Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya

Julius Kioko Nzeve; Sydney Likhumba Ikubano

doi:doi:10.11648/j.jher.20210702.13

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Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya

Julius Kioko Nzeve, Sydney Likhumba Ikubano

Published in Journal of Health and Environmental Research (Volume 7, Issue 2)

Received: 6 April 2021 Accepted: 19 April 2021 Published: 26 April 2021

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Abstract

With the increase of global population, wastewater treatment facilities face a major challenge of managing the large quantities of sewage sludge produced in urban areas. Due to this challenge many wastewater treatment plants have opted for use of sewage sludge as organic fertilizer to boost agricultural production. In Machakos Decentralized Treatment Facility (DFT), sewage sludge is usually sold to locals as fertilizer to boost crop production within the municipality. However, sewage sludge produced in municipal wastewater treatment plants is known to contain various heavy metals that may limit its usage as agricultural fertilizer. Studies have shown that sewage sludge has been associated with heavy metals which are linked to harmful effects on humans and environmental health. This study investigated the levels of various heavy metals and macronutrients from sewage sludge obtained from Machakos town wastewater treatment plant to test its suitability for use as fertilizer. Sewage sludge samples were obtained from the treatment plant at Mitheu and transported to Nairobi Agricultural Research Laboratory (NARL) for analysis of heavy metals (Cu, Zn, Mn, and Fe) and macronutrients (N, P, Ca, Mg and K). The results for the heavy metals were Zn=171.13±237mg/kg; Fe=17,877±15,700mg/kg; Mn=445.67±213mg/kg and Cu=41.1±16.71mg/kg) while the macronutrients were K=0.17±0.09%, P=1.26±1.75%, N=0.74±0.47%, Ca=0.48±0.72% and Mg=0.10±0.06%. The heavy metal concentrations were below Kenya Bureau of Standards (KEBS) and international permissible limits for sewage sludge application in agriculture and therefore deemed safe. The study concluded that the sewage sludge from Machakos Decentralized Treatment Facility is rich in nutrients and thus a potential fertilizing agent that can be used to boost plant growth in agricultural farms. However, it was noted that not all the wastewater produced in Machakos town gets into the DFT for treatment. Therefore, the study recommended that the county government of Machakos should endeavor to enlarge the small DFT treatment plant to accommodate the large quantities of wastewater generated within the town.

Published in	Journal of Health and Environmental Research (Volume 7, Issue 2)
DOI	10.11648/j.jher.20210702.13
Page(s)	99-104
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Heavy Metals, Macronutrients, Sewage Sludge, Organic Fertilizer, Machakos Town

References

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APA Style

Julius Kioko Nzeve, Sydney Likhumba Ikubano. (2021). Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. Journal of Health and Environmental Research, 7(2), 99-104. https://doi.org/10.11648/j.jher.20210702.13

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ACS Style

Julius Kioko Nzeve; Sydney Likhumba Ikubano. Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. J. Health Environ. Res. 2021, 7(2), 99-104. doi: 10.11648/j.jher.20210702.13

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AMA Style

Julius Kioko Nzeve, Sydney Likhumba Ikubano. Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. J Health Environ Res. 2021;7(2):99-104. doi: 10.11648/j.jher.20210702.13

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@article{10.11648/j.jher.20210702.13,
  author = {Julius Kioko Nzeve and Sydney Likhumba Ikubano},
  title = {Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya},
  journal = {Journal of Health and Environmental Research},
  volume = {7},
  number = {2},
  pages = {99-104},
  doi = {10.11648/j.jher.20210702.13},
  url = {https://doi.org/10.11648/j.jher.20210702.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jher.20210702.13},
  abstract = {With the increase of global population, wastewater treatment facilities face a major challenge of managing the large quantities of sewage sludge produced in urban areas. Due to this challenge many wastewater treatment plants have opted for use of sewage sludge as organic fertilizer to boost agricultural production. In Machakos Decentralized Treatment Facility (DFT), sewage sludge is usually sold to locals as fertilizer to boost crop production within the municipality. However, sewage sludge produced in municipal wastewater treatment plants is known to contain various heavy metals that may limit its usage as agricultural fertilizer. Studies have shown that sewage sludge has been associated with heavy metals which are linked to harmful effects on humans and environmental health. This study investigated the levels of various heavy metals and macronutrients from sewage sludge obtained from Machakos town wastewater treatment plant to test its suitability for use as fertilizer. Sewage sludge samples were obtained from the treatment plant at Mitheu and transported to Nairobi Agricultural Research Laboratory (NARL) for analysis of heavy metals (Cu, Zn, Mn, and Fe) and macronutrients (N, P, Ca, Mg and K). The results for the heavy metals were Zn=171.13±237mg/kg; Fe=17,877±15,700mg/kg; Mn=445.67±213mg/kg and Cu=41.1±16.71mg/kg) while the macronutrients were K=0.17±0.09%, P=1.26±1.75%, N=0.74±0.47%, Ca=0.48±0.72% and Mg=0.10±0.06%. The heavy metal concentrations were below Kenya Bureau of Standards (KEBS) and international permissible limits for sewage sludge application in agriculture and therefore deemed safe. The study concluded that the sewage sludge from Machakos Decentralized Treatment Facility is rich in nutrients and thus a potential fertilizing agent that can be used to boost plant growth in agricultural farms. However, it was noted that not all the wastewater produced in Machakos town gets into the DFT for treatment. Therefore, the study recommended that the county government of Machakos should endeavor to enlarge the small DFT treatment plant to accommodate the large quantities of wastewater generated within the town.},
 year = {2021}
}

