The health impact of H2S gas, in industries where the gas is produced as a byproduct and in residential areas where the gas is naturally produced, has been concern for a long time.
Researchers from University of Otago, Wellington, the University of California, Berkeley, and Stanford University monitored the health effects of the gas amongst 1600 adult residents of Rotorua for five years.
People's exposure level to the gas was estimated based on their work and living place and based on it they were divided into four groups from highest to lowest level of exposure.
The findings indicated no significant association between H2S exposure levels and risk of asthma. Moreover, symptoms of asthma were reported less often in highest exposure group.
According to the authors, the results reassuring to those exposed to low levels H2S at both residential and industrial regions.
However, the positive effects of the gas cannot be confirmed based on this study and the researchers are planning to soon examine the effects of H2S on nervous system and the eye.