Accidental Exposure to Poisonous Houseplants

An analysis of cases reported to poison information centers

The great popularity of houseplants is based on their decorative and esthetic appeal as well as their health benefits (release of oxygen, binding of carbon dioxide and air pollutants, purifying the indoor climate, reducing mold growth, mental wellbeing).

While some of the lists of houseplants (1) published worldwide highlight the hazard and poisonous ingredients of these plants, they do not present data on actual cases of exposure. Relevant monographs (2) also pay less attention to houseplants and their components than to garden plants.

Methods

Human exposure data from the Poison Control Center of Charité—Universtätsmedizin Berlin (2016–2020), the Joint Poison Information Center of the states of Mecklenburg-Western Pomerania, Saxony, Saxony-Anhalt, and Thuringia in Erfurt (2010–2022), the Poison Center Freiburg (2008–2018), the Austrian Poison Information Center in Vienna (2016–2021), and the Tox Info Suisse in Zurich (2008–2018) were analyzed retrospectively. Reported cases were anonymized and evaluated.

The houseplants were identified by their owners, garden centers, pharmacies, or specially trained staff at the involved poison information centers based on their botanical names. We used the botanical names according to Zander (3).

Human exposure data from the poison information centers were only included in the analysis, if the following inclusion criteria were met: confirmed, accidental dermal, ocular and/or oral exposure to plant parts and/or plant sap. Any exposure was considered confirmed if it was plausibly observed or if plant parts were noted/identified in the mouth, feces, on the skin, or in the eyes. All age groups were included, but only cases of poisoning by a single plant species. All symptomatic exposures were assessed for causality and included only if causality was deemed at least likely (4).

Non-human exposure and exposure to garden plants were excluded (4). Reports of intentional poisoning (suicide attempts), poisoning from plant preparations as well as puncture wounds from plant parts, aspiration of plant parts, and allergic reactions were also not included.

Exposure of children up to 13 years of age and adolescents/adults aged 14 years and over were analyzed separately. The degree of severity was classified based on the Poisoning Severity Score (5).

The study was approved by the Ethics Committee of Charité Berlin (EA2/116/24) and registered retrospectively in the German Register of Clinical Trials (DRKS) (see registration DRKS00036222 for further details).

Results

A total of 18 621 confirmed accidental exposures involving 215 houseplant genera/species were evaluated with regard to severity and symptoms (age groups: children (n = 17 636; 94.7%); adults (n = 985; 5.3%). The majority of cases (15 678; 84.2%) were asymptomatic; mild symptoms were reported in 2880 cases (15.5%). Moderate symptoms (63 cases; 0.3%) were caused by 19 different houseplant genera/species. No cases with severe symptoms were reported.

In children, the most common exposure route was ingestion of plant parts (97.5%), followed by dermal absorption (2.9%). In adults, by contrast, the percentage of ingestion was lower (63.6%), while dermal exposure was more common (30.1%). Children were most frequently exposed to leaves, flowers, and plant sap, adults to leaves and plant sap.

Of the total of 17 636 recorded cases of exposure in children, 15 181 (86.1%) were asymptomatic. In 37 cases (0.2%), the severity of the symptoms was classified as moderate. Of the 985 adult cases, 49.5% developed symptoms; in 26 cases (2.6%), these were of moderate severity.

The ten houseplant genera/species most commonly associated with exposure are summarized in Table 1. These plant species accounted for 64.2% (n = 11 971) of all cases of exposure.

Table 1

Houseplant genera/species that most commonly led to confirmed accidental exposures (by frequency)

The 19 houseplants listed in Table 2 caused moderate symptoms following exposure.

Table 2

Houseplant genera/species having caused moderate poisoning

Discussion

The aim of this study was to identify houseplants in Germany, Austria and Switzerland capable of causing moderate to severe symptoms after accidental exposure.

