Chinese officials are investigating a chemical plant in the north-east of China after 160 people were hospitalised.
Citing the Beijing Times, Agence France Presse reported that some local residents have also been taken ill.
"Staff at a plant operated by the Jilin Chemical Fibre Group in Jilin city, as well as residents living nearby, started complaining of headaches, nausea, vomiting and general fatigue in late April," the news provider stated.
Patients fear they may have been affected by emissions from the nearby Connell Chemical plant.
The facility has reportedly been ordered to close its aniline plant, while city inspectors monitor
air quality.
According to reports, environmental authorities have not yet been able to identify a specific pollutant.
The Agency for Toxic Substances and Disease Registry defines aniline as a yellow liquid with a characteristic odour, used to manufacture a variety of synthetic dyes and agricultural chemicals.