**Arsenic entered the waterways as a result of the artificial production of dyes. Illustration by Marco Heer.**

A poison to dye for

Around 1860, arsenic was widely known as a poison used in murder cases. Nevertheless, the authorities in Basel were initially oblivious to the potential dangers emanating from its use in dye production. The cantonal chemist alone recognised that the industrial use of the ‘King of Poisons’ could have unintended consequences for both people and the environment.

Claudia Aufdermauer

Claudia Aufdermauer is a freelance historian.

Benedicta Gschwind, daughter of the president of the court of Arlesheim in the canton of Basel-Landschaft died suddenly in March 1873 at the age of 23. She had been making red paper flowers in the morning, was complaining about stomach pains by noon and passed away a few days later. The doctor called to the scene was baffled: he suspected the red paper, which had a shimmery surface that left a trace on the hands when touched. A chemical scientist examined the craft material but gave it the all-clear: it was not the supposed cause of death. But why all the fuss? Why should anyone have believed that a piece of paper could have the power to kill someone?

The rise of the dye industry in Basel

Let’s go back 14 years. In 1859, Alexander Clavel, a Frenchman who had settled in Basel more than 20 years previously, expanded the dyeworks he owned in the hope of capitalising on a business trend that was revolutionising the textile industry at the time. It had recently become possible to produce dyes artificially. This involved aniline ‒ a waste product derived from coal tar ‒ and various chemicals. The dye formulas varied depending on the factory and chemist. It took Clavel several attempts before he succeeded in producing violet, red and blue tones.

The time and place were ideal for Clavel to establish himself as a dye manufacturer. He had very few competitors around the globe during this era and only one in Basel itself: Johann Jakob Müller-Pack. As the dyes had a short shelf life, the dyeworks’ proximity to the textile industry in Alsace and Basel’s own silk ribbon trade was a major advantage. Both raw materials and finished products could be transported by train ‒ Basel was already connected to the French railway network ‒ and via the Rhine. There was only one problem: the two dye factories were located right in the city centre.

**A chemist at the J. R. Geigy works in Basel, which produced synthetic dyes. Photograph taken around 1909.** Novartis Company Archives, N Publ MI 000.344000.344#018

It didn’t take long before people in the neighbourhood began complaining about the black smoke constantly being emitted from the dyeworks and the damage it was causing to their houses. They also claimed it was no longer possible to hang washing out to dry without it turning a shade of yellow. These complaints prompted Cantonal Chemist Friedrich Goppelsroeder to visit Clavel’s factory. He was concerned to see members of the workforce handling large quantities of arsenic acid in narrow dye kitchens – with no more protection than sponges soaked in vinegar covering their mouths and noses. The reason for his concern: as the name suggests, arsenic acid is derived from arsenic, which is obtained by roasting ores containing the mineral. It has been known since the Middle Ages as a poison used in murder. Its lack of odour and taste and its resemblance to table salt meant the poison could be ingested by the victim without being detected.

Goppelsroeder knew that mixing the elements arsenic and hydrogen could spontaneously give rise to an undesirable byproduct: the industrial poison arsine, which is highly toxic. So he was even more concerned to see workers cleaning the copper retorts used in the production process by boiling water in them and emptying the whole thing into a neighbouring pond. He did not believe that the arsenic-bearing waste would sink to the bottom as intended. Instead, he thought it would impregnate the grass and potentially poison the cattle grazing on the meadow. In any case, even the city’s drinking water could be in jeopardy.

The accuracy of Goppelsroeder’s suspicions became evident a short time later when he was called urgently to the home of a property owner. The man himself and his entire household, including his wife, his three daughters, his son, a maid and a gardener, had all been vomiting constantly since drinking some tea. They were running a fever and unable to sleep, and insisted that Goppelsroeder subject the drinking fountain attached to the property to chemical analysis. Goppelsroeder’s examinations showed the water to contain significant levels of arsenic and concluded that this must have come from the dyeworks next door owned by Johann Jakob Müller-Pack.

