Abstract toxicity from polychlorinated biphenyls (PCB’s) and combustion products. A 42 year old previously healthy white female, worked as a, “lineman”. The patient was dispatched to re-establish electrical connections following a transformer fire. The transformer was insulated with known PCB’s. The patient worked inside the transformer for a period of three days fixing the internal electrical circuits. By the middle of the third day, the patient developed shortness of breath with new onset of wheezing accompanied by a macular rash on the face. The patient was immediately taken to a hospital and treated with intensive therapy for about five days for shortness of breath, rash and a new onset of diarrhea. She was then placed on a regimen of continued treatment for the new onset of reactive airway dysfunction syndrome, macular rash (porphyria cutanea tarta). GI distress and the diarrhea continue. The patient was seen by toxicologists approximately three months after the exposure. Urine PCB levels were negative, however, a fat biopsy showed PCB levels to be that of 87.5 ng/ml (pcb) with a detection limit of 10 nanograms per ml. No chloro dibenzo furans nor chloro dibenzo dioxins were identified in the fat biopsy. Over the following two years, the patient continued to have more episodes of macular rashes, urticaria, wheezing and diarrhea with new onset of documented decrease in neurocognitive function. The patient then developed new onset of hypertension. The rash extended to that of severe perineal moniliasis and then was started on antifungal therapy. Children born to mothers exposed to PCB’s can develop neurobehavioral dysfunction. PCB’s are known human teratogens and are capable of affecting the offspring of women exposed in their child-producing years. The IDLH (Immediate Dangerous to Life or Health) concentrations of PCB’s containing 42% to 54% chlorine is known to be 5 mg per meter squared. Additional toxicity is caused by the myriad of decomposition products in transformer fires.