By Angela Saward, BA, MTA (Wellcome Collection)
Dr. Mary Catterall (1922–2015), doctor and sculptor, script and medical adviser to the film, It Takes Your Breath Away, became concerned with lung health when she was appointed Senior Registrar in Respiratory Medicine at Leeds General Infirmary, England in 1960. The film won a Silver Medal at the British Medical Association annual film competition in 1964, which welcomed films from professional and amateur filmmakers, only specifying that medical excellence was paramount. It is a work of “hidden” cinema: it was devised specifically for professional medical audiences, in this case healthcare personnel, and was not intended to be distributed to the wider public. This essay looks at the backstory to the film and how Catterall became involved both personally and professionally by exploring her archives, held at Wellcome Collection where she deposited them in 2009, as well as other library and archival sources. The essay contributes to the growing interest and discourse around environmental activism in the 1960s across both sides of the Atlantic. Air pollution has historically taken a significant toll on health and mortality; at the time the film was made, it was implicated in 30,000 deaths in the UK. Today, comparisons can be made with COVID-19 when once again air pollution has become highly newsworthy: at the time of writing there is growing evidence that deaths through complications from COVID-19 have a direct causal relationship to exposure to harmful air particulates.
Today, comparisons can be made with COVID-19 when once again air pollution has become highly newsworthy: at the time of writing there is growing evidence that deaths through complications from COVID-19 have a direct causal relationship to exposure to harmful air particulates.
The Long Shadow of the Industrial Revolution
In Northern cities in the United Kingdom, the legacy of migration, rapid urbanization, and the attendant problems of pollution, which started with the Industrial Revolution, continued to have a detrimental impact centuries later. It Takes Your Breath Away references this legacy. It begins with opening credits of photographic still images of scenes showing various high-angle views of rooftops and chimneys from residential and industrial settings. The music is doom-laden and discordant. The title of the film, It Takes Your Breath Away, is at odds with the images: the received use of this phrase is “to astonish or amaze,” so the choice is immediately unsettling. Seven of the 13-minute running time is taken up with contextualizing visual material on the polluted urban environment coupled with a powerful narration, scripted by Catterall and voiced by Bryan Martin. The film’s position regarding pollution is clear: air pollution is a human problem (the subtitle to the film). The language is loaded; it refers to the influence of the Industrial Revolution on humankind by remarking, “mechanism spread like a rat.”
The film contrasts the “black towns” of the industrial North of England where smoke and dirt, chemicals, soot, and corrosive grime particles had damaged the urban environment to the newly planned Clean Air Zones, where gleamingly clean buildings such as St. Paul’s Cathedral in London were granted extensive and costly restoration. The clearly visible damage to the built environment is common in films on this subject, largely due to the readily quantifiable economic costs associated with cleaning up the problem. However, the film also makes reference to the social injustice of improving the environment in some areas such as the center of London (perhaps for the benefit of the few) to the detriment of mixed industrial/residential zones that already suffered under social and economic pressures, where factories and tenements historically were co-located.
“the air was thick with soot”
Left: a housewife wipes the window ledge, demonstrating the level of grime present. Right: a mother picks up her child at the bottom of a slide in a playground, finding the light-colored clothing besmirched with grit.
National Library of Medicine #101771068
The city of Leeds is a brooding presence in It Takes Your Breath Away, filmed, in Catterall’s words, in its “mourning black.” As a center of the woolen industry, it had prospered with both good transport links and proximity to coal fields, once being home to the largest woolen mill in the world. Subsequently, in the mid-twentieth century, the city experienced rapid economic decline as these industries faltered, although it was still England’s fifth-most populous city. The “scars” of the Industrial Revolution led environmental agencies to comment that peat in the surrounding area is “more acidic than lemon juice.” This legacy of relying on fossil fuels in industry as well as in the home was evident in the lungs of the city’s inhabitants as well. As Catterall recounted:
This was my first encounter with the North, and with the industrial pollution of the fifties and sixties. I was shocked. Buildings were black, car lights were necessary in the middle of the day, the air was thick with soot and smelt acrid. Air pollution came not only from factories and hospitals, but also from tens of thousands of domestic chimneys burning coal. Babies were put out in prams, from small back-to-back homes and after a single morning on the pavement, their faces were marked with soot and pram covers were filthy.
