The Stanlow refinery released 50 tonnes of dust in two fallout incidents, it has been revealed.

Much of the dust released into the atmosphere then fell in the Ellesmere Port area, leaving cars and homes coated in a layer of what EET Fuels has said was "non-toxic and non-hazardous" on Tuesday, September 17.

Having been alerted about the incident, the UK Health Security Agency subsequently said: "We have been made aware of the incident and understand that members of the public may be concerned, however we would like to reassure people that the risk to health is low.

"However, any exposure to dust for however short a period may cause temporary eye and respiratory irritation. Anyone who has touched the dust and is experiencing skin irritation should wash the area with soap and water. We would also advise that any individuals who are experiencing respiratory irritation should contact their GP or NHS 111."

Initially EET Fuels put out a 'community statement' on the company's website, referring to one incident at about 1.30pm on that day, "which resulted from the unplanned shutdown of a process unit."

But following queries raised by Runcorn and Helsby MP Mike Amesbury, the company has since provided further details in an email to the Labour politician, the contents of which have been posted on his Facebook page.

In it, EET Fuels acknowledged there was a second fallout incident the day before, on Monday, September 16. Between the two incidents, an estimated total of 50 tonnes of dust was released.

EET Fuels said: "There were two releases of dust, one on Monday evening and one on Tuesday early afternoon.

"Both were linked to the same event – an unplanned shutdown of one of our units due to an electrical fault. We are investigating this fully and will share this investigation with the regulator once complete.

"We understand that there was some localised fallout associated with the dust release on Monday and more widespread fallout associated with the release on Tuesday (this is based on both weather conditions at the time and the number of complaints we have received for both instances.)

"We have formally reported both releases to the Environment Agency, in line with the requirements within our permit, with a total estimated volume of release of 50 tonnes.

"As previously communicated, the dust is non-toxic and non-hazardous and does not pose any health or safety risks to people or the environment. The dust formed from the catalyst material used in one of the process units on site.

"The dust primarily consists of non-crystalline silica, aluminium oxide, and zeolites.

"It is classified as non-hazardous in accordance with European Regulation (EC) No 1272/2008 on classification, labelling, and packaging of substances and mixtures.

"The dust is unlikely to remain airborne, and local atmospheric concentrations will remain below any relevant exposure limit values."

The MP said: "Some residents allege they and their offspring suffered with coughs and respiratory issues, which is very concerning. Fallout was visible on vehicles."

He added: "This episode comes on the back of ongoing concerns from residents living near the site about noxious smells and a pollution incident on September 12 impacting Thornton Brook, River Gowy and consequently the Mersey Estuary."

People can report any new, reoccurring or worsening incidents to the Environment Agency 24-hour hotline on 0800 80 70 60.