Grand Canal green stain substance identified

(ANSA) - ROME, MAY 29 - The substance that stained Venice's Grand Canal bright green Sunday has been identified, experts said Monday.
    The culprit behind the bizarre event, which fascinated tourists and residents alike and which climate protest groups disowned, has been named as fluorescein, a contrast agent most commonly used for diagnosing eye complaints.
    Venice police said Monday no avenues of investigation had been ruled out n the case, which recalled a piece of performance art by an Argentine artist at the Biennale in 1968. (ANSA).