Unexplained increases in the anion gaps and serum osmolalities were observed in 3 burn patients who died following treatment with a polyethylene glycol-based burn cream. Toxicity due to absorption of polyethylene glycol was suspected after other causes had been excluded. Ethylene glycol was found in the circulation and the 3 patients died in acute renal failure. All the patients were acidotic with increased anion and osmolal gaps. This syndrome was similar to the more common poisoning with ethylene glycol but also included an increased serum calcium with a concomitant decrease in the ionized calcium. The cause of this high 'calcium gap' appeared to be binding of calcium by dicarboxylic acid metabolites of polyethylene glycol. These findings were the same as those found in rabbits treated with polyethylene glycol.