The nurses and other healthcare professionals brought in to replace Temple University Hospital's striking employees may owe Philadelphia hundreds of thousands of dollars in wage or business taxes, City Controller Alan Butkovitz said. "The recent job action by local nurses and healthcare workers . . . and your decision to employ HealthSource Global Staffing Inc. to hire replacement workers has raised a number of issues over responsibility for paying all appropriate employee and business taxes," Butkovitz said in a letter addressed to hospital chief executive Sandy Gomberg. Temple had no comment, except to say that it would respond "in a timely and appropriate manner," spokeswoman Rebecca Harmon said.