A factory official and an owner of a Shanghai-based delivery service franchise are being held by police after packages tainted with a toxic chemical killed one man and sickened seven other people.

The incident triggered a nationwide order from central authorities for postal and courier services to strengthen checks on package contents before they accept them. Anyone not following the rule would have their license revoked.

Liu Xingliang, a resident of Dongying City in east China’s Shandong Province, suffered methyl fluoroacetate poisoning after he accepted a package delivered by Shanghai YTO Express in late November, according to the Shandong Post Bureau.

The bureau said four parcels delivered by the company were contaminated with methyl fluoroacetate, a toxic liquid widely used in the pharmaceutical industry.

A package containing the chemical had been sent from a chemical plant in Jingmen City, Hubei Province, to a pharmaceutical plant in Weifang City in Shandong on November 28.

During transport, the package was damaged, and the leaked chemical poisoned five delivery workers and two recipients in Shandong’s Shouguang and Jiaozhou cities, in addition to the victim in Dongying.

Shandong police said yesterday they were holding the deputy director of Jingmen’s Xiongxing Chemical Company, surnamed Yang, on charges of “posing a threat to public safety.” The company has been ordered to suspend operations.

Police said Yang had asked YTO Express to send about 25 kilograms of methyl fluoroacetate samples packed in blue plastic bottles to a client company in Shandong on three occasions in November.

The poisoning cases happened during the third delivery.

“We normally deliver the toxic material ourselves if the amount is over a ton, but this time only a small amount was needed, so Yang called courier firms,” Huang Shenyong, a senior official with the chemical company, told police.

Two courier firms in Hubei and Shanghai-based STO Express had refused to deliver the toxic material when Yang called them, but YTO accepted, Huang said.

“Yang has been feeling regretful after the casualty happened and the company has asked him to cooperate with the police in their investigation,” Huang said.

One of the owners of the YTO franchise in Hubei’s Shayang County that received the tainted parcels is also being held by police and the franchise’s business license has been revoked.

Meanwhile, YTO’s franchise in Weifang was ordered to pay a 28,000 yuan (US$4,611) fine for its delay in reporting the incident. Five of the company’s employees showed signs of being poisoned, but the company isolated the five without informing the local postal administration before going on to deliver other packages on the same train on November 29. It reported to Weifang’s postal bureau the next day.

On Saturday, YTO issued a public apology through its official weibo account, saying it was sorry to the victims and their families.

A YTO spokesman said on Saturday that the contamination happened after a package containing the chemical leaked during transport. The chemical plant had claimed it was “innoxious,” or not harmful to health, YTO said. He said that before accepting the package, company staff had performed routine checks “according to company rules.”

In a statement issued to media, the company said it would not shun its responsibilities and was cooperating with the police investigation.

China’s delivery sector witnessed massive growth in recent years thanks to the popularity of e-commerce, but experts say the booming business belies problems such as lax supervision.