Explaining the Common Health Effects of Welding Fume.
In the UK, the Health and Safety Executive (HSE) is currently focusing on businesses that undertake welding within their workplaces. They're enforcing against non-compliance with the COSHH Regulations and issuing improvement and prohibition notices to those who are non-compliant. So, where does Workplace Scientifics fit in here? Well, our job is to advise and support you so that you don't fall short of your moral and legal obligations. With our regular article and blog updates and free resources that's exactly what we are doing.
Regardless of our purpose, it's important for you to know that exposures to welding fume are heavily linked with Cancer of the lungs and the kidneys. It's fair to say that there are many people across many industries who simply aren't aware of this.
How do we know this? Well, as occupational hygienists we operate in almost every work setting and we are often presented with questions such as:
Why is welding fume so topical at the moment?
What can welding fume do to the body and why do we now need stricter controls?
We've been welding for years, why all of a sudden the big push to tighten controls?
What is welding fume and what is it made up of?
What comes to light as we go about our work is that across many industries there's a lack of understanding around welding fume and its effects on the human body. Ultimately, this leads to BIG problems as we often find people and business owners not taking the subject seriously and, as a consequence, operatives are not provided with a suitable level of control nor do they understand why these controls are needed or how to use them.
To answer your questions, we have put together a series of articles that will help you understand things in more detail. In article number Two of Four, our objectives are to:
Outline the common constituents that makeup welding fume, explaining where these are likely to be present.
Provide a deeper level of awareness around welding fume and explain the effects on the body following inhalation.
Explain how the body reacts to various constituents based on detailed toxicological data, presenting us with possible health effects as a consequence of heightened exposures.
With this information you can begin to understand the importance of maintaining suitable levels of control allowing you to understand what constitutes a safe working environment in relation to the application of various welding processes. In addition to this, you can use your further knowledge to communicate and share important information with your industry, helping build a greater level of awareness as a whole.
Remember, by sharing this information, together we are creating safer working environments and encouraging others to adopt a safety-driven culture.
Common Welding Fume Constituents and Their Health Effects
To recap from a previous article Basics of Welding Explained, Welding Fume is airborne particulate and gases which are emitted into the atmosphere during welding operations. These particles mixed within the gases solidify in the air and become inhalable. Welding fume particulate can be a mixture of various particulate sizes, often distinguished as Inhalable Fractions and Respirable Fractions.
The particles emitted will vary depending on what materials are being welded during the process. Here are the more common constituents and their health effects:
The respiratory system is prone to irritative effects as well as more serious damage to the lungs following inhalation of elevated dust concentrations. There is further evidence of neurotropic to a neurotoxic action potential. An acute injury can occur as dust irritate the mucosae of the eyes and can cause corneal necroses. Studies of Aluminium dust and fumes showed that exposures caused chronic interstitial pneumonia or interstitial fibrosis also known as Aluminosis.
Exposure to copper fume can cause upper respiratory tract irritation, metallic taste, nausea, and metal fume fever. Metal fume fever is characterised by flu-like symptoms such as chills, fever, nausea, and vomiting.
The primary acute effects of exposure through inhalation are irritation of paranasal sinus and nasal cavity, throat and lungs. Exposure to the iron fumes can cause metal fume fever. It has been shown that iron-containing particles can be retained and accumulated in the lungs as a result of long-term exposure through inhalation mainly in the form of iron oxide fumes which can cause iron pneumoconiosis.
Manganese can affect the central nervous system. Health effects can include behavioural changes or movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as "manganism." The inhalation of a large quantity of dust or fumes containing Manganese may cause irritation of the lungs which could lead to pneumonia. Loss of sex drive and sperm damage has also been observed in men following high-level exposure.
Nickel is known to cause allergic reactions on the skin. People can become sensitised to Nickel, resulting in conditions such as allergic contact dermatitis. The International Agency for Research on Cancer (IARC) has determined that some Nickel compounds are carcinogenic to humans and that metallic nickel may possibly be carcinogenic to humans.
Chromium and Chromium III can be emitted by welding particular materials. Health effects include irritation of the lining of the nose, runny nose, and breathing problems (asthma, cough, shortness of breath, wheezing). Workers have also developed allergies to chromium compounds, which can cause breathing difficulties and skin rashes.
Hexavalent Chromium compounds, also known as Chromium VI, have been shown to cause lung cancer in humans. These stochastic effects have been shown to occur following exposure across specific industries. The International Agency for Research on Cancer lists hexavalent chromium compounds as known human carcinogens. Studies have consistently shown increased lung cancer rates in workers who were exposed to high levels of Hexavalent Chromium.
As a key discussion point of this article is the onset of occupationally related cancer, it would be prudent to highlight that the main target organ, in this case, is the lung. The International Agency for Research on Cancer (IARC) has designated Chromium VI as Category 1: Carcinogenic to Humans. This is especially the case if the substance becomes airborne and inhaled where a causal link between long term exposure and the onset of lung cancer has been identified. It may also be noted that there have been associative links observed between exposure to Chromium VI and nasal cancer.
