Sewage re-use for irrigation in Athi River town Kenya: its implications on public health

Occupational environmental health associated with both industrial and domestic sewage reuse for food production in Athi River town Kenya has been studied. The levels of toxic heavy metals such as lead, cadmium, selenium and arsenic in the soil, roof crops, leaf crops and fruits (or seed) were determined using atomic absorption spectoscophy (AAS). In soils the average levels of lead and cadmium were 0.44mg/g and 0.13mg/g respectively. The crops analysed were selected as root crops, leaf crops and fruits (or seed) crops. The levels of lead found in these crops were 0.06 μg/g, 0.01 μg/g and fruit 0.05 μg/g for root, leaf and fruit crops respectively. Similarly, the cadmium in root, leaf and fruit crops was 0.016 μg/g, 0.03 μg/g and 0.02 μg/g respectively. Coliform counts were greater than 300 counts per 100ml in all samples, which gave a positive indication of the presence of Escherichia coli.