulation. It is therefore pertinent to pay attention to shrimp nutritional composition which will be of importance to shellfish biologist and aquaculturist during the feed formulation.

Lagoon systems in Nigeria serve as essential ecosystems for fisheries and local livelihoods, yet, they face increasing threats from industrial discharges, agricultural runoff, and urban pollution, which may degrade water quality and pose health risks to coastal communities. This study comparatively assesses how varying anthropogenic activities influence the physicochemical properties and heavy metal levels in surface waters of Nigeria’s interconnected coastal lagoons and also evaluates the contamination indices, pollution sources, and human health risks. The physicochemical parameters were; pH (6.86–6.97), dissolved oxygen (4.39–5.91 mg/L), total suspended solids (20.81–21.74 mg/L), electrical conductivity (26.28–217.11 uS/cm), and total dissolved solids (61.82 mg/L) and were within the recommended limits, except for TDS. The distribution trends and average levels of heavy metals were as follows: Zn (1.98–4.60 mg/L) > Fe (0.59–3.79 mg/L) > Cu (0.18–3.10 mg/L) > Cr (0.02–0.785 mg/L) > Pb (0.30–0.50 mg/L) > Cd (0.15–0.41 mg/L) > As (0.05–0.06 mg/L) > Ni (0.02–0.06 mg/L). Heavy metal concentrations were highest during the dry season, and the spatial analysis revealed that the concentrations of Cd, Pb, and As were highest at stations LE6 and LE9 in Lekki Lagoon, indicating areas primarily influenced by agriculture, tourism, and dredging activities. In Lagos Lagoon, stations LA1, LA3, and LA5 presented the highest levels, mostly contaminated with Cd, Cr, and Pb, corresponding with locations dominated by industrial wastewater discharge, crude oil processing, shipping activities and leaching oil from abandoned power plants. The integrated pollution and water quality indices revealed that approximately 90% of the sampling stations of both lagoons presented moderate to extreme contamination levels, rendering the water unsuitable for drinking, with potential uptake, accumulation, and ecological risks for important ecosystem functions. Multivariate analysis revealed that the elevated heavy metal concentrations in both lagoons originated primarily from diverse anthropogenic activities. The health risk assessment revealed that ingestion of Cd, Cr, and As poses the highest threat to human health, with most of the sampling stations, especially in Lagos Lagoon, presenting potential non-cancer and carcinogenic health risks, with children being the most vulnerable group. Our findings showed that both lagoons are highly contaminated irrespective of the varying anthropogenic influences. Thus, we recommend stringent monitoring of land use and contaminant sources, implementation of targeted remediation at high-risk sites, and development of integrated coastal-zone management strategies to protect the lagoon ecosystems and human health.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-22727-3.

Surface sediments collected from Apapa-Badagry creeks (west of Lagos Lagoon) were investigated for the presence of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs). The total OCP concentrations (∑OCPs) ranged from 231.72 to 1324.57ng/g, while ∑PAHs ranged from 15.17 to 30.92ng/g. Drins were the most prevalent pesticides detected across all sample stations. All low molecular weight (LMW) PAHs were below the detection limits, except for acenaphthylene. Urban runoff and nearby industrial and domestic discharges could be responsible for the high levels of OCPs and PAHs at station L_P2. Isomeric ratio analysis of DDT compounds indicated no recent inputs of technical DDT, whereas hexachlorocyclohexane (HCHs) suggested a lindane source. Diagnostic PAH ratios suggested mixed sources of pollution, which were pyrolytic and petrogenic. Principal component analysis of the OCPs and PAHs dataset extracted three principal factors, each representing distinct pollutant origins within the creek sediments. The sources of OCPs were mainly agricultural and industrial run-off, whereas PAHs were primarily attributed to industrial emissions, biomass and wood burning, and vehicular combustion. Ecological risk assessment indicated that adverse effects from p,p'-DDT would rarely occur, whereas those from p,p'-DDD would occur regularly in benthic organisms in Apapa-Badagry Creek.

The accumulation of mismanaged plastics has continued as a significant threat to the health and ecological functions of coastal ecosystems globally. This study examined microplastic (MP) contamination and ecological risks of twenty-four sediment samples from four locations characterized by significant anthropogenic activities along the Lagos Lagoon. Physicochemical properties of sediment were analyzed using standard methods, while morphological classification of microplastics and polymer identification was carried out using a stereomicroscope and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) following pretreatment with 30% H₂O₂ and density flotation with ZnCl2. Microplastic abundance ranged from 9.17 ± 6.05 to 12.17 ± 7.55 microplastics/kilogram (MPs/kg), while morphological analysis revealed predominance of fibers (41.4%) and black microplastics (49%). Polyethylene terephthalate (PET) was the most abundant polymer in sediments, suggesting indiscriminate disposal of single-use plastic bottles. One-way ANOVA showed no significant differences among sampling locations for pH (F3, 16 = 1.29, p = 0.31), electrical conductivity (F3, 16 = 1.10, p = 0.37), total organic carbon (F3, 16 = 1.10, p = 0.37), or microplastic abundance (F3, 16 = 0.31, p = 0.82), suggesting relatively uniform sediment conditions. The detection of potentially toxic polymers raises concern over long-term ecological risks. The Polymer Risk Index (PRI) indicates varying ecological risk, with level IV (high) and V (very high) as the predominant categories. This suggests the potential for significant adverse effects to aquatic organisms and ecosystem health. The result emphasizes the urgent need for improved waste management practices, stricter regulation of single-use plastics, sustained monitoring and effective mitigation strategies around the Lagoon’s catchments.

