RESUMO
Helicobacter pylori infection has been linked to gastrointestinal diseases including gastric cancer. High rates of H. pylori infection and gastric cancer have been reported in indigenous populations within the United States. We report whole-genome sequencing of three H. pylori isolates originating from Native American patients presenting with gastric disease.
RESUMO
The Water is K'é program was developed to increase water consumption and decrease consumption of sugar-sweetened beverages for young children and caregivers. The pilot program was successfully delivered by three Family and Child Education (FACE) programs on the Navajo Nation using a culturally centered curriculum between 2020 to 2022. The purpose of this research was to understand teacher and caregiver perspectives of program feasibility, acceptability, impact, and other factors influencing beverage behaviors due to the pilot program. Nine caregivers and teachers were interviewed between June 2022 and December 2022, and a study team of four, including three who self-identified as Navajo, analyzed the data using inductive thematic analysis and consensus building to agree on codes. Five themes emerged, including feasibility, acceptability, impact, suggestions for future use of the program, and external factors that influenced water consumption. The analysis showed stakeholders' strong approval for continuing the program based on impact and acceptability, and identified factors that promote the program and barriers that can be addressed to make the program sustainable. Overall, the Water is K'é program and staff overcame many challenges during the COVID-19 pandemic to support healthy behavior change that had a rippled influence among children, caregivers, teachers, and many others.
Assuntos
COVID-19 , Cuidadores , Criança , Humanos , Pré-Escolar , Pandemias , COVID-19/prevenção & controle , Bebidas , ÁguaRESUMO
Meteorological (MET) data is a crucial input for environmental exposure models. While modeling exposure potential using geospatial technology is a common practice, existing studies infrequently evaluate the impact of input MET data on the level of uncertainty on output results. The objective of this study is to determine the effect of various MET data sources on the potential exposure susceptibility predictions. Three sources of wind data are compared: The North American Regional Reanalysis (NARR) database, meteorological aerodrome reports (METARs) from regional airports, and data from local MET weather stations. These data sources are used as inputs into a machine learning (ML) driven GIS Multi-Criteria Decision Analysis (GIS-MCDA) geospatial model to predict potential exposure to abandoned uranium mine sites in the Navajo Nation. Results indicate significant variations in results derived from different wind data sources. After validating the results from each source using the National Uranium Resource Evaluation (NURE) database in a geographically weighted regression (GWR), METARs data combined with the local MET weather station data showed the highest accuracy, with an average R2 of 0.74. We conclude that local direct measurement-based data (METARs and MET data) produce a more accurate prediction than the other sources evaluated in the study. This study has the potential to inform future data collection methods, leading to more accurate predictions and better-informed policy decisions surrounding environmental exposure susceptibility and risk assessment.
Assuntos
Fonte de Informação , Urânio , Monitoramento Ambiental , Aeroportos , Exposição AmbientalRESUMO
In a large-scale environmental health population study that is composed of subprojects, often different fractions of participants out of the total enrolled have measures of specific outcomes. It's conceptually reasonable to assume the association study would benefit from utilizing additional exposure information from those with a specific outcome not measured. Partial least squares regression is a practical approach to determine the exposure-outcome associations for mixture data. Like a typical regression approach, however, the partial least squares regression requires that each data observation must have both complete covariate and outcome for model fitting. In this paper, we propose novel adjustments to the general partial least squares regression to estimate and examine the association effects of individual environmental exposure to an outcome within a more complete context of the study population's environmental mixture exposures. The proposed framework takes advantage of the bilinear model structure. It allows information from all participants, with or without the outcome values, to contribute to the model fitting and the assessment of association effects. Using this proposed framework, incorporation of additional information will lead to smaller root mean square errors in the estimation of association effects, and improve the ability to assess the significance of the effects.
