WELDING FUME: A KNOWN CARCINOGEN

WELDING FUME: A KNOWN CARCINOGEN

A closer look at the recent reclassification of welding fume as Group 1: Carcinogenic to Humans

Onwards

There is no doubt that the recent reclassification of welding fume as carcinogenic to humans by the International Agency for the Research on Cancer (IARC) has encouraged many welders and workplaces to rethink their stance on welders’ respiratory protection. This white paper aims to investigate the recent reclassification from an Australian perspective pulling relevant information from multiple sources into one easy to read document. So that employers of welders and welders themselves can make better decisions regarding welding fume and suitable respiratory protective measures. This paper also attempts to raise awareness of workplace cancer risks associated with welding so that welders question and challenge whether they are suitably protected even when operating under the current Australian workplace exposure standards for welding fume.

What has changed?

As you may already be aware, in March 2017, scientists from around the world met at the International Agency for Research on Cancer (IARC; Lyon, France) to evaluate the carcinogenicity of welding fume. Based on substantial new evidence through observational and experimental studies, welding fume has now been reclassified from “possibly carcinogenic to humans” as it was originally classified in 1989 to its new Group 1 classification as “Carcinogenic to Humans”. The working group concluded that there is “sufficient evidence in humans” that welding fumes cause lung cancer and limited evidence for kidney cancer.

Categorisation Explained

“Group 1” or “Category 1A” in Australian terms has the following description as outlined in “the guidance on the interpretation of workplace exposure standards for airborne contaminants” by Safe Work Australia:

CATEGORY 1A – KNOWN TO HAVE CARCINOGENIC POTENTIAL FOR HUMANS Substances known to have carcinogenic potential for humans are substances for which there is sufficient evidence to establish a relationship between human exposure to these substances and the development of cancer

What are the current Australian Workplace Exposure Standards for welding fume and what do they mean?

“In addition to complying with the exposure standards for specific contaminants, the fume concentration in the breathing zone (which is inside a welder’s helmet when a helmet is worn) must not exceed 5 mg/m3 using a TWA”3 (Time Weighted Average). This means that the maximum average airborne concentration of total welding fume when calculated over an 8-hour working day, over a five-day working week, must not exceed 5 milligrams of substance per cubic metre of air. In addition to this general exposure standard, there are then specific exposure standards for particular types of chemicals. Below we list the most common fumes and chemicals workers may be exposed to when welding and the respective health effect as well as the TWA exposure limit released by Safe Work Australia:

Australian Workplace Exposure Standards

How revisions of Australian workplace exposure standards are done in light of the recent reclassification of welding fume

“The guidance on the interpretation of workplace exposure standards for airborne contaminants” released by Safe Work Australia very clearly states that “exposure standards are updated occasionally and may not always reflect the latest research or state of knowledge on the hazardous effects of chemicals. Classifications may become out-dated and incorrect where new information about a substance’s hazards becomes available. Exposure standards do not identify a dividing line between a healthy or unhealthy working environment and are only provided for information purposes to help minimise exposure. Therefore, exposure standards should not be considered as representing an acceptable level of exposure to workers. They establish a statutory maximum upper limit”3. As a result, it’s important to note that the current Australian exposure standards should only be taken as a starting point and they have not been revised since the reclassification of welding fume by the IARC.

Are Aussie welders safe when operating under the exposure standards?

Based on the typical respiratory rate of 20 litres of air per minute or 2,300 m3 of air per year, a welder operating within the workplace exposure standards for general welding fume (5 mg/m3), wearing no respiratory protection could inhale up to 11 grams of welding fume per year. So year on year, an unprotected welder operating within the workplace exposure limits can inhale 11 grams of a now known, identified and classified carcinogen.

How do Australia’s workplace exposure standards stack up with the rest of the world?

In Germany, there is a regulation translated as “Technical Rules for Welding Applications” (TRGS 528) which is based on the TRGS 900 Exposure Limits. Currently the exposure limit and regulation for general dust or nonspecified welding fume (where no other specific exposure limit exists for that substance) is 1.25 mg/m3. All German exposure limits are monitored and revised (if necessary) every two years to give the best possible picture of the hazards and associated risks. Therefore an Australian welder operating under the legal workplace exposure limits (5 mg/m3) for welding fume in Australia is exposed to 4 times the level of a known carcinogen than that of a German welder working under the TGRS 528 (1.25 mg/m3) regulation in Germany.

Have there been any recorded cases in Australia where a solid link between welding and cancer was established?

“Around 5,000 cases nationally every year are linked to workplace carcinogens, with an estimated 3.6 million Australians exposed to cancer-causing agents at work”. In 2014, theage.com.au reported on an Australian first linking a Melbourne man’s deadly lung tumor to toxic welding fumes. “Anh Tran, a 54-year-old ex-smoker whose right lung was surgically removed, won Workcover compensation after a court ruled that working as a welder had raised his risk of contracting lung cancer”. “The Victorian County Court ruled in favor of Mr. Tran in light of testimony from medical experts that former welders were 44 percent more likely to contract lung cancer compared to people who have never worked in the field”. “It was the first time in Australia that compensation had been awarded due to a link between lung cancer and welding fumes”, opening the door for future compensation claims.

What should you do as an Employer to ensure welder's safety in their workplace?

The employer has the primary responsibility to ensure that welders, as far as reasonably practicable, are not exposed to health and safety risks whilst performing their job. If it is impossible to eliminate the risk entirely the employer must minimise the risk as far as reasonably practicable by introducing engineering or administrative controls such as ventilation and the use of personal protective equipment such as welding powered air respirators or supplied air respirators. Welders must be informed of the risks and be a part of the decision-making process to draw on their knowledge and expertise to help select the most appropriate control measures including any personal protective equipment they may require. “Welders also have a responsibility to take reasonable care for their own health and safety. Welders must comply with any reasonable instruction and co-operate with any reasonable policy or procedure relating to health and safety at the workplace. If personal protective equipment is provided by the person conducting the business or undertaking, the worker must use it in accordance with the information, instruction and training provided”. “If there is any doubt that the controls implemented have been effective