Christa Lehmann poisoned three people in Worms, a city on the Rhine in what was then West Germany, between 1952 and 1954. Her husband died in September 1952 and her father-in-law in October 1953, and doctors certified both deaths as natural. In February 1954 a liqueur praline she had prepared with the insecticide E 605 was eaten by her friend Annie Hamann, a war widow, instead of by Annie's mother, for whom Lehmann later said it had been meant. Annie Hamann died soon after eating it, and so did the family dog.
The case is remembered in Germany for two reasons. It is regarded as the first proven use of E 605, the trade name for parathion, as a murder weapon, and the forensic toxicologist who found it, Kurt Wagner of Mainz, became widely known for his work on it. It also spread knowledge of the poison. Newspapers called it the "Wormser Gift," the Worms poison, and suicides and murders with E 605 rose sharply soon afterward. Historians of pharmacy now describe the case as one that made visible a much wider problem with a highly toxic chemical sold freely for gardens and farms.
Lehmann confessed, was tried in September 1954 and was sentenced to life imprisonment. She served about 23 years, was released by clemency, and lived afterward under another name. In the 1970s she gave long recorded interviews to the journalist Ernst Klee, whose 1977 book about her remains the main source on her own account of her life.
Much of what is published about this case goes back to two sources: the 1954 trial and its press coverage, and Ernst Klee's 1977 book, built on his conversations with Lehmann in prison. The court record itself is held in the state archive at Speyer. Modern accounts differ on several details, among them her husband's first name and the month of his death.
Christa Ambros was born in Worms in the early 1920s. The Argentine newspaper Crónica gives the year as 1922. Her childhood was hard by every account. Her mother had a mental illness and lived in the psychiatric hospital at Alzey, in Rhenish Hesse. Her father, by the account in the pharmacy trade journal Die PTA in der Apotheke in 2019, beat her; Crónica describes him as a drinker who left the family to itself. The pharmacy historian Bettina Wahrig of the Technical University of Braunschweig, summarizing Klee's book, places the family in the working class.
Wahrig's summary records that in the 1930s and 1940s the young woman changed jobs several times because a foreman pursued her. Accounts agree that she was in trouble with the law early: the 2019 trade-journal article says she committed offenses young without saying what they were, and Dirk C. Gibson's chapter on her in his book Serial Killers Around the World lists her early crimes as one of its subjects.
During the war she married Karl Franz Lehmann, a tiler. The trade-journal article says she was 21 at the wedding; Crónica gives the year as 1944 and her age as 22. According to Wahrig's reading of Klee, she married under pressure from her father, and the groom was the son of a well-off friend of his. The couple shared a household with his father in Worms.
The marriage went badly from the start. The 2019 article reports that her husband spent their wedding night with a buffet waitress. He drank heavily and suffered from a stomach illness, and quarrels and physical fights between Christa, her husband and his father were a constant part of the household. Black-market dealing was uncovered in the family business. Wahrig's summary describes a young housewife who was financially dependent on her husband and her father-in-law while the family business struggled.
The couple had children, and Wahrig records that the first died of malnutrition in the early years after the war. After her third child, by her own account to Klee, she could no longer bear sexual relations with her husband, who was often drunk, and she asked how more children were to be fed. Wahrig sums up her situation in four words: no contraception, no consent.
Wahrig's account, drawn from Klee, says that in early 1952 Lehmann hoped a hospital stay for her husband would give her some respite. The poison she used came from inside the family. Her father, a hobby gardener, had given her E 605 and warned her that it was very poisonous.
E 605 was an insecticide made by Bayer from 1948. The chemist Gerhard Schrader had developed it during work on phosphoric acid esters that grew out of research on chemical weapons, the same line of work that produced the nerve agents tabun and sarin. It was sold as a dust and as a liquid in ampoules for mixing into sprays, and it was widely used against insect pests on farms and in vegetable and fruit gardens. It works by blocking an enzyme the nervous system needs, and a large dose leads to convulsions and death from respiratory failure. In the early 1950s the pure substance was nearly tasteless and odorless.