The Great Smog and Clean Air
Smog (a contraction of “smoke” and “fog”) had been a feature of the urban environment for nearly a century, with smoky chimneys and misty skylines forming the trademark of artistic representations of atmospheric city landscapes (especially of London). That was until the “Great Smog” of 1952, which affected the health of many vulnerable people already living with chronic lung conditions. It is widely agreed that this event alone led to at least 4000 people dying immediately with a further 8000 in the weeks and months afterward. These stark statistics led to a turning point when the medical effects of air pollution on health were irrefutable. Improving matters required a paradigm shift in energy usage. As a consequence, the 1956 Clean Air Act in the United Kingdom instituted changes in the use of fossil fuels in industry and the home.
Apart from the health implications of polluted air, the other benefits of using cleaner energy, once they became apparent, were also drivers for change. It was clear from the middle of the century that coal reserves in the United Kingdom were being depleted. Mining practices became more labor-intensive and less economically viable. Therefore, there was an incentive to become more fuel-efficient and find less wasteful sources of energy to power the nation in its post-war redevelopment. Cleaner electricity could be generated with modifications to homes and factories by refitting inefficient stoves, boilers and furnaces. This not only delivered economic benefits (in the form of savings), it created a new supply sector for energy-efficient equipment. In turn, the energy sector received an image boost due to the perceived modernity in promoting cleaner energy in the form of gas and electricity.
Catterall’s autobiography and the bias of the film paint a very negative picture of air pollution in Leeds and what was being done about it. Catterall’s writing is suffused with impatience at the pace of progress. Looking at the factual record, Medical Health Officer reports provide detailed analyses of the population of the area (births and deaths), epidemiology as well as health, food safety, and sanitation provision. From 1919, when the Ministry of Health was established in the United Kingdom, local authorities gained more control over the provision of healthcare services to their populations, and Medical Health Officers were mandated to collate and report relevant statistical data. This became standardized across the annual reports submitted to the Ministry. In fact, although air pollution was worrisome in Leeds, something was being done: from 1956, data on air pollution was being tracked, and there was surveillance equipment to monitor the air pollution in the city, regulatory power to create smoke-free zones, to respond to complaints of smoke (or noise) pollution, and levy fines on businesses that were non-compliant.
Left: Medical Officer of Health Reports, 1958. Map of Atmospheric Pollution showing ‘hot spots’. Right: Medical Officer of Health Reports,1965. Resultant drop in air pollution when homes are brought into Smoke Control Areas.
Courtesy Wellcome Collection.
The Leeds Incorporated Chambers of Commerce had been very concerned about all the ramifications of the Clean Air Act and published a supplement on clean air for The Leeds Journal in 1956. Largely technical in nature it comprised sixteen chapters, and it ran advertisements from purveyors of industrial boilers and domestic heating equipment, with such slogans as such as “No Need for ‘Scrubbing’/Towards a Cleaner Atmosphere” (Yorkshire Electricity Board), “Let’s Make This Quite Clear Says Mr. Therm/GAS & Coke End Waste & Smoke” (North Eastern Gas Board), and “Are You Guilty of Atmospheric or Water Pollution?” (Royal Doulton Chemical Stoneware). The supplement was produced with funds from the National Industrial Fuel Efficiency Service amongst others and is indicative of the collective effort to improve air quality. The anti-pollution lobby was led by the Coal Smoke Abatement Society (CSAS), established in 1898. Later renamed the National Society for Clean Air (NSCA) when the menace from coal smoke receded, it became more vocal about air pollution from industry and transport. The organization was involved in various environmental concerns until it stopped operating in 2012 (by this time as Environmental Protection UK). The Coal Smoke Abatement Society created propaganda to communicate its message in the form of a quarterly newsletter, Smokeless Air, and various other information resources, but its efforts were very small in changing public opinion.
