1, the food itself is harmful and toxic: such as poison ivy, mangosteen, sprouted potatoes, cassava, bitter almonds, puffer fish, Huangshui fish, poisonous mussels and so on.

2, food is harmful and toxic pollution, such as chemical poisons, harmful biological pollution.

3, unhygienic equipment, containers or utensils.

4, raw and cooked food cross-contamination.

5, the use of spoiled raw materials.

6, the remaining food is not reheated.

7, misuse of toxic and harmful substances.

8, improper storage.

9, improper food processing and cooking.

10, poor personal hygiene.

Second, the classification of food poisoning

1, microbial food poisoning

(1) bacterial food poisoning, characteristics: gastrointestinal symptoms, often accompanied by fever, the incubation period is relatively large compared to the chemical.

(2) mycotoxins and fungal food poisoning, characteristics: poisoning occurs mainly through the fungal contamination of food; with the general cooking method of heating treatment can not destroy the mycotoxins in the food; there is no contagious and immune, mycotoxins, generally small molecules of chemicals, the body does not produce antibodies; the fungal growth and reproduction and the production of toxins require a certain temperature and humidity, so the poisoning often There is a clearer seasonality and regionality.

2, chemical food poisoning, characteristics: the onset and eating time, the amount of food;; fast onset, short incubation period, mostly in a few minutes to a few hours; often group, patients have the same clinical manifestations; the degree of poisoning is serious, the duration of the disease is long, the morbidity and mortality rate is high; seasonal and regional are not obvious, poisoned food is not specific; the remaining food, vomit, blood and urine samples can be detected. The chemical poison can be detected in the samples of leftover food, vomit, blood and urine, etc.; accidental eating of chemical substances mixed with strong poison or eating food contaminated by poisonous chemicals; the clinical manifestations are diversified according to the toxic substances, and are usually not accompanied by fever.

Third, the prohibition of procurement of food

1, corruption and deterioration, oil rancidity, mold, insects, dirty, unclean, mixed with foreign bodies or other sensory abnormalities, containing toxic and harmful substances or contaminated with toxic and harmful substances, may be harmful to human health of the food;

2, without medical hygiene inspection or inspection failure of meat and its products;

3, more than the shelf life or does not meet the food labeling requirements of the fixed-package food;

4, other food hygiene standards and requirements do not meet the food.

Fourth, why the leftovers should be thoroughly heated before consumption

A variety of leftovers should be placed in the refrigerator as soon as possible, and then consumed should be thoroughly heated, which is the best way to eliminate microorganisms, leftovers in the storage of microorganisms may have been growth and reproduction, because suitable storage can only slow down the growth of microorganisms and can not kill them, so leftovers should be consumed as much as possible when the meal. Thorough heating means that the temperature of all parts of the food reaches at least 70°C or higher. Normally, this ensures the hygienic quality of food.

But fresh vegetables are best not eaten overnight or in alternate meals. A variety of leafy vegetables in particular, such as cabbage contains a large number of nitrates, leftover cabbage after a night, due to the role of bacteria, non-toxic nitrates will be converted to highly toxic nitrites. Nitrite can oxidize low iron hemoglobin into high iron hemoglobin in human blood, causing headache, dizziness, nausea, vomiting, panic and other symptoms of poisoning, nitrite is also a carcinogen.

Fifth, why some of the bad habits of the hand action is potentially dangerous

Our hands have a lot of small action is not consciously and often repeated. Such as wiping the nose, scratching the hair, scratching the beard, touching the mouth, scratching the itch, these actions, if connected with making drinking dishes, there is a risk of mutual contamination. Historically, there have been incidents of disease epidemics due to these actions. We should avoid these small actions when making food and wash our hands immediately if we notice any of these actions, don't be afraid of trouble. Collective canteens, hotels, restaurants and so on especially so, to develop good hygiene habits, is to prevent disease epidemics, to ensure that eat one of the important aspects of health.

Six, why you should avoid using your hands to direct contact with cooked food and other ready-to-eat food

There are a large number of bacteria on the hands, although in contact with the food before the wash, but it is not possible to wash away all. Most cooked and other ready-to-eat foods are no longer heated, and once contaminated, bacteria can enter the body with these foods and cause food poisoning.

If you have to use your hands to handle food, you should wear gloves (if the food is wrapped or needs to be cooked again, you don't need to wear gloves). Gloves should be worn with the following requirements:

1. When gloves are torn, contaminated or taken off for any reason, they should be discarded.

2. Change gloves between handling raw and cooked food.

3. Gloves should be changed frequently (at least every hour).

4. Gloves should not be reused after use.

7, why cooking method is not appropriate, can produce a variety of cancer-causing factors

In daily life, due to improper cooking methods, will produce a variety of cancer-causing factors.

1, animal meat, fish and other animal proteins, fire super, easy to produce carcinogens aminomethyl derivatives, so the animal poultry meat, fish and meat, can not be stir-fried, burnt after the more inappropriate to eat.

2, high-temperature heating or frying food, can produce carcinogenic PAHs, so you should eat less or not eat fried food.

3, fresh vegetables after washing and cutting shelved for too long will produce carcinogens nitrite, so vegetables should be washed, now cut, now fried, now eat, so as to avoid the production of nitrites, but also to reduce the loss of nutrients, especially water-soluble vitamin loss.

4, it is strictly prohibited to use coal, crude oil, firewood and other fuels to smoke food, otherwise it will produce carcinogens 3.4 benzopyrene, harmful to humans.

Eight, why there will be food poisoning

Food poisoning should be poisoned food, and the food with a sufficient dose of disease-causing factors, with these two, can cause food poisoning.

After analyzing, there are ten common factors that cause food poisoning:

1, inappropriate refrigeration of food (refrigeration temperature is not enough);

2, in the room temperature storage food (room temperature in the range of the dangerous temperature band);

3, premature preparation of food (so that the bacteria have enough time to reproduce);

4, inappropriate cooling of food (excessive cooling time);

5, improper heating of food (incomplete heating or prolonged heating at low temperatures);

6, poor housekeeping (accidental contamination accidents);

7, cross-contamination (inadequate hygiene systems, poor personal hygiene practices);

8, improper thawing of food (thawing at room temperature);

9, food processing or preparation personnel are infected and have poor hygiene practices;

10, contamination of processed food.