Scheele's green was ideal for printing wallpapers, especially those with floral motifs. Wallpaper production rose steadily throughout the 1800s: in the UK it reached 1 million rolls a year in 1830 and 30 million rolls by 1870. When tests were then carried out it was found that four out of five wallpapers contained arsenic. Arsenic in wallpaper had a habit of diffusing into the air of a room and thereby affecting its occupants. This had been suspected as long ago as 1815, but the mechanism by which it occurred was not correctly deduced until the 1890s, and what exactly was being released was only solved in 1932.
In 1815 there was a report in a Berlin newspaper to the effect that arsenic pigments in wallpapers were dangerous and this had been written by Leopold Gmelin (1788-1853) who was to become one of the best-known chemists of his day. He was perhaps too far ahead of his time, but people in Germany had already begun to suspect that arsenic wallpapers could poison the indoor atmosphere. Gmelin had noticed that rooms which had been covered with wallpaper printed with Scheele's green gave off a mouse-like odour when the paper was slightly damp. He suspected the vapour was an arsenic compound, and he said that it was unhealthy to spend too much time in such a room. He even went so far as to advocate stripping off all such paper and banning Scheele's green. No one took any notice. Had they done so, and taken action, then much illness and not a few deaths would have been prevented in the decades ahead.
In articles published in the Dublin Hospital Gazette in 1861, Dr W. Frazer of the Carmichael School of Medicine reported that every sample of wallpaper that he had been asked to test contained arsenic, and not just in trace amounts but at levels he thought might be injurious to those who came in contact with them. Frazer imagined that the threat came from breathing the dust from such papers, especially flock wallpapers, but he realized that this was not the only way in which arsenic could get into the air of a room. Frazer postulated that arsine gas (AsH3) or even cacodyl* might in some way be emitted from wallpapers that were damp, and he added that the wallpaper paste might be partly to blame. Frazer noted that often one layer of wallpaper would be pasted over another and that the lower layers often became ripe for 'putrefactive change' and that it was a gaseous arsenic emanation from such walls that was responsible for the peculiar smell that was often noticed in such rooms. He was right about it being due to arsenic vapour, he was right to speculate that the wallpaper paste had a part to play, and he was nearly right when he speculated that it might be cacodyl.
In 1864 there were reports in the press of children actually dying as a result of the vapours given off by mouldy green wallpaper, and the medical journal Lancet warned of the dangers of arsenic pigments. A typical wallpaper would contain around 700 mg/m2 so that an average-sized living room would hold around 30000 mg of arsenic, in theory enough to kill more than a hundred people. Most of this arsenic would remain on the walls of the room unless they became damp. The nature of the aerial poison was unknown at the time but this did not stop concerned individuals launching campaigns against the use of arsenic-based pigments even though these flew in the face of most medical opinion which regarded arsenic as a potent medicine and good for treating all kinds of afflictions of the human body. In addition the general public had discovered that when arsenic-based papers were used on bedroom walls there was a noticeable disappearance of bed bugs, a major benefit that led to increased sales. Moreover, arsenic cigarettes were popular and reputed to cure nervous complaints, and arsenic-based cosmetics were supposedly good for the complexion. How could the tiny amount that was emitted by wallpapers be dangerous? It seemed illogical to claim otherwise and so Scheele's green and emerald greens continued to be used.
In the last quarter of the 1800s the most famous wallpaper designer of all was William Morris (1834-96) who was one of the leading lights of the Arts and Crafts Movement, which brought a new style to interior design. He was also a tireless campaigner for left-wing causes, even producing his own socialist newspaper Commonweal. Not that his concern for a better life for all
* This is a methyl derivative of arsenic and the word cacodyl comes from the Greek word kakodes meaning stinking. It consists of two arsenic atoms bonded together, each with two methyl groups attached: (CH3)2As-As(CH3)2.
caused him to question the source of his wealth and its unhealthy origin in the west of England. That region had been mined since the Bronze Age because its rocks were a rich source of copper, tin, and lead. Another mineral that was to be found there was arsenopyrite, iron arsenic sulphide (FeAsS), but this was generally seen as a nuisance because if arsenic contaminated copper and tin it made them very brittle. Arsenic was removed by roasting the ores in furnaces whence it was emitted as arsenic trioxide which tended to collect in the flues. This was removed periodically and thrown on to the heaps of mine waste.
