The Environmental Protection Agency (EPA) is examining dust samples which landed on residents cars in the Mungret area of Limerick, which are believed to have originated from the Irish Cement Plant.
The dust was discovered on residents' cars in a number of housing estates in the vicinity of the plant over last weekend.
This latest incident has been criticised by the Limerick Against Pollution group, who are campaigning against controversial plans by Irish Cement to switch from using fossil fuels in its giant kiln to using alternative fuels like used tyres and other solid waste.
The EPA confirmed they are following up on the incident and have completed a site visit to Irish Cement and taken samples of the dust for examination.
A spokesperson said they are trying to establish the origin of the dust and if the EPA needs to take any other enforcement action.
In a statement this evening, Irish Cement said: "On Sunday morning a small spill of raw meal occurred at the cement factory in Mungret."
They said the kiln was stopped and the EPA were notified.
The company said there is "no risk to the public arising from the incident" and that they have been engaging with neighbours in the area following the event.
Local Fine Gael Cllr Daniel Butler said this latest incident further reinforces the fears people have about the ability of Irish Cement to operate safely and responsibly.
Emissions have now become all too frequent and they now expect the community to trust them to implement a far more volatile process of burning tyres and plastics, he said.
The EPA has already issued court proceedings against Irish Cement for alleged breaches of its operating licence at the plant in Limerick following a similar dust episode earlier this year.
The case is due to come before the District court in Limerick next March.