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Agricultural and domestic activities around dams in Nigeria involve the use of agrochemicals and insecticides to boost production and combat insect pests respectively. The study aimed to ascertain metals contents and assess the hazards associated with heavy metals in Oreochromis niloticus in three major dams in Ekiti State. Fish samples were collected for 24 months. Metal concentrations in fish samples were determined using spectrometry. The metals concentrations in the tissues were at lower concentrations compared to the maximum acceptable limits in food by Food and Agricultural Organization (FAO) and World Health Organization (WHO). Metals accumulation pattern revealed that the accumulation of the essential metals were higher than those of the non-essential metals in the fish tissues. There were significant seasonal variations in the concentrations of metal in fish tissues within the dam and among the dams. Significant relationships existed at P < 0.05 or P < 0.01 between some of the metals and the fish body weight and body length in the different dams while in others the relationships were not significant. Human health risk assessment showed no significant non-carcinogenic adverse health risk. Carcinogenic health assessment indicates that the utilization of the species as a protein source does not currently pose public health risk to consumers. However, the discovery of cadmium and lead in fish muscle is of great concern because of their toxic effects on human. Therefore, there is a need for close monitoring of these toxic metals contamination to prevent their excessive accumulation in the human food chain.

Water is indispensable to life. Consequently, water and sediment contamination poses severe ecological threats to life. Thus, this investigation aimed to evaluate metal deposition in the sediments and surface water in Ekiti State's three dams and to analyze its potential ecological effects on man's bodily, social, and mental well-being. Metal levels in sediments and dam water were determined using Atomic Absorption Spectroscopy (AAS). Average values of the metals in Egbe, Ero, and Ureje dams, except for K, Mn, and Pb (in Ureje dam), were lower than the acceptable boundaries of local and foreign establishments. The values of the risk quotient (HQ) on the skin and consumption contacts with all metals (except Mn for ingestion exposure for children) were less than one in the Egbe, Ero, and Ureje dams for both adults and children. Consumption HQ values were higher than skin HQ values in the three dams for children and grown-ups. The total hazard index (HI) posed adverse non-carcinogenic risk to children in the catchment area of the dams while the adults were not affected by the non-carcinogenic hazard. The highest cancer hazard was found in the Ureje dam, while the lowest was in the Ero dam. Further, adults were prone to higher cancer risk than children. Using multiple pollution indices revealed that the sediments in Egbe, Ero, and Ureje dams were less contaminated by harmful metals in dry and wet periods. There is a need to reduce current polluting anthropogenic activities around the dams.

Hyptis suaveolens L. is a medical and food plant that is commonly used to treat various microbial infections in humans in many countries of the world. We aimed to study the aqueous and ethanol extracts of H. suaveolens leaves to determine their antibacterial, in-vitro antioxidant, and phytochemical potentials for traditional medicine by using chemical analysis. The aqueous and ethanol extracts inhibited the tested bacteria species with zones of 0–15 and 10–29 mm, respectively. On the typed culture isolates, the inhibition zones were 8–25 and 16–32 mm for the aqueous and ethanol extracts, respectively. The minimum inhibitory concentrations of the aqueous and ethanol extracts were not different, while the minimum bactericidal concentrations for the aqueous extract was higher than that for the ethanol extract. The screened phytochemicals were qualitatively and quantitatively present in both extracts, except for saponins which were absent in the aqueous extract. The free radical scavenging activity in the aqueous and ethanol extracts was 1.44 ± 0.50 and 1.57 ± 1.40 mg of ascorbic acid/1 g dry leaves, respectively. The ferric reduction was 1.19 ± 0.40 and 1.69 ± 0.18 mg of ascorbic acid/1 g dry leaves in the aqueous and ethanol extracts, respectively. Hydroxyl scavenging was 65.0 ± 0.9 and 0.43 ± 0.50 mg of ascorbic acid/1 g dry leaves for the aqueous and ethanol extracts, respectively. The present research suggests that the extract of H. suaveleons can be applied as a controlling antibacterial growth agent against Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Streptococcus pneumoniae and other bacterial pathogens. It is noteworthy that the ethanol extract was more effective than the aqueous one in terms of the antibacterial, phytochemical and antioxidant activities.

Fishes are world widely consumed by all categories of works of life because of their richness in protein, readily available and affordable by all. The basic nutrient of protein in fish that is so important in man’s diet also attracted microorganisms for their growth and multiplication. Meanwhile, the association of microorganisms in fishes depend on the environment of culture and their proliferation due to inadequate storage facilities. The aim of this study was focused on the isolation and identification of microorganisms from four frozen fish species sold in the Ado Ekiti metropolis. Frozen fish samples of Scomber scombrus (Atlantic Mackerel), Clupea harengus (Atlantic herring), Urophycis tenuis (White hake or mud hake) and Trachurus trachurus (Atlantic horse mackerel) from two markets in Ado Ekiti were microbiologically analyzed for possible microbial contamination. On the fish samples, the total heterotrophic count (THC) was 3.5×104 – 5.6×104 CFU/g, total coliform count (TCC) was 2.4×104 – 5.1×104 CFU/g, total Salmonella/Shigella count (TSSC) was 1.3×104 – 3.5×104 CFU/g, total Vibrio count (TVC) was 1.1×104 – 2.3×104 CFU/g and total fungal count (TFC) was 1.3×103 – 2.3×103 Spore/g were analyzed by cultural methods. There were variations in microbial loads among the fish species in the surveyed markets. The microorganisms identified with their percentage occurrence were Bacillus cereus (11.54%), Streptococcus faecium (13.46%), Alcaligenes faecalis (5.77%), Salmonella enterica serovar Typhi (5.77%), Micrococcus luteus (9.62%), Vibrio cholerae (7.69%), Aerococcus viridans (3.85%), Pseudomonas aeruginosa (7.69%), Xanthomonas fragariae (7.69%), Staphylococcus aureus (11.54%), Clostridium butyricum (7.68%), Escherichia coli (7.69%), Aspergillus fumigatus (11.11%), Aspergillus flavus (24.44%), Aspergillus clavatus (8.89%), Aspergillus fishcheri (6.69%), Aspergillus terreus (8.89%), Mucor mucedo (17.78%), Penicillium digitatum (13.33%) and Aspergillus parasiticus (8.89%). The results emphasized the microbial contamination of the fishes. The results obtained could serve as an awareness to consumers that microbial infection is possible from frozen fishes and as data for future reference in epidemiology or outbreak of disease from eating frozen fish.