The lead content of preserved eggs made by traditional technology is high, because lead oxide is used in the production process, which will play a sealing role and block the small holes on the surface of preserved eggs, thus preventing strong alkali from further reacting with protein. With the progress of technology, after 2008, the state issued a new standard for preserved eggs, which stipulated the lead content.

Nowadays, regular manufacturers have begun to use the "lead-free process" to make preserved eggs, that is, zinc chloride or copper sulfate is used instead of lead oxide, which can reduce the lead content and also seal the holes. According to the information released by the State Administration of Market Supervision in recent years, the sampled preserved egg products rarely have lead exceeding the standard. In short, as long as the preserved eggs meet the national standards, they can be safely eaten.

The following people fast preserved eggs:

1, growing children.

Lead in preserved eggs, absorbed by children during their growth and development, will stay in tissues such as liver, lung, kidney, brain and red blood cells, leading to calcium loss in bones and teeth, causing adverse effects such as stunting, anorexia and gastroenteritis in children, and even affecting intellectual development and nervous system. Once the damage is formed, it will be irreversible.

2. Pregnant women.

Heavy metals such as lead and arsenic in preserved eggs have a great influence on pregnant women and fetuses, which can easily lead to abortion, premature delivery, fetal malformation, malnutrition, delayed brain development, mental retardation, behavioral defects and other hazards. Pregnant women should eat as little or no preserved eggs as possible.

3. Sick patients.

Preserved eggs are easily contaminated by Escherichia coli and Salmonella. The weak patient group has poor resistance and is easy to be infected by bacteria, causing various intestinal diseases; Sensitive people may have symptoms of food poisoning; Moreover, preserved eggs are cold, and people with spleen and stomach deficiency and cold can easily cause diarrhea after eating them. It is suggested that the frail patients eat less or not.

4. People with liver diseases.

Liver is the detoxification organ of human body, but it can't decompose and metabolize heavy metals. Excessive consumption of preserved eggs by patients with liver disease may cause heavy metal poisoning and affect the nervous system and digestive system. In addition, preserved eggs are rich in protein, which will produce a lot of amino acids after decomposition. If patients with liver disease eat too much at one time, it may lead to ammonia poisoning and hepatic coma, and in severe cases, it may lead to death.

5. People with hypertension.

Preserved eggs have a high sodium content, which is five times that of ordinary eggs, but there is no difference in cholesterol content compared with ordinary eggs. Patients with hypertension should try to eat less.

Reference to the above content: People's Daily Online-Is the preserved egg safe?

Reference to the above content: People's Network-Five groups of people eat preserved eggs carefully