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TY  - JOUR
T1  - Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya
AU  - Julius Kioko Nzeve
AU  - Sydney Likhumba Ikubano
Y1  - 2021/04/26
PY  - 2021
N1  - https://doi.org/10.11648/j.jher.20210702.13
DO  - 10.11648/j.jher.20210702.13
T2  - Journal of Health and Environmental Research
JF  - Journal of Health and Environmental Research
JO  - Journal of Health and Environmental Research
SP  - 99
EP  - 104
PB  - Science Publishing Group
SN  - 2472-3592
UR  - https://doi.org/10.11648/j.jher.20210702.13
AB  - With the increase of global population, wastewater treatment facilities face a major challenge of managing the large quantities of sewage sludge produced in urban areas. Due to this challenge many wastewater treatment plants have opted for use of sewage sludge as organic fertilizer to boost agricultural production. In Machakos Decentralized Treatment Facility (DFT), sewage sludge is usually sold to locals as fertilizer to boost crop production within the municipality. However, sewage sludge produced in municipal wastewater treatment plants is known to contain various heavy metals that may limit its usage as agricultural fertilizer. Studies have shown that sewage sludge has been associated with heavy metals which are linked to harmful effects on humans and environmental health. This study investigated the levels of various heavy metals and macronutrients from sewage sludge obtained from Machakos town wastewater treatment plant to test its suitability for use as fertilizer. Sewage sludge samples were obtained from the treatment plant at Mitheu and transported to Nairobi Agricultural Research Laboratory (NARL) for analysis of heavy metals (Cu, Zn, Mn, and Fe) and macronutrients (N, P, Ca, Mg and K). The results for the heavy metals were Zn=171.13±237mg/kg; Fe=17,877±15,700mg/kg; Mn=445.67±213mg/kg and Cu=41.1±16.71mg/kg) while the macronutrients were K=0.17±0.09%, P=1.26±1.75%, N=0.74±0.47%, Ca=0.48±0.72% and Mg=0.10±0.06%. The heavy metal concentrations were below Kenya Bureau of Standards (KEBS) and international permissible limits for sewage sludge application in agriculture and therefore deemed safe. The study concluded that the sewage sludge from Machakos Decentralized Treatment Facility is rich in nutrients and thus a potential fertilizing agent that can be used to boost plant growth in agricultural farms. However, it was noted that not all the wastewater produced in Machakos town gets into the DFT for treatment. Therefore, the study recommended that the county government of Machakos should endeavor to enlarge the small DFT treatment plant to accommodate the large quantities of wastewater generated within the town.
VL  - 7
IS  - 2
ER  -

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Author Information

Julius Kioko Nzeve

Department of Environmental Sciences, Machakos University, Machakos, Kenya
Sydney Likhumba Ikubano

Department of Environmental Sciences, Machakos University, Machakos, Kenya

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Julius Kioko Nzeve, Sydney Likhumba Ikubano. (2021). Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. Journal of Health and Environmental Research, 7(2), 99-104. https://doi.org/10.11648/j.jher.20210702.13

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ACS Style

Julius Kioko Nzeve; Sydney Likhumba Ikubano. Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. J. Health Environ. Res. 2021, 7(2), 99-104. doi: 10.11648/j.jher.20210702.13

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AMA Style

Julius Kioko Nzeve, Sydney Likhumba Ikubano. Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya. J Health Environ Res. 2021;7(2):99-104. doi: 10.11648/j.jher.20210702.13

