Tests have been carried out at a disused factory after workers complained of feeling unwell.

Traders at Klondyke Industrial Estate, Queenborough, have said “sulphurous smells” have been emanating from the old bottle works plant where the ground is being prepared for a housing development.

Excavations are said to have triggered a number of symptoms, including headaches, sore throats and stinging eyes.

Businessman Ron Knight, who runs Ron’s Low Loader and Son, said: “A lot of people have complained of feeling ill.

“We’ve put it down to sulphur, which the bottles at the old plant were made of.

“We’re only about 20ft away from the bottle works and the smell was really bad a week ago. It was like bad eggs.”

Klondyke traders enlisted the help of Guy Nicholson, Labour’s prospective parliamentary candidate, over fears the aroma could be toxic.

He said: “I raised the issue of the possibility of pollutants being released during excavations with Swale council’s environmental team. They’ve reassured me that monitoring equipment at the site is not registering any pollutants or emissions.”

Mr Nicholson said he remained concerned houses are due to be built on land which had been “subject to hundreds of years of industrial use”.

He said he is due to meet building contractors at the site to voice his views. The derelict plant, along with the soon-to-be vacated Klondyke, will eventually house nearly 1,200 properties as part of Queenborough and Rushenden regeneration plans.

Initially, businesses were given until August to vacate the industrial estate.

In January, it was revealed the Homes and Community Agency was negotiating with the land’s owners for an extension to its notice to quit.

Swale council has been approached for a comment but has not yet responded.