Lehmann put the poison in her husband's breakfast milk. Karl Franz Lehmann died in September 1952 after severe cramps. The emergency doctor recorded a perforated stomach ulcer, and since the dead man was known to drink heavily and to have stomach trouble, no one questioned it. Wahrig's text, following Klee, places this first killing in February; the 2019 trade-journal article and Crónica put the death in September 1952. The trade-journal article also calls him "Fritz" at this point, while naming him Karl Franz Lehmann earlier in the same piece.
After her husband's death Lehmann stayed in the household of her father-in-law, Valentin Lehmann. The trade-journal article describes her as a cheerful widow who openly brought a series of lovers to the shared flat, and says her father-in-law objected strongly; the two clashed again and again. Wahrig's reading of Klee puts this period differently: Lehmann went to cafes and bars in Worms and the surrounding area with her friend and began new relationships, and Klee treated this as a woman exercising her own choices, not as the moral failing the 1954 press made of it.
In October 1953 Valentin Lehmann fell from his bicycle and died on a trip into town. A doctor called by passers-by recorded heart failure. Nothing pointed to his daughter-in-law. She later said she had put E 605 in his yogurt.
By early 1954 Lehmann's closest friend was Annie Hamann, a war widow who lived with her mother, Eva Ruh, her brother, Walter, and her daughter, who was 9, according to Crónica. Annie's mother disliked the friendship. Accounts differ on how far her suspicion went: Wahrig, following Klee, says the friend's mother had grown suspicious of Lehmann, and the 2019 trade-journal article says simply that Eva Ruh was deeply unhappy about the friendship.
Little else about Annie Hamann's life has come down. She had lost her husband in the war and was raising a young daughter in her mother's home. Her age and occupation do not appear in the accounts of the case.
In February 1954 Lehmann brought chocolate pralines filled with liqueur to the Hamann household. According to her own later account, as reported in the trade journal, she had opened the chocolate coating of one praline with a heated knitting needle, let the cognac filling run out and replaced it with E 605. The pralines were shared out during the visit. Eva Ruh refused hers, even though Lehmann pressed her to eat it, and put it away in the refrigerator.
The next day Annie Hamann took a bite of the praline her mother had put aside and spat most of it out. The family dog, a white Spitz, ate what she spat out. Annie collapsed with cramps and died within a short time; the emergency doctor who was called could do nothing for her. The dog died just as quickly.
The dog's death was what made the doctor suspicious, according to the 2019 trade-journal account. A young woman's sudden death might have passed as natural, as two deaths in the Lehmann family already had, but a dog dying the same way at the same time pointed to something both had swallowed. Annie Hamann's body was sent to the Institute of Forensic Medicine in Mainz.
The institute was headed by Kurt Wagner, a physician and chemist born in Gera in 1905 who had studied chemistry in Dresden, Bonn and Jena and medicine in Leipzig. He had led forensic toxicology in Berlin in the 1930s and had been professor of forensic medicine and criminalistics at Mainz since 1946. The University of Mainz's professors' catalog records that he became widely known for his expert opinion in the Worms praline murder. The same catalog records that he had been a member of the SA from 1933 and of the Nazi Party from 1937 until 1945.
In 1954 there was no routine screening test that would have found E 605 in a body. Crónica notes that the effects of the poison resembled those of cyanide. According to the trade-journal account, Wagner acted on a hunch and tested Annie Hamann's blood specifically for parathion, and the test was positive. Crónica describes the analysis of her stomach contents. Either way, the result showed that the praline Eva Ruh had put aside had contained a lethal dose of the insecticide.
Suspicion fell on the woman who had brought the pralines. Lehmann was arrested and questioned. Crónica says she held out for some weeks before confessing; other accounts give dates that have not been confirmed. She told investigators that the praline had been meant for Eva Ruh, not for Annie, and she went on to admit that she had also poisoned her husband and her father-in-law.
