| Oral toxicity (mg/kg) | ||
|---|---|---|
| TDLo | LD50 | |
| Cat | 200 | |
| Dog | 16 | 300 |
| Human | 26 | ~1,000 |
| Mouse | 837 | |
| Rabbit | 1,000 | |
| Rat | 1,265 |
Theobromine poisoning, also informally called chocolate poisoning or cocoa poisoning, is an overdosage reaction to the xanthine alkaloid theobromine, found in chocolate, tea, cola beverages, [1] and some other foods.
Cocoa powder contains about 2.1% theobromine by weight, [2] so 14 g (0.5 oz ) of raw cocoa contains approximately 0.3 g theobromine.
Processed chocolate, in general, has smaller amounts. The amount found in highly refined chocolate candies or sweets (typically 1.4–2.1 g/kg or 40–60 mg/oz) is much lower than that of dark chocolate or unsweetened baking chocolate (>14 g/kg or >400 mg/oz ).
Theobromine has a half-life of 10 hours , but over 16% may be unmodified 48 h after a single dose of 10 mg/kg (0.00016 oz/lb) [3]
In general, the amount of theobromine found in chocolate is small enough that chocolate can be safely consumed by humans with a negligible risk of poisoning. [4]
Theobromine doses at 0.8–1.5 g per day, such as may be found in 50–100 g (1.8–3.5 oz) of cocoa powder, may be accompanied by sweating, trembling and severe headaches. These are the mild-to-moderate symptoms.[ citation needed ]
The severe symptoms are cardiac arrhythmias, [5] epileptic seizures, internal bleeding, heart attacks, and eventually death.[ citation needed ]
Limited mood effects were shown at 250 mg per day.[ citation needed ]
Median lethal (LD50) doses of theobromine have only been published for cats, dogs, rats, and mice; these differ by a factor of 6 across species. [6]
Serious poisoning happens more frequently in domestic animals, which metabolize theobromine much more slowly than humans, [7] and can easily consume enough chocolate to cause poisoning. The most common victims of theobromine poisoning are dogs, [8] [9] for whom it can be fatal. The toxic dose for cats is even lower than for dogs. [10] However, cats are less prone to eating chocolate since they are unable to taste sweetness. [11] Theobromine is less toxic to rats and mice, who all have an LD50 of about 1,000 mg/kg (0.016 oz/lb).
In dogs, the biological half-life of theobromine is 17.5 hours; in severe cases, clinical symptoms of theobromine poisoning can persist for 72 hours. [12] Medical treatment performed by a veterinarian involves inducing vomiting within two hours of ingestion and administration of benzodiazepines or barbiturates for seizures, antiarrhythmics for heart arrhythmias, and fluid diuresis. Theobromine is also suspected to induce right atrial cardiomyopathy after long term exposure at levels equivalent to approximately 15 g/kg (0.24 oz/lb) of dark chocolate per day. [13] According to the Merck Veterinary Manual, baker's chocolate of approximately 1.3 g/kg (0.021 oz/lb) of a dog's body weight is sufficient to cause symptoms of toxicity. [14] For example, 0.4 oz (11 g) of baker's chocolate would be enough to produce mild symptoms in a 20 lb (9.1 kg) dog, while a 25% cacao chocolate bar (like milk chocolate) would be only 25% as toxic as the same dose of baker's chocolate. [15] One ounce of milk chocolate per pound of body weight (63 g/kg) is a potentially lethal dose in dogs. [14]
In 2014, four American black bears were found dead at a bait site in New Hampshire. A necropsy and toxicology report performed at the University of New Hampshire in 2015 confirmed they died of heart failure caused by theobromine after they consumed 41 kg (90 lb) of chocolate and doughnuts placed at the site as bait. A similar incident killed a black bear cub in Michigan in 2011. [16]
In previous research, the USDA investigated the possible use of theobromine as a toxicant to control coyotes preying on livestock. [17]
Chocolate is a food made from roasted and ground cocoa beans that can be a liquid, solid, or paste, either on its own or as a flavoring in other foods. The cacao tree has been used as a source of food for at least 5,300 years, starting with the Mayo-Chinchipe culture in what is present-day Ecuador. Later, Mesoamerican civilizations consumed cacao beverages, of which one, chocolate, was introduced to Europe in the 16th century.
Theobromine, also known as xantheose, is the principal alkaloid of Theobroma cacao. Theobromine is slightly water-soluble (330 mg/L) with a bitter taste. In industry, theobromine is used as an additive and precursor to some cosmetics. It is found in chocolate, as well as in a number of other foods, including tea, some American hollies and the kola nut. It is a white or colourless solid, but commercial samples can appear yellowish.
Chlorfenvinphos is an organophosphorus compound that was widely used as an insecticide and an acaricide. The molecule itself can be described as an enol ester derived from dichloroacetophenone and diethylphosphonic acid. Chlorfenvinphos has been included in many products since its first use in 1963. However, because of its toxic effect as a cholinesterase inhibitor it has been banned in several countries, including the United States and the European Union. Its use in the United States was discontinued in 1991.
