Non Bacterial Food Posioning
Food poisoning can be caused by the consumption of food contaminated by substances other than bacteria. This can occur by contamination of the food by chemicals, the ingestion of poisonous plants and by eating fish or shellfish that have been feeding on poisonous plankton or living in contaminated waters. Several foods contain naturally occurring poisons. This is more common in plants; there are hardly any animals that are naturally toxic to humans. Examples of these are Chilli peppers contain capasaicin, garlic and onions contain sulphur. Uncooked red kidney beans, some toadstools, daffodil bulbs, puffer fish and green potatoes are all poisonous to humans.
(a)When considering chemical poisoning it is important to take into account poisonings caused by ingestion of metallic elements. Metallic poisoning usually involve the heavy metals those with a pH greater than 5. Heavy metal poisoning can be acute or chronic it can be caused by lead, mercury, iron, thallium, Bismuth, cadmium, copper, tin, zinc. Heavy metal contamination can occur when plants are grown or animals grazed on land which is already contaminated are eaten by humans. It also occurs when food is stored in faulty or damaged containers made of tin, lead copper and zinc. Contamination may occur from leaching utensils, contaminated water and solder residues in cans. When they are consumed they are then stored in the soft tissues of the body. The heavy metals once absorbed compete with other ions and bind to proteins causing impaired enzymatic activity resulting in damage to many organs throughout the body. The most common heavy metal poisoning is lead. This has been falling in the western world with the removal of lead pipes, and lead from pipes, paint and food cans. It is important to only use food approved packaging and containers as chemicals such as benzene can leak out of the packaging and contaminate the food. You