Country distribution of Indigenous food systems contamination research

Despite Indigenous populations inhabiting ~90 countries globally [18,19], publications about the contamination of Indigenous food systems are concentrated in a few countries. This likely provides an unbalanced picture of the relevance of this issue globally. The burden of disease from contamination is concentrated in low- and middle-income countries [2], contrasting with most studies included in this review being conducted in high-income countries (Table 2). This is concerning, as some of the greatest exposures to pollution occur outside high-income countries. For example, the bioaccumulation of mercury in Indigenous food systems is a major public health concern [46,70]. Artisanal gold mining is the largest source of mercury emissions, and China, Indonesia, and Colombia are the major documented polluters, with the latter having the highest per capita mercury emissions globally [71,72]. Although these three countries are home to large and diverse Indigenous Peoples, we only identified two studies conducted in Colombia and both among Amazon Indigenous Peoples, which is not illustrative of the vast diversity of Indigenous populations in the country [73].

Most countries with the largest proportion or total population of Indigenous Peoples, as defined by the International Work Group for Indigenous Affairs (IWGIA), are in Asia, Africa, and Oceania [64]. However, we only identified thirteen studies from those regions. This regional bias is partly linked to the global inequality of scientific research funding and production, but other factors are likely to play a role. For example, this discrepancy may be related to limitations in national government and researchers’ recognition of these populations, particularly in studies lacking community participation. Furthermore, there is no single definition of Indigenous Peoples, as there are often differing views about the characteristics that define Indigeneity [74,75]. This is further complicated by the ongoing impacts of colonization and the displacement of sovereignty, which continue to impact the social fabric of many Indigenous Peoples [76]. Moreover, depending on the context, communities may choose not to self-identify as Indigenous due to political factors or, in some cases, as a strategy for survival. Thus, the social and political struggle of Indigenous Peoples cannot be separated from the scientific practice of environmental health research and rigorous global assessment of contamination of Indigenous food systems.

However, the accumulated research experiences of Indigenous Peoples in some high-income countries can shed light on collaborative practices that could be implemented in comparable communities elsewhere [48,70]. Moreover, Indigenous Peoples around the globe face similar challenges and often experience an astounding gap in health outcomes compared to non-Indigenous counterparts in their countries [18,77]. For example, the structural racism within healthcare systems in Canada is persistent, and health professionals often lack a deep understanding of the historical and structural violence against Indigenous Peoples [78]. While there is a relatively large and increasing number of environmental health studies conducted in Canada among Indigenous Peoples, the elevated risk of these populations to toxic chemical exposure is persistent.

One factor that may hinder the translation of study results into improving Indigenous environmental health in Canada is that researchers are not adequately including the unique perspective of Indigenous Peoples in their studies or, alternatively, they are not fully communicating community-defined priorities in their publications [14,15]. To prevent cases in which researchers engage in meaningful collaborations with Indigenous Peoples but fail to report these partnerships in scientific publications, editorial policies should adapt to encourage explicit discussions on the role of community engagement in strengthening the rigour, effectiveness, and relevance of studies with a biomonitoring component.

Bridging Western and Indigenous knowledge through community engagement

Despite the challenges of bridging Indigenous and Western knowledge systems and building relationships with community members [14,79], there is mounting evidence of the benefits of these collaborative efforts on addressing environmental justice issues [49,51,54]. Although there is concern about the increasing negative effects of natural degradation on global food nutrition and security, Indigenous Peoples are known to be disproportionately affected by such adverse environmental changes [80–82]. Indigenous Peoples well-being is closely linked with local natural environments [12]. Thus, the deterioration of ecosystems may impact Indigenous Peoples’ health, culture and food systems in a shorter time scale than non-Indigenous populations living in areas with better access to alternative food sources. Moreover, this deeper connection with the natural environment is, above all, a source of unique knowledge that should increasingly become part of applied research in planetary health and other Western scientific fields. Indigenous Peoples’ traditions strongly value a collective awareness of the interconnectedness within nature and its inseparability from human well-being [9,51]. In addition, Indigenous traditional knowledge cannot be unpaired from the community and land [9]. Therefore, a meaningful articulation of Indigenous traditional knowledge and Western sciences requires capturing the particular context of the research.

