Those who have been scalded by hot water will show separation and shedding of skin and flesh, with the skin appearing white. Areas adhering to the flesh are also white, while areas with more muscle tissue may rot and appear reddish.

If death occurs in boiling water or fire, the body is often found lying prone, with injuries primarily on the hands, feet, head, face, and chest. If caused by a struggle, or if the head was bumped, foot stepped on, or hand pushed into the hot liquid/fire, injuries are more likely on the back, buttocks, and legs, possibly accompanied by contusions. The swelling is less pronounced compared to other types of scalding injuries.

In cases of fatal poisoning, the corpse's mouth and eyes are often open, with a purplish-dark or cyanotic complexion, purple-black lips, and cyanotic nails on hands and feet. Blood may exude from the mouth, eyes, ears, and nose. The tips of the nails turn black, and the throat and abdomen become distended and blackened, sometimes with blisters. The body may exhibit cyanotic patches, protruding eyeballs, and flow of dark purple-black blood from the mouth, nose, and eyes. Hair and beard may float and be difficult to wash. Prior to death, the victim may vomit foul matter or pass black blood. The anus may swell and protrude, or even the large intestine may prolapse.

There are exceptions: those who poison themselves on an empty stomach may present only with abdominal cyanosis and distension, without cyanosis of the lips or nails. Those who poison themselves after a full meal may show cyanosis of the lips and nails but not the abdomen. Additionally, elderly or chronically ill individuals with weak internal organs may die from small doses of poison without showing cyanosis in the abdomen, lips, or nails; these cases require comprehensive assessment based on other symptoms.

If poisoning occurred during life and the body turned cyanotic-black over several days, the skin and flesh remain intact but black. If time passes long enough for decomposition, revealing bones, the bones turn greyish-black.

If poison is placed in the mouth post-mortem to simulate poisoning, the skin, flesh, and bones will appear yellowish-white.

Poisoning can manifest immediately or within hours of ingestion. Slow-acting poisons may take one or two days to cause symptoms. Vomiting may be intermittent or continuous. Investigators should search clothing for residual poison and look for containers near where the deceased was sitting.

Insect venom poisoning presents as deep cyanotic-black discoloration all over the body, including the head, face, chest, and heart area, accompanied by abdominal distension, hematemesis (vomiting blood), or hematochezia (blood in stool).

Rat-bane grass poison (found in Jiangnan) resembles insect venom poisoning but includes cracked lips and cyanotic-black gums. Symptoms typically manifest in the nine orifices (eyes, ears, nose, mouth, urethra, anus) with bleeding after one night to one day.

Poisoning from fruits or mineral/stone medicines may cause localized redness and swelling resembling bruising, or large patches of cyanotic-black discoloration. Nails turn black, slight bleeding may occur in muscle crevices, and symptoms include abdominal distension or bloody diarrhea.

Alcohol toxicity causes abdominal distension, vomiting, or bloody diarrhea.

Arsenic or wild kava poisoning manifests after about two hours (one "fu" period) with small rashes turning cyanotic-black, protruding eyes, spiky and split tongue, ruptured lips, enlarged ears, abdominal distension, anal fissure, and blackening of all ten fingernails.

Golden silkworm gu poison results in a emaciated corpse with yellowish-white skin, sunken eyes, exposed teeth, retracted lips, and collapsed abdomen. Testing with a silver hairpin yields a yellowish color that cannot be removed by soap nut water.

An alternative description states that the body swells, skin blisters like scalds, eventually forming pus, with ruptured tongue, lips, and nose, characteristic of golden silkworm gu poison.

Cyanotic-black discoloration of nails and body, bleeding from mouth and nose, splitting skin, and exposure of tongue and anus indicate herbal or mushroom poisoning.

Emaciation due to vomiting and diarrhea, slightly blackened but unruptured skin, absence of oral blood, and no anal bleeding suggest incompatibility between consumed alcohol and food.

To test for poisoning, clean a silver hairpin with soap nut water, insert it into the deceased's throat, seal with paper, and leave for a while. If it turns cyanotic-black, poisoning is confirmed. Washing with soap nut water again; if the color persists, it confirms poisoning. If it remains bright white, there is no poisoning.

If ingested food has moved into the intestines and testing via the throat yields negative results, test via the anus instead.

For cases where long-term accumulation of poison makes detection difficult, first insert a silver or copper hairpin into the throat. Then, apply hot fermented rice vinegar from the bottom upwards, ensuring heat penetrates to vaporize the toxin. The black color will then appear. Pouring vinegar from top to bottom forces vapors downward, preventing visibility. When testing the anus, reverse the direction of application.

Another method involves steaming three sheng of rice or glutinous rice. Wash one sheng of pure glutinous rice, wrap in cloth, and steam atop the rice. Crack one egg (or duck egg), mix the white with the glutinous rice until uniform. Place this mixture on the steamed rice. Form the glutinous rice into a ball the size of a duck egg with three fingers, keeping it warm. Quickly open the corpse's mouth and place the rice ball outside the teeth. Cover the mouth, ears, nose, buttocks, and genitalia with 3-5 sheets of paper. Boil 3-5 strips of new cotton wadding in 3-5 sheng of strong vinegar over high heat for half an hour. Remove the wadding. Place the corpse on a bed of fermented rice dregs, cover with the boiled wadding. If poisoned during life, the body will swell, emit a foul odor from the mouth, and spray black, foul fluid onto the wadding. After removing the wadding, the glutinous rice will turn black and foul-smelling, confirming poisoning. If unchanged, poisoning is unlikely. Seal the tested rice and report findings clearly to the authorities. This method was verified by the Court of Judicature and Revision.

In Guangnan, disputes sometimes lead individuals to falsely accuse others by committing suicide with Hu Man Cao (Hemlock), also known as Chang Chang Cao (Intestine-Breaking Grass). It resembles Asafoetida, with long, pointed leaves growing on vines. Ingesting three or more leaves is fatal. Dried leaves stored for long periods, ground into powder, are also lethal. If ingested recently, flushing with fecal juice can antidote it. The plant's leaves move when approached. Soaking tender leaf hearts in water creates a solution where even a drop causes bleeding from all orifices. Antidote: Grind a broody hen that fails to hatch eggs, mix with sesame oil, and force-feed through the mouth. This induces vomiting of toxins and recovery. Delay renders it untreatable.