Laboratory tests...have found that five in nine Czech school products contain a high share of toxic substances known as phthalates. Items tested at the request of the Czech environmental NGO Arnika included pencil cases, exercise book jackets and erasers, which present a risk if put under mechanical stress or chewed...Czech and EU laws limit phthalates in toys...they do not take into account school products...Jindřich Petrlík, a specialist at Arnika [said], “...There are six of 40 phthalates which were considered to be harmful and dangerous to health...They also have harmful effects on the endocrine system...neurobehavioral development and also have adverse effect on the kidneys...”...“...[S]ome companies changed production to phthalates-free...Koh-i-noor, for example has said all its new products are without the substances.”