They were admitted to the government hospital here after they drank the water being supplied from Melakottai village and started vomitting and complained of giddiness, they said.
Their condition is stable, doctors at the hospital said.
Police said water from the 30,000 litre overhead tank at Melakottai village was also being supplied to Kizhaku Kudiyiruppu and Samba hamlets.
The water was tested and found to have been mixed with pesticide granules, they said.