Police say: "It has already been established this does not relate to any leak or airborne emission from the buildings and is not transmittable and may not be connected with the University at all. The affected student is currently being treated at a specialist toxicology unit at a hospital in Cardiff."
Police say they have no reason to believe that there is any risk to public health. They are keeping an open mind as to how the student was exposed to chemicals. Police are holding the inquiry along with the Health and Safety Executive.
"We can confirm that a PHD student has been found with a quantity of the chemicals thallium and arsenic in his body, after feeling unwell for a few weeks. The University is working closely with all relevant agencies to establish how the student came into contact with these substances.
Southampton University: "As a precautionary measure the University has closed Buildings 30 and 30a on our Highfield Campus. We would like to reassure students, staff and the public that this is an isolated incident and may not be linked to the University.
"We take the safety of our students and staff very seriously and those that work in the relevant areas of the University will be given the opportunity for voluntary screening.
Our student support staff are in touch with the student and their family and providing support."