Toilets Under the Microscope: Global Study Maps 77 Years of Sanitation Research and Finds Gender Gaps

It is one of the most universal of human experiences, and yet one of the least examined corners of academic research: the toilet. A new open-access study published in Discover Social Science and Health has taken on the unglamorous but vital task of mapping nearly eight decades of scholarship on toilets and sanitation, and its conclusions carry an uncomfortable punch. Despite the toilet’s central role in public health, dignity, and human rights, the researchers found that research on gender-inclusive toilets, particularly all-gender and gender-neutral facilities, remains strikingly understudied. Most empirical work concentrates on health outcomes and women’s access, while the needs of men, gender minorities, and LGBTQ+ communities receive only a fraction of scholarly attention.

The research team, led by Priyakumaran Moorthy of Vellore Institute of Technology together with Sudha Mohan, Sravan Kumar Miryala, and S. Meenakshi, assembled an unusually comprehensive dataset. Drawing on the Scopus database, one of the largest scholarly repositories in the world with more than 84 million records, they retrieved every document published between January 1946 and December 2023 that matched the keywords “toilet,” “gender-neutral toilet,” and “all-gender toilet.” After refinement, the corpus contained 1,614 documents, of which 1,522 were research articles and 92 were reviews. Data were extracted on April 30, 2024, and the search was deliberately confined to the subject areas of social sciences, arts and humanities, and multidisciplinary research, with studies referring only to open defecation excluded to keep the focus on toilet facilities themselves.

Methodologically, the study is a two-stage affair that combines bibliometric analysis with content analysis, a pairing that allows the authors to measure both the quantity and the substance of the field. On the quantitative side, the team used RStudio with the Biblioshiny interface for performance and citation analysis, VOSviewer for co-word, co-citation, and bibliographic coupling networks, and Publish and Perish software for ranking metrics such as the h-index and i-index. On the qualitative side, Atlas.ti performed automatic coding of document content, while NVivo 14 was used to build a coding scheme and visualize themes. Keywords were first scrutinized through the Open Knowledge Maps platform to ensure the search terms captured the conceptual landscape of the field. The authors note that any field with more than 500 publications “deserves a bibliometric analysis,” and toilet research, with its 1,614 documents, comfortably clears that bar.

The publication trend tells a story of a field that has recently accelerated. Annual growth in output runs at approximately 6.9 percent, and the number of documents published between 2010 and 2023 increased noticeably compared with earlier decades. Open-access publishing has doubled in recent years, reflecting a broader shift in scholarly communication. Yet the citation picture is more complicated: even as publication rates climbed, a decline in citations was observed, a pattern the authors attribute in part to the recency of much of the output. Collaboration, by contrast, is a defining feature of the field. The collaboration index per paper stood at 14.71, and roughly 90 percent of the most influential texts were collaborative contributions, with only about 10 percent sole-authored. Scholars from women’s studies, sociology, social work, and tourism all contribute, underscoring the multidisciplinary character of toilet research.

Who leads the field? The co-citation analysis identified Aunger R., Koottatep T., Sommer M., Angelakis A.N., Curtis V., Dwumfour-Asare B., Ghisi E., Gunther I., Luiselli J.K., and Mosler H-J. as the most influential authors. Among the most cited documents are studies of hygiene behavior in Burkina Faso, household cleaning intentions in the slums of Kampala, Uganda, a randomized controlled trial of a behavior-change intervention on peri-urban sanitation quality in Lusaka, Zambia, and research on menstruation-supportive water, sanitation, and hygiene facilities in refugee camps in Cox’s Bazar, Bangladesh. The most productive countries were the United States, the United Kingdom, India, China, Australia, Ethiopia, Japan, South Africa, Bangladesh, and the Netherlands, while leading institutional contributors included Wollo University, Hokkaido University, Columbia University, the University of KwaZulu-Natal, University College London, and the London School of Hygiene and Tropical Medicine. Top publishing venues ranged from PLOS ONE and Scientific Reports to the Journal of Water, Sanitation, and Hygiene for Development and Social Science and Medicine.