Mary’s self-published account of her life and career is filled with examples of professional slights and major disagreements with paternalistic, male medical professionals. Her voice, though vehement at times, is an important testament to the minoritized views of the time of a female clinician working in an overwhelmingly male profession. Mary was born Eileen Mary Williamson in 1922 in England and she began her medical career in 1941 during World War II. Reading between the lines, a career in medicine was not available to her as she did not have the requisite education (she writes that her parents were hoping for a boy, there was already an older female sibling). One profession open to her was physiotherapy: she duly qualified as a physiotherapist in 1943. Unfortunately, she actively disliked the work, but as it was a protected position of national importance, she found herself stuck professionally until after the war whilst she studied for entry exams for medicine via a correspondence course. In 1947 when she entered the London Hospital Medical School, she was only one of seven women in a class of 77, reflecting the gender imbalance in the profession at the time.
Taking a novel approach, Mary developed and patented an improved oxygen delivery mask, the New “MC” Oxygen Mask for “Effective Oxygen Therapy.” (The “MC” denoted her initials.)
Qualifying as a Junior Doctor in 1952, Mary’s first post was as Senior House Officer in the Radiotherapy Department at ‘the London’ (later the Royal London Hospital), a post usually only open to male staff, where she worked with male patients with venereal disease. Her appointment was a reflection of shortages in the profession due to the war. Working in the clinic too was Dr. Duncan Catterall whom she went on to marry (he later became an eminent venereologist). Mary’s medical career prior to making the film followed a familiar path of gaining experience leading to job progression; she was appointed Junior Registrar and moved on to working with patients with tuberculosis at the London under Dr. Lloyd Rusby, Consultant, and Dr. Colin Ogilvie, Senior Registrar, the latter being the leading expert on respiratory physiology in the UK. Ogilvie had developed new tests in which he analyzed breathing and respiration into discrete functions as well as introducing new drug treatments such as streptomycin. Through Ogilvie, Catterall met Geoffrey Boden with whom she went on to work. He generously granted Mary a platform to talk about their research on tissue damage caused by radiation which was under-researched at the time. However, Boden, a heavy smoker, died suddenly in 1957 and her enthusiasm for this research waned without his mentorship so, in 1959, she willingly relocated to Leeds when Duncan took up the post of Consultant in Charge of the Genito-Urinary Medicine Department at Leeds General Infirmary. Throughout Mary’s career, the shifts in clinical discipline and geography were due to following her husband from London to Leeds and then back again. While this seems distinctly unmodern today, she did reflect upon how it was natural at the time.
In 1960, after a year in Leeds, Mary secured the post of Senior Registrar in Respiratory Medicine at the hospital. Catterall brought her clinical experience of caring for patients with severe lung conditions to her new position. One of the things she observed in her new role was the deficiency in the delivery of oxygen to those patients with severe breathing problems. Catterall’s clinical knowledge was a catalyst for her drive to improve the health and well-being of the patients in her care—an approach evident throughout her career. Taking a novel approach, Mary developed and patented an improved oxygen delivery mask, the New “MC” Oxygen Mask for “Effective Oxygen Therapy.” (The “MC” denoted her initials.)
No one initially wanted to invest in her design, although her archives reveal that the organization British Oxygen was interested. This is an example of how her gender appeared to mitigate against being taken seriously. However, displaying tenacity, she had taken the precaution of securing a temporary patent and, then, before the patent expired and her design was at risk of plagiarism or theft, the Royal Army Medical Corps placed a large order. The lightweight design made the mask well-suited to being used in combat situations. In fact, the masks were used on the battlefields in the Falklands War in 1982, which, according to Catterall, resulted in no British soldiers dying of their injuries largely due to the importance of oxygenating the blood, vital to life.