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@article{10.11648/j.jher.20210702.13,
  author = {Julius Kioko Nzeve and Sydney Likhumba Ikubano},
  title = {Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya},
  journal = {Journal of Health and Environmental Research},
  volume = {7},
  number = {2},
  pages = {99-104},
  doi = {10.11648/j.jher.20210702.13},
  url = {https://doi.org/10.11648/j.jher.20210702.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jher.20210702.13},
  abstract = {With the increase of global population, wastewater treatment facilities face a major challenge of managing the large quantities of sewage sludge produced in urban areas. Due to this challenge many wastewater treatment plants have opted for use of sewage sludge as organic fertilizer to boost agricultural production. In Machakos Decentralized Treatment Facility (DFT), sewage sludge is usually sold to locals as fertilizer to boost crop production within the municipality. However, sewage sludge produced in municipal wastewater treatment plants is known to contain various heavy metals that may limit its usage as agricultural fertilizer. Studies have shown that sewage sludge has been associated with heavy metals which are linked to harmful effects on humans and environmental health. This study investigated the levels of various heavy metals and macronutrients from sewage sludge obtained from Machakos town wastewater treatment plant to test its suitability for use as fertilizer. Sewage sludge samples were obtained from the treatment plant at Mitheu and transported to Nairobi Agricultural Research Laboratory (NARL) for analysis of heavy metals (Cu, Zn, Mn, and Fe) and macronutrients (N, P, Ca, Mg and K). The results for the heavy metals were Zn=171.13±237mg/kg; Fe=17,877±15,700mg/kg; Mn=445.67±213mg/kg and Cu=41.1±16.71mg/kg) while the macronutrients were K=0.17±0.09%, P=1.26±1.75%, N=0.74±0.47%, Ca=0.48±0.72% and Mg=0.10±0.06%. The heavy metal concentrations were below Kenya Bureau of Standards (KEBS) and international permissible limits for sewage sludge application in agriculture and therefore deemed safe. The study concluded that the sewage sludge from Machakos Decentralized Treatment Facility is rich in nutrients and thus a potential fertilizing agent that can be used to boost plant growth in agricultural farms. However, it was noted that not all the wastewater produced in Machakos town gets into the DFT for treatment. Therefore, the study recommended that the county government of Machakos should endeavor to enlarge the small DFT treatment plant to accommodate the large quantities of wastewater generated within the town.},
 year = {2021}
}

Copy | Download

TY  - JOUR
T1  - Heavy Metals and Macronutrients Concentrations in Sewage Sludge Obtained from Decentralized Treatment Facility, Machakos Town, Kenya
AU  - Julius Kioko Nzeve
AU  - Sydney Likhumba Ikubano
Y1  - 2021/04/26
PY  - 2021
N1  - https://doi.org/10.11648/j.jher.20210702.13
DO  - 10.11648/j.jher.20210702.13
T2  - Journal of Health and Environmental Research
JF  - Journal of Health and Environmental Research
JO  - Journal of Health and Environmental Research
SP  - 99
EP  - 104
PB  - Science Publishing Group
SN  - 2472-3592
UR  - https://doi.org/10.11648/j.jher.20210702.13
AB  - With the increase of global population, wastewater treatment facilities face a major challenge of managing the large quantities of sewage sludge produced in urban areas. Due to this challenge many wastewater treatment plants have opted for use of sewage sludge as organic fertilizer to boost agricultural production. In Machakos Decentralized Treatment Facility (DFT), sewage sludge is usually sold to locals as fertilizer to boost crop production within the municipality. However, sewage sludge produced in municipal wastewater treatment plants is known to contain various heavy metals that may limit its usage as agricultural fertilizer. Studies have shown that sewage sludge has been associated with heavy metals which are linked to harmful effects on humans and environmental health. This study investigated the levels of various heavy metals and macronutrients from sewage sludge obtained from Machakos town wastewater treatment plant to test its suitability for use as fertilizer. Sewage sludge samples were obtained from the treatment plant at Mitheu and transported to Nairobi Agricultural Research Laboratory (NARL) for analysis of heavy metals (Cu, Zn, Mn, and Fe) and macronutrients (N, P, Ca, Mg and K). The results for the heavy metals were Zn=171.13±237mg/kg; Fe=17,877±15,700mg/kg; Mn=445.67±213mg/kg and Cu=41.1±16.71mg/kg) while the macronutrients were K=0.17±0.09%, P=1.26±1.75%, N=0.74±0.47%, Ca=0.48±0.72% and Mg=0.10±0.06%. The heavy metal concentrations were below Kenya Bureau of Standards (KEBS) and international permissible limits for sewage sludge application in agriculture and therefore deemed safe. The study concluded that the sewage sludge from Machakos Decentralized Treatment Facility is rich in nutrients and thus a potential fertilizing agent that can be used to boost plant growth in agricultural farms. However, it was noted that not all the wastewater produced in Machakos town gets into the DFT for treatment. Therefore, the study recommended that the county government of Machakos should endeavor to enlarge the small DFT treatment plant to accommodate the large quantities of wastewater generated within the town.
VL  - 7
IS  - 2
ER  -

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