Document doc = new Document(PageSize.A4.rotate());

while(iteratorRow.hasNext()){

Object valorCelulaRow = iteratorRow.next();

if(valorCelulaRow != null){
 Paragraph p = new paragraph ();
 p.add (valueCellRow.toString ());

 doc.Add ((Element) p);
 doc.Add (p); //ERRO AQUI
 }
}