RESUMO
Background: To estimate the efficacy of interventions to improve healthy eating, valid measures are essential. Although simple dietary intake tools have been developed with other populations, few have been culturally tailored and assessed for validity and reliability among Navajo. Objectives: This study aimed to develop a simple dietary intake tool tailored to Navajo culture, derive healthy eating indices, and assess their validity and reliability in Navajo children and adults and to describe the process used to develop this tool. Methods: A picture-sort tool using typically consumed foods was developed. Elementary school children and family members provided qualitative feedback in focus groups, used to refine the tool. Next, school-aged children and adults completed assessments at baseline and follow-up. Baseline behavior measures including child self-efficacy for fruits and vegetables (F&V) were examined for internal consistency. Healthy eating indices were derived from intake frequencies from picture sorting. The convergent validity of the indices and behavior measures for children and adults were examined. The reliability of the indices at the 2 time points was derived using Bland-Altman plots. Results: The picture-sort was refined from feedback provided by the focus groups. Baseline measures from 25 children and 18 adults were obtained. In children, a modified Alternative Healthy Eating Index (AHEI) and 2 other indices from the picture-sort were correlated with self-efficacy for eating F&V and had good reliability. In adults, the modified AHEI and 3 other indices from the picture-sort had significant correlations with adult abbreviated food frequency of F&V or obesogenic dietary index and had good reliability. Conclusions: The Navajo foods picture-sort tool developed for Navajo children and adults is proven to be acceptable and feasible to implement. Indices derived from the tool has good convergent validity and repeatability, supporting use in evaluating dietary change interventions in Navajo, with the potential for broader use of the approach in other underserved populations.
RESUMO
Background: Environmental exposures to metals in uranium mining wastes and drinking water were documented in more than half of the 1304 Navajo community members of the Diné Network for Environmental Health (DiNEH) Project, the first comprehensive assessment of exposures to these metals and community health on the Navajo Nation. Objective: Evaluate environmental exposures among participants who provided blood and urine samples using multiplexed autoantibody positivity as an early effect biomarker. Methods: Survey and geospatial location data, well water quality, and metals biomonitoring were used to assess exposures to mixed-metal wastes from 100 abandoned uranium waste sites. Results: We observed that the prevalence of multiplexed autoantibody positivity in 239 participants was more than double that reported for the U.S. population (27.2% v. 13.8%) even though the national prevalence was generated using a different assay, the HEp-2 cell-based antinuclear antibody test. Increased risk of multiplexed autoantibody screening positivity (OR = 3.07,95%CI 1.15-8.22) was found among DiNEH study people who lived close to uranium mine and milling wastes and consumed metals in drinking water. Associations for females were even stronger when they lived closed to contaminated uranium mining and milling sites. Anti-U1-RNP antibodies were associated with water consumption of nickel. Conclusion: Proximity to waste sites and consumption of metals in water even below current drinking water standards were associated with perturbations of immune tolerance. These findings are consistent with previous studies of autoimmunity in the local population and demonstrate that multiplexed autoantibody screening method has a potential as sentinel indicator of exposures to environmental metals. Impact statement: This is the first, community-engaged environmental health study in exposed Navajo communities that applied clinical multiplexed testing in risk assessment of environmental metals associated with abandoned, unremediated uranium mining and milling waste sites. Routine clinical autoimmunity measures could be used as early effect biomarkers of environmental metal exposures.
RESUMO
BACKGROUND: On August 5, 2015, the Gold King Mine Spill (GKMS) resulted in 3 million gallons of acid mine drainage spilling into the San Juan River impacting the Diné Bikeyah (traditional homelands of the Navajo people). The Gold King Mine Spill Diné Exposure Project was formed to understand the impacts of the GKMS on the Diné (Navajo). Reporting individualized household results in an exposure study is becoming more common; however, materials are often developed with limited community input with knowledge flowing in one direction - from researcher to participant. In this study we examined the development, dissemination, and evaluation of individualized results materials. METHODS: In August 2016, Navajo Nation Community Health Representatives (Navajo CHRs) sampled household water, dust, and soil, and resident blood and urine for lead and arsenic, respectively. From May-July 2017, iterative dialogue with a wide range of community partners and a community focus groups guided the development of a culturally-based dissemination process. In August 2017, Navajo CHRs reported individualized results and they surveyed the participants on the report-back process at that time. RESULTS: All of the 63 Diné adults (100%) who participated in the exposure study received their results by a CHR in person and 42 (67%) completed an evaluation. Most of those participants (83%) were satisfied with the result packets. Respondents ranked the individual and overall household results as the most important information they received (69% and 57%, respectively), while information on metals exposures and their health effects were the least helpful. CONCLUSIONS: Our project illustrates how a model of environmental health dialogue, defined by iterative, multidirectional communication among Indigenous community members, trusted Indigenous leaders, Indigenous researchers, non-Indigenous researchers, can improve reporting individualized study results. Findings can inform future research to encourage multi-directional environmental health dialogue to craft more culturally responsive and effective dissemination and communication materials.
