HERBICIDES in Asian rice - IRRI books - International Rice ...

Given the current state of knowledge about rice, relatively little additional research
may be needed to substantially reduce the toxic risk of herbicide use. In the
past, herbicide research often concentrated on efficacy trials under local conditions.
While this applied work needs to continue, additional attention should be given to
safety and environmental protection. Although local persistence of each formulation
should be assessed, a simple immunoassay or similar test should suffice.
Increased effort is needed to more effectively deliver existing information to potential
users, through local education and agricultural extension programs that provide
demonstrations, recommendations, and advice to growers (B. L. Brennan, University
of Hawaii, Honolulu, HI, USA, pers. commun., 1994). Unsafe storage, mixing,
and container disposal may be the most difficult area, and corporate efforts are
needed to address these problems.
Use of defoliants during the war in Southeast Asia and several spectacular accidental
spills have fostered a negative public image of herbicide use in the industrialized
nations. However, in any part of the world, the toxic risk from insecticide application,
from sewage and industrial waste, and from urbanization is much greater than
the risk from herbicide use. Government policy in regard to rice herbicides can legitimately
be based on land use, water, health, social, demographic, and cultural issues.
The environmental impact of herbicides on nontarget organisms is negligible.
CITED REFERENCES
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Impact of herbicide use on the environment 105