Apparently the second time this has happened; a salutatory lesson for those in charge of emergency response at the coast.

The Guardian: The chemical cloud that left beachgoers on the East Sussex coastline with stinging eyes, sore throats and even vomiting on Sunday remains a mystery, with officials saying it is unclear what caused the haze or what it was composed of.

Experts have put forward a number of possibilities, ranging from accidental discharges of chemicals at water treatment plants to toxins from algal blooms.

David Slater of the school of engineering at Cardiff University, said the haze appeared to have come from a local source. “From my experience in regulating water companies, unplanned discharges are not uncommon,” he said.

But a spokeswoman for Southern Water said there was no evidence that wastewater works were linked to the haze. “All our sites in the area are constantly monitored and everything is working normally,” she said, adding that chlorine gas was not used at the Eastbourne wastewater treatment works. Click here to read more