Highlights The use of organochlorine pesticides (OCPs) has caused several devastating health and ecological challenges; one of such includes the sharp decline in amphibian population. Toad’s relatively higher skin permeability afford them a distinguished chemical accumulation tendency compared to other aquatic fauna. The parasite- Cosmocerca sp. has been shown to be a possible bioindicator of OCP congeners as it bioaccumulated OCP congeners from the liver and the intestine. The toads may have been exposed to toxic levels of these chemicals but the parasite- Cosmocerca sp. has demonstrated a novel niche in protecting the host .

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The poor geology of Sangayan Diriya village has barred residents from getting access to water from the groundwater in their homes from time immemorial. This study was aimed at assessing the quality of boreholes sunk in close proximity to River Diriya wherein eight water samples were aseptically collected from the two available boreholes; borehole A (BA1, BA2, BA3 and BA4) and borehole B (BB1, BB2, BB3 and BB4). Standard procedures were employed for determining physicochemical properties, while pour plate method and most probable number (MPN) were used to estimate total viable bacterial counts and coliform count in the water collected, respectively. Results were compared with World Health Organization (WHO) guidelines and Nigerian Standard for Drinking Water Quality (NSDWQ) permissible standards. Results indicated pH, temperature, total hardness, turbidity, electrical conductivity (EC), sulphate, nitrate, alkalinity, calcium, magnesium and nitrate conformed to regulated standards, but mean phosphate concentration (1.79 mg/L) was above WHO allowable limit. However, out of the six heavy metals estimated in the water samples, i.e., Cadmium, Iron, Copper, Arsenic, Lead and Chromium, mean Iron concentration (1.16 mg/L) and mean Arsenic concentration (0.37 mg/L) were above allowable limits. The highest total viable bacterial count (6.3 × 104 CFU/mL) was recorded in BA2. Using the MPN method, BA4 recorded the highest coliform count (14 MPN/100 mL) while BB2 recorded the lowest coliform count (7 MPN/100 mL) each above WHO allowable limit. The findings in this study indicated that the water samples did not meet regulated standards and should be subjected to suitable treatment before drinking.

Plastic are emerging pollutants requiring urgent intervention for its management. In African countries like Nigeria, the evidence to inform plastic pollution management is scanty. This rapid review aimed to systematically evaluate evidence on the distribution, sources, biological effects, research gaps and policy needs of plastic pollution in various environmental matrices in Nigeria. Peer-reviewed journal articles on nano-, micro-, meso- and macroplastics contamination of water, sediment, air, soil and biota were accessed from PubMed, Google Scholar and Science Direct. They were screened, comprehensively revised and critically appraised for inclusion, data extraction and evidence synthesis. A total of 358,974 articles were accessed from any publication date up till May 30, 2021. Only 34 articles met the inclusion criteria and critical appraisal. Only 26 of the included studies reported the distribution, levels and/or effects of microplastics (MPs) (n = 12), macroplastics (n = 12) or both (n = 2) in water, sediment, biota, food and/or land. Only 15 of the 36 states and the Federal Capital Territory had any data on micro- and/or macroplastics. Macroplastics from land-based sources were mainly reported from educational institutions, residential areas and markets. Plastic sources reported were tire wear, cigarette butts, fishing ropes and gears, plastic bags, water sachets and e-wastes. Biological effects (oxidative stress, neurotoxicity, reduced plant root biomass) of virgin MPs were reported in crab, African catfish and lime tree only in laboratory experiments. Microplastic data in biota were limited to selected fish species, aquatic insects and gastropods. Only one (1) study on plastics in waterbodies in Northern Nigeria (Kogi State) was found. Research gaps on plastic distribution in terrestrial biota, other aquatic biota, soil, air, ground and potable water sources as well as biological effects were identified. Policy needs for plastic pollution management identified include stakeholder education, polymer replacement, recycling, tax and incentives to support the sustainability of life below water and on land (UN SDGs 14 and 15).

Bioenhancement of hydrocarbonoclastic microorganisms with suitable nutrients has a huge impact in achieving positive bioremediation of polluted environments. This study was conducted to assess the bio-enhancing effect of some organic amendments on Streptococcus pyogenes and Enterococcus faecalis co-culture with a view to remediating spent engine oil (SEO) contaminated soil. Top soil (1.5 kg) was autoclaved and thereafter contaminated with SEO at three levels. The contaminated soil was inoculated with bacterial co-culture (150 mL) and subsequently bioenhanced with compost, processed cocoa pod husk (CPH) and cow dung. The factorial experiment was laid out in completely randomized design. Concentrations of total petroleum hydrocarbon (TPH) and selected polycyclic aromatic hydrocarbons (PAH) were estimated on the first day, 5th week and 10th week of incubation. Results obtained show that bacterial co-culture bioenhanced with compost produced the most significant TPH reductions (1318 and 261 mg kg-1) on 10% SEO contaminated soil at the 5th and 10th week respectively (p<0.05). Again, bacterial co-culture bioenhanced with compost produced the most significant PAH reductions (65.9 and 55.8 mg kg-1) on 10% SEO contaminated soil at the 5th and 10th week respectively (p<0.05). The significant bioremediation capabilities exhibited by the bacterial co-culture bioenhanced with organic amendments in this study has made these bioremediation agents potential candidates in remediating soils impacted with petroleum hydrocarbons.