Participants were interviewed as part of a larger multi-sited ethnographic fieldwork study, ‘Organs as a Gateway to Europe’ [16], that ran from 2021 until 2026 across the Euro-Mediterranean border. This study focused on migrants in The Netherlands, Bulgaria, Türkiye, Italy and Greece who sold, or contemplated selling, their kidneys. The Ethics Review Committee of the Erasmus School of Law of the Erasmus University Rotterdam provided ethics approval [ETH2122-006], and the study received funding from the Dutch Research Council (VI.Veni/201R.010, 2021-2026).

Countries were selected based on their geographic position along the Eastern Mediterranean migration route. This constitutes a key migration corridor into Europe [17] and has not been previously studied in the context of migrant kidney sales. We did not conduct research in countries across the Central Mediterranean route, because this region has previously been explored by Columb [2, 3, 8, 9]. In addition, due to time and funding restrictions, it was not feasible for the research team to include more field sites.

In each of the countries, medical professionals were purposively approached who worked in the field of migration or in the field of transplantation, first, because knowledge about their experiences with migrants’ kidney sales is scarce. Second, we anticipated that due to the nature of their profession, they would be able to provide relevant insights into our research aims.

In lieu of the explorative, qualitative nature of our study, participants were approached using a combination of opportunistic and convenience sampling techniques. Initially, transplant professionals (TPs) who were known to the authors were emailed and invited for an interview. These included transplant professionals known through professional affiliations and networks such as Erasmus MC, the European Society for Organ Transplantation (ESOT), the European Platform on Ethical, Legal and Psychosocial aspects of Transplantation (ELPAT) and the Dutch Transplantation Society. These professionals further nominated prospective respondents, whom they believed could share experience, knowledge, and perspectives about migrants’ kidney sales.

The majority of health professionals working in migration (MMPs) were not previously known to the authors. Through volunteer ethnography in the various field sites, connections were formed with professionals working for non-governmental organizations who provided care and support for migrants. These participants were approached via face-to-face introductions from interlocutors, independently visiting their offices, or via email.

Our sampling strategy resulted in 45 interviews, 28 with TPs and 17 with MMPs. TPs included transplant surgeons, nephrologists, nurse practitioners, transplant coordinators, social workers, and psychologists. MMPs included general practitioners, a urologist, a gynecologist, a pulmonologist, and nurses working or volunteering for health clinics in asylum centers, mobile health clinics, medical humanitarian agencies, and hospitals. The participant characteristics are presented in Table 1.

ZR conducted the majority of the interviews while FA conducted a minority between March 2023 and February 2026. Data saturation was reached among both groups, with themes regularly re-emerging, before all interviews were completed. All participants verbally consented to the interviews, 23 of which were audio-recorded and transcribed. Given the sensitivity of the research topic, the other 22 medical professionals did not want to be recorded. In these cases, detailed notes were taken instead and included in the coding and analysis. Recorded interviews were semi-structured following a topic list pertaining to professional background, local medical/transplantation context, migrant patients/donors, migrant kidney selling, and organ trade. Non-recorded interviews followed the same topic list but were discussed with an open-ended interview approach. The detailed topic list is included as Supplementary Appendix 1.

Apart from two online interviews with MMPs, all interviews were conducted face-to-face. Interviews took place at transplant conference venues, inside respondents’ offices, or in public areas selected by the respondents. The interviews lasted between 30–60 min and were performed in English, French, or Dutch. ¹

To ensure data protection and participant safety, the research team adopted specific security measures. All respondents were informed that their names would be pseudonymized. Interviews were recorded using double authenticator work phones and audio-records were immediately uploaded to a protected digital environment of Erasmus MC and thereafter, immediately deleted from the phone recording devices. Transcripts were pseudonymized and fieldnotes were anonymized to further enhance participant confidentiality. An encrypted pseudonym key file was stored separately from the dataset.

The transcripts were imported into NVivo software [Nvivo 15.4 (c) Version 3.0] for coding qualitative data. ZR inductively coded all transcripts into thematic concepts. Two coding structures (one for each group), across all countries, were generated. For each group, similar codes were grouped into themes. Interpretations of themes, conceptual relationships, and similarities and differences between and among the two groups were discussed during multiple, team-based analytic discussions to ensure that the full breadth of data was captured. The themes were organized around the relevant domains of “experience,” “knowledge,” and “response.” “Experience” was defined as “hearing testimonies from migrants, seeing suspicious scars on migrant bodies, or receiving inquiries from migrants, and for transplant professional, having a (potential) donor who was an asylum seekers, refugee, or undocumented migrant.” “Knowledge” included “being aware of migrant kidney selling, the speculations TP and MMPs had about migrant patients/donors as well as the intersection of migration and transplantation, stories they heard about migrant kidney selling, and the limitations of their knowledge on migrant kidney selling.” “Response” was divided into “attitudes” and “reactions.” Attitudes were understood as their behaviour or opinion towards migrant kidney selling. “Reactions” included their “actions, or lack thereof, in understanding or reporting migrant kidney selling.”