In addition to the benefits of community engagement and articulating Indigenous Peoples frameworks that better explain the system-level complexity of toxic exposures [56,83,84], a horizontal dialogue to co-develop interventions and research projects could constitute an act towards reconciliation itself [85]. In this review, however, we observed a relatively low proportion of articles reporting including Indigenous knowledge in the study design, and only two studies using Indigenous research methods in addition to Western approaches. Our results are consistent with the findings of Chong and colleagues, who showed that researchers considered the meaningful inclusion of Indigenous knowledge as one of the most difficult challenges in the development of new community-based risk assessment approaches [14].

Indigenous scholars have highlighted that the assumed superiority of Euro-Western-centric knowledge in health research is resulting in an “epistemicide” (i.e., killing, silencing, annihilation, or devaluing of a knowledge system) that homogenizes knowledge and propagates value systems that ignore the interconnectedness of human well-being and nature [10]. Moreover, the meaningful and non-extractive inclusion of Indigenous knowledge and community-level context requires a focus on community engagement that is often lacking in research among Indigenous Peoples [10,14,15]. Despite the persistent challenges to articulate Indigenous and Western knowledge systems, fields like planetary health are progressively recognizing the key contributions of Indigenous knowledge to understanding the complex connection between humans and Nature [69]. As planetary health approaches are incrementally being included in higher education curricula, educators of health professionals and researchers should leverage this opportunity to promote innovative learning approaches that incorporate diverse knowledge systems [86]. This could strengthen the relevance and effectiveness of future risk assessments and studies of Indigenous food systems.

Community engagement strategies

We explored patterns in the proportion of community engagement strategies across the different methods used in the reviewed studies. The most common strategy was the participation of Indigenous members in conducting research activities, like data collection, followed by activities to receive feedback from the community. Combined, these two strategies presented the largest proportion across most study methods. Overall, 63% of the studies reported some level of community engagement. This figure contrasts with a previous review, which found that only 19% of Indigenous environmental health research conducted between 2000 and 2015 in the Circumpolar North discussed any engagement with the community [15]. This relatively large discrepancy is likely due to differences in the classification of community engagement, and that this review focused on a subset of Indigenous environmental health systems (i.e., food systems contamination). When only considering the three community engagement categories in our study that are comparable to Jones and colleagues’ classification (i.e., “Study requested by community”, “Results discussion in collaboration with the community”, and “Research methods designed in collaboration with the community”), we found that 33% of the studies reported one of these strategies. This percentage is closer to Jones and colleagues’ findings and consistent with the increasing trend reported for the 2000–2015 period [15].

In addition, we observed that among the 184 studies that collected human, food, or environmental samples, 34% did not mention a community engagement strategy. Although in some cases the lack of reporting could be caused by journals’ editorial constraints that limit authors’ ability to report existing community engagement activities, it may also be indicative of common concerning practices in environmental health research. The engagement of communities in the research process is particularly key to improving the sustainability and impact of studies that include a biomonitoring component [54]. Moreover, research among Indigenous Peoples should view community engagement as both a strategy to improve health and reduce hazardous exposures and a rights-based process that can strengthen communities beyond the study or intervention boundaries [57,87].

Approaches centred on the community exposed to pollution are particularly well-positioned to evaluate and manage the impact of contamination while promoting solutions that account for the complex contextual issues that threaten Indigenous Peoples’ well-being. This can be achieved by using participatory strategies and community-based projects where community members lead or are meaningfully involved at all levels of the research process. To inform environmental health policies, several participatory community-based biomonitoring studies of traditional food among Indigenous Peoples have indeed been conducted [70,88–90]. In addition to improving the quality of the studies, these community-based initiatives have a number of benefits, such as stimulating community interest in scientific studies, building local capacities, improving risk management and communication, and promoting self-reliance and decision-making at the local level [24,53].

Despite the potential benefits of community-based risk assessments, researchers and community members have reported persistent challenges in their implementation [14]. Partnerships between academia and communities could benefit from reflecting on better strategies to leverage solutions to contamination issues [91]. Previous studies have found that research directed by communities experiencing environmental injustice is more likely to result in action than research led by academic institutions [91]. Thus, institutions of higher education should use their power and prestige to amplify communities’ voices, while expanding opportunities to play a supportive, rather than leading, role in environmental health research [69,91].