Assuntos
Ouro , Indígenas Norte-Americanos , Humanos , Exposição Ambiental/análise , Saúde Ambiental , Saúde PúblicaRESUMO
BACKGROUND AND OBJECTIVE: Marked inequities in access to autism services and related health outcomes persist for U.S. children, undermining broader initiatives to advance the population's health. At the intersection of culture, poverty, and ruralness little remains known about autism in many Indigenous communities. This qualitative study on the lived experiences of Navajo (Diné) parents raising a child with autism sought to identify factors affecting access to services. METHODS: A Diné researcher conducted in-depth interviews with 15 Diné parents of children with autism living in or around the Navajo Nation. A directed content analysis approach was used to identify themes, subthemes, and connections between themes. RESULTS: Twelve overarching themes emerged on Diné parents' experiences accessing autism diagnostic and treatment services, as well as ways access to autism services can be improved. The following themes were related to diagnosis: the diagnostic process was often emotionally fraught; long wait times of up to years for diagnostic services were commonplace; limited clinician training and cultural humility impeded access to diagnostic services; and adequate health insurance, Indian Health Service referrals, care coordination, financial aid for travel, and efficient evaluation facilitated diagnosis. Themes on treatment access were as follows: parent perceptions of the extent to which an autism service helped their child affected access; social support helped parents to access treatment; obtaining referrals and care coordination influenced treatment access; treatment costs affected access; and service availability and geographic proximity impacted treatment access. Themes on ways to improve access to autism services were as follows: greater autism awareness is needed; autism-focused support groups may be helpful; and increased availability and quality of autism services across and around the Navajo Nation is paramount. CONCLUSIONS: Diné parents' access to autism services was dynamically affected by sociocultural factors that must be addressed in future health equity-oriented initiatives.
Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Serviços de Saúde da Criança , Humanos , Criança , Transtorno Autístico/diagnóstico , Transtorno Autístico/terapia , Pesquisa Qualitativa , Pobreza , Acessibilidade aos Serviços de Saúde , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/terapiaRESUMO
This paper explores how Indigenous-led research reframes the impacts and response to environmental disasters in the context of acid mine spills in rural communities of the Southwest United States. The collaborative research project addressing the Gold King Mine Spill (GKMS) designed qualitative methodologies that center Indigenous worldviews and contribute to broader understandings of environmental justice. The research team, led by Diné scholars and community leaders, gathered qualitative responses from 123 adult participants in twelve focus groups from three rural communities on the Navajo Nation. The project incorporated fluent Diné speakers and cultural consultants to lead focus groups in a manner consistent with cultural worldviews. The analysis of the focus group data resulted in original findings that reframe previous understandings of environmental harm by broadening the boundaries to include: 1) social relations across time; 2) social relations across space; 3) spiritual relations; and 4) restoring balance. The findings allow for greater insight into the colonial context of disaster on rural and Indigenous lands and confronts colonial-rooted disasters through Indigenous-informed political action.
RESUMO
From the start of the COVID-19 pandemic on the Navajo Nation, Diné (Navajo) traditional knowledge holders (TKHs), such as medicine men and women and traditional practitioners, contributed their services and healing practices. Although TKHs are not always fully acknowledged in the western health care system, they have an established role to protect and promote the health of Diné people. To date, their roles in mitigating the COVID-19 pandemic have not been fully explored. The purpose of this research was to understand the social and cultural contexts of the COVID-19 pandemic and vaccines based on the roles and perspectives of Diné TKHs. A multi-investigator consensus analysis was conducted by six American Indian researchers using interviews with TKHs collected between December 2021-January 2022. The Hózhó Resilience Model was used as a framework to analyze the data using four parent themes: COVID-19, harmony and relationships, spirituality, and respect for self and discipline. These parent themes were further organized into promoters and/or barriers for 12 sub-themes that emerged from the data, such as traditional knowledge, Diné identity, and vaccine. Overall, the analysis showed key factors that could be applied in pandemic planning and public health mitigation efforts based on the cultural perspective of TKHs.
