Lung Disease and Work

The Lane Lecture is an annual event hosted by the Centre for Occupational and Environmental Health at the University of Manchester. Named in honour of Ronald Lane, the first ever Professor of Occupational Health at the University.

This year the lecture was delivered by Professor David Fishwick, Chief Medical Officer and Co-Director of the Centre for Workplace Health. His talk was entitled The lungs at work: from cotton mills to composites? One of the key messages is that diseases such as byssinosis and silicosis are not historic issues.

In 1890 there were more cotton mills in Manchester than in the rest of the world. But that is no longer the case – the industry has been transferred overseas, particularly to developing economies. So byssinosis, which is caused by exposure to cotton dust, is no longer a problem in the UK. However, it’s a different matter in those countries where cotton is now produced.

Studies carried out in recent years have shown high incidences of byssinosis in some mills in developing countries. One study in Karachi, Pakistan in 2008 found that among 362 textile workers 35.6% had byssinosis. (Prevalence of Byssinosis in Spinning and Textile Workers of Karachi, Pakistan, Archives of Environmental & Occupational Health, Vol. 63, No. 3, 2008 )

Professor Fishwick also focused on Silicosis, the oldest known occupational lung disease which remains a significant problem across the globe, including the UK. This debilitating disease is caused by exposure to respirable crystalline silica (particles smaller than 10 microns) which can occur in many industries, including mining, quarrying, brick and tile manufacture, stone masonry, glass manufacture, tunnelling, foundries, ceramic manufacturing and construction activities.

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The risk is clearly associated with the level of exposure and it only takes a regular exposure to very low concentrations to cause the disease. The US Occupational Safety and Health Administration (OSHA) estimates that 30% of workers with 45 years of exposure to 0.1 mg/m3 respirable crystalline silica dust will develop silicosis (see page 16394 of the “Final Rule”). Yet 0.1mg/m3 (respirable dust) is the current Workplace Exposure Limit for crystalline silica in the UK.

Clearly the current WEL is not a “safe level” and there is a very strong case for reducing it. In the US OSHA has recently announced a reduction in their Permitted Exposure Limit for silica down to 0.05 mg/m3. No change is proposed in the UK. The HSE’s view is that there are difficulties accurately measuring exposures lower than 0.1mg/m3, so it would be difficult to demonstrate compliance, and that, in any case, employers have a duty to not only meet the exposure limit but the apply “principles of good control practice” set out in Schedule 2A of the Control of Substances Hazardous to Health Regulations. Not everyone agrees with them, however.

As well as causing silicosis, respirable crystalline silica is a carcinogen. It’s estimated that in the UK it causes around 600 deaths per year from lung cancer shows  with 450 of these occurring from exposures in the construction sector.

Occupational cancer deaths by cause in Great Britain, 2005 (HSE)

Personally, I’d like to see the WEL reduced and research done to develop better sampling methods which will allow low levels of exposure to be evaluated. I do sympathise, though, with their emphasis on control. Reducing exposure by introducing improved controls is the key to preventing workers from developing industrial disease. Measurement can help us to understand exposure and identify where improved controls are needed. But sometimes the problem is obvious and in those cases it’s better to spend time, effort and money sorting it out, particularly when there are well established solutions available.

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Dark Satanic Mills

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Many people when they get to a certain age start to wonder where they came from. That was certainly true for me so a few years ago I started to research my family tree. Although there were a few surprises my research confirmed that I my family were ordinary workers. I wanted to find out about my roots, about my ancestors, where they came from and how they lived. And as an occupational hygienist I couldn’t help but be interested in what they did for a living and their working conditions.

Halifax Mill Chimneys

Coming from Lancashire it wasn’t a surprise to find that many of my ancestors who lived in the 19th and 20th Centuries were employed at some time during their lives in cotton mills. And working in cotton mills they were faced with a whole host of health risks.

I’ve always been interested in industry and when I was a boy my mother arranged for me to have a look round the mill where she worked. The first thing that hit me when I walked in the mill was the tremendous noise. Levels in weaving sheds were likely to be well above 90 dBA – often approaching, or even exceeding 100 dB(A). Communication was difficult and mill workers soon learned how to lip read and communicating with each other by “mee mawing” – a combination of exaggerated lip movements and miming

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Not surprisingly many cotton workers developed noise induced hearing loss – one study in 1927 suggested that at least 27% of cotton workers in Lancashire suffered some degree of deafness. Personally, I think that’s an underestimation. This is how the term “cloth ears” entered the language – it was well known that workers in the mills were hard of hearing.

