Heavy metal pollution in and around Nairobi river, at Ngara and Gikomba, due to influx of metal wastes from cottage industries in the municipality
| dc.contributor.author | Raga, Odero Dishon | |
| dc.date.accessioned | 2026-04-29T08:51:55Z | |
| dc.date.available | 2026-04-29T08:51:55Z | |
| dc.date.issued | 1998 | |
| dc.description | Dissertation | |
| dc.description.abstract | Heavy metal pollution of a stretch of Nairobi river in the Ngara-Gikomba areas and their environs due to influx of wastes (0-15 cm) from cottage industries soil samples were industry locations between 0 and 1 was studied. Obtained Surface from cottage 000 m away from the centres of the installations. Plants were sampled at 5320 m away, whereas sediment and water samples were drawn from the Nairobi river between Chiromo and the downstream end of Gikomba. Chromium, determined by Atomic Pb, Cd, Absorption Cu and Zn were Spectrophotometry following aqua regia digestion of soils and sediments and HNO3-HCIO4 exchangeable EDTA. Digestion of plant heavy metals Linear were regression analyses extractable heavy metals percent OC or on soils and water samples. extracted using 0.05M of total and EDTA and sediments, pH, percent clay were performed. Heavy metal contents total of Amaranthus plants were regressed and EDTA-extractable metals to on soils' establish relationships. A remediation study was the undertaken using EDTA solutions. The results revealed that the cottage industries caused significantly (P = 0.05) higher levels of heavy metals in soils receiving wastes than in control soils. The heavy metal accumulations depended on the type, duration activity of activity centre. There of industry were and intensity and distance significant (P from 0.05) correlations between EDTA-extractable Pb, Cu and Zn and percent OC and percent Clay of the soils. Most metals in Amaranthus were significantly (P = 0.05) correlated with total soil metal levels, but very few with EDTA-extractable metals. There was increase in plant metal contents with increase of metal levels in soils. Significantly (P 0.05) higher metal levels of sediments and waters from Nairobi river were contributed by the wastes from cottage industries. The remediation study showed EDTA to extract substantial amounts of heavy metals from polluted soils, with maximum recovery of the metals accomplished using 0.1M or 0.25M EDTA. | |
| dc.description.sponsorship | NORAD | |
| dc.identifier.uri | https://www.suaire.sua.ac.tz/handle/20.500.14820/7513 | |
| dc.language.iso | en | |
| dc.publisher | Sokoine University of Agriculture | |
| dc.subject | Metal pollution | |
| dc.subject | Nairobi River | |
| dc.subject | Ngara | |
| dc.subject | Gikomba | |
| dc.subject | Metal wastes | |
| dc.title | Heavy metal pollution in and around Nairobi river, at Ngara and Gikomba, due to influx of metal wastes from cottage industries in the municipality | |
| dc.type | Thesis |