Heavy Metal

Epublic Health Significance of Nutrients, Heavy Metal and Total Heterotrophic Bacteria Interaction in Water Bodies in Port Harcourt and Its Environs (Published)

Water is an essential commodity for all living things. It is an inorganic compound that can exist in solid, liquid and gaseous state under normal condition. The quality of any water body depends on certain factors such as the absence and or very neglectable amount of Total Heterotrophic bacteria count, heavy metal including physicochemical parameters among others. This study was carried during the dry season of 2021, and accounts for groundwater, surface and well water in Abuloma, Borikiri, Eagle-Island, Fimie, Macoba-Isaka, Ruekini and Rumuokoro respectively. Water samples were collected in 10ml sterile containers and labeled appropriately. Sample for the River was collected at the pelegial level stoppered while submerged. Sample from the boreholes and hand-dogged wells were collected in line with the American Public Health Association (APHA, 2107). The samples for the determination of heavy metal contents were fixed with 2 drops of concentrated trioxonitrate (V) acid (HNO₃) while that for microbial analysis were preserved in ice chests to inhibit the activity of microbes and were sent to the laboratory for further analysis. Results indicated that the nutrients (NO₃^–, SO₄^3- and PO₄^2-) values appeared insignificant (i.e., values are within the acceptable levels) when compared with European Union guidelines for water consumption except PO₄^2- for well water at Rumuekini and Rumuokoro respectively. The THBC factor was high in Abuloma for all the nutrients in surface water. Also, in well water, at Eagle-Island, Pb appeared elevated above the European Union standard for drinking water quality. Thus, it is recommended that well water from Eagle-Island be treated (i.e., the removal of Pb) to ensure it quality and safety for human consumption.

Keywords: Heavy Metal, Nutrients, Toal heterotrophic bacteria, public health

Environmental Assessment of Heavy Metal Concentrations of Colocasia Esculenta L., Vernonia Amygdalina Del. And Amaranthus Spinosus L. And Soils Collected Around Some Abattoirs in Lagos State, Nigeria (Published)

Wastes from abattoirs may have significant effects on the soil and the surrounding plants in Lagos State of Nigeria where there are poor abattoir practices. Thus, this study aimed at assessing some heavy metals’ concentrations of Colocasia esculenta, Vernonia amygdalina and Amaranthus spinosus and soils collected around some selected abattoirs in Lagos State, Nigeria. Samples of C. esculenta, V. Amygdalina, A. Spinosus and soils were obtained from three different abattoirs in three local government areas of Lagos State. Heavy metal analysis was done on plants and soil samples using standard analytical procedures and mean-standard-deviation were used for analysis. Analysis of heavy metal revealed the concentration range of Lead (Pb) [0.001-0.053mg/100g]; Cadmium (Cd) [0.001-0.008mg/100g]; Manganese (Mn) [0.006-0.053mg/100g]; Cobalt (Co) [0.003-0.007mg/100g], Nickel (Ni) [0.001-0.003mg/100g]; Zinc (Zn) [0.246-0.7441 mg/100g] and Chromium (Cr) value was 0.001mg/100g in three vegetables across the three abattoirs. Also, the soil analysis showed that the concentrations range of Pb [0.110-0.123mg/100g]; Cd [0.017-0.019mg/100g]; Mn [0.340-0.695mg/100g]; Cr [0.001-0.004mg/100g]; Co [0.011-0.013mg/100g]; Ni [0.005-0.006mg/100g] and Zn [1.104-1.267mg/100g]. These metallic concentrations were below or within metallic limits set by World Health Organization and thus, are safe for consumption at time of this study. However, efforts should be made to reduce these metals in order to prevent abattoirs’ effluents accumulation. This study therefore suggest that abattoir effluents should be correctly channelled and controlled into cesspit or treated to avoid plants and surrounding soils’ heavy metal build-up.

Keywords: Abattoir, Colocasia esculenta, Heavy Metal, Vernonia amygdalina Amaranthus spinosus and soils, Waste.