A mask developed and patented by Dr. Mary Catterall (Dr. Mary Catterall PP/CAT, Courtesy Wellcome Collection.).
“where there’s muck there’s brass”
What does require some critical thought is whether, as Catterall suggests, in some small way, It Takes Your Breath Away contributed to or perhaps even began the transformation of Leeds into, in her own words, the “smart and sparkling” place it is now. Unfortunately, the film’s distribution history in Leeds is unknown. The British Medical Association acquired a print when it was entered in their annual film competition in 1964. The films in the library were available to members, but the distribution history of these prints has been lost. Mary would have known about the Medical Officer of Health reports produced by Leeds City as her husband, Duncan Catterall, reported on venereal disease in the area in his capacity as Physician in Charge at Leeds General Infirmary. Additionally, the Chief Public Health Inspector for Leeds City, Mr. J. Goodfellow, was elected on numerous occasions to the Chair of the National Society for Clean Air (successor to the National Coal Abatement Society), and this organization is acknowledged in the final credits of the film. So perhaps it would be more accurate to say that the film contributed to the urgent debate around the medical effects of pollution by a compassionate clinician who found herself on the frontline of what looked like a medical emergency. As Catterall recalled:
I attacked the urban pollution, particularly of Leeds with my usual frontal assault—I talked graphically and frequently to doctors, city councilors, trade unions, to administrators, anyone who would listen, and to those who would have preferred not to. Reading now, some of the articles I wrote and lectures I gave, I am surprised that we had as many friends as in fact we did.
Catterall’s campaigning activity was picked up by the press: “Equating Muck with Brass Condemned, Plea for Clean Chimneys” (Guardian October 1963); “The Air We Breathe in Leeds Is Dangerous Says Woman Doctor” (Yorkshire Evening Post) However, according to Mary, her mother-in-law told her that, it was “a pity to be so emphatic about it.” Her response was that, “I saw only the illness and pain it was causing!”
“many bronchitics sit at home too breathless to work”
Class, as indicated in the commentary to the film, was also a factor in the level of occupational and ambient exposure to environmental pollution. Official social classifications of British citizens by occupation and industry had been in place since the mid-1800s; Social Class Five (V) or unskilled occupations mentioned in the film, generally lived in urban polluted locations, whereas Social Class One (I) or professional occupations lived in the countryside or outskirts of cities with access to green spaces. These generalizations of the probable health effects of geography can be backed up with historical scientific data as recordings had been taken about the effect of air pollution on plants in and around Leeds.
Stills from It Takes Your Breath Away; Left, Man’s daily requirements (with air top). Right; the black lung (far right) from a townsman, the lighter-colored lungs (middle) from the countryman
National Library of Medicine #101771068
The film demonstrates how on a microscopic level tissue damage is also evident. In total, the environmental load from particulates on a city dweller is exceptionally high due to exposure to a cocktail of poisons. The film’s commentary mentions that pollution was implicated in 30,000 deaths annually in the UK due to a myriad of lung conditions—this is out of a net population of just under 54 million people. The scale of mortality is stark compared to that currently of COVID-19 in the UK. There is growing anger in the scientific community about the mounting evidence base relating to the outcomes of people recovering from COVID-19 and air pollution.
