While I agree with all the points made in this opinion piece, I feel there is one more point obviously missing:
Lack of decisive government action
For over a decade every single government whether elected, appointed, military, civilian has failed to take on the "powerful agricultural businesses" who profit from this situation. Why is that? Cowardice, vested interest, laziness, ineptitude, or a combination thereof? Thailand, Tourism, Peoples' Health would all benefit from an independent, thorough and public investigation.