This lady is a weaver and is kissing the shuttle – sucking the thread through to load the shuttle ready for weaving.

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This practice presented a number of health risks – the transmission of infectious diseases, such as TB, but as the shuttle would be contaminated with oil, and the oils used then were unrefined mineral oil – there was a risk of developing cancer of the mouth.

Exposure to oil occurred in other ways particularly for workers who had direct contact with machinery or where splashing of oil could occur. There was a high incidence of scrotal cancer in men who operated mule spinners – and this was a problem even in the 1920s. In earlier times workers in mills had to work in bare feet as the irons on their clogs could create sparks which could initiate a fire due to the floorboards being soaked with oil. Contact with these very oil soaked floorboards led to cases of foot cancer.

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And of course there was the dust. Exposure to cotton dust, particularly during early stages of production, can lead to the development of byssinosis – a debilitating respiratory disease. An allergic condition, it was often known as “Monday fever” as symptoms were worst on Mondays, easing off during the week. A study on 1909 reported that around 75% of mill workers suffered from respiratory disease.

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The worst areas for dust exposures were the carding rooms where the cotton was prepared ready for spinning, but dust levels could be high in spinning rooms too.

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Although control measures started to be introduced in the 1920’s workers continued to be exposed to dust levels that could cause byssinosis. Studies in the 1950’s showed  than more than 60% of card room workers developed the disease as well as around 10 to 20% of workers in some spinning rooms.

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A lot of work was devoted to studying dust levels, developing standards and control measures by the early pioneers of occupational hygiene in the UK and I’m sure this contributed to improved conditions in the cotton industry in the UK. I’m not sure I’d like to have to operate their dust sampling kit though – it certainly wasn’t personal sampling!

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Today things are different. The carding machines, spinning frames and looms are silent and have been sent for scrap. The mills have been abandoned and are derelict or demolished or have been converted for other uses.

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Cotton is still in demand but it’s a competitive market and the work has been moved to other countries where labour is cheap and standards are not as high – Africa, China and the Indian sub-continent. Another consequence of globalisation. Although you could say that the industry is returning to where it originated in the days before the industrial revolution. Sadly, conditions and working methods in many workplaces in the developing world are primitive and controls are minimal. It seems like the lessons learned in the 20th Century in the traditional economies are rarely applied so not surprisingly those traditional diseases associated with the industry are re-emerging in developing economies.

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Studies carried out in recent years have shown high incidences of byssinosis in some mills developing countries. One study in Karachi, Pakistan in 2008 found that among 362 textile workers 35.6% had byssinosis. (Prevalence of Byssinosis in Spinning and Textile Workers of Karachi, Pakistan, Archives of Environmental & Occupational Health, Vol. 63, No. 3, 2008 ). A study of textile workers in Ethiopia published in 2010 showed a similar proportion – 38% had developed byssinosis,  with 84.6% of workers in the carding section suffering from the disease

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Another study, this time into textile workers’ noise exposures in Pakistan indicated noise levels in the range 88.4-104 dB(A). 57% were unaware that noise caused hearing damage and almost 50% didn’t wear ear defenders

William Blake wrote of “Dark Satanic Mills” in 1804. This was still a fair description of the working conditions in Lancashire when my ancestors worked in the mills. And I believe its valid today in many workplaces in the developing world.

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It’s not easy to get accurate figures on occupational health in the UK and so much more difficult in the developing world. The best estimate we have (and it’s likely to be an underestimate) is that 2.3 million people die due to accidents at work and work related disease (World health Organisation). And the vast majority of these are due to ill health

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Some occupational hygienists might take a dispassionate, academic interests in dust exposure. But I think most of us are motivated by a genuine desire to prevent ill health at work and improve working conditions. Many of us work in countries where conditions although far from perfect are relatively good. But can we turn a blind eye to what’s happening in the rest of the world?

Personally, I think it’s something we need to be thinking about.