Switching pace, at seven minutes into the film, the narrative takes us into the clinic to discover the patient experience. Catterall’s knowledge as a clinician and as the medical adviser to the film gave the student filmmakers access to powerful patient testimonies. Catterall does not provide much in the way of detail to the production process, which she expresses here in brisk and somewhat clinical terms; “I met some film making students who wanted a theme. I wanted some filmmakers to make a film. We collaborated.” The patient case study is a frequent cinematic trope in medical films and has an important stylistic function as it underpins the injustices in the film. Catterall provides a moving insight into the lived reality of chronic medical conditions that negatively impact health and well-being. In the film, this takes the form of insight into the life of Jim Foulds, an ex-miner who at 58 years old cannot work and has a poor quality of life. Catterall admitted that for some bad cases, “iron lung” respirators were deployed to ease breathing at night—treatment usually associated with use in treatment for respiratory paralysis caused by polio and rapidly becoming redundant with the introduction of successful vaccines for the poliovirus. Catterall described how this treatment revealed a systemic flaw with air quality inside hospitals, “I had a patient with severe respiratory disease who had to go into an ‘iron lung,’ as respirators were then called, during the night. In the morning her neck and the cotton wool surrounding it were covered in soot from the air in the ward.” Hospitals were exempt from complying with the Clean Air Act. They were not compelled to modernize their energy use yet produced significant amounts of particulate-based air pollution.
“devastatingly dangerous to the lungs”
Back in London in 1965, Mary published her reports on respiratory-function tests in miners from her clinic in Leeds. It was a landmark study. Her findings were contrary to received orthodoxies and called into question the assessment of lung disease in miners. She was critical of the criteria to determine eligibility for compensation used by the Medical Research Council’s Pneumoconiosis Research Unit, based in Wales. She considered mining to be “devastatingly dangerous to the lungs.” Hitherto, only shadows on the lungs visible in x-rays granted eligibility for statutory compensation, which was critical in providing financial support for men of working age, many of whom had families to support. Catterall identified other physiological markers relating to lung function applicable across the patients referred to her, thereby finessing the effects down to an unprecedentedly discrete scale (in the film, she demonstrates an instrument for such identification at about seven minutes in). Her role as clinician was therefore to provide relief to her patients (if possible) but also to prove that their exposure was industrial and inadvertent.
There were other researchers working in this field, such as an MRC Unit working on Air Pollution, established in 1952 after the “Great Smog” but the source of the statistics quoted in the film was probably from The National Society for Clean Air. Statistics have bedeviled the environmental policy and lobbying sectors; measurements are clearly important, but their attendant interpretation has been controversial. This Unit demonstrated a direct relationship between levels of smoke, Sulphur dioxide, and chronic bronchitis, producing a series of studies that had been influential in underpinning the Clean Air Act.
A “Sore Point”?
What did Mary do next? After Catterall followed her husband back to London, she took up the position of Senior Registrar in Radiation Oncology, Middlesex Hospital. Later, she became a consultant in charge of the Fast Neutron Clinic, Hammersmith Hospital, until 1987. Neutron therapy was an experimental cancer treatment; neutrons were delivered in a high energy beam, causing a different biological effect to radiotherapy. The MRC-funded research into regressing, hard-to-treat tumors was not without controversy due to its cost; the press lambasted it as poor value in light of the limited test data. An editorial column on medicine in The Times, ‘Sore Point’ by Dr. Thomas Stuttaford, cited the British Medical Journal’s assessment of the project as “a dangerous white elephant”. This was because the Conservative Prime Minister of the time, Margaret Thatcher, had green-lit the project without consultation with the wider scientific and medical communities. The project is another example of Catterall working in a contentious area of medicine (here radiotherapy) and demonstrating her humanity by going against the orthodoxies at the time in the interests of her patients. From the clinic, Catterall wrote movingly about the significant impact of treating people living with these cancers and how the treatment gave them back their dignity by prolonging their lives in meaningful ways even though her clinic only received the most hopeless cases. The treatment allowed people to live the life they wanted, rather than the one that they thought they had been dealt, after a terminal cancer diagnosis.
The narrative of cities as unhealthy places to live in is all too familiar: yet cities are where, for various economic, financial, and social reasons, many of us are compelled to live. As climate change and environmental breakdown caused by human activity pose increasing threats to human health worldwide, planetary health is even more important because our health depends on the state of our planet, which is affected by our actions. How, therefore, can we make our cities good places to live? The film analyzed in this essay, a lesson from history, is illustrative of how social activism in the medical community, when professional and personal interests work in unison, can drive change in making our cities healthier places to live.