Morris's father was a successful broker in the City of London and he lived in a large mansion near Epping Forest, north-east of the capital. He speculated in all kinds of ventures but nothing was as successful as his investment in the Devonshire Great Consolidated Mining Company which struck lucky on 4 November 1844 when it discovered one of the greatest copper lodes ever found in Britain. The Morris family held 304 of the 1024 shares issued by the company and they were to see these rise in value from £ 1 per share to £800 per share within a year and pay a first dividend of £71 a share. (The mine eventually paid out more than £1 million in dividends, equivalent to more than £100 million today.)
Morris's father died in 1847, shortly after one of his investments went spectacularly wrong, and the family had to move to a more modest home in Walthamstow. They retained most of their shares in the copper mine and Morris's widow gave 13 of these to each of her nine children thereby securing each of them a comfortable income of around £700 a year, equivalent to around £100000 today.* In 1853 Morris went to Oxford University with the intention of training for the ministry, but it was there that he was drawn into the circle of left-wing intellectuals and artists that became the Arts and Crafts Movement.
William Morris's first wallpaper design was called The Trellis and consisted of a climbing rose on a wooden trellis. There was a lot of green in the pattern and that green was copper arsenite. Morris was to become a strong advocate of traditional pigments and dyes, and used them whenever he could. He was also aware that the buying public wanted vibrant colours and these could only be produced with synthetic dyes like Scheele's green.
* During his lifetime William Morris earned almost £9000 from this investment, equivalent to £1.5 million now.
Indeed at the time The Trellis appeared on the market the production of Scheele's green in England was in excess of 500 tonnes/year. Morris's wallpapers became very popular and this was doubly profitable for him because he was to become a major shareholder in the largest arsenic-producing mine in the world. Maybe he closed his mind to those who claimed that such wallpapers could poison the air of the rooms in which they were hung. He was wrong to do so because they were right: it could.
In 1871 Morris joined the board of Devon Great Consols when it had been priced out of the market for copper by cheap imports, but the firm now realized that its mountains of waste could be processed to extract arsenic which became its main source of income. Up to then arsenic had been imported from Germany where the mines of Saxony produced it as a byproduct. Now Britain became the world's largest producer and user. Year by year arsenic production increased as they began to reprocess the slag for its arsenic, generally to local disapproval because of the pollution such work caused. West Country arsenic was of high quality and much in demand from glass and enamel manufacturers (a little arsenic would neutralize the iron which gave glass a green tint). Soon arsenic was being exported as more and more uses were found for it, for example in pesticides, and the price rose from £1 a ton to £20 by the mid-i870s. Production at the Devon Great Consols soared to 3500 tonnes/year in the 1890s but the company was ultimately to decline as its attempts to mine for other metals met with no success.*
Morris was on the board of the company for five years, but his other interests made heavier demands on his time. It would be nice to think he resigned because he was aware that arsenic was coming under increasing criticism for its deleterious effects on those who worked to produce it, those who lived in the vicinity of where it was produced, on the workers in industries which used it, and even on the general public who innocently bought the products of which it was part. Such was the concern about arsenic that the Factories and Workshop Act of i895 made it a legal requirement to notify the authorities of cases of arsenic poisoning, although the act was
* The Devon Great Consols mine had a revival in the next century when arsenic was needed for making war gases such as chlorovinyl dichlorarsine a blister gas more unpleasant than mustard gas. In World War II this was made in a tin works at South Crofty mine. This was the last working tin mine in the UK, finally closing down in March 1998.
mainly designed to deal with the industrial diseases arising from lead and phosphorus which were of particular concern.
While the new Act improved working conditions in some industries it did little to relieve those who worked for the arsenic manufacturers. The men whose job it was to scrape the arsenic-laden soot from the flues of the furnaces were particularly badly affected and the Government was eventually forced to set up an inquiry into conditions in the industry. Its report of 1901 acknowledged the terrible effects that exposure to arsenic was causing, yet it did not recommend measures to control the industry, mainly because the industry itself was now in rapid decline and indeed Devon Great Consols itself went out of business a year later. It had produced more than 70 000 tonnes of arsenic trioxide in the previous 30 years.
In the 1870s it became possible to use synthetic green dyes that were not based on arsenic and indeed wallpaper manufacturers, including those making papers for Morris, began to advertise that their products were free from arsenic, although privately Morris remained sceptical that wallpaper pigments were the cause of all the illness being blamed on them. The weight of scientific opinion was against him, however, and as the Victorian era drew to a close it was clearly established that wallpapers were capable of poisoning people by the gas they gave off.
Was this article helpful?