Overall, exposure to houseplants was significantly less common among adults compared to children (985 and 17 636 exposures, respectively). When accidental poisoning occurs in adults, dermal exposure is more common compared to children (30% and 3%, respectively). Ocular exposure plays a relevant role in adults, accounting for almost 10% of cases, while it is rare in children (0.2%).

In children, oral exposure dominates with 97.5% due to the fact that young children in particular put objects they can reach into their mouths to explore their physical properties. The higher proportion of cases of dermal and ocular exposure among adults compared to children may be attributable to plant care activities.

In the presented cohort, the high number of asymptomatic patients (15 678; 84.2%) is noteworthy, similar to exposure to garden plants (4). However, symptoms are reported twice as often after accidental exposure to houseplants compared to garden plants (16% and 7%, respectively).

Only ten of the 215 houseplants account for the majority of all cases of exposure. Furthermore, nine of these ten houseplants were identified as the cause of moderate symptoms. In contrast to garden and wild plants (4), there are no reports of severe symptoms.

After exposure to houseplants, most children remained asymptomatic; cases of mild to moderate symptoms were rare. In contrast, cases with mild or moderate symptoms were observed more frequently in adults.

The data from the poison information centers is valuable for identifying houseplants that can cause moderate symptoms after accidental exposure.

Jörg Pietsch, Daniela Acquarone, Angelika Holzer, Tara Arif, Joan Fuchs, Michael Deters, Kathrin Begemann, Maren Hermanns-Clausen

Institut für Rechtsmedizin, Abt. Toxikologische Chemie, Technische Universität Dresden, Dresden, Germany (Pietsch) [e-mail]

Vergiftungs-Informations-Zentrale, Klinik für Allgemeine Kinder- und Jugendmedizin, Kinder- und Jugendklinik, Universitätsklinikum Freiburg, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany (Hermanns-Clausen)

Giftnotruf der Charité Universitätsmedizin Berlin, Berlin, Germany (Acquarone)

Vergiftungsinformationszentrale Österreich, Gesundheit Österreich GmbH, Vienna, Austria (Arif, Holzer)

Tox Info Suisse; Assoziiertes Institut der Universität Zürich, Zurich, Switzerland (Fuchs)

Gemeinsames Giftinformationszentrum der Länder Mecklenburg-Vorpommern, Sachsen, Sachsen-Anhalt und Thüringen (GGIZ), Erfurt, Germany (Deters)

Bundesinstitut für Risikobewertung (BfR), Berlin, Germany (Begemann)

Conflict of interest statement
The authors declare no conflict of interest.

Manuscript received on 31 March 2025; revised version accepted on 29 July 2025

Translated from the original German by Ralf Thoene, M.D.

Cite this as:
Pietsch J, Acquarone D, Holzer A, Arif T, Fuchs J, Deters M, Begemann K, Hermanns-Clausen M: Accidental exposure to poisonous houseplants: An analysis of cases reported to poison information centers. Dtsch Arztebl Int 2025; 122: 676–7. DOI: 10.3238/arztebl.m2025.0143

References

1. The encyclopedia of house plants. http://gflora.com/index.php?cmd=genus (last accessed on 27 May 2025).

2. Teuscher E, Lindequist U: Natural poisons and venoms. Vol. 1–3: Plant toxins. Berlin, Boston: Verlag Walter de Gruyter 2023–2025

3. Erhardt W, Götz E, Bödeker N, Seybold S (eds.): Zander. ­Handwörterbuch der Pflanzennamen. Stuttgart: Verlag Eugen Ulmer 2014.

4. Hermanns-Clausen M, Koch I, Pietsch J, Andresen-Streichert H, ­Begemann K: Akzidentelle Vergiftungen mit Gartenpflanzen und Pflanzen in der freien Natur: Daten aus zwei deutschen Giftinformationszentren Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2019, 62, 73–83

5. Persson H, Sjöberg GK, Haines JA, Pronczuk de Garbino J: Poisoning severity score. Grade of acute poisoning. J Toxicol-Clin Toxic 1998, 36: 205–13