Assuntos
COVID-19 , Indígenas Norte-Americanos , Feminino , Humanos , Masculino , Pandemias , Saúde Pública , Espiritualidade , População NavajoRESUMO
Digital storytelling is a decentering methodology in health promotion that positions the storyteller as an expert to create a narrative of their lived experiences. This article describes using a two-phase digital storytelling process within the Diné (Navajo) Educational Philosophy framework to guide the development of a culturally grounded curriculum plan that actively engages Diné youth in exploring health professions pathways in their community. The first phase consisted of developing a high school digital storytelling team by training three Diné youth attending high school on the Navajo Nation located in southwest United States, in digital storytelling. In the second phase, the high school digital storytelling team worked collaboratively with seven Diné students enrolled at the local tribal college to develop digital stories about navigating from high school to college. Data from seven completed digital stories were analyzed with assistance from a community advisory board to identify asset-based themes that contributed to positively transitioning from high school to a tribal college. The results revealed several strategies for successful transitions from high school to a public health college major. The culturally relevant strategies and stories were incorporated into a school-based health professions pathway curriculum plan for Diné youth.
Assuntos
Indígena Americano ou Nativo do Alasca , Indígenas Norte-Americanos , Adolescente , Humanos , Saúde Pública , Comunicação , Narração , EstudantesRESUMO
Navajo children disproportionately experience poor asthma outcomes. Following a one-year community engagement period with key stakeholders from the Navajo Nation, the Community Asthma Program (CAP) was created using evidenced based programs with the goal of reducing asthma disparities among Navajo children. CAP is being evaluated with a six-year, multi-site step-wedge design in three Navajo communities: Tuba City, Chinle and Fort Defiance, Arizona. The primary outcome is asthma exacerbations defined as use of systemic oral corticosteroids, asthma hospitalizations, asthma related ED visits, and ICU admissions. Asthma exacerbations will be measured using data from the electronic medical records of the three community health care centers. Secondary outcomes include will changes in asthma-related events and asthma control. The RE-AIM ( R each and representativeness, 2) E ffectiveness, 3) A doption, 4) I mplementation, and 5) M aintenance) framework is being used to guide the implementation evaluation which includes iterative collection and analysis of process data to identify facilitators and barriers, describe relevant organizational contexts, and inform strategies for dissemination. The CAP intervention requires community engagement and participation, building community capacity, incorporating evidenced-based guidelines and practices while ensuring program strategies actively involve Navajo community members during all steps of the intervention. The outcome of this trial will allow us to determine the effectiveness of a multi-component, community-focused intervention to improve asthma in a tribal community.
RESUMO
In 2014, the Navajo Nation Healthy Diné Nation Act (HDNA) was enacted and permanently approved in 2020; HDNA places a 2% surtax on unhealthy foods and beverages, while other 2014 legislation exempted healthy food items from the 6% regular sales tax. Little is known about Navajo Nation store manager/owner perspectives toward the HDNA and how best to support stores to implement the legislation. Purposive sampling was used to ensure a balanced sample of correct HDNA implementers, incorrect HDNA implementers, and stores which made healthy store changes over the past 6 years. Three community-based interviewers collected surveys by phone or in-person. Frequency of closed-ended questions was quantified, and open-ended responses were coded using thematic analysis. Of 29 identified sample stores, 20 were interviewed to reach saturation. Eleven of 20 stores made changes improving their healthy food environments. Barriers included lack of equipment (6/20) and low consumer demand (5/20). Facilitators included consumer awareness and increased produce supply options (5/20). Sixteen of 20 stores supported HDNA continuation. Facilitators to HDNA implementation included orientation and informational materials (6/20) and promotion of tax-free items (5/20). Barriers included confusion about the tax (6/20) and tax exemption (5/20). Suggestions for support included printed materials (6/20) and store training (5/20). HDNA benefits included greater awareness of healthy choices among staff (7/20) and customer-community members (2/20). Most managers and owners expressed receiving support for healthy store changes and HDNA, but also identified a need for added resources and support. Findings inform legislative action to promote timely and appropriate uptake of HDNA, and support equitable, healthy food systems.
