ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA
Thirty percent of residents in Nairobi practise urban agriculture (UA) with a majority of the farmers using untreated sewage to irrigate crop and fodder. Due to the environmental and health risks associated with wastewater irrigation, a study was carried out in partnership with farmers in Kibera and...
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| Format: | Article |
| Language: | English |
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Universidad Autónoma de Yucatán
2009-08-01
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| Series: | Tropical and Subtropical Agroecosystems |
| Subjects: | |
| Online Access: | http://www.revista.ccba.uady.mx/ojs/index.php/TSA/article/view/367 |
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| author | Nancy Njarua Karanja M. Njenga G. Prain E. Kang’ethe G. Kironchi C. Githuku P. Kinyari G.K. Mutua |
| author_facet | Nancy Njarua Karanja M. Njenga G. Prain E. Kang’ethe G. Kironchi C. Githuku P. Kinyari G.K. Mutua |
| author_sort | Nancy Njarua Karanja |
| collection | DOAJ |
| description | Thirty percent of residents in Nairobi practise urban agriculture (UA) with a majority of the farmers using untreated sewage to irrigate crop and fodder. Due to the environmental and health risks associated with wastewater irrigation, a study was carried out in partnership with farmers in Kibera and Maili Saba which are informal settlements along the Ngong River, a tributary of the Nairobi River Basin. Soil, water, crops and human faecal samples from the farming and non-farming households were analysed to elucidate sources, types and level of heavy metal pollutants in the wastewater and the pathogen loads in humans and vegetable crops.  Heavy metal accumulation in soils collected from Kibera and Maili Saba were Cd (14.3 mg kg-1), Cr (9.7 mg kg-1) and Pb (1.7 mg kg-1) and Cd (98.7 mg kg-1),  Cr (4.0 mg kg-1) and Pb (74.3 mg kg-1), respectively. This led to high phytoaccumulation of Cd, Cr and Pb in the crops that exceeded the maximum permissible limits. No parasitic eggs were detected in the vegetables but coliform count in the wastewater was 4.8 x108±2.2 x1011/100ml. Soils irrigated with this water had parasitic eggs and non-parasitic larvae counts of 54.62 and 27.5/kg respectively. Faecal coliform and parasitic eggs of common intestinal parasites increased in leafy vegetable sampled from the informal markets along the value chain. |
| first_indexed | 2024-04-13T00:40:23Z |
| format | Article |
| id | doaj.art-e5a0f8f2ac0a4243b476f91c43e58553 |
| institution | Directory Open Access Journal |
| issn | 1870-0462 |
| language | English |
| last_indexed | 2024-04-13T00:40:23Z |
| publishDate | 2009-08-01 |
| publisher | Universidad Autónoma de Yucatán |
| record_format | Article |
| series | Tropical and Subtropical Agroecosystems |
| spelling | doaj.art-e5a0f8f2ac0a4243b476f91c43e585532022-12-22T03:10:12ZengUniversidad Autónoma de YucatánTropical and Subtropical Agroecosystems1870-04622009-08-011218597126ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYANancy Njarua Karanja0M. NjengaG. PrainE. Kang’etheG. KironchiC. GithukuP. KinyariG.K. MutuaINTERNATIONAL POTATO CENTRE(CIP)Thirty percent of residents in Nairobi practise urban agriculture (UA) with a majority of the farmers using untreated sewage to irrigate crop and fodder. Due to the environmental and health risks associated with wastewater irrigation, a study was carried out in partnership with farmers in Kibera and Maili Saba which are informal settlements along the Ngong River, a tributary of the Nairobi River Basin. Soil, water, crops and human faecal samples from the farming and non-farming households were analysed to elucidate sources, types and level of heavy metal pollutants in the wastewater and the pathogen loads in humans and vegetable crops.  Heavy metal accumulation in soils collected from Kibera and Maili Saba were Cd (14.3 mg kg-1), Cr (9.7 mg kg-1) and Pb (1.7 mg kg-1) and Cd (98.7 mg kg-1),  Cr (4.0 mg kg-1) and Pb (74.3 mg kg-1), respectively. This led to high phytoaccumulation of Cd, Cr and Pb in the crops that exceeded the maximum permissible limits. No parasitic eggs were detected in the vegetables but coliform count in the wastewater was 4.8 x108±2.2 x1011/100ml. Soils irrigated with this water had parasitic eggs and non-parasitic larvae counts of 54.62 and 27.5/kg respectively. Faecal coliform and parasitic eggs of common intestinal parasites increased in leafy vegetable sampled from the informal markets along the value chain.http://www.revista.ccba.uady.mx/ojs/index.php/TSA/article/view/367Urban agricultureslumsheavy metal pollutionbiological contaminantsurbanization. |
| spellingShingle | Nancy Njarua Karanja M. Njenga G. Prain E. Kang’ethe G. Kironchi C. Githuku P. Kinyari G.K. Mutua ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA Tropical and Subtropical Agroecosystems Urban agriculture slums heavy metal pollution biological contaminants urbanization. |
| title | ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA |
| title_full | ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA |
| title_fullStr | ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA |
| title_full_unstemmed | ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA |
| title_short | ASSESSMENT OF ENVIRONMENTAL AND PUBLIC HEALTH HAZARDS IN WASTEWATER USED FOR URBAN AGRICULTURE IN NAIROBI, KENYA |
| title_sort | assessment of environmental and public health hazards in wastewater used for urban agriculture in nairobi kenya |
| topic | Urban agriculture slums heavy metal pollution biological contaminants urbanization. |
| url | http://www.revista.ccba.uady.mx/ojs/index.php/TSA/article/view/367 |
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