The concentration of respirable dust at seven sampling stations in Jos metropolitan area, was measured weekly for three consecutive months (October 2012 to December 2012). Characterization of the dust particles shows that the concentration of fine dust (<2.5 µm) ranged from 55.0-124.9 µg/m 3 while the coarse dust (2.5-10 µm) varied from 20.0-124.4 µg/m 3. FAAS analysis of the respirable dust shows that the concentrations of heavy metals ranged from 0.121-0.832 mg/kg Pb, 0.019-0.111 mg/kg Cr, 0.171-1.081 mg/kg Fe, 0.002-0.056 mg/kg Mn, 0.002-0.438 mg/kg Cd, 0.696-1.712 mg/kg Zn, 0.025-0.571 mg/kg Cu, and 0.021-0. 478 mg/kg Ni, across the sites studied. The main sources of these heavy metals in the sampled area could be attributed to anthropogenic activities like open incineration of waste and vehicular traffic. The concentrations of Cd, Mn and Ni were found to be far above the standard limits prescribed by the WHO for respirable dust. These results convey the health risk the inhabitants in the study area are exposed to. We therefore recommend that measures be taken to regulate these anthropogenic activities

The water range from Pb (1.439 – 1.715), Cu (0.234 – 0.377), Cd (0.838 – 1.346), Zn (0.448 – 1.110), Cr (0.144 – 0.794), Mn (0.777 – 2.011) and As (0.584 – 1.341) mg/L.  The range in soil was Pb (67.5 – 120), Cu (8.51 – 32.5), Cd (0.21 – 1.72), Zn (70.8 – 85.6), Cr (15.8 – 29.5), Mn (14.6 – 19.1) and As (52.0 – 198) mg/kg and  in the vegetables in the range of Pb (0.177 – 0.545), Cu (0.073 – 0.748), Cd (0.005 – 0.019), Zn (0.264 – 0.915), Cr (0.089 – 0.158), Mn (0.162 – 0.253) and As (0.032 – 0.245) mg/kg. The study shows that the transfer coefficient of the heavy metals to vegetable was less than one (< 1). The estimated daily intake (DIM) of heavy metals from vegetables irrigated with tin mine pond water were in the order: Cd > Zn > Mn > Cr > Cu > Pb > As.  The health risk index (HRI) of all the studied heavy metals indicated that all vegetables were safe with no risk to human health except for Cd.  health risk assessment of heavy metals in consumption of vegetables irrigated with tin mine pond water in Jos - South, Plateau State

The concentration of heavy metals in respiration dust (˂10µg) within Jos Metropolis was monitored in seven sites made up of two industrial and high traffic areas each, with residential site as control were studied for nine consecutive months (October, 2013 to June, 2014). The concentrations of the heavy metals were studied in terms dust mass, time dependence and safety. The mass of respirable dust ranged from 0.079-0.288g, while the mean concentration ranged from 49-208ug/m 3. Flame Atomic Absorption Spectrometry (FAAS) analysis shows that the concentrations of heavy metals ranged from Pb, (0.016-0.331) mg/kg, Cr, (0.016-0.118)mg/kg Fe, (0.012-0.652) mg/kg, (0.07-0.056) mg/kg, Cd, (0.002-0.107)mg/kg, Zn, (0.0233-0.988) mg/kg, Cu, (0.023-0.668) mg/kg and Ni (0.004-0,058) mg/kg across sites studied. The data obtained were treated statistically using one-way analysis of variance at 95% confidence limit for mean and correlated with the anthropological and industrial activities of the sites. The main sources of these heavy metals in the sampled areas, was attributed to anthropogenic activities like open incineration of waste, vehicular traffic and ongoing construction work within some of the sites.

No abstract

The present work was conducted by monitoring the water from twelve major tin mine ponds water in Plateau State, North Central Nigeria (Bokkos, Barkin – Ladi and Jos – South) used for irrigation. Their quality was assessed in terms of physico-chemical parameters for dry and rainy seasons. The physico-chemical parameters such as; Turbidity, pH, Temperature, Electrical Conductivity (EC), Cation Exchange Capacity (CEC), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Total alkalinity (TA), Total Hardness (TH), Dissolved Oxygen (DO), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Phosphate (PO43-), Sulphate (SO42-), Chloride (Cl- ), Fluoride (F-), Sodium (Na+) and Potassium (K+)  were investigated to ascertain the water quality for irrigation purposes. Water quality parameters with regards to its use for the purpose of irrigation such as FAO/WHO/FEPA standards satisfy the requirement for use in agriculture. However, turbidity which ranged from18.1 – 27.4 and 15.9 – 18.8, dissolved oxygen 20.9 – 26.3 and 20.2 – 27.4 mg/L, Total alkalinity 101 – 134 and 122 – 167mg/L, total phosphate 6.3 – 8.9 and 6.5 – 10.5 mg/L, BOD 7.4 – 23.8 and 7.2 – 29.2 mg/L, potassium 1.13 – 1.18 and 3.81 – 4.63 mg/L both in dry and rainy seasons, respectively were found to be above the irrigation water standard limits. The study therefore recommends that the mining pond water should be used with caution as some of the parameters are liable to be toxic to the irrigated crops. The positive correlation exhibited among some of the parameters examined is a clear indication of a common relationship between these sources of water.