what organs if injured would cause chemical peritonitis
Chemical (sterile) peritonitis may be caused by irritants such as bile, blood, barium, or other substances or by transmural inflammation of visceral organs (eg, Crohn disease) without bacterial inoculation of the peritoneal cavity.
Plain erect CXR is not always diagnostic, esp. if the abdomen is full of fluid. The patient must be sat up at 90-degrees for at least 10 mins before you do the CXR. If there is doubt CT is far more sensitive. Upper GI perforations (stomach, duodenum) are usually 'sterile', but cause chemical peritonitis.