There are many causes of food poisoning:
· Bacteria are responsible for the highest number of outbreaks. 80% of all food poisoning cases are caused by bacteria.
· Chemicals such as cleaning products, excess additives and preservatives, fuel fumes, strong after shaves/perfumes, agricultural chemicals, pesticides. In 1997 aluminum sulphate was inadvertently dumped into a reservoir in Camelford, Cornwall, UK. Twelve years later many relations of people who have died from Alzheimer's disease, claim that the contamination in 1997 caused their deaths. (Autopsies of Alzheimer victims show a large proportion of aluminum in their brain cells compared to people who have not suffered from dementia).
In the 1970s an Austrian wine company deliberately sweetened their produce with industrial anti-freeze.
In the 1980s a Spanish company passed off used, industrial motor oil as virgin olive oil.
In 2008 a Chinese company deliberately added melamine to baby milk powder.
In the above examples there were a considerable number of deaths.
· When certain moulds grow on fruit or grains, they produce a poison called a mycotoxin, such as ochratoxin A and patulin. Both can cause cancer.
· Metals such as cadmium, zinc, lead and mercury can cause illness. Also one has to be careful what type of metallic container acidic fruit is cooked in. In the catering industry we tend mainly to use aluminum saucepans. If acidic fruit is cooked in aluminum, the metal becomes discoloured and the fruit retains a metallic taint. Probably not life threatening in the short term, but certainly illegal as far as the UK legislation is concerned. The best container to use would be one that would not react with the fruit such as stainless steel or glass.
· Only food safe plastics must be used for storage of food items. Plastic containers bought from hardware stores that are not meant for food storage contain industrial dyes, which can contain arsenic and strychnine, which could leach into the food.
· Natural poisons include poisonous fungi, rhubarb leaves, deadly nightshade and dried red kidney beans. Always ensure you identify the edible species of fungi if you like foraging for wild mushrooms. Rhubarb leaves contain oxalic acid (wood bleach), which is deadly poisonous. Deadly nightshade was found in dried fruit tea, imported from Germany, several years ago, which caused severe illness. Dried red kidney beans contain a natural toxin. In order to deactivate the poison, the beans must be boiled vigorously for at least 15 minutes before using. The boiling can be before or after soaking. Canned red kidney beans are safe; they have already been processed to de-activate the toxin.
· Fresh fish must be thoroughly cooked before eating. Do not undercook as serious parasitic infection could ensue. The freshest fish to eat is frozen fish, strangely enough! All fish, whether from fresh or sea water, from cold or warm temperatures contain parasites within the flesh. Cooking the fish to the right temperature will kill all parasites and the fish will be safe to eat. If the fish is undercooked, as some "so called" telly chefs would insist, then you can develop a parasitic infection, which can be quite serious. If fish is to be undercooked, then it must be frozen first, which will kill the parasites. Under UK health and safety legislation, all fish used for use with Sushi rice, must be frozen for at least 36 hours before being used. All animals, including fish, must be refrigerated immediately after slaughter, to prevent any build up of bacterial growth and toxin production. Depending on the fishmonger's or supermarket's location, it can take as long as 7 days for the fresh fish to be transported from water to display. If the integrity of the cold chain has been compromised in any way, the fish can be hazardous.
Fugu (Puffer or Blow fish) is a delicacy in Japanese restaurants. The internal organs: the ovaries, liver and skin, contain a deadly toxin (tetrodotoxin). If the fish is not prepared correctly, the toxin can leach into the flesh and cause lethal poisoning if ingested. The poison causes paralysis of the muscles while the victim stays fully conscious, and eventually dies from asphyxiation. There is no available antidote. In order to prepare fugu, the chef must be licensed. The training course for licensing lasts for two years. Part of the training course involves eating their preparation. 75% of trainee chefs fall seriously ill, some die, during the training course. If you see this delicacy on a menu, give it a wide berth, unless you are one to live on the edge!
