question: How the poison in/on an animal doesn't harm the animal itself?
comment: It's not usually located in a place that can be damaged by the poison. Humans are the same way, we have germs and other things in our digestive system that if they made it back up to our stomachs, we would be seriously ill. But our bodies are designed to keep things separated. & #x200B; That's why getting stabbed or shot can be extra dangerous if certain organs are punctured....things start to spill into places they really shouldn't be.
passages: Industry, agriculture, and other sectors employ poisonous substances for reasons other than their toxicity. Most poisonous industrial compounds have associated material safety data sheets and are classed as hazardous substances. Hazardous substances are subject to extensive regulation on production, procurement and use in overlapping domains of occupational safety and health, public health, drinking water quality standards, air pollution and environmental protection. Due to the mechanics of molecular diffusion, many poisonous compounds rapidly diffuse into biological tissues, air, water, or soil on a molecular scale. By the principle of entropy, chemical contamination is typically costly or infeasible to reverse, unless specific chelating agents or micro-filtration processes are available. Chelating agents are often broader in scope than the acute target, and therefore their ingestion necessitates careful medical or veterinarian supervision. 
   A poison which enters the food chain—whether of industrial, agricultural, or natural origin—might not be immediately toxic to the first organism that ingests the toxin, but can become further concentrated in predatory organisms further up the food chain, particularly carnivores and omnivores, especially concerning fat soluble poisons which tend to become stored in biological tissue rather than excreted in urine or other water-based effluents. 
   All living things produce substances to protect them from getting eaten, so the term "poison" is usually only used for substances which are poisonous to humans, while substances that mainly are poisonous to a common pathogen to the organism and humans are considered antibiotics. Bacteria are for example a common adversary for Penicillium chrysogenum mold and humans, and since the mold's poison only targets bacteria humans may use it for getting rid of bacteria in their bodies. Human antimicrobial peptides which are toxic to viruses, fungi, bacteria and cancerous cells are considered a part of the immune system.
   Most biocides, including pesticides, are created to act as poisons to target organisms, although acute or less observable chronic poisoning can also occur in non-target organisms (secondary poisoning), including the humans who apply the biocides and other beneficial organisms. For example, the herbicide 2,4-D imitates the action of a plant hormone, which makes its lethal toxicity specific to plants. Indeed, 2,4-D is not a poison, but classified as "harmful" (EU).
   Most biocides, including pesticides, are created to act as acute poisons to target organisms, although acute or less observable chronic poisoning can also occur in non-target organisms (secondary poisoning), including the humans who apply the biocides and other beneficial organisms. For example, the herbicide 2,4-D imitates the action of a plant hormone, which makes its lethal toxicity specific to plants. Indeed, 2,4-D is not a poison, but classified as "harmful" (EU).
   Biocides need not be poisonous to humans, because they can target metabolic pathways absent in humans, leaving only incidental toxicity. For instance, the herbicide 2,4-dichlorophenoxyacetic acid is a mimic of a plant growth hormone, which causes uncontrollable growth leading to the death of the plant. Humans and animals, lacking this hormone and its receptor, are unaffected by this, and need to ingest relatively large doses before any toxicity appears. Human toxicity is, however, hard to avoid with pesticides targeting mammals, such as rodenticides.
   BULLET::::- Predator-prey relationships – either the predator is affected by the toxin resulting in a decline of predator population and thus increasing the prey population; or the prey population is affected by the toxin resulting in a decline in the prey population that, in essence, will cause a decline in the predator population due to lack of food resources
   BULLET::::- We are all connected between the communities of living things. Plants can absorb toxins through their roots and leaves. Animals and humans are always exposed to chemicals by the air we breathe, things we touch, and what we put in our mouth.
  
