Among the most important types of food poisoning are : Microbial poisoning, chemical poisoning, and natural poisoning. Microbial poisoning occurs because of several factors, microbial and non-microbial, resulting in poisoning cases individually or collectively, while people get food poisoning from eating food that contains large numbers of pathogenic microbes or toxins, or both, which is most prevalent. Chemical poisoning occurs as a result of eating food contaminated with chemicals such as pesticides, and natural poisoning occurs as a result of eating poisonous food in nature, such as some living sea organism  and plants.

There are various sources of micro-organisms food contamination, it may be from man, or water, or insects, rodents, or soil, or surfaces that contact food.

The symptoms of microbial poisoning are nausea, vomiting, diarrhea, headache, fever, and abdominal cramps, and symptoms of poisoning show on the person during 8-48 hours.

Steps to Prevent Food Contamination While Shopping

1. Make sure that the shopping place is clean, and that shopping stores are interested in keeping their products hygienic.

2. Separate your shopping cart purchases, and separate cleaning , disinfection materials and pesticides from food; put raw meat and poultry in plastic bags to prevent leakage.

3. Make sure of the safety of canned food. Cans and containers shall not be rusty or worn out or torn, or swollen or not tightly sealed.

4. Read the label on food item with care, to see the components of food, value and methods of preservation guidelines and allergy warnings, and make sure of the expiration date.

5. Avoid buying fruits and vegetables, that show bruises , damage or insect or fungal infections.

6. When buying meat, poultry or fish, make sure they are packaged well, and should be frozen and solid and do not have any snow on the corners because if this occurred; that means it was de-frozen and re-frozen again.