Some symptoms of food poisoning include:
Nausea
Vomiting
Abdominal Cramps
Diarrhoea
These are the body's self defence mechanisms to deal with the disease. When pathogens are ingested with food, the chemicals on the bacterial membrane act as an alert signal, which the brain quickly senses and sends messages, firstly to the oesophagus, giving rise to nausea, and secondly to the stomach. The vomiting centre (a region within the brain) instructs the stomach to expel all contents as quickly as possible (vomiting).
Another line of defence is the stomach. The parietal cells within the epithelium of the stomach secrete hydrochloric acid (gastric juices). Its main purpose is to start to break down food and kill pathogens. The acid is non discriminatory and will kill all bacteria, including the pre-biotic bacteria that allegedly help the digestive processes. The main digestive processes take place in the small intestine, which the pre-biotics never reach! Because of the size of that industry, no government of the day will repudiate their claims.
E coli are acid tolerant bacteria and if they remain in the stomach after vomiting, they resist the stomach acid and reach the small intestine. The bacteria will start to grow and attract the body's next line of defence, its antibodies. The antibodies attack the bacteria and a battle commences. This battle causes the stomach cramps. Some variants of E coli release poisons into the blood stream, which affect the kidneys, often causing kidney failure.
If other bacteria manage to invade the small intestine, they also cause stomach cramps.
We have symbiotic bacteria living in our colon, which break down the last of the food material, leaving faeces. Even E coli are residents, but harmless, helpful variants; good friends! These E coli synthesise vitamin K from the food, which acts as a blood clotting factor. So if it wasn't for E coli we could bleed to death!
However, as the surviving pathogens enter the colon they interrupt the colon's main duty of absorbing as much water as possible from the faeces and actually reverses the process. The bacteria cause an influx of chloride ions into body cells, causing a mass diffusion of water from the cells to enter the colon, mixing with the faeces and giving rise to diarrhoea.
The symptoms of food poisoning are not life threatening, albeit not very pleasant. The life threatening element of food poisoning is dehydration, resulting from fluid loss via vomiting and diarrhoea. Dehydration does kill.
The body requires sufficient water and salts in order for the major organs to work. Severe dehydration causes the organs to fail, resulting in death.
Dehydration is not a serious problem in developed countries as fluids can be replaced with chlorinated tap water or bottled water. In under-developed countries which have a non-chlorinated water supply or well water, hydration can exacerbate the situation. The water might well be contaminated from faeces or decomposing animal life.
Natural disasters are also a major problem, such as earthquakes and floods. Even "clean" drinking water becomes contaminated from dead and dying animals and faeces from flooded or damaged sewers.
Statistically speaking, if no clean water is available for disaster victims, at least 50 times the number of people who are killed by the disaster, will be affected, and possibly die, from food poisoning or from a Foodborne disease such as typhoid or cholera.
There are groups of people who are more affected by food poisoning than healthy adults.
They are:
· The elderly, whose immune system is not as strong as it used to be, their organs are much weaker as they get older. In 1996, 22 people died from E coli food poisoning in Wishaw, in Scotland. All victims were elderly.
· The very young haven't developed an immune system yet, their organs are still not fully developed to be able to cope with poisoning. Mason Jones, a five year old child from Deri, South Wales, died from E coli food poisoning due to contaminated meat supplied by a butcher in Bridgend, South Wales.
· People who are already ill cannot fight another disease. The body has evolved to competently fight one disease at a time. It concentrates all its resources to one battle only.
· Pregnant women can become infected by Listeria, bacteria that infect the placenta, and prevent nutrients and oxygen from reaching the foetus, causing stillbirth or miscarriage.
The majority of food poisoning is caused by bacteria. Other culprits of food poisoning include chemicals, moulds, metals, plastics, natural poisons, and fresh fish. The symptoms of food poisoning are the body's self defence mechanisms. The groups of people who are more susceptible to food poisoning than health adults include the elderly, very young, pregnant women and ill or immunocompromised.