Personal exposure is known to occur among employees who handle chromate-containing products as well as those who grind and weld stainless steel. Workers who are exposed to Chromium VI are at increased risk of developing lung cancer, asthma and damage to the nasal epithelia and skin.
The latency period between exposure to Chromium VI and the onset of lung cancer can be up to 20 years.
Exposure to zinc oxide can cause ‘metal fume fever’, as previously mentioned this is an illness known for its flu-like symptoms. Welders who work with thermal cutting, welding, and melting are often exposed to zinc oxide which is produced in the fumes when certain metals are heated, for example, Galvanised Steel is coated in Zinc of which is emitted as part of the fume when welding takes place.
Cadmium Oxide Fume
Exposure to Cadmium Oxide Fume can result in sore eyes, an irritated nose and throat, coughing, headache, dizziness and weakness, chill, fever, chest pains and breathlessness. Cadmium oxide compounds have been shown to cause cancer in animals. This has not been proven to occur in humans but employers are required to handle Cadmium Oxide as though it can cause cancer. It is considered that human exposure to cadmium chloride may result in impaired fertility or harm to the unborn child.
Beryllium is a metal that can be harmful when inhaled. When inhaled, beryllium can damage the lungs. When large amounts of soluble Beryllium is breathed in the lung damage can resemble pneumonia with the reddening and swelling of the lungs. This condition is called acute beryllium disease. Some people can experience an allergic reaction to Beryllium, resulting in an inflammatory condition which causes granulomas (benign lumps caused by the inflammation) in the lungs. These can cause people to feel tired, lethargic and weak. These can also cause people to have difficultly breathing.
The health hazards associated with exposure to vanadium are dependent on its oxidation state. This product contains elemental vanadium. Elemental vanadium could be oxidised to vanadium pentoxide during welding. The pentoxide form is more toxic than the elemental form. Chronic exposure to vanadium pentoxide dust and fumes may cause severe irritation of the eyes, skin, upper respiratory tract, persistent inflammations of the trachea and bronchi, pulmonary oedema, and systemic poisoning.
Acute effects of exposure to Fluorides include irritation of the eyes, nose and throat. Long-term exposures may result in bone and joint problems. Chronic effects also include excess fluid in the lungs developed through repeat inhalation of the substances.
Welders have been known to experience pulmonary problems such as asthma, pulmonary inflammation, hyper-responsiveness of airways relating to occupational exposure. They also have a higher susceptibility to infections which have been reported as the result of inhaling Nitrogen Oxides emitted by welding processes.
Carbon Dioxide is a simple asphyxiant. This means that the particles can out quantify oxygen in a given atmosphere, preventing the body to uptake oxygen upon inhalation, resulting in asphyxiation. Inhalation in excessive concentrations can result in dizziness, nausea, vomiting, loss of consciousness and death.
Volatile Organic Compounds
Usually present as a result of using pre-cleaning and metal treatment agents on the workpiece before welding. The welding process then causes volatile substances to be emitted into the atmosphere. Common effects of VOC's are their ability to cause neurological damage, suppress the nervous system and further damage target organs, such as the liver and kidneys.
Ozone is created when oxygen reacts with ultraviolet light (UV). In welding, the light is created by the arcing process, where the metals are melted and pooled and the filler infilled. The oxygen then reacts with the UV, resulting in the generation of Ozone. Ozone is irritating to the throat and airways and can cause violent coughing, wheezing and breathing difficulties. The substance returns back to its original state as oxygen soon after the reaction.
Like Carbon Dioxide, Argon is a simple asphyxiant. Again, this means that the particles can out quantify oxygen in a given atmosphere, preventing the body to uptake oxygen upon inhalation, resulting in asphyxiation. Inhalation in excessive concentrations can result in dizziness, nausea, vomiting, loss of consciousness, and death
Back in February 2019, the Health and Safety Executive (HSE) published the document STSU1 2019 titled: Changes in Enforcement Expectations for Mild Steel Welding Fume. In this bulletin it is outlined that there has been new scientific evidence from the International Agency for Research on Cancer (IARC) that exposure to mild steel welding fume can cause lung cancer and possibly kidney cancer in humans and, as such, has been reclassified as Category 1: Carcinogenic to Humans.
Under this reclassification, the HSE have noted that regardless of duration, they will no longer accept any welding to be undertaken without any suitable exposure control measures in place. This is due to there being no known level of safe exposure.
Finding Out More About Carcinogenic Substances and Why COSHH is Important
Want to learn more about common Carcinogenic Substances? Why not take a look at our past articles written on the run-up to world cancer day. Check them out below.
Introducing Wood Processing
Diesel Engine Exhaust Emissions Awareness
Styrene Exposure Linked with Occupational Cancer
We are here to help. As professional Occupational Hygienists, we are competent in managing COSHH and providing a range of assessments to help you quantify exposures and test control systems. Contact us today for more information:
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