Chapter 72 Fighting Fire with Fire

Chapter 72 Fighting Fire with Fire

Chapter 72 Fighting Fire with Fire
Du Yu said: "Both cups are poisoned, so the wine must be poisoned."

The laboratory technician said, "Captain Du, we have tested the bottle of wine and it is not poisonous."

Du Yu heard this and said, "So the [cleaner] poisoned all the cups? That way, Song Lang wouldn't have picked up the wrong cup."

After saying this, he frowned. If this was true, it would be an extremely serious poisoning incident.

If the nightclub hadn’t closed last night, many people might have died!
The more he thought about Du Yu, the more scared he felt, and the more pressure he felt.

The police are not gods. Even if the Jiangcheng police work 24 hours a day and can prevent % of homicides, they cannot prevent potential poisoning crises.

There are many examples of foreign presidents and top businessmen being assassinated. When the enemy is in the dark and we are in the light, there will always be negligence. Moreover, poisoning is more covert and easier to escape than using weapons.

The analyst explained, "We also tested the other empty cups and found nothing. In fact, only the two cups that had been filled with wine were poisonous. It's not that all the cups have problems."

Du Yu was stunned. "Only the two cups used by Director Xu and the deceased were poisoned, but the wine was fine? How did the murderer know for sure that they would use those two cups?"

In an instant, a crazy idea flashed through his mind.

It wouldn’t be Song Lang himself who poisoned the person, right?
Zhou Shi didn't bother to discuss these, but turned to look at Xu Yiqing, with a worried look on her face: "Are you okay? Let's go to the hospital."

Xu Yiqing shook his head: "More than ten hours have passed. If I were going to die, I would have been lying in the next room with Song Lang, and Ah Sheng would have dissected me with a sad face."

When Lin Sheng heard this, his expression suddenly fell. Brother Xu was both a teacher and a friend to him. If something really happened to him one day, he would be very miserable.

"Brother Xu, please don't say such unlucky words. I'm really worried that something bad will happen to you."

Xu Yiqing was relieved to see that his face was really full of worry, and decided not to make such jokes anymore.

Zhou Shi was still worried: "You said that with the toxicity of aconitine, Song Lang would die within half an hour, but he still had an attack two hours later... Just in case, it's better to go to the hospital for a check-up."

The laboratory technician replied at the right time: "In fact, the poison found in the test is somewhat different from the composition of aconitine."

Du Yu touched his forehead, feeling troubled: "Now even the poison in the cup is different from the poison analyzed by your Director Xu?"

He believed in Xu Yiqing's judgment, so he did not suspect that the autopsy was a mistake.

Xu Yiqing also looked at the laboratory technician. How could it be possible that even the poison was wrong?
There will be no problem with Song Lang's blood test. After all, the blood was drawn from the heart of the deceased and cannot be faked.

The laboratory technician knew that everyone had misunderstood and quickly said, "It does contain aconitine... but it is not just aconitine. Because it is mixed with some other things, all the indicators are abnormal. Director Xu, please take a look at the report. Our laboratory department's opinion is that the aconitine is impure or it is a complex toxin."

He was just a small clerk in the Forensic Department... In fact, it's not just in the Forensic Department, it's the same everywhere, the final decision is made by the leader, and the people below are only responsible for stating the facts.

Although Lin Sheng is now the one in charge of the Forensic Department, everyone knows that Lin Sheng has too little experience, so even if Xu Yiqing is only a nominal consultant after his resignation, everyone still has to listen to him.

"I see. I'll see."

"Then I'll be busy now. Call me if you need anything."

Xu Yiqing turned on the office computer and found the report document just sent by the laboratory department in the office software.

Du Yu also leaned over to take a look. At first glance, this report looked a bit like his own physical examination report. After the blood test, there would be these indicators that he couldn't understand. As for where the abnormalities were and what caused them, he would have to make an appointment to ask the doctor.

It doesn’t matter if you don’t understand it. Xu Yiqing can be said to be omnipotent when it comes to forensic identification.

