This study compared the physicochemical parameters and heavy metal levels in soil samples from selected anthropogenic sites within Enugu metropolis, Enugu State, Nigeria using standard analytical methods. Soil samples...This study compared the physicochemical parameters and heavy metal levels in soil samples from selected anthropogenic sites within Enugu metropolis, Enugu State, Nigeria using standard analytical methods. Soil samples at depths (0 - 20 cm) and (20 - 40 cm) were collected from waste dump sites, metal scrap dumps, fuel filling stations and auto-mechanic workshops and analyzed for physicochemical characteristics and heavy metal levels. Atomic absorption spectrophotometer was used for heavy metal determination while conventional analytical methods were employed for physicochemical parameters evaluation of the soil samples. At soil depths 0 - 20 cm and 20 - 40 cm the respective mean range of pH, electrical conductivity, organic matter and organic carbon contents in the soil samples were, 6.33 - 6.74, 101.46 - 123.21 <em>μ</em>S/cm, 6.41% - 8.35% and 13.73% - 16.14% for auto-mechanic workshops;6.92 - 7.43, 56.46 - 60.02 <em>μ</em>S/cm, 1.53% - 2.20% and 11.93% - 12.60% for fuel filling stations;7.14 - 7.84, 70.81 - 77.71 <em>μ</em>S/cm, 3.81% - 4.12% and 8.57% - 9.24% for metal scrap dumps;6.54 - 6.81, 94.40 - 100.71 <em>μ</em>S/cm, 8.83% - 10.75% and 18.26% - 20.81% for waste dump sites. The pH of the top soil samples from auto-mechanical workshop was below the WHO recommended limits for agricultural purposes. The physic-chemical characteristics of the soil samples decreased with soil depths indicating therefore that anthropogenic activities greatly influence the soil characteristics at the top soils than the sub-soils. The electrical conductivity values of top and sub-soil samples from the studied auto-mechanical workshops were above the recommended limits. At soil depths 0 - 20 cm and 20 - 40 cm, the respective mean range of Zn, Pb and Cd in the soil samples were 17.29 - 19.16 <em>μ</em>g/g, 0.704 - 0.96 <em>μ</em>g/g and 0.26 - 0.33 <em>μ</em>g/g for auto-mechanic workshops;4.13 - 4.88 <em>μ</em>g/g, 0.21 - 0.32 <em>μ</em>g/g and 0.03 - 0.11 <em>μ</em>g/g for fuel filling stations;30.02 - 36.11 <em>μ</em展开更多
Studies were carried out to determine asbestos fiber levels in cosmetic (talc powder) and non-cosmetic (gauze pad, plastic filler and ceiling tiles) products sold in market outlets within Enugu, metropolis, Enugu Stat...Studies were carried out to determine asbestos fiber levels in cosmetic (talc powder) and non-cosmetic (gauze pad, plastic filler and ceiling tiles) products sold in market outlets within Enugu, metropolis, Enugu State, Nigeria, using standard established procedures. The samples were pretreated based on its physical make-up and the asbestos fiber levels determined using scanning electron microscopy (SEM) with energy dispersing spectroscopy techniques. The mean range of asbestos fiber was, 0.02 - 0.06;0.01 - 0.05;0.01 - 0.04 and 0.03 - 0.06 f/cc for talc powder, gauze pads, plastic filler and ceiling tile samples respectively. The mean levels of asbestos fibers in the studied samples were within the recommended permissible limits. The samples contain asbestos fiber in the following decreasing order: ceiling tiles > talc powders > gauze pads > plastic fillers. Asbestos fiber was found present in the investigated local and foreign items sold in market outlets within the metropolis. This study shows that despite the ban on the use of asbestos in the industry in the manufacture of items meant for human use, its enforcement appears weak and lethargic and this could portend health danger especially in the use of produced items with high asbestos fiber friability such as talc powder.展开更多
文摘This study compared the physicochemical parameters and heavy metal levels in soil samples from selected anthropogenic sites within Enugu metropolis, Enugu State, Nigeria using standard analytical methods. Soil samples at depths (0 - 20 cm) and (20 - 40 cm) were collected from waste dump sites, metal scrap dumps, fuel filling stations and auto-mechanic workshops and analyzed for physicochemical characteristics and heavy metal levels. Atomic absorption spectrophotometer was used for heavy metal determination while conventional analytical methods were employed for physicochemical parameters evaluation of the soil samples. At soil depths 0 - 20 cm and 20 - 40 cm the respective mean range of pH, electrical conductivity, organic matter and organic carbon contents in the soil samples were, 6.33 - 6.74, 101.46 - 123.21 <em>μ</em>S/cm, 6.41% - 8.35% and 13.73% - 16.14% for auto-mechanic workshops;6.92 - 7.43, 56.46 - 60.02 <em>μ</em>S/cm, 1.53% - 2.20% and 11.93% - 12.60% for fuel filling stations;7.14 - 7.84, 70.81 - 77.71 <em>μ</em>S/cm, 3.81% - 4.12% and 8.57% - 9.24% for metal scrap dumps;6.54 - 6.81, 94.40 - 100.71 <em>μ</em>S/cm, 8.83% - 10.75% and 18.26% - 20.81% for waste dump sites. The pH of the top soil samples from auto-mechanical workshop was below the WHO recommended limits for agricultural purposes. The physic-chemical characteristics of the soil samples decreased with soil depths indicating therefore that anthropogenic activities greatly influence the soil characteristics at the top soils than the sub-soils. The electrical conductivity values of top and sub-soil samples from the studied auto-mechanical workshops were above the recommended limits. At soil depths 0 - 20 cm and 20 - 40 cm, the respective mean range of Zn, Pb and Cd in the soil samples were 17.29 - 19.16 <em>μ</em>g/g, 0.704 - 0.96 <em>μ</em>g/g and 0.26 - 0.33 <em>μ</em>g/g for auto-mechanic workshops;4.13 - 4.88 <em>μ</em>g/g, 0.21 - 0.32 <em>μ</em>g/g and 0.03 - 0.11 <em>μ</em>g/g for fuel filling stations;30.02 - 36.11 <em>μ</em
文摘Studies were carried out to determine asbestos fiber levels in cosmetic (talc powder) and non-cosmetic (gauze pad, plastic filler and ceiling tiles) products sold in market outlets within Enugu, metropolis, Enugu State, Nigeria, using standard established procedures. The samples were pretreated based on its physical make-up and the asbestos fiber levels determined using scanning electron microscopy (SEM) with energy dispersing spectroscopy techniques. The mean range of asbestos fiber was, 0.02 - 0.06;0.01 - 0.05;0.01 - 0.04 and 0.03 - 0.06 f/cc for talc powder, gauze pads, plastic filler and ceiling tile samples respectively. The mean levels of asbestos fibers in the studied samples were within the recommended permissible limits. The samples contain asbestos fiber in the following decreasing order: ceiling tiles > talc powders > gauze pads > plastic fillers. Asbestos fiber was found present in the investigated local and foreign items sold in market outlets within the metropolis. This study shows that despite the ban on the use of asbestos in the industry in the manufacture of items meant for human use, its enforcement appears weak and lethargic and this could portend health danger especially in the use of produced items with high asbestos fiber friability such as talc powder.