Assuntos
Comércio , Abastecimento de Alimentos , Humanos , Alimentos , Preferências Alimentares , Política NutricionalRESUMO
To inform women of the Navajo Nation of safety measures implemented to minimize COVID-19 virus exposure during screening and treatment procedures at Navajo Nation based health care facilities, the Navajo Nation Breast and Cervical Cancer Prevention Program (NNBCCPP) and the University-based Partnership for Native American Cancer Prevention Program (NACP) collaborated to develop a podcast to describe the continued availability of services. During the COVID-19 pandemic, women of all ages and ethnicities in the US needing breast and cervical cancer prevention screenings and treatment, have been hesitant to seek services given the advice to avoid crowded spaces and maintain physical distancing. Epidemiological trends indicate that proactive, intensive strategies are needed in Native American communities for early detection and treatment to support early cancer diagnosis and improve cancer survival. The NNBCCPP and Northern Arizona University (NAU) through the National Institute of Health's National Cancer Institute funded NACP had a nascent partnership prior to the onset of COVID-19 pandemic. This partnership relied on face-to-face interaction to allow for informal social interaction, facilitate clear communication and support continued trust building. To adhere to federal, state and tribal recommendations to minimize gatherings and to stay in-place to minimize the spread of the virus, the Navajo Nation and NAU restricted, and in most cases would not approve employee travel for partnership meetings. The plans to develop a podcast necessitated bringing additional members into the collaboration who were unfamiliar to the original partners and due to travel restrictions, required all interactions to be remote. This expanded group met virtually to develop a script, record and edit the podcast. More importantly, group members had to build and maintain trust over months of communicating via a teleconference video platform. This collaborative addressed challenges related to unstable Internet connections and periodic stay-at-home policies; thus, these emerging partners had to modify social and professional communication to respect and accommodate the stress and uncertain circumstances created by the pandemic on the citizens and employees of Navajo Nation. This case study describes strategies used to maintain and respect all members of the partnership.
Assuntos
COVID-19 , Indígenas Norte-Americanos , Neoplasias do Colo do Útero , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Atenção à Saúde , Feminino , Humanos , Pandemias , Universidades , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controleRESUMO
The Navajo Nation is the largest Native American reservation by area and citizenship. The study sought to provide the first large-scale examination of ocular pathology within this population. A retrospective review of all Navajo patients seen at Moran Eye Center Navajo Nation Outreach Clinics from 2013 to 2021 for demographics, visual acuity, refractive, and eye pressure data was undergone. Further variables included comorbidity and eye diagnoses among patients at these clinics. Results: First-time patient visits totaled 2251 from 2013 to 2021. The median age was 53 (range, 18 to 92), and clinics had a predominance of female patients (1387:864). Among patients presenting without glasses, 20.67% (198/958), 9.71% (93/958), and 3.13% (30/958) had mild visual impairment (VI), moderate to severe VI, and blindness, respectively. Cataracts were the most common cause of blindness in these patients (40%, 12/30) and the need for glasses was the second most common cause (33%, 10/30). From 2016 to 2021, 17.71% (48/271) of diabetic patients were diagnosed with diabetic retinopathy (DR). Within the subset of Navajo patients that presented without any correction, 73% of bilateral blindness was preventable via glasses prescription or cataract surgery. This study comments on questions of equitable care for Navajo patients.
RESUMO
Background: In 2014, the Navajo Nation passed the Healthy Diné Nation Act (HDNA), which applies an additional 2% tax on unhealthy foods and beverages and a waiver of Navajo sales tax on healthy foods and beverages. However, the HDNA's impact on purchasing behavior has not been explored. Objectives: We assessed beverage and produce purchasing trends among shoppers at small Navajo stores between 2017 and 2019, shopper characteristics associated with buying water, and whether HDNA awareness was associated with purchasing behaviors. Methods: A total of 332 shoppers at 34 stores in 2017 and 274 shoppers at 44 stores in 2019 were surveyed to assess HDNA awareness and same-day purchasing of water, sugar-sweetened beverages (SSBs), fruits, and vegetables. Hypotheses were tested using chi-square analyses and multivariate analysis. Results: Water purchasing among respondents increased significantly from 2017 to 2019 (24.4% to 32.8%; P = 0.03). Shoppers in 2019 were 1.5 times more likely to purchase water compared with 2017 (adjusted P = 0.01). There was a trend toward reduced SSB purchasing (85.8% in 2017, 80.3% in 2019, P = 0.068), while produce purchasing remained unchanged over time, at approximately 17%. Shoppers were more likely to buy water if they relied on that store for the majority of their groceries (P = 0.006) and if they did not have their own transportation to get to the store (P = 0.004). Most shoppers (56.6%) were aware of the HDNA; of these, 35.6% attributed healthier habits to the HDNA, most commonly buying more healthy drinks (49.2%), fewer unhealthy drinks (37.7%), more healthy snacks (31.1%), and fewer unhealthy snacks (26.2%). Conclusions: Shopper habits at small stores located on the Navajo Nation have shifted towards healthier purchasing from 2017 to 2019. Shoppers who were aware of the HDNA reported purchasing more healthy and fewer unhealthy food and drinks as a result of this legislation.