**The Rosental factory in Basel. When Johann Jakob Müller-Pack went bankrupt, the plant was taken over by Johann Rudolf Geigy. Photograph dating from 1921.** Novartis Company Archives, Geigy BB 6

An ever-present threat

The city’s inhabitants and authorities were stunned by this realisation, which ultimately spelt financial ruin for Johann Jakob Müller-Pack. The arsenic-bearing production waste from his dyeworks had poisoned the neighbouring pond, the ducks and fish in it, the pond floor, the groundwater, the municipal pumping station and a total of five wells that supplied the local population with drinking water. The matter was brought before the courts, with the Basel authorities keen to see the guilty man punished. But even more important was the question of how to prevent similar incidents from occurring again in the future.

The hazard analysis produced by the city authorities may have been detailed, but it ignored the impact such factory waste could have on the flora and fauna. The powers that be ordered dye manufacturers to evaporate the arsenic-containing liquid waste from their factories. Waste with a low arsenic content was to be discharged into the Rhine, while the solid residues were to be taken “out of the country” immediately to ensure they no longer found their way into the drinking water by way of the groundwater. Disposing of these residues posed a challenge even then: France and the Netherlands were already aware of the dangers of arsenic and had banned the practice of dumping barrels of arsenic-bearing residues into the sea.

“Dedicated to the green wreath and dress-mongers”: this illustration from British satirical magazine Punch presents the problem with synthetic dyes as a dance of death, 1862. — **“Dedicated to the green wreath and dress-mongers”: this illustration from British satirical magazine *Punch* presents the problem with synthetic dyes as a dance of death, 1862.** Heidelberg University Library

The public perception of arsenic experienced a major shift at this time. Whereas the Swiss press still carried reports around 1850 of Austrian farmers with the “curious” habit of ingesting small doses of arsenic, which they believed would give them “a healthy, fresh complexion and a certain degree of embonpoint”, newspaper articles began to take a more critical tone from the 1860s. Professors and chemists warned the public of the dangers associated with products coated with dyes containing arsenic. They were capable of releasing arsenic-bearing particles in the form of dust which, if breathed in, could poison the body. Special care was to be taken when consuming coloured marzipan figures, red wine, syrup and fruit juices, not to mention sweets wrapped in dyed paper. In 1874, some children in Graubünden were taken ill after visiting a fair. One even died. The post-mortem revealed traces of arsenic in the deceased youngster’s stomach. The child had eaten a figure made from dough, coloured red with a fuchsine coating, which the other children had also consumed.

Returning to the case of Benedicta Gschwind: the chemical scientist who examined the red paper following the young woman’s death was none other than the cantonal official Friedrich Goppelsroeder. Using the customary measurement techniques, he came to the conclusion that the paper did not contain any poisonous dyes such as arsenic or any other toxic metals. The paper had been printed using cochineal, a pigment derived from the insect of the same name: “Therefore, the dye cannot have caused the child’s death.” Confronted with the findings of the cantonal chemist’s examination, the doctor carried out a post-mortem. It revealed that Benedicta Gschwind had most likely died of peritonitis, an infection of the inner lining of the stomach, as indicated by the “exudations of pus”.

**Illustration from the German edition of Thomas Pridgin Teale’s educational work warning of the dangers of poisonous materials that surround us in everyday life.** From: Thomas Pridgin Teale: “Dangers to health: a pictorial guide to domestic sanitary defects”

Shifting the problems elsewhere

It soon became evident that, rather than solving the problems associated with the disposal of waste, the measures mandated by the Basel authorities merely shifted them elsewhere: from the ground to the air and water. Very soon, fishermen began complaining about dead fish that were “completely red inside ‒ to right under the scales”. They claimed that the poison had “forced the animals’ bright red innards out of their anuses.” People in the neighbourhood complained about the reek of the arsenic-infused fumes leaking from the dyeworks that caused coughing, headaches and nausea. These allegations aroused the Basel authorities’ suspicions and they discovered that the city’s dye producers were not evaporating their industrial wastewater or selling the solid residues abroad as claimed. Angered by the renewed hazard potential, the lies told by the dye manufacturers and the death of two employees at a Basel dyeworks, the city authorities banned the arsenic-based production of fuchsine at “all aniline works on local territory” from 1873.

