Exposure to reduced sulfur gases impairs neurobehavioral function

Area of Science:

• Toxicology
• Neuroscience
• Environmental Health

Background:

• Historically, acute hydrogen sulfide (H2S) exposure was linked to fatal outcomes and permanent brain injury from nonlethal doses.
• This study investigated the long-term neurobehavioral effects of H2S exposure in individuals experiencing exposures ranging from moments to years.

Purpose of the Study:

• To compare the persistent neurobehavioral effects of hydrogen sulfide (H2S) exposure in subjects 2 to 22 years after exposure.
• To quantify the extent of neurological and psychological impairments resulting from H2S exposure.

Main Methods:

• Employed neurophysiologic and psychologic tests to assess mood and symptom frequencies in 16 subjects.
• Compared functional outcomes and symptom frequencies against an unexposed population, adjusting for demographic and educational factors.

Main Results:

• 31 out of 33 assessed symptoms showed elevated frequencies post-exposure.
• Significant impairments were observed in balance, reaction times, visual field performance, color discrimination, and hearing.
• Psychological assessments revealed cognitive disability, reduced psychomotor speed, memory deficits (verbal recall and remote memory), and abnormal mood status.

Conclusions:

• Hydrogen sulfide (H2S) exposure leads to persistent and widespread neurobehavioral impairments.
• The findings underscore the critical need for avoiding H2S exposure to prevent long-term neurological damage.