Fishery resources in Nigeria are experiencing a rapid decline, underscoring the urgent need for effective biodiversity surveys and comprehensive species documentation to guide conservation and management efforts. However, traditional methods for fish surveys, such as gillnets and trawl surveys, are intrusive, time-intensive, and costly. Environmental DNA (eDNA) metabarcoding has emerged as a non-invasive method for surveying fish diversity, yet its application in Nigerian aquatic ecosystems remains limited. This study evaluated the potential and limitations of 12S rRNA-based eDNA metabarcoding to survey fish communities across three water bodies (Jebba Hydroelectric Power Dam, Asa River, and Lagos lagoon). We also compared fish community composition obtained from our eDNA samples with previously published inventories based on traditional sampling techniques. Our study revealed several advantages of using eDNA metabarcoding for fish biodiversity surveys in Nigeria, including the rapid and non-invasive identification of fish taxa, the detection of differences in community composition and biodiversity metrics, the identification of species overlooked by traditional methods, and the ability to detect both threatened and invasive species. However, we identified three major constraints that must be addressed for the successful integration of eDNA sampling techniques in Nigeria. First are the logistical challenges, including determining the optimal number of replicates, selecting the appropriate water volume per site, determining the required number of sampling sites per study area, and identifying the most suitable time within the season for sampling. Second is the lack of a comprehensive DNA reference database for accurate species identification. Third are the issues with primer and marker specificity. Until a comprehensive regional DNA reference library is developed, suitable molecular markers are optimized, and standardized field protocols for eDNA sampling are established, we recommend using eDNA metabarcoding as a complementary survey tool rather than a replacement for conventional fish survey methods in Nigeria.

Yewa Lagoon, part of the Lagos Lagoon complex on the Guinea coast of West Africa, is subject to intense anthropogenic activity, necessitating regular monitoring of its water chemistry and biological properties. Hence, the objective of this paper was to evaluate the seasonal variation in phytoplankton diversity, distribution, composition and chlorophyll A at Yewa Lagoon, Nigeria using various standard methods, over an 18-month period (August 2017 – January 2019). Monthly sample collections revealed seasonal fluctuations influenced by rainfall and runoff, affecting water quality parameters. Air and water temperatures were high (24.0 – 34.0 °C and 26.5 – 37.5 °C), with salinity ranging from 0.0 – 9.0 ‰ and pH (5.7 – 7.9). Dissolved oxygen (1.0 – 9.6 mg/L) and biochemical oxygen demand (1.1 – 12.3 mg/L) indicated variable pollution levels, with chemical oxygen demand (≤478 mg/L). Chlorophyll A levels (1.04 – 16.8 μg/L) were higher in the dry season. Heavy metal concentrations were low, while nutrient levels (reactive nitrogen, phosphorus, sulphate, and silica) were high. Calcium and magnesium concentrations were higher in the rainy season. Significant differences (p<0.05) across stations were only observed for sulphate and COD in the rainy season, and air temperature and water depth in the dry season. Phytoplankton diversity included 315 species from 112 genera across 11 classes and 7 divisions, with notable taxa such as Microcystis aeruginosa, Nitzschia, Navicula, and Cyclotella. Seasonal changes and pollution affected phytoplankton diversity and abundance. Carlson’s Trophic State Index classified the lagoon as eutrophic (60–80), supported by the dominance of cyanophytes (44%) and diatoms (40%) and low ecological index values (Shannon ≤1.929, Margalef ≤8.436, equitability ≤0.477), indicating moderate biodiversity and potential ecological stress.

From November 2021 to April 2022, a study was carried out to determine the occurrence and distribution of phytoplankton in five locations within the Lagos Lagoon: Oke-Afa, Ago, Festac Creek, Reservoir, and Festac Link Bridge. The objective of this paper was to report a Checklist of occurrence and distribution of phytoplankton species in waters around the Festac creek, Lagos Nigeria using a 55 µm mesh size standard plankton net to collect the phytoplankton sample, dragged for five minutes at a slow speed (≤4 m/s) from a motorized boat and placed in a screw-capped plastic container with a clear label. Microscopic analysis was performed 48 hours after each sample was preserved with 4% unbuffered formalin and kept in the lab. Bacillariophyta, Cyanophyta, Chlorophyta, and Dinoflagellates are the four major groups of algae that were identified. In all, 70 species from 40 genera were identified. With 36 species spread across 22 genera, diatoms were the most prevalent group. Dinoflagellates had eight species from five genera, Chlorophyta has nine species from six genera, and Cyanobacteria has sixteen species from six genera. In contrast to the wet season, a greater number of species were observed during the dry season. The study's conclusions offer helpful details on the list of phytoplankton species that may be employed as bio-indicators for the creek's evaluation and observation.

