Corrective and preventive action should be taken at a higher level...not just by arresting the neighbour who probably was not much aware of the implications of pesticide fumes being inhaled.

First, there should be a state control on sale and use of specific types of pesticides. Mandatory procedures should be written and followed by personnel.

I can compare this to our radiographic testing crew who always have to work on written procedures...if there are rules for handling radioactive isotopes, then why not for poisonous chemicals? Why not barricade the whole area with sign boards and keep a vigil for some hours. Its neither expensive nor cumbersome.