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The gamma dose rates and the activity concentrations of Potassium-40, Uranium-238, and Thorium-232 in the study area were carried out using calibrated hand-held gamma detector, (RS-125 Gamma-Spectrometer) and NaI (Tl) gamma spectroscopy. The in-situ measurements result of dose rate indicates the hotspot at location 4 with a value of 100 nGyh-1, almost twice higher than the recommended limits. The results from NaI (Tl) gamma detector revealed the highest activity concentrations of Potassium-40, Uranium-238, and Thorium-232 to be 288.09, 96.49, 136.12 Bqkg-1 for sediments and 257.31, 66.93, 96.57 Bqkg for water, respectively. The highest mean activity concentration of Potassium-40 and Uranium-238 was observed in Catfish with values of 151.87 and 38.00 Bqkg-1, whereas the highest value for the activity of Thorium-232 was observed in Tilo Fish with a value of 89.02 Bqkg-1. In comparison, all the observed values are higher than the population-weighted average of 420.00, 32.00, and 45.00 Bqkg-1 for Potassium-40, Uranium-238, and Thorium-232 by UNSCEAR. Geologically, this may be attributed to the marine incursion of regional tectonic subsidence during transgression. Statistically, the correlation results confirmed that the enhanced outdoor dose rates at the coastlines environment were caused mainly by Uranium-238, followed by Thorium-232 and then Potassium-40 in magnitude. The mean hazard indices for the samples were observed to be within the world average values recommended by ICRP. The accumulation of radionuclides by fishes may be via ingestion and adsorption to surfaces, which culminate in speciation and mobility of radionuclides, alongside the feeding habits of fishes and other aquatic animals.

Gongronema latifolium Benth., is listed among the important vegetable with medicinal attributes. Its native habitat currently threatened in Nigeria and there is death of molecular genetic information important for breeding and conservation purposes. To study the species genetic diversity, 50 accessions were collected from South Eastern Nigeria where the species is endemic and was subjected to molecular evaluation using the non-coding internal transcribed spacer (ITS 4 and 5) location. Relatively high within population gene diversity and low nucleotide (base) diversity was identified among the fifty (50) accessions. AMOVA analysis highlighted 93% within population diversity (variations). FST = 0.074 genetic differentiation was recorded for genetic diversity. Principle component analysis (PCA) segregated the accessions into four large groups (A-D), along non-geographical lines; with four outliers’ accessions; AwkCH051 (Akwa Ibom), EnuCH014 (Enugu), EboCH036 and EboCH037 (Ebonyi). Expectedly, the species recorded low-moderate genetic diversity common for organisms experiencing decreasing cover range. Enugu recorded the least within population diversity and Ebonyi showed higher diversity than states and might constitute the core of a possible genetic centre for the species. The outlier accessions represent potential parental lines for breeding and improvement programmes. Conservation efforts comprising in situ and ex situ strategies are required to arrest the declining diversity of the species in its native range across Southern Nigeria. Conservation and improvement efforts will sustain the uses of the plants, reduce poverty and improve the livelihood of gatherers, farmers and vendors of the plant, who are particularly women in the region.