The multidisciplinary background of the research team (i.e., anthropology, sociology, criminology and nephrology) ensured that various interpretations and perspectives were taken into account, encouraged reflexive considerations and reduced risk of discipline-specific biases. Reliability of findings was further enhanced by triangulating data from different types of respondents from different geographic locations and by involving multiple researchers in data collection, analysis and reporting.

Of all respondents, mostly MMPs reported direct experiences with migrants who had sold a kidney. In contrast, only very few TPs had experiences with this issue. One nephrologist and one transplant surgeon reported direct encounters with migrants who had sold a kidney. They described observing nephrectomy scars and, upon inquiry, receiving either an evasive response (interpreted by the professional as indirectly suggestive of organ trade), or an explicit admission that the kidney had been sold. Importantly, their reported experiences were not based on their work within transplant settings, but on their involvement as medical volunteers in the migration field. TPs who exclusively work in transplant settings report more speculative accounts. For example, one TP shared an instance where a medical visa was arranged for a donor who traveled from abroad to donate to a recipient. However, the donor never showed up for the scheduled surgery. Another TP shared receiving anonymous kidney offers which he assumed to be from migrants, because those offering were of African origin.

Overall, TPs reported very limited interactions with migrants as donors, more commonly treating migrants as renal patients. Most TPs described their experiences with organ trade through assumptions relating to transplant tourism, i.e., patients traveling abroad for dubious kidney transplantations.

Contrastingly, five MMPs spoke of seeing nephrectomy scars and, similar to the two TPs, shared receiving defensive responses upon their enquiries, or confirmation that they had sold their kidney. The timing of these encounters varied: one participant experienced it a year ago, another 3 years ago, two during the 2015 ‘migration crisis’, and one MMP did not provide an answer. Two others shared experiences of migrants consulting them for information about transplantation procedures, revealing they were considering selling their kidney. One MMP experienced this 5 years ago and the other did not recall years but described it as “the man it was a while ago, but the woman it is recent.”

Except for the two TPs who worked as volunteers in the migration field and the transplant surgeon who received anonymous kidney offers assumingly from migrants, all other TPs were unaware of migrant kidney selling. Instead, TPs reported knowledge about organ trade generally based on cases of transplant tourism, rumors, media reports, and conference presentations. Their awareness thus largely stems from second-hand stories.

Among MMPs, awareness of migrant kidney selling was primarily limited to those with direct experiences, and those who had learned about such cases through colleagues. However, some MMPs were aware of the limitations of their consultations which constrained their awareness of this issue. They explained that unless a migrant travels through a tuberculosis-risk region or requests a physical examination, their bodies are rarely examined, leaving potential scars unnoticed. ‘'If the resident [asylum seeker] does not say anything, we’ll never find out. Or you really have to be lucky that the same person comes to us with stomach pain. Then you look at them and ask, ‘What’s that scar?’ But the chance is small, because during the check you’re not facing their back. And that cut is over there, on the flank. Yeah, it will not always be noticeable to me.” [MMP, The Netherlands, 2025]

MMPs added that without prior awareness of migrant kidney selling, nephrectomy scars do not necessarily arouse curiosity, given the multitude of scars routinely observed on migrant bodies. Possible identification of signs of migrant kidney selling thus largely relies on the proactiveness of MMPs and the willingness and courage of migrants to share their experiences. MMPs noted however, that migrants will be unlikely to share their stories, especially if they are under the unjustified belief that revealing a punishable activity may hinder their asylum application.

When asked how they (would) respond(ed) to migrants who sold, or wanted to sell a kidney, most MMPs and TPs expressed uncertainty on when, where and how to report such cases. None of the instances shared by MMPs and TPs were reported to authorities. Both TPs and MMPs stated that they (would) treat(ed) the migrant and that they (would) discuss(ed) the case with their colleagues.

Given their limited experience and knowledge of migrants’ kidney sales, most TPs spoke about organ trade in more general terms. They explained that they find it challenging to make organ trade suspicions concrete. Most of their experience concern speculations and most of their knowledge stems from second-hand accounts. Some TPs shared that once a donor is approved on paper, few critical questions follow, despite having suspicions.

Others expressed a need for guidance and protection in handling suspicions of organ trade:

Most TPs who recounted organ trade suspicions, including those with direct experience, quickly added ''having forgotten the details.” Most had shared the case within their multidisciplinary teams. Others explained being cautious about sharing their thoughts about organ trade suspicions with patients and colleagues, fearing potential reputational harm. Some TPs kept cases to themselves, regarding it as patient confidentiality. A TP mentioned:

While few TPs accepted that organ trade could occur in Europe, including in their own transplant facilities, most others assumed that organ trade could not occur in their facilities, due to thorough donor screening, ethics committees, state oversight, and the small, interconnected transplant community. Yet, again, they acknowledged that their lack of knowledge and awareness may unwittingly narrow their perception and attentiveness to organ trade.