Residents in the Ellesmere Port area affected by the dust fallout from a nearby refinery on Tuesday are being advised to contact health services if they have breathing difficulties.
What Cheshire West and Chester Council initially described as a 'major fallout incident' from the Stanlow refinery led to a cloud of dust blowing west and dumping its contents on houses and vehicles in the town.
EET Fuels, which owns and operates the refinery, said in a community statement posted several hours after the incident that the dust was "non-toxic and non-hazardous", and "does not pose any health or safety risks".
However, an update from the UK Health Security Agency is advising anyone in the area who breathed in the material and is suffering "respiratory irritation" to contact local health services.
The UKHSA, in a statement, 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."
EET fuels added the source of the dust cloud came from the "unplanned shutdown of a process unit".
The firm's statement on Tuesday added: "We can advise that the source of the dust release has been identified and has been effectively managed.
"The affected unit is currently being restarted and I regret to have to inform you that during this period you may continue to experience increased levels of noise and flaring from the refinery.
"Please be assured that this activity is being undertaken in a safe and controlled manner.
"Supplies of products to our customers will continue as normal.
"For further information or questions, please reach out to Communications@eetfuels.com."
Ellesmere Port and Bromborough MP Justin Madders said he had "received many enquiries" from constituents about the air quality issue, adding he would discuss it with the Environment Agency.
Upon receiving the UKHSA statement, he added he would "continue to press" for more information.
Runcorn and Helsby MP Mike Amesbury said: "Some residents allege they and their offspring were suffering with coughs and respiratory issues on Tuesday, which is very concerning. Fall-out was visible on vehicles.
"I understand most of those affected were in Ellesmere Port and have spoken to my neighbouring colleague Justin Madders MP but gather my constituents living in the immediate shadow of Stanlow were also impacted.
"I have also been informed by the Environment Agency about another episode, just days earlier, on September 12 involving a pollution incident impacting Thornton Brook, River Gowy and consequently the Mersey Estuary.
"I am demanding answers from EET Fuels about the nature of the substances released in both cases and what action has been taken to mitigate any potential harm.
"In both instances, I’m unhappy with the lack of openness and transparency or sense of urgency in letting the community know what had taken place and what was being done about it."
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