"It can't be wrong. Although some of the data are not very obvious, it should be aconitine." Xu Yiqing said: "Aconitine is very easy to hydrolyze. There was liquid left in the glass after drinking last night. After more than ten hours of hydrolysis, it is normal that the data is not obvious. It's just..."

Xu Yiqing called Lin Sheng: "Asheng, come and see, in addition to aconitine, there are other abnormal data for other compound components. What do you think it is?"

Lin Sheng scratched his head and began to rack his brains to recall the pathology knowledge he had learned before.

"The histidine content is relatively high. Histidine is also a type of alkaloid... Is it some kind of neurotoxin? However, this type of toxin is a nitrogen-containing ring structure, which is generally stable and will not hydrolyze or dissolve in heat. There is no situation where the content decreases over time. So just looking at the dosage in the report, let alone killing people, the most you will feel is a numb tongue and slurred speech."

Xu Yiqing frowned: "Neurotoxin, aconitine, the onset of poisoning was delayed for several hours..."

He felt like he was about to catch something.

During his graduate studies, Xu Yiqing was always the one who studied the most seriously. He rarely went out for fun or played games in his spare time. He spent most of his time in the library, reading typical forensic cases from ancient and modern times, both at home and abroad.

He seemed to have seen this situation somewhere before...

Yes, there must be similar cases. Xu Yiqing believes in his memory.

"Let me look up some information." Xu Yiqing said, "I'm not as smart as you. Why was the cup poisoned but Song Lang died while I was fine? I'll leave it to you to figure out. I'll focus on investigating what I'm good at."

After that, he opened the Baidu interface and tried hard to think about the books and cases he had read at that time.

It was ten years ago that I started my postgraduate studies.

No matter how good your memory is, it is difficult to remember the specific content of a book you read ten years ago.

"Why did the test result show aconitine and another neurotoxin in the cup, but only aconitine was detected in Song Lang's body?"

While muttering, he entered the two keywords "aconitine" and "neurotoxin" into the search bar and began to read news reports over the years.

Time passed by minute by minute. Zhou Shi and Du Yu were discussing all the details of last night. Lin Sheng was listening silently beside them. Occasionally when asked, he would offer some opinions from the perspective of an observer, but most of the time it was just the two of them discussing.

Or to be more precise, it was Zhou Shi's analysis, and Du Yu nodded as he listened.

Zhou Shi began to pace in the office again. She closed her eyes and put herself in the murderer's shoes, profiling possible scenarios.

In the blink of an eye, it was already noon. The other three people discussed for nearly an hour, and Xu Yiqing read the materials for an hour.

Suddenly, an idiom that appeared in the keywords of the web page caught his attention.

Fight fire with fire!

"This is it!"

Xu Yiqing showed a look of joy. He clicked on the web link and clenched his fists as he looked at the news report inside: "Found it, come and have a look."

The other three people came over to watch. Du Yu looked at the news headline and murmured, "Japan's most talented serial killer, three wives died of myocardial infarction?"

Lin Sheng discovered the blind spot and said, "Myocardial infarction, the same way Song Lang died."

Zhou Shi looked at the time when the case occurred in the report: "1986, a case from the last century."

Xu Yiqing said: "Because of the long time ago, the technology was not developed decades ago, so many poisons could not be tested at that time. In addition, Japan's forensic identification has limitations. The autopsy needs to obtain the consent of the family members, otherwise the police have no right to dissect the deceased, so many cases are spread out in a mysterious way."

After a pause, he continued, "In fact, this case is very simple. The cause of death is aconitine poisoning. The husband killed his wife to defraud insurance and forged his alibi... Because aconitine poisoning takes at least five minutes and at most half an hour to take effect, and his wife died two hours after the husband gave her the medicine, there is insufficient evidence to convict her."

In 1986, husband Riki Kamiya and wife Kurisako traveled together with three of their wives' close friends.

On the way, the husband flew back home on the pretext of an urgent company matter, and before leaving, he forced his wife to take a so-called vitamin pill.

