Some of British artist Damien Hirst’s most famous pieces, involving dead animals being preserved in glass tanks, leaked dangerous levels of formaldehyde gas during a show at London’s Tate Modern gallery four years ago.

Researchers writing up a study in the journal ‘Analytical Methods’ claimed that scientists were testing a new sensor for the remote detection of various carcinogens, and found that in the 2012 exhibition at the Tate Modern – the most popular tourist destination in Britain with nearly six million visitors a year – levels of formaldehyde were significantly higher than the maximum allowed by legislation.

Damien HirstDamien Hirst pictured in 2014

“It has been found that the tanks are surrounded by formaldehyde fumes, constantly exuded in the atmosphere (likely via the sealant), reaching levels of 5 ppm (parts per million), one order of magnitude higher than the 0.5ppm limit set up by legislation,” the abstract of the article states.

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One piece that was found to have emitted high amounts of the dangerous gas was a 1994 piece showing a lamb preserved in a formaldehyde solution and a glass and steel box. The famous 1993 piece ‘Mother and Child Divided’, which contained a calf and a cow each bisected and put in four such boxes, also reportedly exceeded the amount allowed by the law.

The gas is known to be harmful to some individuals even at 0.01 level (50 times lower than the legal maximum), causing wheezing, coughing and nausea, with some studies suggesting it can even cause cancer with long-term exposure.

Damien HirstThe 1994 piece of art in question

“Tate always puts the safety of its staff and visitors first, and we take all necessary precautions when installing and displaying our exhibitions,” a spokesperson for the Tate Modern said in a statement in reaction. “These works contained a very dilute formaldehyde solution that was contained within sealed tanks.”

Hirst’s representatives have not yet commented on the study, conducted by the Politecnico di Milano in Italy, at the time of writing.

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