Angela Saward has been working with audiovisual archives for many years, researching, licensing, and managing the curatorial lifecycle of audio, film, and video. Currently, she is Research Development Specialist (Moving Image and Sound), Wellcome Collection, London, working with Wellcome’s unique and distinctive collections across many formats, supporting colleagues and cross-cultural partners, with a special emphasis on the audiovisual. She serves on the Steering Group for London’s Screen Archives and is an active member of FOCAL and AMIA. She has a business master’s MA MTA and a first degree in English Literature.
Angela has collaborated with NLM staff for many years, presenting joint talks on NLM and Wellcome films that share thematic, stylistic, and other elements. Past topics include screening the body, medical travelogues, environmental foci, and hidden collections.
Bryant, Gerard. “Guilty Chimneys.” BFI Player. Accessed December 31, 2020. https://player.bfi.org.uk/free/film/watch-guilty-chimneys-1954-online.
Carrington, Damian. “Tiny Air Pollution Rise Linked to 11% More Covid-19 Deaths – Study.” The Guardian. Guardian News and Media, November 4, 2020. https://www.theguardian.com/environment/2020/nov/04/tiny-air-pollution-rise-linked-to-11-more-covid-19-deaths-study?CMP=share_btn_link.
Catterall, Mary. “Better for Seeing You”: Reflections of a Doctor, Sculptor and Encourager. London: Mary Catterall, 2012.
“Clean Air Act 1956.” Wikipedia. Wikimedia Foundation, December 12, 2020. https://en.wikipedia.org/wiki/Clean_Air_Act_1956.
Clean Air: Supplement to the Leeds Journal, September 1956: a Survey of the Clean Air Act, 1956, with Some Indications of How Its Requirements May Be Met. Leeds: Leeds Incorporated Chamber of Commerce, 1956.
Corton, Christine L. London Fog: The Biography. Cambridge, MA: The Belknap Press of Harvard University Press, 2018.
“The History of Leeds – Cotton, Wool, Flax, Linen and the Industrial Revolution.” Aireborough Civic Society. Accessed December 31, 2020. http://www.aireboroughcivicsociety.org.uk/history/the-history-of-leeds-cotton-wool-flax-linen-and-the-industrial-revolution.
“Independent Engineering and Energy Consultants.” Nifes. Accessed December 31, 2020. http://www.nifes.co.uk/
Jones, Emma M. M. “Air Pollution Research in Britain C.1955-C.2000: the Transcript of a Witness Seminar Held by the History of Modern Biomedicine Research Group, Queen Mary University of London, on 19 May 2015 / Edited by EM Jones, C Overy and EM Tansey.” Museum. London, 2016. https://wellcomecollection.org/works/tp6arpuu.
Marsh, Arnold. Smoke: the Problem of Coal and the Atmosphere. London: Faber and Faber, 1947.
Pathé, British. “Air Pollution.” The world’s finest news and entertainment video film archive. Accessed December 31, 2020. https://www.britishpathe.com/video/air-pollution/query/AirPollution.
“Radio 4 – Last Word.” BBC. BBC. Accessed December 31, 2020. http://www.bbc.co.uk/radio4/news/lastword_27mar2009.shtml.
Rose, David. Issue brief. Edited by Nigel Gilbert. Official Social Classifications in the UK. Guildford, UK, 1995.
“Take Your Breath Away: Meaning in the Cambridge Learner’s Dictionary.” Cambridge Dictionary. Accessed December 31, 2020. https://dictionary.cambridge.org/dictionary/learner-english/take-your-breath-away.
Taylor, John. “Smoke Menace.” BFI Player. Accessed December 31, 2020. https://player.bfi.org.uk/free/film/watch-the-smoke-menace-1937-online.
