The fumes can come from the base materials being welded, from the welding rod/wire, from the welding filler metals, and from the coatings of the base material (material to be welded).
The base material or welding rod/wire could produce fumes containing Iron oxide, Manganese, Nickel or Chromium or a combination.
The coatings include Cadmium used to coat steel, paint used to coat other metals; if coated with Cadmium, the fumes will contain Cadmium but if coated with paint, the fumes will contain Lead.
The effects of welding on the welder depend on the material being welded including the coating, the welding space (enclosed or open) and also the preventive measures taken by the welder.
Injuries could be cuts or blunt, cuts could occur while handling the item to be welded or when trying to amend it by cutting before welding it. Blunt injuries can occur while hitting the item to either straighten it or flatten it in preparation for welding.
2. Irritation of the respiratory tract
If Iron is being welded, the fume will contain Iron oxide which is a great irritant to the nose, throat, trachea and lungs. This could lead to opportunistic infections of the parts mentioned.
If the base material is steel, the fume will contain Chromium and Nickel; the latter will trigger asthmatic attack in an asthmatic while the former will aggravate or cause sinusitis (inflammation of the sinuses, these are spaces in the bones our face)
3. Damage to the eyes (blurred vision and burning sensation in the eye)
Welding produces “glaring light” due to Ultra violet light of welding, if the eyes are unprotected by the use of goggles/face shield, the cornea of the eye can be affected. This is characterized by blurred vision and burning sensation in the eye; the damage is reversible but if the exposure is persistent and prolonged, the damage could be permanent.
4. Hearing loss
Welding causes a lot of noise which could be above permissible noise level, this exposure if persistent could lead to hearing loss (partial deafness).
Welding produces a lot of heat, this is worse if the welding is done in an enclosed space. The heat exposure could result in Heat rash, Heat collapse, Heat cramps, Heat Exhaustion or Heat stroke. The last is life threatening.
6. Respiratory diseases
Respiratory diseases from welding are due to inhaled fumes and the disease depends on the fumes inhaled; if the base material is steel the fume will contain Cadmium which can cause a lung disease called Emphysema, Cadmium is used to coat steel to prevent rust. The fume from steel also contains Nickel which can trigger asthmatic attack in an asthmatic, the same fume also contain Chromium which can cause sinusitis. If the welding rod contains Asbestos, then the fume will contain Asbestos which can cause a lot of diseases in the lungs including cancer if exposure is for several years.
7. Neurological diseases
Welding could cause a lot of damage to the brain and nerves if the fumes contain Manganese and/or Lead. Manganese can be from the base metal or the welding rod while the Lead is from the paint coating. The damage due to Manganese is characterized by slowness of movement, poor balance, shaking of the hands (tremors), muscle stiffness, poor co-ordination, poor memory and so on.
Welding can cause burn to the hands if done without wearing gloves
9. Kidney problems
The effects on the kidneys are due to Cadmium and Lead fumes. The Cadmium as said earlier comes from steel coating while the Lead comes from paint coating.
The kidney damage from these fumes could lead to kidney failure and of course death.