Question

farmer spray pesticide to field and in next day he felt ill. why?

Answer 1

the probable reason might be when he was spraying pesticides(chemical given to plants to avoid pest growth) he might have either inhaled it or got in contact with it. there are several diseases which occur when you come in contact with. contact with chemicals arouses chemical related issues and this might have caused him to be ill.

Answer 2

The pesticides which farmers generally use are toxic they may be organo -phosphates and other inorganic synthetic residues .
These are very harmful to health thats why while spraying the pesticides in the fields farmers take proper care ,they have all the equipments needed to spray and finely covered with cloth all over the body to avoid spills and splashs on the person.
If sufficient and proper care is not taken the farmer may get exposed to the spray of pesticide and may certainly fall ill 
There may be high risks to the person who has been exposed to the pesticide 
In the above case the person might not have implemented proper care while doing the job so he might have exposed to the pesticide and now might have fallen ill...may be suffering from nausea ,headache,dizziness,not seeing properly and may also undergone many more diseases 
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