No abstract

Biosorption remains one of the most productive and safe technologies that could be received particularly with green algae as biosorbent in the ejection of heavy metals from the effluent. Bimetallic nanoparticles were synthesized from Eichorniacrassipies utilizing the mix of both gold chloride and silver nitrate (3:1). Ultraviolet–visible spectroscopy (UV–vis), Scanning Electron Microscopy (SEM), Infrared Spectroscopy (FTIR) and Infrared Spectroscopy (FTIR) were used in the evaluation of the Nanoparticles. The bimetallic nanoparticles wereutilized as a biosorbent for particular heavy metals (lead, zinc, copper and manganese) present in a pharmaceutical effluent. The nanoparticles were brought into the effluent at various concentrations (1mg, 5mg and 10mg) and time intervals of 24h, 48h and 72h. The decrease in concentration of each metal was determined utilizing Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES). The synthesis of NPs was affirmed by colour change in the blend from light green to lilac after 5min of incubation. The UV-visible spectroscopy adsorption spectrum for bimetallic nanoparticles of E.crassipes (EC-AuAgNPs) was at 398nm while SEM micrograph shown spherical and cube shaped particles with size ranging from 0.31nm- 1.077nm. The FTIR absorbance peaks were available at 3263.93 (O-H), 2107.11 (-C≡C-), 1631.16 (C═C), 1338 (C-N), and 1034.96 cm−1 (C-O). The most extreme rate decrease acquired for each metal was; Copper (67.25%, 10 mg at 72 h); Zinc (61.13%, 1mg at 72 h); Lead (93.37%, 1 mg at 72 h) and Manganese (69.26, 10 mg at 72 h).The biosorption of heavy metals by EC-AuAgNPs was contact time dependent for all the metals and biosorbent concentration dependent for only copper and manganese.

The indiscriminate release of untreated or poorly treated effluent from industries into the environment is one of major challenge of industrialization. Heavy metals remain of the components of these effluent that has a deleterious effect on both aquatic lives and man who directly or indirectly depends on the aquatic system for survival. The persistent and non-biodegradable nature of heavy metals has required extended attention to materials that have the ability to remove the non-biodegradable metals by adsorption. The potential of Eichorniacrassipes as an adsorbent in removing heavy metals present in pharmaceutical effluent was investigated. The adsorbentwas introduced to the effluent under different concentrations (1, 5 and 10 mg) and contact time (24, 48 and 72 h). The concentration of Manganese, Copper, Lead and Zinc before and after the experiment was measured using Induced Coupled Plasma –Mass Spectrophotometer. The percentage reduction in concentration of each metal was calculated, for manganese, the highest percentage reduction of 61.86 % (1 mg at 24 h), 63.09 % (1 mg at 24 h), 38.99 % (1 mg, 72 h) and 93.37% (10 mg, 48 h) was reported for Manganese, Zinc, Copper and Lead respectively. This work has presented Eichornia crassipiesas a potential adsorbent with high heavy metal removal efficiency.

Urbanization and industrialization have significantly caused deterioration of surface waters. Since there is close association between river quality and its associated floodplain, the later could therefore provide a quality index of the former. This study examines heavy metal concentrations in floodplain sediment of urban catchment of Asa River and assessed associated risks. Samples were collected at 10 points but at interval of 5cm in vertical profile to a depth of 15cm. Atomic Absorption Spectrophotometer (AAS) analyses were done for Pb, Ni, Zn, Fe, Cu and Al. The following computational models were employed for risk analysis; Depth Ratio (DR), Contamination Factor (CF), Degree of Contamination (Cdeg), Geoaccumulation Index (Igeo), Pollution Load Index (PLI), Hazard Quotient (HQ), Hazard Index (HI) and Cancer Risk Index (CRI). Considerable degree of metal contamination was observed with various pollution levels from non-pollution with Ni, through moderate pollution with Pb, to a moderately strong pollution with Zn, Fe, Cu and Al. PLI revealed a baseline pollution level (PL ≈ 1) but contamination factor for each of Zn, Fe and Cu was considerable and may pose ecological threats and by extension, human health. Metal association reveals a positive correlation among all the metals evaluated (p < 0.05) which is suggestive of similar source. HQ via ingestion and dermal routes calculated were > 1 for both children and adult but< 1via inhalation. CRI for lead shows that children arepredisposed to cancer risks than adults. Hence, industrial activities in the urban catchment of Asa River must be monitored for environmental compliance.

This paper analyzed the effect of flood and socio-economic problems on fish farming in Ibadan Metropolis, Oyo State, Nigeria.A multistage random sampling technique was used to select 80 fish farmers in the state. Both primary and secondary data were collected and analyzed using descriptive statistics to analyze the socio-economic characteristics of the fish farmers, cost and returns analysis was done to determine the profitability ratios of the fish farming in the study areas. The mean age analyzed was 45%. The result of the cost and returns analysis showed that Average Total Cost (ATC) of N1, 500,517.5 was incurred, Total Revenue (TR) of N, 138,659,400 was realized and a returning Gross Margin (GM) of N was 64,885,800 by fish farmers. The major constraints encountered by fish farmers were flooding that wash away fish, deposit heavy metals such as ammonia (NH4), lead, copper, cadmium, arsenic, etc., that can result to the death of fish in the fishponds and rivers when flood overflowing. The methodology applied for the flood examination includes site visits, interviews of affected fish farmers, and analyses of flood data collected during the field examination.