The official at Nafdac told the BBC's Stephanie Hegarty that the tests were still ongoing:
"We are not done with comprehensive tests. We are still in the laboratory. We haven't concluded analysis and it is not something we can conclude in two days."
"We are yet to conclude the chemical and biological analysis," he added.
Mr Adewole had said the agency would "release detailed findings to public as soon as it concludes investigations", adding that Nigerians should remain calm.
It is not clear where the 102 seized sacks of rice came from but rice made from plastic pellets was found in China last year
Mr Mamudu had said the rice was very sticky after it was boiled and "only God knows what would have happened" if people ate it.
The BBC's Martin Patience in Lagos, who felt the rice, said it looked real but had a faint chemical odour.
The Lagos customs chief had called on "economic saboteurs who see yuletide season as a peak period for their nefarious acts to desist from such illegal" business activity.
Is the rice still on sale in the markets?
We haven't heard any reports that the rice is still on sale in markets. Customs officials were investigating but as of now have found nothing.
Nigeria's custom officials say they seized a total of 102 sacks, each containing 25kg (55lb), branded "Best Tomato Rice".
It is, however, unclear how many bags had been sold, if any, and if there are other forms of contraband in the market.
Has anyone eaten it?
We haven't heard of any members of the public eating it.
Customs officials cooked the rice and said that the texture was very gummy and it smelled odd, they refused to eat it.
When asked the same question on Twitter, Health Minister Isaac Adewole joked that no, he wouldn't eat it without salt.
