ESSEN (AP).- The Emscher river in western Germany’s The Ruhr region was one of the country’s most polluted for decades, so bad that parents spooked children with warnings they could die if they fell into the poisonous stew of sewage and chemical waste. Today, a much-cleaner Emscher is the backdrop to more than 20 new art installations — the latest European effort to transform blighted industrial areas into cultural destinations for tourists and to breathe new life into the region. All over the region, around 1,000 former industrial structures have been turned into cultural venues, among them Dortmunder U, a former brewery that has become a gallery, and Zeche Nordstern, a former coal mine that was turned into office space and a museum for model railroads. There are more than 100 theaters and dozens of concerts and musical