  BULLET::::- Animals and humans can also eat other animals or plants that are already poisoned, which will continue the spread of chemicals, which is referred to as secondary poisoning
  
  Section::::Effects on individuals and entire population.
   Apart from food, many poisons readily enter the body through the skin and lungs. Hydrofluoric acid is a notorious contact poison, in addition to its corrosive damage. Naturally occurring sour gas is a notorious, fast-acting atmospheric poison (as released by volcanic activity or drilling rigs). Plant-based contact irritants, such as that possessed by poison ivy or poison oak, are often classed as allergens rather than poisons; the effect of an allergen being not a poison as such, but to turn the body's natural defenses against itself. Poison can also enter the body through faulty medical implants, or by injection (which is the basis of lethal injection in the context of capital punishment). 
   Secondary poisoning
  
  Secondary poisoning, or relay toxicity, is the poisoning that results when one organism comes into contact with or ingests another organism that has poison in its system. It typically occurs when a predator eats an animal, such as a mouse, rat, or insect, that has previously been poisoned by a commercial pesticide. If the level of toxicity in the prey animal is sufficiently high, it will harm the predator.
   The toxicology of MLA has been studied largely in the context of livestock poisoning by wild larkspurs. The seminal work by John Jacyno and Mike Benn at the University of Calgary in Canada showed that MLA was most likely to be the agent responsible for the toxicity of a local larkspur, "D. brownii", and provided some preliminary acute toxicity data in several animal species. These LDs are as follows: mouse, 3–5 mg/kg; frog, 3–4 mg/kg; rabbit, 2–3 mg/kg (after [[parenteral]] administration). Cats appeared to have comparable susceptibility to rabbits, whereas dogs were ~ 1.5 x more sensitive. These early observations have been comprehensively extended by USDA researchers, who have estimated the LD of MLA to be ~10 mg/kg in sheep, ~ 5 mg/kg in rats, and ~2 mg/kg in cattle.
   Mammals susceptible to secondary poisoning include humans, with infants and small children being the most susceptible. Pets such as cats and dogs, as well as wild birds, also face significant risk of secondary poisoning.
  
  Section::::Pesticides.
  
  Various pesticides such as rodenticides may cause secondary poisoning. Some pesticides require multiple feedings spanning several days; this increases the time a target organism continues to move after ingestion, raising the risk of secondary poisoning of a predator.
   Short-term inhalation of HCCPD is  lethal to mice, rats, rabbits and guinea pigs. The lethality of the animals can be affected by the concentration and duration of HCCPD exposure. From all the animals tested, guinea pigs showed to be the most resistant to the compound toxicity. Almost all biological systems are shown to be vulnerable to the toxicity of HCCPD, except the hematological and musculoskeletal systems.
  
  Section::::Effects on animals.:Oral effects.
   The best-known active ingredients of "Tylecodon" species are Bufadienolides biochemically related to toad venoms and bile acids. In some species more than half a dozen such compounds have been identified. As such they are nervous and muscle poisons that cause various cardiac symptoms. In livestock they cause various forms of the condition known as "krimpsiekte", meaning "contraction" or "shrinking" disease. The meat of poisoned animals is dangerous to dogs or humans that eat it. However, it also is claimed that the meat is only dangerous to eat if it is raw or incompletely cooked, and that it may be eaten with relative safety if thoroughly cooked. If this is correct, it is not clear why cooking should have such an effect, and accordingly readers should be cautious in relying on such claims.
   BULLET::::- Mouse and rat poison is commonly found in the house or garage. Dogs readily eat these poisons, which look like small green blocks and are very attractive to them. The poisons work by depleting stores of Vitamin K in the body, without it, blood cannot clot properly. Clinical signs of poisoning include depression, weakness, difficulty breathing, bruising, and bleeding from any part of the body. These clinical signs often take 3 to 4 days to show up. A blood test will show that the blood is not clotting properly. If the poison has only recently been ingested (within 2 to 3 hours), the dog should be given apomorphine or hydrogen peroxide to make it vomit. Activated charcoal can be given to absorb any remaining poison in the gastrointestinal tract. Then the dog is given Vitamin K supplementation for 3 to 4 weeks, depending on the type of poison. At the end of treatment, the clotting times should be tested again. The prognosis is good in these cases. However, if the dog is already showing signs of poisoning, it is too late to try to remove the poison from the body. A whole blood transfusion or plasma is given to treat the anemia and to try to control bleeding. Vitamin K is also given. The prognosis is poor in these cases.
   The risk from toxicity is also distinct from toxicity itself. For instance, the preservative thiomersal used in vaccines is toxic, but the quantity administered in a single shot is negligible.
  
