The five victims aged between five and 14 years, some of whom were related, fell sick after eating the doughnuts cooked by a teenage girl on Tuesday evening in Kimoukro village around 35 km from the political capital Yamoussoukro.
''The young girl of 13 or 14 was at home while her mother was working in the fields, and she confused the powder with baking powder,'' Dr Augustin Dougrou told Reuters yesterday, adding that the girl was among the five dead.
''It was a product used to treat insect infestations on crops.
The eight of them ate the doughnuts,'' he said, adding the girl's mother and other family members were being questioned at a military police station near Kimoukro.
A local newspaper said the girl's mother sold the farm chemicals, but she had denied storing them inside the house.
Some Ivorians have become increasingly wary about what they eat after an outbreak of birdflu last year, and after tonnes of toxic waste were dumped in the economic capital Abidjan last August, killing 15 people and making thousands ill.
Fishing was banned in the city's lagoon which had been polluted by waste offloaded from a tanker chartered by Dutch-based oil trader, and vegetable plots near the 17 sites where the waste was dumped were also destroyed.
REUTERS TB BST0422