The gas leak from LG Polymers, which led to the death of at least seven people in Visakhapatnam, is suspected to have been caused by styrene gas.
The most common health problems when exposed to styrene involve the nervous system — both the central and the peripheral nervous systems.
According to the Atlanta-based Centers for Disease Control and Prevention (CDC), the health effects due to inhalation of styrene gas include tiredness, feeling drunk, slowed reaction time, concentration problems, balance problems and changes in colour vision.
The styrene concentrations that cause these effects are more than 1,000 times higher than the levels normally found in the environment.
According to the U.S.-based Environmental Protection Agency (EPA), short-term exposure to styrene can lead to respiratory effects, such as mucous membrane irritation, eye irritation, and gastrointestinal effects. Chronic exposure can cause effects in the central nervous system with symptoms such as headache, fatigue, weakness. It can also cause central nervous system dysfunction including memory, visuomotor speed, hearing loss and peripheral neuropathy.
Clinical studies of volunteers and workers exposed to styrene have demonstrated both the central and the peripheral nervous systems toxicity.
The number of studies of styrene clinical neurotoxicity is rather small. Acute exposure to styrene via inhalation at 376 ppm for 25 minutes had resulted in nausea, a sense of inebriation and headache. But no studies have been carried out to understand the harmful effects from exposure at extremely high concentrations lasting a couple of hours.
Currently, no studies have reported deaths from short-term exposure to styrene gas. Hence, it is not clear if the deaths were caused by styrene gas or some other chemical or a combination.