Giant Hogweed is deceptively dangerous - it looks like a big weed, but its sap is highly toxic to the skin

NATURE experts are urging vigilance after a schoolgirl suffered third-degree burns from a toxic giant hogweed plant.

The weed – which grows up to 5ft tall with a large white flower on the top – is prevalent in Fingal and the council is on standby to destroy any that are reported.

The giant phototoxic plant grows by rivers and contains a poisonous sap that reacts with the skin, forming painful blisters.

In extreme cases, these can swell to the size of a fist and cause scarring which may require plastic surgery.

Fingal County Council said the plant had been found along the Sluice, Tolka, Ward, Broadmeadow and Mayne rivers, as well as at Howth Head, Santry and Dunsink.

A council spokesperson told The Gazette: “It looks like very large cow parsley but it is considered to be a serious and significant danger to public health.”

Last week, Baldoyle Nature and Wildlife Society posted about the plant – Haracleum mantegazzanium – and urged vigilance.

Giant hogweed was spotted in the area last year but safely removed and a spokesperson for the society urged people not to panic or confuse the toxic plant with harmless native hogweed.

Crumlin mum Lorraine Jewell last week warned others to be vigilant after her teenage daughter Ellie had to be treated in hospital for third-degree burns.

Dr Mike Williams, a professor of botany at Trinity College Dublin, said: “The sap of the giant hogweed plant is toxic to skin. Severe burns and blisters form and can take months to a year to heal. I’ve seen people have the scars years later.”

Fingal County Council said it had been undertaking control measures at a number of sites since 2010 – but that the seed remains viable for seven years, so the same sites have to be revisited for that length of time in case new plants germinate.

A council spokesperson said: “The reaction can occur by individuals accidentally brushing past leaves and can be especially acute in children.

“If anybody spots giant hogweed plants which would be in flower at the moment, please send your record to biodiversity@fingal.ie.”