From an economic point of view, the Basel authorities were finally able to take this step because alternative procedures for dye manufacturing had meantime become available. These new methods did not involve the use of arsenic: although slightly more expensive, nitrobenzene was to replace arsenic acids. On paper, therefore, Basel could be considered arsenic free from 1873, but in practice the ban was continually being flouted.

The reason for this lay beyond the canton’s borders. The factory owned by Ernst Karl Petersen in Schweizerhalle in the neighbouring canton of Basel-Landschaft continued to produce dyes containing arsenic. The fact that the plant discharged its wastewater into the Rhine, which then flowed on through Basel, gave the already sensitised Basel city authorities further cause for alarm. Petersen had promised that his factory was merely discharging small amounts of arsenic-bearing waste but what if, instead of releasing tiny amounts of it over time, the factory was discharging all the arsenic that had built up over several days in the space of an hour?

**The Rhine at Basel, seen from the terrace of the cathedral. Photographed circa 1862.** ETH Library Zurich

While the Basel authorities were busy petitioning the Swiss government in the matter of Petersen, one of the city’s fishmongers was also growing worried that the factories were driving away and killing the fish. He wrote to the Federal Council asking whether it was right and fair that these “gentlemen” were permitted to simply discharge their poisons into the river while the fishermen were bound to abide by certain rules set down in the Fisheries Act? He feared that if things continued in this manner, there would soon be no fish left to require protection by law.

Unlike the letter from the authorities, the “ire” vented by the fishmonger made an impact. The Federal Council instructed an expert – Basel-based pharmacist Casimir Nienhaus-Meinau – to conduct an investigation. He installed fish holding tanks at the Petersen factory and at all other works in the Basel region. As sensory perception cannot play a role in determining water pollution and measuring instruments had not yet been invented, at this point in the 19th century there was only one reliable method of verifying how damaging wastewater was: you placed a fish into the river in question and counted how long it took – minutes or hours – until it died. Most of the fish released by Nienhaus were recovered dead.

**Two children posing with a salmon near Augst, undated photograph. Salmon was a frequent catch in Basel right up to the 1920s.** StABL PA 6281 02.01-055

Nienhaus, who would enter the annals of history as a pioneer of water protection in Switzerland, nevertheless came to the conclusion that the arsenic-bearing industrial waste being dumped by the Petersen works was not that bad. As it was being discharged into the deep waters of the Rhine, where it was broken up, a freely moving fish would reach clean water in a single breath after passing through a layer of dye, thereby ensuring its survival.

Be that as it may, Nienhaus still believed that the production of fuchsine using arsenic should be banned – for aesthetic reasons. He had seen with his own eyes how the arsenic-bearing residues dumped in the middle of the river failed to disperse properly. And the Rhine continued to flow through Basel for another half hour in technicolour.

The records held in the official state archives for the canton of Basel-Landschaft and in the Swiss Federal Archives contain no indication that a ban on arsenic-based fuchsine production was ever discussed. It would appear that this particular production method remained in use at the Petersen factory right up until its founder’s death in 1908. A practice that would eventually prove very costly for the cantonal authorities: material contaminated with arsenic dating back to the time of Petersen is currently being remediated at the Rheinlehne site in Pratteln. The cost of these clean-up efforts, which have to be funded from the public purse as the polluter no longer exists and is therefore unable to pay, are estimated at CHF 180 million.

More of: 20th / 21st century Economy Research Politics

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