Soldering iron solder to prevent chronic poisoning!
In essence, lead is a toxic substance. Lead (Pb), a gray-white metal, has an atomic weight of 207.20, a specific gravity of 11.34, a melting point of 327.5°C, and a boiling point of 1620°C. When heated to 400°C-500°C, a large amount of lead vapor will escape. And rapidly oxidized into lead oxide in the air, and condensed into lead dust. As the temperature of molten lead rises, it can be further oxidized into lead oxide, dilead trioxide, and trilead tetroxide, but they are all unstable, and finally dissociate into lead oxide and oxygen. Excessive absorption by the human body can cause lead poisoning. Ingestion of low doses may affect human intelligence, nervous system and reproductive system, that is, occupational lead poisoning, which is usually chronic. l, blood lead exceeds 50 μg/t, occupational history and clinical symptoms are the basis for diagnosis.
Occupational lead poisoning has clinical symptoms of nervous, digestive, blood and other systems:
1. Nervous system
The main manifestations are neurasthenia, polyneuropathy and encephalopathy.
Neurasthenia is one of the early and common symptoms of lead poisoning, manifested as dizziness, headache, general fatigue, memory loss, sleep disturbance, dreaminess, etc. Among them, dizziness and general fatigue are the most obvious, but generally mild , is a functional symptom. There are still many early lead poisoning patients, and the above symptoms are not obvious.
2. Digestive system
Mild cases manifest as general gastrointestinal symptoms, while severe cases present with abdominal cramps. Gastrointestinal symptoms include a metallic taste in the mouth, loss of appetite, epigastric distension and discomfort, abdominal pain and constipation, dry stools in the shape of abacus beads, and intractable constipation is often a precursor before the onset of lead colic. Abdominal colic is a sudden attack, mostly around the umbilical cord, and is persistent pain, which is aggravated during paroxysms, and each attack lasts from several minutes to several hours. Because the pain was severe and unbearable, he often bent his waist and knees, tossed and turned restlessly, and pressed his abdomen with his hands to relieve the pain. At the same time, his complexion was pale, his whole body was sweating cold, and he may have vomited.
3. Blood system
The main reason is that lead interferes with the hemoglobin synthesis process and causes changes in its metabolites, such as decreased blood δ-ALAD activity, increased urinary δ-ALA, increased urinary CP, increased blood FEP, ZPP, etc., and finally leads to anemia, mostly hypochromic normal red blood cell type anemia.
4. Other systems
Lead damage to the kidneys is more common in acute, subacute lead poisoning or severe chronic cases, amino acid proteinuria, red blood cells, white blood cells and casts and renal dysfunction, suggesting toxic nephropathy, accompanied by high blood pressure. Female workers are more sensitive to lead, especially during pregnancy and breastfeeding, which can cause infertility, miscarriage, premature delivery, stillbirth and lead poisoning in infants. Male workers can cause decreased sperm count, decreased activity and morphological changes. In addition, it can still cause hypothyroidism.
Lead-free solder wire is environmentally friendly, but lead-free solder wire is also harmful to the human body. The low lead content of lead-free solder wire does not contain lead. Compared with lead-containing solder wire, lead-free solder wire is harmful to the environment and human body. Pollution is less than leaded. The gas produced during soldering is still toxic, and there are also gas vapors such as rosin oil and zinc chloride.
Precaution
1. When soldering components with electric soldering iron, use ROHS tin wire to reduce toxic factors from the root.
2. Pay attention to ventilation during the process to reduce the inhalation of solder vapor.
3. Strengthen personal protection. Personal protective equipment includes respiratory protective equipment (masks, face shields for dust and poison protection).
4. You must wash your hands after using the solder, do a good job in personal hygiene and cultivate good hygiene habits, and do not smoke or eat in the workshop.
5. Eat a healthy diet. In order to enhance the body's resistance, some special nutritional ingredients should be properly supplemented according to the nature and characteristics of the harmful factors of exposure to occupational lead. There are many components in food, which have the effect of chelating lead and resisting lead damage.