Assessment of Heavy Metals Pollution in Soft Sediment of the Severn Estuary and Inner Bristol Channel System (Published)

For several decades, the Severn Estuary and Bristol Channel have been contaminated by heavy metals despite the many ecosystem services it provides. Therefore, this paper is devoted to the systematic assessment of heavy metals (Cd, Cr, Ni, Zn and Pb) pollution in soft sediments of the Severn Estuary and Inner Bristol Channel. An unpublished 2016 monitoring survey data of the Severn Estuary and Bristol Channel was obtained from the UK Environment Agency to assess seasonal variations, spatial distribution, exceedances, ecological risk, and potential sources of heavy metals. Seasonal variations between the concentration of heavy metals during summer and winter revealed that irrespective of seasons the concentration of heavy metals had the trend Zn > Cr > Pb > Ni > Cd. Concentrations of metals were higher in summer than winter, and there was a significant difference between metals concentration in summer and winter (P < 0.05). Spatial distribution of metals using the Empirical Bayesian Kriging (EBK) model revealed that irrespective of the seasons, concentrations of Cd, Cr, Ni, Zn and Pb in the distinct reaches of the estuary followed the trend Severn middle > Severn lower > Inner Bristol Channel > Severn upper. One-way ANOVA, which was followed by the Tukey’s HSD test, showed a significant difference between the mean concentration of heavy metals in the distinct reaches of the study area at p ≤ 0.05. Assessment of heavy metals using the USEPA Sediment Quality Guideline revealed that none of the reaches of the estuary was polluted with Cd. The Severn upper was not polluted with Pb. The Severn middle was moderately polluted by Ni but heavily polluted with Zn, Cr and Pb. Other reaches of the estuary were moderately polluted with Cr, Ni, Zn and Pb. Assessment of ecological risk of heavy metals using pollution indices such as geo-accumulation index (Igeo), contamination factor (CF), metal pollution index (MPI) and pollution load index (PLI) revealed that heavy metals such as Zn, Pb, Ni and Cr in the distinct reaches of the estuary and might pose an adverse effect on biota and ecosystem services of the Severn Estuary and Inner Bristol Channel. Identification of potential sources of metals using Pearson correlation, hierarchical cluster analysis (HCA) and principal component analysis (PCA) suggested that heavy metals all originated from anthropogenic sources.

Keywords: Heavy Metal, Soft sediment, Spatial Distribution, ecological risk, potential sources, seasonal variations

Comparative Evaluation of Lycopene and Heavy Metal Contents Of Two Species of Tomatoes Within Awka Metropolis (Published)

Tomato Species belong to edible vegetable fruit obtained from tomato plant which serves as a food source to people irrespective of culture, religion and belief. Two species of the tomato samples were bought from five different local markets within Awka metropolis, Anambra State. The samples were washed with deionised water, and lycopene content extracted using solvent mixture of n-hexane, acetone and ethanol in the ratio of 2:1:1 respectively. The extract was subjected to Uv spectrophotometer for lycopene content at 503nm. The moisture content was examined via difference in weight in an oven at 105⁰c. The washed samples were blended and digested with acid mixture of 10ml perchloric acid, 25ml concentrated nitric acid and 4ml sulphuric acid. The level of heavy metal in the digest was evaluated using atomic absorption spectrophotometer. The results showed lycopene range of 18.82mg/kg to 98.52mg/kg. The higher concentration of lycopene was associated with Beefsteak species with average value of 73.13mg/kg, while a lower average level of 40.76mg/kg was implicated in cherry specie. Lead was the metal with lowest average concentration of 0.083ppm. The metal with the highest average concentration in the tomato samples was chromium (0.520ppm). The observed trend in the metal concentration for all the samples was Cr (0.520ppm) > Cu (0.493ppm) > Fe (0.453ppm) > Zn (0.421ppm) > Cd (0.121ppm) > Pb (0.083ppm). Only Pb was within the permissible limit as stipulated by WHO (Pb-0.1mg/L), all other metals were above the permission limit as stated by FAO and WHO of 2011. Expectedly the tomato had high moisture content (95.7%). Statistical treatment of the data showed the existence of a strong inverse correlation between Fe and Pb concentration in the tomato sample (r = -710, p = 0.020). There was no statistical correlation between lycopene content and the total metal concentration (r = -0.349, p = 0.324).

 

Keywords: Heavy Metal, Lycopene, Tomato, Vegetable, fruits and spectrophotometer

Analysis of Heavy Metal Contamination by Artisanal Refining Plants in the Niger Delta Region, Southern Nigeria (Published)

Artisanal refining Plants are common features of the Niger Delta Region of Nigeria. The effects of heavy metal contamination on soil by non-conventional refining plants were investigated and analyzed using standard methods. Two soil samples were collected at 18 m intervals between Plants A and B and at 24 m intervals between Plant B and C. Then control sample was collected 2 km away from unimpacted soil. The result of the analysis showed that polynuclear aromatic hydrocarbon (PAH) recorded maximum concentration of 6899.4942 ppm at station C at the depth of 0-15 cm. Furthermore, the concentration of heavy metals investigated are below critical levels as proposed by FEPA (1991) and NCC(1991).

Keywords: Artisanal Plants, Heavy Metal, Hydrocarbon Contaminated, Niger-Delta, Nigeria