By staff reporters Li Hujun, Yang Yue and Liu Jingjing

(Caijing Magazine)More than 1,000 workers at the Jilin Chemical Fibre Group Co. Ltd. in the northeastern city of Jilin reported dizziness, nausea and other symptoms during a three-week health crisis that so far has defied clear explanation.

At least 161 workers were hospitalized as health woes rippled through the plant's labor force between April 23 and May 12.

Some workers blamed a gas leak at the neighboring Jilin Connell Chemical for a "mass poisoning." On April 30, local government ordered the plant to elevate the height of its waste gas emission system and further away from Chemical Fibre to reduce the monoxide density in the close neighborhood.

At some point during the investigation, the State Administration of Work Safety also alerted other manufacturers to "draw lessons from the gas leak accident at Jilin Connel Chemical" in a notice published on its official website on May 18 but the quoted sentence, which ran contrary to the judgment given previously by a team of Health of Ministry experts, was axed the next day without an explanation.

The team, led by researcher Zhang Shoulin from the National Institute of Occupational Health and Poison Control under the Chinese Center of Disease Control and Prevention, offered a different interpretation after the wave of illness. Based on a four-day investigation in Jilin, they told journalists at a briefing organized by the Jilin municipal government May 14 that the workers were basically victims of a psychogenic disorder --  mass hysteria -- and not toxic chemicals. 

Since then, all workers receiving treatment at the Jilin Occupational Disease Hospital have been discharged or transferred to other hospitals. 

A Caijing investigation found that a similar spate of sickness last September, the death of a Connell worker in April, and questions about the plant's waste gas discharge system have contributed to a lingering cloud of suspicion among employees at Jilin Chemical Fibre.

Forty-year-old Jilin Chemical Fibre is a former state-owned company later revamped as a joint venture. Connell is an enterprise started by a Hong Kong concern that's now dominantly state-owned. The plants are on opposite sides of a street in an economic and technology zone in northwest Jilin.

Each company partially owns the other. Moreover, they are linked through shareholders, ties to the local government, and top executives.

Connell is potentially the country's biggest producers of aniline, a chemical used for dyes, drugs and other products. Its production line opened in early April.

After the health incident began, the Connell plant shut down for four weeks. It later restarted. But life at Jilin Chemical Fibre has yet to return to normal.