Harm to lung: Dust is the most common harm to teachers' health. In the teaching process, chalk dust is easily inhaled into the lungs, and most of it is blocked in the alveoli. After a series of stimuli, chemical and immune effects can cause lung loss, including respiratory inflammation and decreased pulmonary ventilation function. Common lung diseases are: chronic and acute pneumonia, lung cancer, pneumoconiosis and so on. (that is, chalk dust contains silicon dioxide, which is inhaled into the lungs. Common lung diseases are.

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Harm to upper respiratory tract: chalk dust enters the lungs through the upper respiratory tract, including nose, pharynx and bronchus. In this process, some dust will stay in the upper respiratory tract, causing mechanical stimulation and damage to mucosal epithelial cells. Working in this environment for a long time will cause a series of pathological changes, among which the most common effect on the nose is to induce dry rhinitis, followed by hypertrophic rhinitis, which is characterized by dry nose, stuffy nose, congestion of nasal mucosa and increased secretion. The main effects on the pharynx are inducing chronic pharyngitis, making the pharynx dry, uncomfortable expectoration, sore throat and itching; The effect on bronchus is mainly to induce chronic bronchitis, sometimes asthma, and may also cause cancer of nasopharynx and bronchus.

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Injury to the eyes: The eyes are one of the most delicate and easily damaged organs of the human body. The main components of chalk ash, such as calcium carbonate and calcium oxide, are water-soluble substances, which are easily soluble in water and produce alkaline substances. For example, in the teaching process, chalk dust falls into the eyes, which stimulates the secretion of lacrimal glands, and tears hydrolyze calcium carbonate to produce alkaline substances, which will seriously stimulate the eye mucosa, cause mucosal damage, form chronic inflammation, and may also induce myopia.

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Harm to the skin: In the teaching process, chalk dust will inevitably get on the hands, and the particulate dust floating in the air will also fall on the teacher's hair, face and neck, which will stimulate the skin membrane. If you sweat and decompose in summer, it will produce alkaline substances, which will stimulate the skin mucosa more, because the environment of human skin is weakly acidic, which will destroy the basic living environment of skin under the action of dust alkalinity. Chalk dust makes the skin dry and rough, accompanied by itchy feeling, which makes people very uncomfortable. In severe cases, it can cause acne, folliculitis, pyoderma, chapped skin and a lot of hair loss, which affects and interferes with the normal work and life of teachers.

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Harm to ears: chalk dust enters the external auditory canal and mixes with sebum, which can form cerumen embolism. If it stays like this for a long time, it will cause ear inflammation.

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Chalk dust has a strong adsorption capacity, and many harmful bacteria can be adsorbed on fine dust and brought into students' lungs, thus contributing to the occurrence of acute and chronic inflammation, thus causing students to collectively infect respiratory tract and other epidemics. During the course of students' lectures, the indoor and total bacterial count and other sanitary indicators gradually deteriorate, which will interact with fine chalk dust and aggravate the harm of chalk dust to the health of teachers and students. The "lethality" of dust to teachers should not be underestimated.

Experts remind that teachers are advised to choose dust-free writing pens such as "environmental protection chalk" and "whiteboard pen" in teaching, which can effectively avoid the generation of dust in teaching. If you still use ordinary chalk, teachers should wash their hands in time after using chalk and pay attention to skin care, such as using skin cream appropriately. You can use eye drops properly at ordinary times, pay attention to eye hygiene, keep your hands clean, don't touch your eyes with dirty hands, stay away as far as possible when cleaning the blackboard, or hold your breath temporarily to reduce dust inhalation. The teacher's voice needs more care We should not only ensure adequate sleep and rest, so that the function of the vocal organs can be restored after a hard day's work, but also pay attention to the weather changes in peacetime, keep the oral cavity clean, quit smoking and drink less, eat less overheated, supercooled and spicy food, talk as little as possible when you feel uncomfortable in your throat, run more and play more games in peacetime, and strengthen your physique. The most important thing is to change the usage habits of traditional chalk. Only by unplugging the "root" that causes occupational diseases can the harm of chalk be completely solved.