The keyword analysis offers perhaps the most revealing window into the field’s intellectual structure. Of 4,058 author keywords, only 108, or 5.66 percent, appeared five or more times, and these clustered into eleven thematic groups. The single most frequent keyword was “sanitation,” with 113 occurrences and a total link strength of 157, followed by “toilets” and “toilet.” Cluster themes spanned ecological sanitation, wastewater reuse, and climate change on one end, and disability, accessibility, and inclusion on another. A third cluster centered on poverty, slums, informal settlements, and urban sanitation, while a fourth captured public health, human rights, COVID-19, and the needs of older adults. A fifth cluster brought together gender, discrimination, transgender issues, design, and space, with the keyword “gender” appearing 27 times and “transgender” 13 times. Bibliographic coupling of documents, filtered to those with at least 40 citations, produced eight clusters and surfaced foundational works including the 2007 paper “Potty Parity in Perspective: Gender and Family Issues in Planning and Designing Public Restrooms” and a 2016 study linking transgender adults’ access to college bathrooms and housing with suicidality.

The content analysis sharpened these findings into five parent themes: age and toilet accessibility, gender and toilet, social qualities, water, and toilet education and training. Within these themes, the terms “human,” “female,” “male,” “sanitation,” and “water supply” dominated the coding, with frequencies reaching into the hundreds. The three-field plots linking countries, authors, and keywords revealed dense clusters indicating that the bulk of toilet research concentrates on adjacent issues rather than on gender identity and inclusivity themselves. The authors conclude that the future focus should turn toward gender-neutral and all-gender toilet concepts, embedded in the social and cultural contexts of the people who use them. Notably, the analysis also flagged an under-discussed dimension: sanitation during natural disasters. Floods, storms, and conflicts pose severe challenges to sanitation management, and the study argues that non-gendered toilet designs would be more economical, inclusive, safe, and accessible in such crises.

The historical framing adds depth to the statistical picture. The paper traces the toilet from the communal pits of ancient Rome, where latrines functioned as remarkable social spaces, through Sir John Harington’s invention of the modern flush toilet in the sixteenth century, Alexander Cummings’ nineteenth-century patent for tank-based flushing, the popularization of dual-flush systems in the 1980s, and the rise of sensor-activated technology in the twentieth century. Modern Japanese toilet technology, the authors note, has significantly shaped today’s smart toilets. Against this technological arc stands a sobering global reality: around 3.6 billion people still struggle to receive safely managed sanitation services, 2.4 billion lack access to proper sanitation, and open-pit latrines persist in impoverished communities due to insufficient public funding. The United Nations’ Sustainable Development Goal 6, with its target of adequate and equitable sanitation for all by 2030, has yielded significant results in Africa, China’s “Toilet Revolution,” and India’s Swachh Bharat Mission, but the study argues that gender-specific toilet patterns alone will not fulfill SDG 6 when the needs of gender minorities and economically marginalized people remain unaccommodated.

The study is candid about its limits. The search was restricted to English-language, peer-reviewed journal articles and reviews in the Scopus database, grey literature was excluded, and country names were removed during content analysis to keep the coding focused. Publication year filters and subject-area restrictions further narrowed the corpus. Even so, the implications are clear and, the authors hope, actionable. They identify four priority gaps for future research: hygiene and dignity in toilet access, all-gender and gender-neutral toilet design, gender-inclusive toilet policies, and cultural perspectives on toilet use. With roughly 70 percent of the world’s population projected to live in cities, and with toilet access framed as a fundamental right for children, the elderly, people with disabilities, and gender minorities alike, the message of this sweeping bibliometric map is that the humble toilet deserves far more scholarly attention, and that inclusive sanitation policy is not a peripheral concern but a central test of whether the sanitation goals of the coming decade will be met for everyone.

Subject of Research: Bibliometric and content analysis of global toilet research and gender-inclusive sanitation

Article Title: Bibliometric and content analysis of global toilet research and inclusive sanitation

Article References: Moorthy, P., Mohan, S., Miryala, S. K., & Meenakshi, S. (2026). Bibliometric and content analysis of global toilet research and inclusive sanitation. Discover Social Science and Health, 6(1), Article 92. https://doi.org/10.1007/s44155-026-00427-1

Image Credits: AI Generated

DOI: 10.1007/s44155-026-00427-1

Keywords: sanitation, toilets, bibliometrics, gender-neutral toilets, public health, SDG 6, hygiene, LGBTQ+ inclusivity, Scopus, content analysis, WASH, human rights