Agriculture Reference
In-Depth Information
Figure 6.2 Fecal coliform contamination levels of irrigation water used during
the study period (piped water was excluded because no fecal coliforms were
detected during the study period)
chlorpyrifos kg
1
lettuce, the child would have to eat close to 200 g lettuce per
day. The amount of lettuce (usually served with other staples, e.g. rice) is
usually less than 30 g daily. However, if a child was malnourished they might
be more susceptible; moreover, fetal (via maternal) or chronic
neurodevelopmental effects might occur, since they are not always included in
MRL analysis.
Contamination pathway study
FC levels of irrigation water used
With the exception of piped water, FC contamination levels of irrigation
water from different sources used in the study significantly exceeded a
geometric mean of 1
10
3
100ml
1
(WHO recommended level for
unrestricted irrigation
4
). For details, see Figure 6.2. Significantly higher FC
counts were recorded in water samples from streams than from shallow wells
in Kumasi.
The maximum FC contamination densities for shallow well and stream
samples in Kumasi were 4
10
6
100ml
1
and 4
10
8
100ml
1
, respectively,
while drain and stream samples in Accra showed densities of 9
10
6
100ml
1
and 2
10
7
100ml
1
, respectively. This corresponds well with data reported
by several researchers (Cornish et al, 1999; Mensah et al, 2001; Keraita et al,
2002) in the same study area.
Helminth egg contamination levels of irrigation water used
No eggs were recorded in piped water during the study period. Arithmetic
mean
5
helminth egg contamination levels in irrigation water from drains,