  Section::::History.
   There can be wide variability between species as well; what is relatively safe for rats may very well be extremely toxic for humans ("cf." paracetamol toxicity), and vice versa. For example, chocolate, comparatively harmless to humans, is known to be toxic to many animals. When used to test venom from venomous creatures, such as snakes, LD results may be misleading due to the physiological differences between mice, rats, and humans. Many venomous snakes are specialized predators of mice, and their venom may be adapted specifically to incapacitate mice; and mongooses may be exceptionally resistant. While most mammals have a very similar physiology, LD results may or may not have equal bearing upon every mammal species, including humans.
   Recent studies present NRB's ability to activate the mitochondrial permeability transition pore (MPTP) in isolated rat preparations. Cell apoptosis and necrosis are (amongst other things) regulated by MPT pores. It is understandable that such an abnormity in the mitochondrial membranes bring about issues in the cellular metabolism of the poisoned animal.
  
  Section::::Toxicity.:Toxicity studies in mammals and birds.
   Four potential processes exist for a chemical interacting with an animal: absorption, distribution, metabolism and excretion (ADME). Absorption describes the entrance of the chemical into the body, and can occur through the air, water, food, or soil. Once a chemical is inside a body, it can be distributed to other areas of the body through diffusion or other biological processes. At this point, the chemical may undergo metabolism and be biotransformed into other chemicals (metabolites). These metabolites can be less or more toxic than the parent compound. After this potential biotransformation occurs, the metabolites may leave the body, be transformed into other compounds, or continue to be stored in the body compartments.
   Two common cases of acute natural poisoning are theobromine poisoning of dogs and cats, and mushroom poisoning in humans. Dogs and cats are not natural herbivores, but a chemical defense developed by "Theobroma cacao" can be incidentally fatal nevertheless. Many omnivores, including humans, readily consume edible fungi, and thus many fungi have evolved to become decisively inedible, in this case as a direct defense.
  
  Section::::Poisoning.:Chronic.
   Many substances regarded as poisons are toxic only indirectly, by toxication. An example is "wood alcohol" or methanol, which is not poisonous itself, but is chemically converted to toxic formaldehyde and formic acid in the liver. Many drug molecules are made toxic in the liver, and the genetic variability of certain liver enzymes makes the toxicity of many compounds differ between individuals.
  
  Exposure to radioactive substances can produce radiation poisoning, an unrelated phenomenon.
   Section::::Examples.:In "Bordetella pertussis".
   Research studies on ewes has shown that skeletal and cardiac myodegeneration (damage of muscle tissues) only occur after a dose sufficient to induce symptoms of intoxication is administered. Analysis of the animal's blood showed elevated serum enzymes that indicate muscle damage (LDH, AST and CK values). At necropsy, the ewe's heart had multifocal pale areas and pallor of the long digital extensor muscle groups; by contrast, a ewe given a lethal dose of cicutoxin-containing tubers had only microscopic lesions. The number and duration of seizures had a direct effect on the skeletal and cardiac myodegeneration and amount of serum change.
   In comparison to IV injection, the toxicity of palytoxin in various animals via intramuscular and subcutaneous injections are 2.5 and 4–30 times higher, respectively. Upon ingestion the toxicity in animals has been 200 times less than via IV. In the table below, there are listed some LD values for partially pure palytoxin obtained from different "Palythoa". These values represent the amount of palytoxin required to kill half of the test animals. Values are in micrograms (µg) per kilogram of the animal's weight and have been measured 24 hours after the initial exposure.
   BULLET::::- Injected poisons (e.g., from the sting of animals) can be treated by binding the affected body part with a pressure bandage and placing the affected body part in hot water (with a temperature of 50 °C). The pressure bandage prevents the poison being pumped throughout the body, and the hot water breaks it down. This treatment, however, only works with poisons composed of protein-molecules.
  
  BULLET::::- In the majority of poisonings the mainstay of management is providing supportive care for the patient, i.e., treating the symptoms rather than the poison.
  
  Section::::Management.:Decontamination.
  