Abstract:
Antibiotics that are added to the drinking water of poultry and the feed of fattening
livestock to promote growth and reduce illness. When manure containing antibiotic
residues are used as plant fertilizer they may erode or leach and contaminate soil and water
resources. This research was conducted to evaluate the accumulation of gentamicin and
oxytetracycline in lettuce leaves, radish bulbs and cucumber fruits in a field experiment and
in a pot experiment, where crops are grown in two soils mixed with 0 or 5 % manure and
irrigated with water containing 20 mg/L of each of the tested antibiotics. After harvest,
plant tissues were analyzed by ELISA in both experiments. Regarding field experiment,
concentrations of oxytetracycline and gentamicin used in the field were 30 mg/Kg of dried
manure. The antibiotics were mixed in manure and amended in the soil. The results of field
experiment showed that oxytetracycline wasn’t detected in plant tissue. However,
gentamicin accumulated in radish bulb in soil treated with manure and gentamicin. For the
pot experiment, the results of analysis indicated that oxytetracycline and gentamicin can be
accumulated in radish, lettuce and cucumber and the addition of manure to the potted soil
increased the uptake of gentamicin significantly in radish, lettuce and cucumber. The three
crops can accumulate oxytetracycline applied in irrigation water in the pot experiment but
not in field experiment when oxytetracycline was applied inside manure in the soil. It is
recommended that the haphazard use of antibiotics be controlled, and antibiotics be used
for the treatment of sick animals only.
