the story is that the oil used to prepare the food was stored in used containers that once stored the pesticide; this pesticide is banned in most places, but cheap to make and now generic, so the cheap locally manufactured version (made in India or China) is used by many poor farmers who can't afford the better safer pesticides.
Then we run into this:
WHO also believes that monocrotophos routinely kills people as well as insects. In a 2009 report, the agency points out that organophosphate exposure is linked to depression and increased suicide risk. It notes that the suicide rate among the poor farmers of India has been steadily rising – at the time of the report it was officially more than 17,000 people a year (largely considered an underestimate). Many of those farmers killed themselves by drinking monocrotophos. Between 1997 and 2005, pesticide suicides in India overall topped 190,000 people, enough to clear out a small city.