Such a large-scale food poisoning incident, resulting in four deaths, is something no one has experienced before.

Zhang Hui’s expression became more serious: "Those with more severe symptoms are in the ICU, the hospital is doing their best to rescue them, but the situation is not optimistic."

"Has the hospital identified which toxin caused the poisoning?"

"They have basically confirmed it." 𝗳𝚛𝗲𝕖𝚠𝚎𝚋𝗻𝗼𝕧𝗲𝐥.𝚌𝚘𝐦

Zhang Hui opened his phone, displaying the blood test results sent from the hospital: "The hospital found TTX in the blood of dozens of poisoned patients!"

"TTX? Fugu toxin?"

Lu Chuan’s face turned very grim!

Fugu toxin is one of the most lethal toxins, 0.5 milligrams can be fatal.

A small fugu fish contains enough toxin to kill 30 adults.

It is said to be more deadly than potassium cyanide, and with the confirmation of fugu toxin, the differing states of death among the two recently deceased individuals now have an explanation.

Fugu toxin affects individuals differently, depending on their physical health.

The toxin mainly attacks the human nervous system, thereby affecting the nervous system’s control over the body’s organs.

Since each person’s nervous system is slightly different, the control over organs also varies.

For individuals with pre-existing conditions, the fugu toxin can trigger and rapidly spread the illness.

Simply put, a healthy person attacked by fugu toxin will experience a gradual cardiac arrest due to inadequate blood supply, leading to death.

For someone with an existing illness, the toxin can trigger the disease and cause it to spread rapidly.

Fugu toxin is not a single toxin but a composite one. Fugu fish do not naturally produce this toxin, but consume algae that contain trace amounts of it, accumulating lethal levels over time.

Therefore, wild fugu will invariably contain high levels of the toxin, but farm-raised fugu, which are fed artificial feed, do not accumulate the toxin and hence are not poisonous.

A construction site is unlikely to serve fugu for breakfast, meaning accidental ingestion of fugu toxin is highly unlikely.

"The action group is already reviewing surrounding video footage to identify the poisoner."

"The cafeteria’s inspection is entrusted to you."

Lu Chuan understood Zhang Hui’s intentions, realizing that intentional poisoning could occur in two ways: on-site or within the ingredients.

Fugu toxin only loses activity at temperatures above 220 degrees Celsius; typical frying and sautéing may reach these temperatures locally but rarely comprehensively.

As for steaming or boiling, these methods entirely fail to deactivate the toxin.

This is why wild fugu remains toxic even after being cooked.

Fortunately, fugu toxin is not contagious; it only causes toxic reactions when metabolized into the bloodstream through ingestion.

Lu Chuan began collecting leftover breakfast foods and unused raw materials from the construction site.

These items need to be quickly analyzed to pinpoint the ultimate source of the fugu toxin.

This poisoning case was Lu Chuan’s first, but from his professional perspective with intermediate Crime Scene Investigation skills, collecting evidence was not difficult.

Up to this point, the busiest were the action group members, as surveillance was limited to exits on the construction site.

The construction site is usually well-managed; entry requires ID swiping.

However, this management only applies to construction personnel, not to logistics staff.

Cafeteria supplies do not enter through the main construction gate, but through a side entrance.

There are no surveillance cameras here.

The head chef in the cafeteria was being questioned.

"I’ve only heard of fugu, never seen it, and our cafeteria could never afford it."

The construction site’s head chef was not a professional chef.

"I got this cafeteria contract through my brother-in-law’s connections; the requirements are simple, just cook three meals a day."

"We buy bread outside for breakfast, make a pot of vegetable soup, and serve some pickles; nothing else."

"Do your food supplies have inspection certificates?"

"Yes, all our meat comes from certified sources with inspection stamps; the vegetables are bought from the market just left of the construction site, 300 meters from the exit."

"Who is in charge of procurement?"

"I make arrangements with the vegetable vendor to deliver items every morning."

"You don’t suspect me of poisoning them, do you?"

The chef shook his head vigorously: "I have no grudge against the workers; they pay to eat, and I’d rather they stay healthy and keep coming back. Why would I poison them?"

"We haven’t accused you of poisoning. Don’t be nervous. No matter who did it, we will find out. Just cooperate with our investigation."

"Oh, oh, I’ll cooperate for sure!"

If it were common pesticide residue or poisonous plants or animals, the cafeteria manager would undoubtedly be liable.

However, fugu toxin is unlikely to enter naturally, making intentional poisoning almost certain.

In this scenario, the cafeteria’s liability is minimal.

After all, they couldn’t possibly detect fugu toxin.

"How many were involved in preparing breakfast today?"

"Just me, breakfast is straightforward. The bread was delivered this morning, and the vegetables were washed, cut, and boiled."

"No outsiders came in?"

"No, none."

With no outsiders entering, and the chef lacking motive, the likely issue originates from the source.

The interrogator reported the situation to Zhang Hui and shared their suspicions.

"Currently, it seems likely that either the bread or the vegetables are the issue."

"According to the manager, he’s worked with the bread and vegetable suppliers for a long time, since the project began."

"This makes it unlikely they would poison, as they lack motive. However, could there be competitors?"

"You’re suggesting commercial rivalry?"

"Or perhaps they have enemies. These are possibilities, but more investigation is needed."

Zhang Hui nodded; this was certainly a plausible angle.

Of course, it’s also possible that the cafeteria manager has enemies seeking revenge.

The cafeteria’s monthly profit is considerable, and given the manager secured the deal through connections, it’s plausible that rivals might devise such retaliation.

Every possibility remains open.

After Zhang Hui reported the situation to Qin Yong, the action group split into two teams.

Sun Jun’s team was tasked with investigating bread and vegetable suppliers, while Zhang Hui’s team looked into the cafeteria manager’s social connections.