Phe

A site owned by the pharmaceutical company GlaxoSmithKline, in west Harlow, was purchased by PHE for £30m to get the ball rolling in 2017.

Prof Hopkins, who served as PHE’s chief Covid adviser before moving across to UKHSA, told the inquiry that FFP3 masks offered a high degree of protection in laboratory studies, but the real-world benefits were less clear-cut.

Asked about the December 2020 IP Cell minutes, which suggested PHE was pushing behind-the-scenes for the wider use of respirator masks in healthcare, Prof Hopkins said that was a "really challenging time" in the pandemic with the UK about to enter a third wave of the virus.

Exposure to liquid or gaseous chlorine may cause irritation or burns to the skin and eyes, says PHE.

Exposure to cyanide salts can cause headache, nausea, dizziness, nervousness, confusion, changes in heart rate and drowsiness, according to PHE.