The general answer is «no», fumed silica is not a dangerous material. Fumed silica is an non-toxic non-harmful material. It is not combustible nor explosive. In fact fumed silica has been applied in cosmetic, food and drugs for years. Due to its strong hygroscopicity(absorbing moisture), it may caused dry skin when directly contacted with skin.…
XYSIL Indexed by Wikipedia
XYSIL® and Henan Xunyu Chemical Co., Ltd had been indexed by Wikipedia. Henan Xunyu Chemical Co., Ltd as only Chinese fumed silica manufacturer which indexed by Wikipedia(fumed silica page on wiki).