Determination of Spatial Chromium Contamination of the Environment around Industrial Zones

Abstract

This study was conducted to determine the spatial levels of chromium contamination of water, agricultural soil, and vegetables in the leather tanning industrial areas using spectrophotometric methods. The results showed elevated accumulation of total Cr ranging from 10.85 ± 0.885 mg/L to 39.696 ± 0.326 mg/L, 16.225 ± 0.12 mg/Kg to 1581.667 ± 0.122 mg/Kg, and 1.0758 ± 0.05348 mg/Kg to 11.75 ± 0.206 mg/Kg in water, agricultural soil, and vegetable samples, respectively. The highest levels of chromium (VI) found from the speciation study were 2.23 ± 0.032 mg/Kg and 0.322 ± 0.07 mg/L in soil and water samples, respectively, which decreased with distance from the tannery. Among the vegetables, the highest load of Cr(VI) was detected in onion root (0.048 ± 0.065 mg/Kg) and the lowest (0.004 ± 0.007 mg/Kg) in fruit of green pepper. The detected levels of Cr in all of the suggested samples were above the WHO permissible limits. The variations of the levels Cr(III) and Cr(VI) contamination of the environment with distance from the tannery were statistically significant (p = 0.05). Similarly, significant difference in the levels of Cr among the tested vegetables was recorded. The levels increased with decreasing distance from the effluent channel.

Determination of Total Chromium and Chromium Species in Kombolcha Tannery Wastewater, Surrounding Soil, and Lettuce Plant Samples, South Wollo, Ethiopia

“…The value of total Cr (22.6 mg/kg) in the soil sample of this study was much lower than the values reported in Homa et al (254.25-1581.66 mg/kg) [15] as well as the permissible limit (100 mg/kg) by WHO and FAO. The total Cr, Cr(III), and Cr(VI) which were obtained in the lettuce plant samples were also lower than those reported by Homa et al (7.4163-10.473, 7.3913-10.36, and 0.025-0.113 mg/kg, resp.)…”

“…The concentration of Cr(III) is also extremely higher than the reported value by Homa et al (19.126-39.374 mg/L) [15]. Moreover, the amount of Cr(VI) obtained in this study at the discharging point was higher than that of Homa et al (0-0.322 mg/L) [15]. In the downstream case, all chromium species were lower than other reported values.…”

“…The amounts of total Cr at the discharging point of Kombolcha tannery wastewater were higher than the values described by Homa et al (19.126-39.696 mg/L) [15]. The concentration of Cr(III) is also extremely higher than the reported value by Homa et al (19.126-39.374 mg/L) [15]. Moreover, the amount of Cr(VI) obtained in this study at the discharging point was higher than that of Homa et al (0-0.322 mg/L) [15].…”

“…The amounts of total Cr at the discharging point of Kombolcha tannery wastewater were higher than the values described by Homa et al (19.126-39.696 mg/L) [15]. The concentration of Cr(III) is also extremely higher than the reported value by Homa et al (19.126-39.374 mg/L) [15].…”

“…The digested samples were kept in a refrigerator for 12 hr. Then, the amount of total Cr in the sample solutions was determined [15].…”