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Preventive measures
Substitution with less toxic pesticides
Substituting less toxic pesticides for highly toxic ones is an effective and simple
preventive measure. Certain highly toxic pesticides, such as parathion, are
responsible for most poisonings (Table 1). Their replacement with less dangerous
pesticides has been successful in many respects. However, the hazards of
the replacement pesticide should not be underestimated; low toxicity pyrethroids
have caused poisonings as well. Changing to a less hazardous formulation
can also be an effective safety measure. For example, although
carbofuran ranks high in toxicity, a 3-5% granular preparation can be used
safely.
Selection of the appropriate devices for application
To minimize, as much as possible, dermal contamination and uptake of the
toxicant, careful attention must be paid to the selection of appropriate and safe
devices for the application of pesticides (Table 2).
Year
Table 1. Proportion of acute poisonings involving parathion.
% parathion among % of poisonings
pesticides used caused by parathion
1981 4.73 85.5
1982 3.78 81.5
1983 5.01 87.7
1984
Source: Huang 1985.
4.02 89.8
Table 2. Degree of dermal contamination after spraying parathion
using various devices in a rice field.
Dermal contamination after
2
20 mm (g/cm) Concentration in
Device and method of
application
Fine mist spraying
Longdistanceprojection
High-volume spraying
Tractor driven equipment
Hand pressure
Source: Chen 1985.
Front of
Hand leg Foot
15.40 10.40 7.55
20.85 0.05 1.46
1.27 - 0.94
0.08 -
12.55 6.28 6.45
Trunk
2.44
-
0.43
0.47
-
air at breathing
zone (mg/rn3)
0.25
0.01
-
0.01
0.04
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