Although not exclusive to qualitative methods, community engagement strategies were more commonly reported in studies that included them. This is likely related to the broad discussion in qualitative research on strategies to promote participation. Indeed, the validation of study results with the community is a criterion for assessing rigour in qualitative studies. Our results are consistent with Jones and colleagues’ conclusions on environment-related Indigenous health research in the Circumpolar North, reinforcing the authors’ call for further development of community engagement strategies in quantitative methods [15]. Hayward and colleagues discussed the dominance of qualitative methodologies in Indigenous research and the need for Indigenous quantitative methods to be expanded and strengthened [92]. They suggested a “strength-based” approach where the quantitative data analysis process acknowledges the positionality of the researchers and is consistent with community values and principles. This aligns with calls from Indigenous scholars for enforcing explicit positionality statements in research articles reporting on studies among Indigenous Peoples [10,93].

In addition, the inclusion of qualitative components and mixed methods should be considered in tandem with future quantitative research due to the importance of understanding contextual factors (e.g., food preferences and cultural values of traditional foods), including the reasons behind decisions that affect the environmental justice of Indigenous Peoples [94].

In this review, we found that ~17% of studies measuring contamination in human samples reported to have been requested by Indigenous Peoples. Moreover, a third of such studies did not mention any community engagement strategy. Due to the potential negative influence of human biomonitoring results on community members’ practices and perceptions, incorporating community engagement activities throughout the research process can strengthen locally relevant risk management and communication strategies [57]. Thus, we were expecting a relatively large proportion of community engagement strategies reported in the studies that collected human samples. However, this is not reflected in our data. Similar challenges can arise in food biomonitoring studies, as it can increase health concerns from consuming traditional foods [56]. The communication of biomonitoring studies results is a major challenge, including cases where low contamination levels were found, because it has the potential to shape community risk perception of exposure and unintentionally discourage beneficial practices, such as Indigenous food harvesting. Moreover, there is evidence that researchers consider risk communication the most challenging part of risk assessments among Indigenous and local populations [14]. However, most of these challenges can be addressed by developing equitable partnership with communities where researchers support risk evaluation but local and regional organizations lead risk management and communication, such as is the case in Nunavik [24].

Strengthening local and regional sovereignty over risk management and communication is key to reducing exposure to high-risk food due to contamination with toxic chemicals while balancing the health benefits of traditional food harvesting. National all-encompassing consumption advisories may be appropriate for populations with access to other healthy food sources, but promote unintended reduction of traditional foods. Such displacement of food preferences may heighten the risk of disease in Indigenous Peoples by increasing the prevalence of unhealthy diets and decreasing the benefits of traditional food harvesting [28,45]. Thus, to minimize the risk of toxic contamination and strengthen the benefits of traditional food systems in Indigenous Peoples, it is crucial to incorporate adequate and culturally sensitive risk assessment, management, and communication strategies [57,88,95].

Beyond documenting damage: Community use of study results and Indigenous authorship

In connection with the benefits mentioned earlier, community engagement can potentially expand the focus of environmental health scientific inquiry beyond solely documenting damage. Indigenous scholars have advocated suspending “damage-centred” research and reframing such projects as “desire-centred” inquiries [55]. This approach can produce analyses that challenge assumptions with regard to responsibilities, accountability and opportunities, and aid in dismantling the structures that position these communities as damaged [55]. Thus, the research process should not only respond to the requirements of non-Indigenous researchers but also factor in how the results are articulated and used in broader strategies to restore and promote traditional food systems as well as intergenerational knowledge transmission about traditional food harvesting, preparation, consumption and health and well-being properties.

In this review, we found that most studies that collected human, food, or environmental samples did not mention if the results were articulated with other present or future projects or interventions to control exposure, advocate for environmental justice, and/or improve environmental quality. When looking at studies that conducted qualitative research or articulated Indigenous and Western methods, the proportion of studies discussing how the community was using the results was relatively larger than for studies using quantitative methods exclusively. This is problematic because the lack of discussion across scientific fields and communities of practice may confine the dialogues on the inclusion of environmental justice and community-based participatory research to those already familiarized with the benefits and importance of these approaches.

Although these results may, in fact, represent a concerning pattern in quantitative research, the limited discussion of community use of study results in research articles is likely partly associated with different scientific writing practices across research paradigms. Journals that publish qualitative research may expect and encourage researchers to report and discuss more broadly how the study was integrated into other social processes beyond the boundaries of the study design. This practice should be expanded and adapted to journals focused on quantitative studies, encouraging authors who are part of equitable partnerships with Indigenous Peoples to reflect and recognize the contribution of community engagement to the research and use of the study results. Thus, we highlight recommendations of Indigenous scholars for academic journals to require studies to explicitly report how the affected community was involved in all stages of the research process [10]. Several studies in this review included a brief discussion on these issues in journals focused on quantitative environmental health and exposure sciences. Moreover, journals like Arctic Science accept contribution recognition and author’s positionality sections before the introduction, where Indigenous community members’ roles throughout the study can be detailed [96].