Two hours later, when the wife was playing with her friends, she suddenly opened her eyes wide, knelt on the ground with her hands covering her chest, had a painful expression, sweat broke out on her head, and her face turned pale.

The friend was terrified and quickly called the emergency number, but before the ambulance arrived, his wife had already died.

From the beginning of discomfort to death, it only took five minutes!

The death report issued by the hospital was a natural death caused by myocardial infarction. My friend insisted that the husband poisoned his wife, after all, anyone would think that the pill was problematic.

However, due to the limited technology at the time, it was impossible to detect any neurotoxin residues in the deceased's body. The case was not overturned until four years later by a professor.

The professor in charge of the autopsy at the time retained 30 ml of the deceased's heart blood. After technological iterations, the component of aconitine was detected, thus confirming that the wife was murdered by her husband rather than died of natural causes.

After listening to Xu Yiqing's summary, everyone present understood something.

"It's very similar to Song Lang's death."

"Died from aconitine poisoning, but the onset of the poison was delayed by two hours."

Zhou Shi asked: "Since the report can be written, it means the case must have been solved... How did my husband do it?"

Xu Yiqing pointed to the four words on the screen.

Fight poison with poison.

"The police found out that the husband had purchased a lot of Aconitum chuanxiong potted plants some time before the trip. In order to conceal his tracks, he did not choose to buy ready-made aconitine poison, but instead extracted it from Aconitum chuanxiong himself," said Xu Yiqing. "In addition, the police also found out that he had bought a thousand pufferfish."

Because her husband is a businessman and puffer fish is an expensive ingredient, such a large order did not arouse the store's suspicion.

Lin Sheng suddenly realized: "The other abnormal value in the wine glass test report just now is pufferfish toxin!"

Tetrodotoxin, referred to as TTX.

It is a widely distributed and most easily accessible alkaloid neurotoxin in nature, and is also one of the most deadly toxins considered by humans to date.

Xu Yiqing said: "Like aconitine, tetrodotoxin is also a type of neurotoxin. Its lethal mechanism in the human body is to block the flow of sodium ions, causing paralysis of the nervous system, and then causing heart disease. Because it acts on the nervous system rather than directly causing organ failure, it is very hidden."

Du Yu thought for a moment and said, "You mean, the [Cleaner] gave Song Lang two kinds of poisons, and these two poisons... well, how should I put it, the properties of the drugs conflict with each other, which greatly delayed the onset of the disease?"

"You can understand it this way." Xu Yiqing said: "Let me put it simply. Aconitine and tetrodotoxin affect the influx of sodium ions and the outflow of sodium ions respectively. Only when the sodium ion concentration is unbalanced will it cause nervous system disorders. But when the two toxins take effect at the same time, the sodium ion concentration is in a dynamic balance, neither too much nor too little, so everything is normal."

"Because the decay period of tetrodotoxin in the human body is much shorter than that of aconitine, when the tetrodotoxin is exhausted and aconitine begins to take effect, two hours have passed since the poison was taken, and the symptoms manifested are death from aconitine poisoning and cardiac arrest."

Whether it is aconitine or pufferfish poison, ingesting just a few milligrams will cause poisoning and death, and even gods cannot save you.

But being poisoned by these two poisons at the same time can allow the deceased to live for two hours without any worries.

Xu Yiqing's expression was solemn. The [Cleaner] was even better at killing people than he had imagined!
And she must be a highly educated person, with knowledge in various fields at her fingertips, including chemistry, pharmacology, counter-reconnaissance, and even camouflage.

He is also very skilled and may have served in the military abroad. He is ruthless and extremely dangerous!

Du Yu and Zhou Shi both showed expressions of sudden enlightenment.

Only Lin Sheng was in deep thought.

"Brother Xu, the low aconitine content in the test report can be understood as hydrolysis after more than ten hours. But tetrodotoxin is very stable and can only be degraded in a weakly alkaline environment. The reported content is even lower than aconitine. Can it really offset the drug's effects for two hours?"

Wine is weakly acidic, and the remaining wine in the glass will definitely not provide a space for pufferfish toxin to degrade.

