Chlorine

Descriptions of deaths from chlorine were made after the gassing of allied soldiers at Yepes in the first World War. Follow-up in 1933 showed neurobehavioral toxicity from chlorine. Since that time doubt has been cast on toxicity. Chlorine causes acute pulmonary edema and obliterative bronchiolitis.

A spill provided the opportunity to study the effects of chlorine in about 100 people. Ninty-seven residents exposed seven weeks earlier were compared to 202 adults and 135 children who were unexposed to chemicals. The 81 adults ages ranged from 18-63 years, mean 38.4 years and 16 children were ages 8 to 17 years.

The battery of neurophysiological tests assessed balance, blink reflex latency R-1 (BRL R_1), visual fields, 17, color discrimination, grip strength and psychological tests: pegs in pegboard, trail making A and B fingertip number writing, Culture Fair, vocabulary, information, picture completion, similarities, verbal recall and profile of mood states (POMS) scores. Comparisons were made as percent predicted which adjusted for age and other factors.

The exposed adults had abnormal visual fields often constriction or multiple quadrant defects, abnormal hearing, abnormal balance with eyes closed, abnormal BRL R-1, elevated finger writing errors, verbal recall immediate and delayed and POMS score. Children had abnormal blink BRL R-1 visual fields and POMS scores.

Adverse effects of chlorine on the central nervous system (CNS) were measured seven weeks after exposure. Follow-up studies will evaluate the rates of deterioration of various functions using patients as their own controls.

Fourteen exposed patients, a convenient sample, were compared as percent predicted to national unexposed subjects for balance, blink reflex latency R-1, reaction time, visual fields, color discrimination, hearing and cognitive, recall, memory, perceptual motor speed and mood status.

Exposed subjects had impaired balance with eyes open and eyes closed, simple and choice reaction time, blink reflex delay, decreased hearing and grip strength, cognitive (digit symbol and vocabulary), pegboard, trail making A and B, verbal recall without impairment of remote memory. Abnormal mood states were elevated as were frequencies of 28/35 symptoms. Forced vital capacities were reduced.

Conclusion: A single breath to a few hours chlorine exposure indoors and outdoors impaired neurobehavioral function. Exposures must be avoided to prevent injury.

Several patients in the neighborhood of a chemical plant's chlorine leak developed disturbed balance, slowed reaction time and losses of segments of their field of vision, that is blind spots or scotoma, delays of the blink reflex and impaired recall-memory. Another patient, was squirted in the face when tubing erroneously filled with chlorine broke loose. He had progressive loss of vision, impaired balance, seizures and poor memory and recall to the point of being lost in familiar places.