Thorsheim, Peter. INVENTING POLLUTION: Coal, Smoke, and Culture in Britain since 1800. 1st ed. Series in Ecology and History. S.l.: Ohio University Press, 2006.
Wu, X., Nethery, R. C., Sabath, M. B., Braun, D. and Dominici, F., 2020. “Air pollution and COVID-19 mortality in the United States: Strengths and limitations of an ecological regression analysis.” Science advances, 6(45), p.eabd4049.
 The film was already held at Wellcome due to an accession from the British Medical Association in 2006, when the organization donated their film collection there.
 Catterall was aware that the film was in the collection and this could have been a contributory factor for the donation of her archives (she died in 2015). The writer spoke to Mary Catterall briefly prior to the donation; the conversation was an acknowledgement that Wellcome Collection held her film.
 Martin went on to become a BBC Radio 4 newsreader and announcer. Martin had trained as a medical photographer, which perhaps is how his path crossed with Catterall’s; http://www.bbc.co.uk/radio4/news/lastword_27mar2009.shtml
 Coal smoke contains particles of Sulphur dioxide, which combined with rainwater creates acid rain.
 The Smoke Menace (British Commercial Gas Association, 1937) depicts the growth of the “dirt” trades such as window cleaning in Westminster, London [00:03:55]; a structural engineer inspects a historic building and explains the costs of the damage [00:04:31] https://player.bfi.org.uk/free/film/watch-the-smoke-menace-1937-online. In Guilty Chimneys (Gas Council, 1954) https://player.bfi.org.uk/free/film/watch-guilty-chimneys-1954-online [commentary at 00:04:49]; a cleaned building stands out “like a bride at a funeral.” The film also acknowledges the relationship between “spirit and health” as well as showing photographic evidence of stonework damaged by pollution [00:07:15]. Environmental pollution damage to buildings is described as “social vandalism towards an irreplaceable heritage.” [00:11:00]
 Mary Catterall, “Better for seeing you”: reflections of a doctor, sculptor and encourager, self-published, 2012? p. 73.
 Mary Catterall, ibid., pp. 69-70
 See Christine L. Corton, London Fog, The Biography (Cambridge, Mass.: Belknap Press, 2015).
 Temperature is a key contemporaneous factor leading to so-called adverse temperature-inversion pollution events. The London smog was caused by a period of low temperature with very little wind that cloaked the city in thick smog for four days. https://en.wikipedia.org/wiki/Clean_Air_Act_1956
 Medical Officer of Health, Leeds City. Report 1961, Wellcome Collection. p. 269/312 digitized pages [unnumbered photograph, inserted between physical pps. 236-7]. [Report 1961] / Medical Officer of Health, Leeds City. | Wellcome Collection
 Both Britain’s nuclear and hydro-electric power industries were in their infancy; the first nuclear power plant at Sellafield was operational from 1956 and the first hydro-electric dam in Ffestiniog, north-west Wales, in 1963.
 Medical Officer of Health, Leeds City. Report 1959, Wellcome Collection. p. 274/284 digitized pages [unnumbered photograph, inserted between physical pps. 222-3]. [Report 1959] / Medical Officer of Health, Leeds City. | Wellcome Collection
 Peter Thorsheim, Inventing Pollution: Coal, Smoke, and Culture in Britain since 1800 (Ohio University Press, 2006) pp. 121-2; The regulation of air pollution in Leeds was described as “lackadaisical” in the early years of the twentieth century due to the lack of trained personnel to carry out tests and the influence of the manufacturing lobby.