Mr. Lin firmly believes this.

Logically speaking, the content of various components of pufferfish toxin in the test report of the wine glass should not be so low.

Xu Yiqing laughed and teased him for not taking it seriously: "You are far from being serious if you don't read the report carefully, Ah Sheng."

He moved the mouse and clicked on the report just sent by the laboratory. He pointed to the table and said, "The pH value of the liquid sent for inspection is 8.2. You should remember this basic information after just one look. This is the basic skill of forensic medicine... The wine we drank last night was weakly alkaline."

Currently, most of the wines on the market are weakly acidic, but in recent years, weakly alkaline wines have also quietly appeared.

The human body's pH environment is alkaline, and alkaline wine is more suitable for the human body, reducing the burden on the liver and preventing calcium loss.

In order to highlight the taste of bitter almonds, Song Lang used alkaline wine as the base for last night's cocktail. At the same time, the pH value of the ground almonds is between 7.5 and 8.0, which is also alkaline, resulting in an alkaline environment for the wine remaining in the glass.

Some of the pufferfish toxin is degraded in alkaline conditions. If it is left for a longer period of time, the ingredients may not even be detectable.

Xu Yiqing sighed: "Pufferfish poison has no taste, but aconitine has a pungent smell. And this pungent smell is diluted by the aroma of alcohol and almonds. I guess when Song Lang drinks it, he will just think that the wine he mixes is stronger than usual."

If Song Lang had noticed that the taste was not right and had been sent to the hospital for treatment immediately, his life might have been saved because of the two-hour buffer period left by the offset of the two toxins.

Unfortunately, this young man who was addicted to alcohol was eventually killed by his own wine glass and self-confidence.

Xu Yiqing closed the file and looked at everyone.

"Now we can determine the time when Song Lang was poisoned. The only question left is why my cup was also poisoned, but I didn't die?"

Zhou Shi said, "I have just discussed this with Boss Du, and we both agree that the poison is neither in the wine nor in the cup."

Xu Yiqing was puzzled: "Where else can it be?"

Zhou Shi said: "In the ice."

Xu Yiqing was stunned when he heard this, and then he suddenly realized: "I didn't die because I drank too quickly. I finished the wine before the ice melted?"

Zhou Shi nodded: "Song Lang drank for too long, the ice cubes melted, and the poison has entered the wine."

Du Yu quickly called the police: "Send all the ice in the nightclub for inspection. Be careful not to touch the ice, it's poisonous!"

After hanging up the phone, he was afraid: "Lao Xu, this beast really wants to kill you. If you drink too much, then..."

Unexpectedly, Xu Yiqing stroked the stubble on his chin and thought for a while.

"Old Du, I have a different opinion. From my past encounters with her, the [Cleaner] is a person who pays great attention to details. She must have known all of us. Someone who knows me well should know that I usually don't drink, and even if I do, I only drink a little."

This is no longer a secret. Not only do Zhou Shi, Du Yu, and Lin Sheng, who are close to him, know about it, but some distant colleagues also know that Xu Yiqing doesn't smoke and doesn't drink much.

On the day of the Winter Solstice Party, he only drank a little beer.

"Lao Xu, what do you mean?"

"Is it possible that she knew I could finish the drink before the ice started to melt?"

"You mean she didn't mean to kill you at all."

Xu Yiqing said: "Except for putting poison in the ice, I can't think of any way to poison Song Lang without poisoning me... After all, if she really wants to kill me, wouldn't it be more convenient to poison the wine directly?"

At least he didn't believe that someone could touch the ice in the nightclub's kitchen but not tamper with the opened wine.

Obviously this is safer. Once you drink it, you will die. No matter how many people drink it, they will die.

The cocktail Song Lang drank was one he mixed himself, which could not be sealed like retail bottles, so it was easy to poison the wine.

After expressing his guess, Xu Yiqing also felt very strange.

[Cleaner] He clearly called to threaten my life, so why did he deliberately avoid me when poisoning me, as if he was afraid that he would be implicated when he killed Song Lang?
(End of this chapter)