Heavy metal contamination

This study investigated the levels of cadmium (Cd) and zinc (Zn) in cow offal (shaki, liver and kidney) consumed within Benin City to assess potential human health risks associated with its exposure. Samples of liver, kidney, and intestine were collected from three different abattoirs (University of Benin abattoir, University of Benin Teaching Hospital (UBTH) abattoir and Ekosodin abattoir) and analyzed using an Atomic Absorption Spectrophotometer (AAS) to determine the heavy metal concentrations. Results showed cadmium levels ranging below detectable limits to 1.00 mg/kg was obtained for the duration of the sampling campaign with the highest concentration obtained in Ekosodin market and University of Benin abattoir. Also noteworthy is that cadmium was detected in 25% of all the samples collected. The concentration obtained in this study was found to exceed the Codex Alimentarius limits of 0.5 mg/kg in liver and 1.0 mg/kg in kidney. Zinc concentrations, though essential, were also found in higher than recommended amounts, suggesting contamination from feed or environmental sources. A zinc concentration range of 47 to 197 mg/kg was obtained with the highest concentration obtained in kidney sample from Ekosodin market with a concentration of 197mg/kg while the lowest concentration of 47 mg/kg was obtained in intestine sample from University of Benin Teaching Hospital abattoir. The elevated metal content reported poses potential health risks, especially for vulnerable groups such as pregnant women, children, and the elderly. The findings highlight the need for continuous monitoring of slaughterhouse practices, feed sources, and environmental pollution. Increased public awareness and enforcement of food safety regulations are essential to minimize exposure and protect public health

Soil, surface water and groundwater samples were collected for physico-chemical, microbial and heavy metal analysis from different locations in Ologbo and environs. Thirteen (13) soil samples including Three controls (Pristine environment) were randomly collected at subsurface depth of 0-30cm, Thirteen surface water samples were collected including three controls and Ten (10) Groundwater samples were collected using random sampling Technique. The samples were collected in order to evaluate the level of pollution/Contamination of the media as a result of petroleum activities, wood industries and other anthropogenic activities within the study area. The results for the groundwater analysis showed pH (5.61-5-78), EC (54.64-65.74), Turbidity (0.05-0.12NTU), Cu (0.38-0.49mg/l), Zn (0.3-0.39mg/l), Cr (0.09-0.16mg/l), Ni (0.64-0.85mg/l), Fe (0.38 2.49mg/l), Mn (0.1-0.15mg/l and Pb (0.01-0.16mg/l). The results for the surface water showed pH (5.71-6.05), turbidity (7.31-13.92NTU), EC (87.11-95.2uS/cm), Zn (0.41-0.45mg/l), Fe (1.24-1.3mg/l), Cu (0.51-0.54mg/l), Cr (0.35-0.38mg/l), Ni (0.09-0.21mg/l) and Pb (0.02- 0.06). These results were compared with world and national standards, and control samples were
collected and used for comparison where needed .The result, of the analyses were further subjected to statistical treatment such as Spearman’s correlation Co-efficient, ANOVA and concentration Factor Analysis, to ultimately ascertain the spatial relationship between sample. The ANOVA results for soil samples indicated a very strong significant difference at (p<0.01)
between control and soil samples for all parameters. Correlation results revealed positive and negative correlation Co-efficient at r (0.01) and r (0.05) indicating strong relationship between them, which probably reflects their source of Contamination. Concentration maps generated for the area showed high concentrations of Lead, Copper and Iron around the central area, increasing towards the southwestern part of the maps. The groundwater flow map showed a 2-way flow direction towards the central part where the major river dividing the map is located. The overall results revealed moderate contamination/pollution of all varieties of samples analyzed and it’s here by recommended that important steps be taken to minimize the negative effects of oil exploration and wood industries in Ologbo.