Heavy metal levels in drinking water sources and their potential human health risks in Chingola district of Zambia
Date
2017
Authors
Hamwiinga, Francis
Journal Title
Journal ISSN
Volume Title
Publisher
The University of Zambia
Abstract
One of the factors impeding access to safe water is water pollution. Of particular concern is
heavy metal contamination of water bodies. This study was aimed at determining the levels of
heavy metals in drinking water sources of Chingola District of Zambia and their potential human
health risks in Chingola District of Zambia. A cross sectional study design was used. A total of
60 water samples were collected. 30 water samples were collected in the dry season in the month
of October, 2016 and another 30 were collected in the wet season in the months of February and
March, 2017. For each season 10 water samples were collected from each of the three water
sources. i.e. Tap water, Urban ground water sources and Rural ground water sources. Heavy
metal analysis was done using Atomic Absorption Spectrophotometer (AAS). This study
revealed that concentrations of Iron, Manganese, Lead, Nickel and Arsenic were beyond
maximum permissible levels in various water sources. Chromium and Cadmium was below
detection limit in all water samples. The median concentrations of iron, arsenic, copper and
manganese in drinking water from the Tap, rural and urban ground water sources were different,
and this difference was statistically significant (p<0.05). The median concentrations of arsenic,
nickel, manganese and cobalt were different between dry and wet season, and this difference was
statistically significant (p<0.05). Non- carcinogenic risk assessment revealed that arsenic, iron,
lead and copper are heavy metals which are likely to produce non carcinogenic adverse health
effects. Carcinogenic risk assessment showed that the levels of arsenic and lead have a high
likelihood of producing carcinogenic adverse health effects. Sources of heavy metals in water
seems to be both natural and from human activities. The water utility company should improve
its water treatment processes and rural communities should be provided with household water
filters.
Description
Thesis
Keywords
Water--Pollution--Heavy metal--Zambia