An updated checklist of fishes occurring in the Nigerian Lagos Lagoon (NLL) is presented, with notes on species additions, nomenclatural revisions, and conservation status.Information was compiled from various sources, including published primary literature and field surveys. Our study takes a cautious approach by omitting previous inventory records without clear species-level identification and records outside the species true geographic range.Of the species previously reported in primary literature, seventeen were geographically misattributed while 11 underwent recent taxonomic revisions. Our field surveys included 39 species, out of which 15 that had not yet been previously reported from NLL which represent new species additions to the inventory. Following the removal of erroneous species records, our study indicated a total of 113 species from 85 genera, 52 families, and 20 orders from NLL. Conservation assessment based on the IUCN Red List indicates that 11 species are assessed as Data Deficient, 91 as Least Concern, five as Near Threatened, five as Vulnerable, and one as Endangered. Our study highlights the rich ichthyofaunal diversity of NLL and underscores the importance of accurate species identification and distribution data for conservation planning. Furthermore, we recommend further studies on various aspects of the fish biology and threats to advance scientific research and develop conservation plans for the fish species of NLL.

The aquacultural potential (such as food and feeding habits) of a fish cannot be thoroughly determined without the knowledge of some aspects of its bioecology. This study investigated aspects of the bioecology of Tarpon, Megalops atlanticus (Valenciennes,1847) in Lagos Lagoon, Lagos, Nigeria. A total of 1,115 fish specimens from three (3) sampling stations A (Igbo Elejo -334), B (Tomaro - 448)) and C (Itan Agan- 333) were collected between January 2016 and April 2018. The study's objectives included assessment of physico-chemical parameters, morphometric characters, food and feeding habits, and reproductive behaviours. Total length and body weight were measured with a standard measuring board and Sartorius weighing balance respectively. Growth patterns, condition factor, length frequency distribution, and gonadosomatic index (GSI) were determined using Standard scientific methods. Sexes were differentiated by both macro and microscopical examinations of the genitals. Feeding habits of the M. atlanticus were determined using frequency of occurrence and numerical methods. The gonadal stages were determined using histological examinations of the gonads. Water parameters (pH, dissolved oxygen, turbidity, salinity, CO2, temperature, total alkalinity, and total hardness) were measured following the American Public Health Association Standard.

S. The spread of impermeable surfaces in urban coastal areas increases runoff, carrying pollutants that degrade surface water quality and impact the stress responses of coastal fauna. This study investigated oxidative stress and gonad health in male and female Callinectes amnicola (blue crabs) from urban and suburban regions of Lagos Lagoon. Gonadal damage in the crabs was linked to estrogenic metals (Cu, Zn, Pb, Cd) and antioxidant responses (MDA, GSH, GPx, CAT, and SOD). Urban male crabs showed higher oxidative stress, with elevated MDA and lower GSH and CAT levels, alongside regressive gonadal changes due to increased Pb, Cd, and Zn exposure. Suburban crabs, however, displayed more intersex conditions (ovotestes) correlated with elevated Cu levels in lagoon sediment. These results highlight severe testicular disruption in urban males and ovarian dysgerminomas in suburban females, indicating a sex-specific impact of pollution on reproductive health. The study identifies two primary reproductive toxicity risks: (1) male testicular damage and regressive lesions in urban crabs, caused by increased lipid peroxidation and oxidative stress, and (2) female endocrine disruption, with ovotestes in suburban populations potentially leading to nonviable follicles. These findings emphasize that urban blue crabs face significant risks across both sexes, while suburban populations are more affected by female-specific risks. The study underscores the need for targeted environmental management to address the different stressors impacting these populations.

The uncontrolled production of waste is a daily phenomenon that is experienced by most global communities, and the situation worsens due to the lack of effective waste management procedures. Solid waste such as sawdust is primarily produced by the forestry industry and although it is utilized by certain countries as briquettes to make fire or as an absorbent to clean fluid spillage as well as a component of ceilings, most of the sawdust along the Lagos Lagoon in Nigeria is left unattended as waste, contributing to environmental pollution. Cellulose, composed of glucose units is a structural component of sawdust and when saccharified the resulting glucose can be fermented into renewable substances such as bio-ethanol. The cellulose degradation process can be performed with a cellulase enzyme such as available in the fungus Aspergillus niger and during the current investigation, this enzyme system was used to bio-convert the cellulose component of sawdust from ten different trees along the Lagoon into glucose. To increase the cellulase action all sawdust materials were delignified before cellulase action with the main aim of determining the optimum pH value for maximum degradation of the various sawdust materials. The pH-related saccharification profile of each type of sawdust was constructed as well as the relative percentage of saccharification and it was concluded that all the materials were optimum degraded at acidic pH-values which varied between pH 5.0 and pH 6.0 that are like optimum pH-values reported for the other types of cellulose materials.