sodium bromate and potassium bromate are strong oxidants that are widely used in hair permanent wave neutralizers , reagents of printing or dyeing and other chemical processes . hair wave permanent neutralizing solutions typically contain 2 - 10% sodium or potassium bromate , which are colorless , odorless and tasteless . clinical manifestations of bromate intoxication include vomiting , diarrhea , central nervous system symptoms , oliguric or non - oliguric acute renal failure , hemolytic anemia , and deafness . hearing impairment is rather common and is usually rapidly progressive , bilateral , and of severe to profound sensorineural type of hearing loss ( snhl ) . although many investigators have studied the characteristics of hearing impairment , cochlear implantation ( ci ) after bromate intoxication has been rarely documented . we hereby present a case of successful ci in bromate - induced bilateral sudden total deafness . she had accidentally ingested a cold wave neutralizer . within one hour after the ingestion , she developed nausea , vomiting , and diffuse abdominal pain . her past history included hypertension , left hemiparesis due to previous brain hemorrhage and infarction and depressive disorder . upon arrival in the emergency room of a local hospital , she received intravenous hydration and furosemide injection . one day later , she was referred to our hospital with decreased urinary output and reduced mental state . four days after admission , her kidney function was normalized and mentality was recovered to an alert state . 1b ) and v - wave was not detectable at 90 db in the auditory brainstem response . she was diagnosed as having bromate - induced sudden deafness and steroid was administered systematically for a week with tapering for another week . nucleus 24re was implanted without any intra - operative problems and the neural response telemetry showed satisfactory values . six months after the implant , ci - aided pta showed a threshold of 30 db ( fig . , she comprehended 70% of the sentences , 85% of the words and 68% in the korean version of the central institute for the deaf test . hearing problems may be diagnosed with a delay after bromate intoxication due to other life - threatening symptoms such as acute renal failure which generally occurs within 1 hour after the ingestion . however , the onset of bromate - induced hearing loss is actually rapid , occurring within 4 - 16 hours of ingestion . like many other ototoxins , the degree of hearing impairment is severe to profound , and is irreversible in most cases . since they are usually transient , loop diuretics including furosemide are ototoxic in themselves . in the present case , the patient received furosemide during the primary treatment , which may have aggravated the ototoxic effects of bromate . previous studies using guinea pigs and sodium bromate demonstrated severe collapse of the reissner 's membrane , hair cell degeneration and damage of the stria vascularis . the ototoxicity may be ascribed to a decrease in enzyme activities which leads to damage of the stria vascularis with degenerative changes in outer hair cells on the other hand , dizziness associated with bromated - induced vestibulotoxicity is not common . the dizziness could be secondary to other systemic toxicities such as lightheadedness or general malaise . to our knowledge , there has only been one report in the english literature of ci performed in patients deafened due to bromated - ingestion . in this case , the diagnosis of hearing loss was delayed for at least 6 months after bromate ingestion . in our case , deafness was diagnosed right after the recovery of consciousness and the intervention with ci was done 3 months after the diagnosis . in both cases , the outcome of ci was good . other potential drugs with ototoxicity should be avoided and early monitoring of hearing level is needed .