RESUMO
BACKGROUND: MPV17-related mitochondrial DNA maintenance defect (MPV17 deficiency) is a rare, autosomal recessive mitochondrial DNA depletion syndrome with a high mortality rate in infancy and early childhood due to progression to liver failure. Liver transplantation for children with MPV17 deficiency has been considered controversial due to uncertainty about the potential progression of extrahepatic manifestations following liver transplantation. METHODS: We describe our institution's experience for two infants diagnosed with infantile MPV17 deficiency who presented in acute on chronic liver failure, but with normal development and normal neurological status who successfully underwent liver transplantation. RESULTS: Both patients underwent successful liver transplantation with normal development and neurological status at 3 years and 16 months post-transplant, respectively. CONCLUSIONS: In this rare disease population, we describe two infants with MPV17 deficiency who underwent liver transplantation for acute on chronic liver failure who continue to have normal development, without progression of neurological disease. MPV17 deficiency should not be considered a contraindication to liver transplantation.
Assuntos
Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Criança , Pré-Escolar , DNA Mitocondrial/genética , Transtornos Heredodegenerativos do Sistema Nervoso , Humanos , Lactente , Hepatopatias , Proteínas de Membrana/genética , Doenças Mitocondriais , Proteínas Mitocondriais/genética , Doenças do Sistema Nervoso PeriféricoRESUMO
Native American populations are systematically marginalized in the healthcare and public health workforce. One effective approach to reduce health disparities and improve health care delivery among Indigenous populations is to train more Native American health professionals who integrate academic and cultural knowledge to understand and influence health behaviors and perspectives. Diné College partnered with Northern Arizona University to develop the Navajo Native American Research Center for Health (NARCH) Partnership, funded by the National Institutes of Health. The high school component of the Navajo NARCH Partnership created the Indigenous Summer Enhancement Program (ISEP), a 1-week summer training program providing exposure to health careers and mentorship in pursuing public health careers for Native American high school students. ISEP utilizes the Diné Educational Philosophy (DEP), a Navajo conceptual framework to serve as the foundation of the program. In 2020-2021, due to COVID-19 restrictions, the DEP model had to be incorporated in the Navajo NARCH high school virtual program activities. ISEP used 2018 and 2019 past program evaluation data to inform the virtual programming. Students' perception of the program was collected using an online Qualtrics evaluation questionnaire. Students stated appreciation for program staff, fellow students, peer mentors and culturally relevant learning experiences in both virtual and in-person environments. Recommendations included: expanding the length of ISEP and continuing the hands-on activities and Public Health Leadership series.
Assuntos
COVID-19 , Saúde Pública , COVID-19/prevenção & controle , Escolha da Profissão , Humanos , SARS-CoV-2 , Estudantes , Estados Unidos , Indígena Americano ou Nativo do AlascaRESUMO
BACKGROUND: Indoor air pollution is associated with adverse health effects; however, few studies exist studying indoor air pollution on the Navajo Nation in the southwest U.S., a community with high rates of respiratory disease. METHODS: Indoor PM2.5 concentration was evaluated in 26 homes on the Navajo Nation using real-time PM2.5 monitors. Household risk factors and daily activities were evaluated with three metrics of indoor PM2.5: time-weighted average (TWA), 90th percentile of concentration, and daily minutes exceeding 100 µg/m3. A questionnaire and recall sheet were used to record baseline household characteristics and daily activities. RESULTS: The median TWA, 90th percentile, and daily minutes exceeding 100 µg/m3 were 7.9 µg/m3, 14.0 µg/m3, and 17 min, respectively. TWAs tended to be higher in autumn and in houses that used fuel the previous day. Other characteristics associated with elevated PM exposure in all metrics included overcrowded houses, nonmobile houses, and houses with current smokers, pets, and longer cooking time. CONCLUSIONS: Some residents of the Navajo Nation have higher risk of exposure to indoor air pollution by Environmental Protection Agency (EPA) standards. Efforts to identify the causes and associations with adverse health effects are needed to ensure that exposure to risks and possible health impacts are mitigated.