How to protect solder? What's the harm to your health?

Research progress of occupational hazards in welding operations 1, hazards and influencing factors of welding operations There are many health hazards in welding operations, which can be generally divided into two categories: physical factors and chemical factors. The former includes ultraviolet and infrared rays generated by high temperature arc light. The latter is various components of welding aerosol, including solid metals such as iron, manganese, aluminum, chromium, lead, nickel and radioactive elements, and gaseous gases such as manganese oxide, hydrogen fluoride and nitrogen oxides [1]. High temperature, vibration and noise are not obvious. Welding aerosol has high dispersibility and its biological activity is obviously higher than other dusts. Covered electrode and welding methods are different, the composition of welding aerosol changes greatly, and its biological activity is also different [2]; Biological activity is also related to the solubility and freshness of welding fume. 2. Damage of welding operation to workers' health 2. 1 welder's pneumoconiosis and lung function. During arc welding, the welding core, coating and metal base material in covered electrode are melted, evaporated, oxidized and agglomerated at the high temperature of arc, resulting in a large amount of dust of metal oxides and other substances, which can cause welder's pneumoconiosis if inhaled for a long time. Welder's pneumoconiosis generally occurs in a closed and poorly ventilated working environment, and the average length of service is about 18 years [3]. The measurement of lung ventilation function shows that exposure to welding dust can damage the lung ventilation function of welders to a certain extent, and the indexes of lung ventilation function such as FVC, FEV 1.0, FEV 1.0%, MMF, V50, V25 and PEFR are obviously reduced [4]. Smoking and dust exposure may have a synergistic effect on the pulmonary ventilation function of welders. The damage of lung ventilation function of welders tends to be aggravated with the extension of dust exposure time [5]. 2.2 Manganese Poisoning Various weldments and covered electrode contain different amounts of manganese. Generally, the manganese content in the cored wire is very low, only about 0.3~0.6%. In order to improve the mechanical strength, wear resistance, corrosion resistance and other properties, when covered electrode containing manganese is used, the manganese content can be as high as 23%. Welding in places with poor ventilation, such as cabins, boilers or closed containers, and long-term inhalation of manganese-containing smoke can cause manganese poisoning, which can detect manganese bleeding, increased urine manganese and changes in neurobehavioral functions [6]. The determination of manganese output can also be used as an early screening index for manganese poisoning [7]. 2.3 Welding smoke heat, also known as welder heat, is a kind of metal smoke heat. Systemic diseases caused by inhalation of metal oxides are characterized by sudden increase of body temperature and increase of peripheral white blood cell count, which usually begin at 6- 12 hours after exposure to metal oxide smoke, including dizziness, fatigue, chest tightness, shortness of breath, muscle and joint pain, followed by fever, leukocytosis and even chills. 2.4 Effects on the nervous system A large number of studies have shown that there is nervous system damage related to occupational exposure in welding operations, which mainly involves information processing functions such as memory, analysis and location, showing abnormal neurophysiology, neuropsychology and neurobehavior [9], which is closely related to manganese, aluminum and lead in welding dust. Use who. NCTB test showed that the total score of behavioral function was negatively correlated with urinary manganese [10], suggesting that the change of neurobehavioral function can be used as one of the early indicators to prevent manganese poisoning [1 1]. Foreign studies have reported that the total score of behavioral function of electric welding workers is higher than that of the control group. The author analyzes that it may be caused by the health effect of workers and the training effect of job-related skills [12]. The influence of electric welding on the investigation function of workers' parasympathetic nerves has also been reported [13]. It has been reported abroad that the onset age of welder's Parkinson's syndrome is obviously earlier [14] (the average age is 46 years old, and the average age of control group is 63 years old), suggesting that welding work is one of the risk factors of Parkinson's syndrome. 2.5 Effects on eyes and skin The harm of ultraviolet rays (UVR) and infrared rays (IFR) to eyes and skin is an important aspect of occupational injuries in welding operations. It is often reported that the eye symptoms of welders are obviously increasing, such as electro-optic ophthalmia, chronic blepharitis, conjunctivitis and lens opacity, and the prevalence of chronic blepharitis and conjunctivitis tends to increase with the increase of working years [15]. The main damage caused by UVR overexposure is photosensitive keratitis, and the welder's cataract is related to infrared exposure. Recent studies abroad show that workers exposed to excessive UVR are at risk of non-melanoma skin cancer [16] and other chronic diseases such as malignant melanoma of the eye [17]. 2.6 The impact on the reproductive system is significant. Therefore, in recent 10 years, some studies on the reproductive toxicity of electric welding have been carried out at home and abroad, mainly involving the semen quality of male workers, the reproductive outcome of female workers and the injury mechanism. The research shows that the menstrual flow, shortened cycle, prolonged menstrual period, increased leucorrhea, spontaneous abortion, premature delivery and dysmenorrhea of female welders are higher than those of the control group [18]. The semen appearance of male workers with manganese poisoning is even grayish white, and the PH value is normal. The average liquefaction time was longer than that of the control group. The results showed that the average ejaculation volume, total sperm count, sperm survival rate and activity rate of male workers with manganese poisoning were lower than those of the control group, and the sperm abnormality rate of male workers with manganese poisoning was significantly higher than that of the control group [19]. It is considered that manganese metal can affect the spermatogenic system of male workers, have a direct toxic effect on sperm development, and can kill sperm, thus causing changes in male semen quality. It has also been reported abroad that the sex hormone secretion of welders has changed and the sperm quality has decreased, but it has no effect on the sex ratio of offspring [20]. 2.7 Effects on the levels of enzymes and antibodies in vivo In recent years, there have been many reports on the effects of electric welding on enzymes and antibodies in workers. The results showed that the total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) in welders' serum decreased significantly, and the level of malondialdehyde (MDA) increased significantly, but there was no dose-effect relationship [2 1, 22]. When welders are under oxidative stress, their antioxidant capacity is weakened, indicating that the biofilm is destroyed [23]. In order to explore the influence of welding dust on human immunoglobulin content, the contents of IgG, IgA and IgM in serum of welders and healthy controls were determined by one-way immunoagar diffusion method. The results showed that the contents of IgG and IgA in welding group were significantly different from those in control group (P