 Medical Officer of Health, Leeds City. Report 1958, Wellcome Collection. 235/288 digitized pages [unnumbered map, inserted between physical pps. 204-5]. [Report 1958] / Medical Officer of Health, Leeds City. | Wellcome Collection
 Medical Officer of Health, Leeds City. Report 1965, Wellcome Collection. 237/284 digitized pages [unnumbered diagram, inserted between physical pps. 210-1]. [Report 1965] / Medical Officer of Health, Leeds City. | Wellcome Collection
 Medical Officer of Health, Leeds City. Report 1964, Wellcome Collection. 233/286 digitized images [unnumbered photograph, inserted between physical pps. 208-9]. [Report 1964] / Medical Officer of Health, Leeds City. | Wellcome Collection
 Leeds Incorporated Chamber of Commerce, 1956. Clean air: supplement to the Leeds Journal, September, 1956: a survey of the Clean Air Act, 1956, with some indications of how its requirements may be met. https://wellcomecollection.org/works/wsn5jdbg
 Archives from the organization are held at Wellcome Collection, SA/EPU.
 Geoffrey Boden’s last published paper from 1955 was on “The Patient and the Röntgen” in The British Journal of Radiology; https://www.birpublications.org/doi/abs/10.1259/0007-1285-28-336-677
 Mary Catterall, ibid., p. 69; “I suppose nowadays, I would not have accepted a complete change of career, and I would have worked in London, while Duncan was in Leeds and we would have met at weekends in, say Grantham. But even in “now” time, I think I would have found that a silly arrangement of our lives.”
 The phrase “where there’s muck, there’s brass” (also used as a chapter heading by Catterall in her autobiography) harks back to the fortunes made in the Industrial Revolution by coal, textile, and woolen merchants from the city (perhaps referring to their fancy brass buttons), and the awe in with which citizens viewed this wealth.
 Mary Catterall, ibid., p. 73
 Arnold Marsh, Smoke: The Problem of Coal and the Atmosphere (London, Faber & Faber, 1947), p. 81. Trees three miles north of Leeds had 158 mgm./sq. metre of soot deposits and were evergreen and flowered. But in industrial Leeds, there were 1620 mgm soot deposits, and the leaves fell in November. Another sorry tale relates to experimental cabbages; in Westwood Lane eight out of nine survived the winter, but in the more urban districts of Park Square and Hunslet they were all dead by the end of November and October respectively.
 UK COVID-19 related deaths are 75,024 from a population of 66.65 Million, January 2021; 0.11% of population versus 0.59% from bronchitis-related deaths in 1952.
 https://www.theguardian.com/environment/2020/nov/04/tiny-air-pollution-rise-linked-to-11-more-covid-19-deaths-study?CMP=share_btn_link The article links to a peer reviewed study by X. Wu, R. C. Nethery, M. B. Sabath, D. Braun, and F. Dominici, “Air Pollution and COVID-19 Mortality in the United States: Strengths and Limitations of an Ecological Regression Analysis,” Science Advances, 6, no. 45 (2020): p.eabd4049. https://projects.iq.harvard.edu/covid-pm
 Mary Catterall, ibid., p.72-3
 Ibid., p.70
 Mary Catterall and I. Hunter, “Results of Respiratory-Function Tests in Miners” in The Lancet, ISSN: 0140-6736, Vol: 285, Issue: 7377, Page: 154-158 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(65)91108-6/fulltext The work of the unit is treated with some levity in this cinemagazine news item from British Pathé, 1968, https://www.britishpathe.com/video/air-pollution/query/Air+Pollution with individuals from the unit inhaling carbon monoxide and cigarette smoke for experimental purposes. Further information about the operation of the unit is explained in Air pollution research in Britain c.1955-c.2000 : the transcript of a Witness Seminar held by the History of Modern Biomedicine Research Group, Queen Mary University of London, on 19 May 2015 / edited by EM Jones, C Overy and EM Tansey. https://wellcomecollection.org/works/tp6arpuu
 Thomas Stuttaford, (1989) ‘Sore point’, Times, 05 Jan, 9, available: https://0-link-gale-com.catalogue.wellcomelibrary.org/apps/doc/IF0500000422/TTDA?u=wellcome&sid=TTDA&xid=4b223e30 [accessed 22 Dec 2020].