Indigenous Peoples have long advocated for self-determination and engagement with research conducted in their communities. They have been at the forefront of strategies to improve collaborations with non-Indigenous researchers. For example, the First Nations principles of ownership, control, access, and possession (OCAP^®), were created as a guiding tool for Indigenous Peoples and researchers to support Indigenous information governance and data sovereignty [97,98]. Thus, the scientific community must reciprocate these efforts and normalize conversations in scientific journals about community participation and the use of study results as part of broader acts of reconciliation with Indigenous Peoples [93]. These conversations in academic journals could provide valuable insights into pressing issues such as the uncritical expansion of policies mandating data openness, without considering how they can create mistrust among Indigenous partners and further exclude these populations from participating in research [99,100].

Finally, from the evidence of authors with Indigenous affiliation in Canada, the United States, and Suriname, we observed a potential pattern where community engagement and community use of the results were more likely in studies with authors affiliated with Indigenous organizations or institutions. This finding underlines the importance of including Indigenous authors in the project and its publication. Further analyses should be conducted to understand if having an Indigenous author influences community engagement practices and community use of study results or if the association mostly flows in the opposite direction. In addition, we identified an increasing trend in the proportion of articles with Indigenous authorship across the study period, particularly from 2019 to 2024, which is consistent with previous reviews [15]. The trends and effects of Indigenous authorship warrant future monitoring, given the revitalized calls from Indigenous scholars to expand the concept of “nothing about us without us” to academic publications [10,93], and the emerging strategies by some journals to promote community engagement of Indigenous Peoples either as authors or through meaningful roles in the research process.

Limitations and strengths

This study has several limitations. Our review did not include grey literature, which may be particularly important in identifying assessments conducted by public and private institutions, including Indigenous ones. Although this was beyond our focus on peer-reviewed research, there is room to expand the analysis to understand further how assessments of Indigenous food contamination are conducted beyond academia. More peer-reviewed and grey literature studies could be identified by searching for cited materials and publications or citing references and requesting access to reports from organizations that have monitored contamination levels.

Additionally, researchers who promote equitable partnerships with Indigenous Peoples may not be reporting on strategies to support community engagement and the use of the study results by the community in their scientific publications. Thus, our classification may not comprehensively reflect the characteristics of the research process, but the constraints established by editorial policies. Moreover, there could be cases where the limited information provided in articles regarding the role of the community in the research process is due to the community’s preference. However, in addition to the intrinsic value of evaluating researchers’ practices and discussions in scientific publications, we believe that our findings are indicative of general trends about the nature of current collaborations between environmental health researchers and Indigenous Peoples. Further research should be conducted to assess the quality of the community engagement activities and the use of study results beyond what is reported in scientific publications.

Our search may not have captured relevant research that either did not refer to the population or food system as Indigenous, or that was conducted in a language other than English. Despite not restricting the language of publication, we only searched for the terms in English, which could bias the countries included in the sample. An additional bias of the countries included in the study may emerge from the fact that some traditional communities do not identify as Indigenous or are situated in countries that do not recognize Indigenous Peoples. Although we expanded our search keywords following recommendations to capture a wide range of terms used for Indigenous Peoples, our sample is likely biased towards countries where Indigeneity is experienced in a particular way and Indigenous Peoples are officially acknowledged and recognized. Further research accounting for particular regions or contexts should be conducted.

Finally, our approach to identifying Indigenous affiliation may lead to some misclassification. For example, an Indigenous collaborator could choose not to disclose their affiliation in the paper or choose not to be listed as an author due to the added workload of co-authoring a publication. In addition, some journals may have guidelines that discourage adding an Indigenous affiliation, such as limits to reporting multiple affiliations and not allowing group authorship. Despite these limitations, this scoping review provided a systematic approach to include a broad range of articles exploring the contamination of Indigenous food systems. We followed PRISMA protocols and leveraged the flexibility of scoping reviews to discuss our research experience in the context of literature in the field.