A button battery, which can be a very similar size to a coin, generates hydroxide ions at the anode and causes a chemical burn in two hours. An ingested button battery that is stuck in the esophagus is a medical emergency. In 2009, Avolio Luigi and Martucciello Giuseppe showed that although ingested nonmagnetic foreign bodies are likely to be passed spontaneously without consequence, ingested magnets (magnetic toys) may attract each other through childrens intestinal walls and cause severe damage, such as pressure necrosis, perforation, intestinal fistulas, volvulus, and obstruction. Pancreas
Sometimes foreign bodies can pass spontaneously through the gastrointestinal tract and perforate or penetrate the wall of stomach and duodenum and migrate into pancreas. The laparoscopic approach before open surgery could be performed safely for the removal of foreign bodies embedded in the pancreas. Airways
It is possible for a foreign body to enter the airways and cause choking. A choking case can require the fast usage of basic anti-choking techniques to clear the airway. In one study, peanuts were the most common obstruction. In addition to peanuts, hot dogs, grapes, and latex balloons are also serious choking hazards in children that can result in death. A latex balloon will conform to the shape of the trachea, blocking the airway and making it difficult to expel with basic anti-choking techniques. Eyes
Airborne particles can lodge in the eyes of people at any age. These foreign bodies often result in allergies which are either temporary or even turn into a chronic allergy.
This is especially evident in the case of dust particles. It is also possible for larger objects to lodge in the eye. The most common cause of intraocular foreign bodies is hammering. Corneal foreign bodies are often encountered due to occupational exposure and can be prevented by instituting safety eye-wear at work place.Foreign bodies in the eye affect about 2 per 1,000 people per year. Skin
Splinters are common foreign bodies in skin. Staphylococcus aureus infection often causes boils to form around them.Tetanus prophylaxis may be appropriate. Peritoneum
Foreign bodies in the peritoneum can include retained surgical instruments after abdominal surgery. Rarely, an intrauterine device can perforate the uterine wall and enter the peritoneum. Foreign bodies in the peritoneum eventually become contained in a foreign body granuloma. In the extremely rare case of retained ectopic pregnancy, this forms a lithopedion. Other
Foreign bodies can also become lodged in other locations:

anus or rectum
blood vessels or thoracic system
ears
nose
teeth and periodontium
urethra
vagina

Other animals
Foreign bodies are common in animals, especially young dogs and cats. Dogs will readily eat toys, bones, and any object that either has food on it or retains the odor of food. Unlike humans, dogs are susceptible to gastrointestinal obstruction due to their ability to swallow relatively large objects and pass them through the esophagus. Foreign bodies most commonly become lodged in the stomach because of the inability to pass through the pyloric sphincter into the jejunum. Symptoms of gastrointestinal obstruction include vomiting, abdominal pain often characterized by aggression, acute infection, and depression due to dehydration.