Rodenticides are chemicals made and sold for the purpose of killing rodents. While commonly referred to as "rat poison", rodenticides are also used to kill mice, woodchucks, chipmunks, porcupines, nutria, beavers, and voles. Despite the crucial roles that rodents play in nature, there are times when they need to be controlled.
Solanine is a glycoalkaloid poison found in species of the nightshade family within the genus Solanum, such as the potato. It can occur naturally in any part of the plant, including the leaves, fruit, and tubers. Solanine has pesticidal properties, and it is one of the plant's natural defenses. Solanine was first isolated in 1820 from the berries of the European black nightshade, after which it was named. It belongs to the chemical family of saponins
Abrin is an extremely toxic toxalbumin found in the seeds of the rosary pea, Abrus precatorius. It has a median lethal dose of 0.7 micrograms per kilogram of body mass when given to mice intravenously. The median toxic dose for humans ranges from 10 to 1000 micrograms per kilogram when ingested and is 3.3 micrograms per kilogram when inhaled.
Taxus cuspidata, the Japanese yew or spreading yew, is a member of the genus Taxus, native to Japan, Korea, northeast China and the extreme southeast of Russia.
The health of dogs is a well studied area in veterinary medicine.
Paraxanthine, also known as 1,7-dimethylxanthine, is a metabolite of theophylline and theobromine, two well-known stimulants found in coffee, tea, and chocolate mainly in the form of caffeine. It is a member of the xanthine family of alkaloids, which includes theophylline, theobromine and caffeine.
Persin is a fungicidal toxin present in the avocado. Persin is an oil-soluble compound structurally similar to a fatty acid, a colourless oil, and it leaches into the body of the fruit from the seeds.
The consumption of grapes and raisins presents a potential health threat to dogs. Their toxicity to dogs can cause the animal to develop acute kidney injury with anuria. The phenomenon was first identified by the Animal Poison Control Center (APCC), run by the American Society for the Prevention of Cruelty to Animals (ASPCA). Approximately 140 cases were seen by the APCC in the one year from April 2003 to April 2004, with 50 developing symptoms and seven dying.
Strychnine poisoning is poisoning induced by strychnine. It can be fatal to humans and other animals and can occur by inhalation, swallowing or absorption through eyes or mouth. It produces some of the most dramatic and painful symptoms of any known toxic reaction, making it quite noticeable and a common choice for assassinations and poison attacks. For this reason, strychnine poisoning is often portrayed in literature and film, such as the murder mysteries written by Agatha Christie.
The health of domestic cats is a well studied area in veterinary medicine.
Ethylene glycol poisoning is poisoning caused by drinking ethylene glycol. Early symptoms include intoxication, vomiting and abdominal pain. Later symptoms may include a decreased level of consciousness, headache, and seizures. Long term outcomes may include kidney failure and brain damage. Toxicity and death may occur after drinking even in a small amount as ethylene glycol is more toxic than other diols.
Paracetamol poisoning, also known as acetaminophen poisoning, is caused by excessive use of the medication paracetamol (acetaminophen). Most people have few or non-specific symptoms in the first 24 hours following overdose. These symptoms include feeling tired, abdominal pain, or nausea. This is typically followed by absence of symptoms for a couple of days, after which yellowish skin, blood clotting problems, and confusion occurs as a result of liver failure. Additional complications may include kidney failure, pancreatitis, low blood sugar, and lactic acidosis. If death does not occur, people tend to recover fully over a couple of weeks. Without treatment, death from toxicity occurs 4 to 18 days later.
α-Naphthylthiourea (ANTU) is an organosulfur compound with the formula C10H7NHC(S)NH2. This a white, crystalline powder although commercial samples may be off-white. It is used as a rodenticide and as such is fairly toxic. Naphthylthiourea is available as 10% active baits in suitable protein- or carbohydrate-rich materials and as a 20% tracking powder.
Antiarins are cardiac glycoside poisons produced by the upas tree. There are two closely related forms, α-antiarin and β-antiarin. The two share the same aglycone, antiarigenin, but differ in the sugar group that is attached to it.
Taxine alkaloids, which are often named under the collective title of taxines, are the toxic chemicals that can be isolated from the yew tree. The amount of taxine alkaloids depends on the species of yew, with Taxus baccata and Taxus cuspidata containing the most. The major taxine alkaloids are taxine A and taxine B although there are at least 10 different alkaloids. Until 1956, it was believed that all the taxine alkaloids were one single compound named taxine.
Methyl fluoroacetate (MFA) is an organic compound with the chemical formula FCH2CO2CH3. It is the extremely toxic methyl ester of fluoroacetic acid. It is a colorless, odorless liquid at room temperature. It is used as a laboratory chemical and as a rodenticide. Because of its extreme toxicity, MFA was studied for potential use as a chemical weapon.
Food products and household items commonly handled by humans can be toxic to dogs. The symptoms can range from simple irritation to digestion issues, behavioral changes, and even death. The categories of common items ingested by dogs include food products, human medication, household detergents, indoor and outdoor toxic plants, and rat poison.