The UN Special Rapporteur on contemporary forms of slavery, Ms. Gulnara Shahinian, has said more than half of the 215 million children working throughout the world are subjected to the worst forms of child labour, including sexual and labour exploitation. In a statement she issued in New York to mark the World Day Against Child Labour, Ms. Shahinian said one of the most abhorrent forms of child slavery is found in mining and quarrying, where children start work from the age of three.