The bodies of Karl Franz Lehmann and Valentin Lehmann were exhumed. Both showed traces of E 605. The two deaths that had been certified as a perforated ulcer and as heart failure were now established as poisonings.
Wahrig's account of Klee's book adds a point about the third killing. In her talks with Klee more than two decades later, Lehmann came to see that she had intended that killing; the "confession" in the book's title, Wahrig explains, refers to that admission.
The case dominated West German headlines for months in 1954. Klee later called it the case of the century, and Wahrig quotes that phrase. The trial opened on September 20, 1954, according to Crónica. The indictment and verdict are reproduced in Klee's book, and Wahrig notes that, in Klee's presentation, they show continuities with the Nazi past. The court files are held today by the Landesarchiv Speyer, under the signature J 76 Nr. 364 to 368, according to a record in the Worms city archive's catalog.
Lehmann was convicted and sentenced to life imprisonment. The published reports give the sentence without setting out the verdict count by count.
Lehmann spent the following years in prison and was at some point moved to the women's prison in Frankfurt, according to Crónica. She was repeatedly suicidal. The 2019 trade-journal article says she tried several times to take her own life and that every attempt failed. Wahrig, from Klee's book, adds that she harmed herself again and again, that she once poisoned herself with lead from a lead pipe, and that she was placed on a psychiatric ward after she began to hallucinate.
In the late 1960s Ernst Klee, a journalist trained in social education, began researching conditions in West German prisons. A prison director put him in touch with Lehmann. He recorded conversations with her over several days, and the result was the book Christa Lehmann: Das Geständnis der Giftmörderin (The confession of the poisoner), published in Frankfurt by Krüger in 1977. Wahrig describes it as a book that gives Lehmann a great deal of room to tell her own story while Klee supplies the context, and as an argument for a different treatment of prisoners serving life and for broad prison reform. Klee concluded, in a line Wahrig quotes, that nothing remained of the pleasure-seeking woman of the 1954 headlines.
Lehmann applied for clemency many times without success. Wahrig records that it was finally granted, partly because of the reckoning with her own guilt that her talks with Klee had helped bring about. The 2019 trade-journal article and Crónica both say she was released after 23 years in prison, which places her release in about 1977. She then lived for many years under a different name, inconspicuously.
The 2019 trade-journal article said she was still alive, under another identity, and nearly 100 years old. Crónica wrote in May 2025 that it was not known whether she was still living. No report of her death has appeared, but she lived under another name after her release, and whether she is alive has not been confirmed.
The Worms trial made the poison famous. The 2019 trade-journal article says the press coverage of the "Wormser Gift" was sensational and that within a very short time there was a sharp increase in suicides and murders using E 605. A 2011 interview with the Cologne pharmacy historian Erika Eikermann, in the same journal, says the case led directly to further poisonings and suicides with the substance, and describes a case two years after the Worms trial in which a hospital pharmacist was accused of sending mocha eclairs laced with E 605 to her lover's family; a child died, and the pharmacist was acquitted for lack of evidence. A 2010 Ärzte Zeitung article, drawing on Eikermann's work, calls E 605 a fashionable poison for suicides in the years until its sale was sharply restricted by law.
Historians have since put the murders in a wider frame. Anette Marquardt, writing for the Braunschweig pharmacy-history collection, notes that the great majority of E 605 poisonings were suicides or accidents, even though the substance is mostly associated with murder. Wahrig writes that the Lehmann case made visible a series of suicides and accidental poisonings that had begun before it and grew afterward, and that current estimates put the number of suicides with organophosphate pesticides worldwide in the hundreds of thousands. A 2026 study of homicidal poisonings in Germany by Ohm and Seifert, in Naunyn-Schmiedeberg's Archives of Pharmacology, lists Lehmann as the first murderer with E 605 in its case series, says the case made many people aware of the substance, and records the last E 605 murder in its data in 1982.
