Relationship betw
Relationship
between nitrogenous pollution of borehole waters and distances separating them
from pit latrines and fertilized fields
Basie Vinger 1,
*Mbhuti Hlophe2 and Mailoo Selvaratnam2.
1Department of Chemistry, University of Limpopo
(Turfloop Campus), Sovenga 0711, Republic of South Africa.
2Department of Chemistry, North-West University
(Mafikeng Campus), Mmabatho, 2735, Republic of South Africa.[email protected],za
Abstract:The
occurrence of the following nitrogenous pollutants, namely ammonium, nitrite
and nitrate ions, was investigated in groundwater (borehole) sources of two
villages in North West Province of South Africa. The study was carried
out for two reasons. The Department of Water Affairs and Forestry (DWAF)
in Mmabatho had expressed anxiety over anomalous levels of nitrate ion (which
can be reduced to the toxic nitrite ion) in some groundwater sources in the
province (and this included some groundwater sources in the two villages). The
concentrations of the nitrogenous pollutants were monitored by differential pulse
polarography (DPP). This electrochemical method was selected because it is
fast, has low detection limits and is virtually free of interferences. The
study indicated that the main pollutant in the groundwater sources was nitrate
ions whose concentrations were higher than 25 ppm in some borehole
waters. This is more than two times higher than the 10 ppm N
specification recommended by the South African National Standard (SANS) for
drinking water. The study also indicated that the concentrations of
ammonium and nitrite ions in the borehole waters studied are not a health risk
to the communities. Important sources of groundwater pollution are pit latrines
and maize fields treated with nitrogen fertilizers. It was found that
groundwaters (borehole water) were polluted with nitrate ions when the
distances of the pit latrines and fertilized maize fields were respectively
less than 18 m and 13 m from the boreholes. The pollution was more
pronounced when the water table was shallow.
[Basie Vinger, Mbhuti Hlophe and Mailoo. Selvaratnam.
Relationship between nitrogenous pollution of borehole waters and distances
separating them from pit latrines and fertilized fields. Life Sci J
2012;9(1):402-407].(ISSN:1097-8135).http://www.lifesciencesite.com. 59
Keywords: Nitrogenous
pollution; methaemoglobinemia; and carcinogenesis; pit latrines; fertilized
maize fields; boreholes; differential pulse polarography. Full Text 59