The first changes targeted the properties that had made the Worms killings possible. According to the 2019 trade-journal article, the liquid on sale was dyed a yellowish brown and given a sharp, garlic-like smell. The legal historian Martin Rath, writing in Legal Tribune Online in 2015, also notes the added garlic odor and observes that strongly seasoned food could still hide it. A 2019 Schwäbische Zeitung article says the substance had to be dyed blue; the color named differs between the two sources.
Pharmacies had long been required to record poison sales. Marquardt's study of one small-town pharmacy's sales ledger in Lower Saxony, held in the Braunschweig collection, found 201 sales of parathion between 1958 and 1978, each recorded with the buyer's name and address, the product, the quantity and the date. Pharmacists had to be satisfied that the product would be used properly; otherwise they could sell it only against a police permit. The trade-journal article says that until 2002 the pesticide could still be bought on showing an identity card. Trade in and use of E 605 have been banned in Europe since January 2002.
Klee's book is not the only study of the case. Gibson's English-language book on serial murder around the world includes a chapter on her. In 2011 a group of students at the Gauss-Gymnasium in Worms wrote a 57-page study of the case in the context of the Adenauer era for the German President's history competition, and gave it to the Worms city archive. The archive also notes a Wormser Zeitung article by Klaus Kipper, published on July 3, 2004, for the 50th anniversary of the poisonings. The 2014 report on Eikermann's lecture in the Pharmazeutische Zeitung calls the 1954 case the first poisoning trial with E 605, known as the "Pralinenmord."
Several points in published accounts remain unsettled:
Her husband's first name. Most accounts call him Karl Franz Lehmann; the 2019 trade-journal article calls him "Fritz" when describing his death.
The month of the first killing. Wahrig, summarizing Klee, places it in February 1952; the trade-journal article and Crónica give September 1952.
Who supplied the poison. Wahrig, from Klee, says her father, a hobby gardener, gave it to her. The other reports do not say where it came from.
A 2019 Schwäbische Zeitung article says her mother-in-law advised her to put something in the food of the husband who was tormenting her. Other reports do not repeat the story.
Her motive in the third poisoning. She said the praline was meant for Eva Ruh. Wahrig reports that, in her talks with Klee, she came to accept that she had intended that killing.
Her exact date of birth, the exact dates of the deaths, of her arrest and of her confession, the number of life terms imposed and the exact date of her release have not been confirmed.
Early 1920s: Christa Ambros is born in Worms (1922 per Crónica).
About 1944: She marries Karl Franz Lehmann, a tiler, and moves in with his parents in Worms.
1948: Bayer begins selling the insecticide E 605 (parathion).
1952: Karl Franz Lehmann dies after drinking poisoned milk (September per most accounts; February per Wahrig's summary of Klee). The death is certified as a perforated ulcer.
October 1953: Valentin Lehmann dies after falling from his bicycle; certified as heart failure.
February 1954: Lehmann brings liqueur pralines to the household of Annie Hamann and Eva Ruh. The next day Annie Hamann eats the praline her mother put aside, and she and the family dog die.
1954: Kurt Wagner's institute in Mainz finds parathion; Lehmann is arrested and, after questioning, confesses to all three poisonings.
1954: Both men are exhumed; E 605 is found.
September 20, 1954: Her trial opens. She is convicted and sentenced to life imprisonment.
About 1956: A hospital pharmacist is accused in another E 605 poisoning and acquitted.
Prison years: suicide attempts and self-harm; transfer to the women's prison in Frankfurt; recorded conversations with Ernst Klee.
1977: Ernst Klee publishes Christa Lehmann: Das Geständnis der Giftmörderin. She is released by clemency after about 23 years.
January 2002: Trade in and use of E 605 are banned in Europe.
2019: A trade-journal article reports her alive under another identity, nearly 100.
May 2025: Crónica reports that it is not known whether she is still alive.