Environmental Research Section A 86, 140}148 (2001)doi:10.1006/enrs.2001.4250, available online at http://www.idealibrary.com on

Lifestyles, Diets, and Native American ExposureFactors Related to Possible Lead Exposures and Toxicity

Stuart Harris and Barbara L. Harper

Special Science and Resources Program, Confederated Tribes of the Umatilla Indian Reservation, P.O. Box 638, Pendleton, Oregon 97801;and AESE, Inc., 44803 East Alderbrook Court, West Richland, Washington 99353

Received May 10, 2000

1Abbreviations used: IEUBK, integrated exposure uptake bio-kinetic model for lead in children; CERCLA, ComprehensiveEnvironmental Response, Compensation, and Liability Act;ARAR, applicable, relevant, and appropriate regulations; NEPA,National Environmental Protection Act; RCRA, Resource Conser-vation and Recovery Act; IRB, institutional review board; ROD,record of decision; HANES, Health and Nutrition Examination

Lead exposure is still a national concern, and it ispossible that Native Americans who live on reserva-tions and pursue traditional lifestyles may be athigher risk through both their unique exposureproAles and their potentially greater sensitivity.A major component of the exposure assessment isthe diet. For tribal members, traditional lifestylesthat include native foods, medicines, and tradi-tional practices have evolved and proven to be themost healthful over many thousands of years ofcoexistence with the environment. However, a com-pletely traditional diet may not be fully availablefor a variety of reasons; so, one must also considerthe adverse health consequences caused by the lossof healthy native foods and medicines, the contami-nation of remaining native foods, the inability topractice one’s religion, and the possibly lower qual-ity of the substitute diet. Health evaluations of leadexposure on reservations should therefore considerat least two types of diets in addition to the typicalsuburban diet: (a) traditional diets composed of na-tive foods and medicines that would result in in-creased exposure if the plants and animals arecontaminated and (b) disadvantaged or commodityfood diets that result in widespread vitamin andmineral deAcits of the sort known to increase ab-sorption of and response to lead. Additional expo-sure to lead might come from reservation housingwhich is often older, although the prevalence oflead-based paint on reservations is unknown. Thedegree of physiological response could also be affec-ted by widespread exposures to other neurotoxins(such as mercury and PCBs in Ash), underlying dis-ease patterns, and genetics. Although each of thesefactors is plausible, their prevalence singly or incombination is unknown. Any correlation betweenthese risk factors and blood lead levels on reserva-tions is also unknown. This paper begins to address

This paper re8ects the views of the authors and should notnecessarily be interpreted as tribal governmental policy.

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0013-9351/01 $35.00Copyright ( 2001 by Academic PressAll rights of reproduction in any form reserved.

these gaps by discussing the range of traditionaland current diets that may exist among tribes andmethods for developing a whole-lifestyle exposurescenario that is appropriate for an individual tribe.Some of the factors discussed in this paper may notapply to the large population of Native Americanswho live in urban situations. ( 2001 Academic Press

Key Words: Native American; subsistence diet;cultural; lead (Pb); risk.

INTRODUCTION

When estimations of lead exposure to tribalmembers are made through the use of models, theiroverall activity and exposure patterns must beunderstood well enough to be put into the formatrequired by the exposure model (e.g., the IEUBK1

model or the CERCLA exposure scenarios). Dietaryexposures are a critical element of exposure modelsand need to be examined in some detail, especiallyfor Native Americans. However, our eventual goal astribal technical staff is not primarily to increaseprecision about a single exposure pathway such asdiet, but rather to increase overall understandingabout multipathway exposures, the possibility thattribal populations may also be more physiologicallysensitive, and the effects of environmental contami-nation on the entire environmentally based lifestyle.

Any exposure model, whether it is the IEUBK orstandard CERCLA exposure scenarios, needs to be

Survey; NHANES, National HANES; RDA, recommended dailyallowance; PUFA, polyunsaturated fatty acid; SES, socioeconomicstatus.

NATIVE AMERICAN DIETS AND EXPOSURE FACTORS 141

speci7cally derived for the population to which it isapplied. The process for developing tribally appro-priate exposure scenarios centers around the under-standing of key aspects of traditional lifestyles forthe particular tribe. The range of speci7c lifestylesand exposure factors will vary widely from tribe totribe because each tribe’s culture is a unique productof its own history, watershed, food sources, andhomeland. Therefore, speci7c dietary and activitypatterns will vary as widely as climate and resourcesvary. Although every tribe has a different culture,tradition, and religious practice, many of these life-styles are environmentally oriented and generallyresult in higher environmental contact rates. Fur-thermore, this range of traditions and lifestylesexists within a varying context of tribal governmentsovereignty, federal trusteeship obligations, treatylaw, and religion. It is important to begin witha basic understanding of these laws and principles.

GENERAL PRINCIPLES

Maintaining a homeland with a clean functioningecosystem where past, present, and future genera-tions may live is a dominant feature of tribal integ-rity, health, religion, and everyday life. TribalNations are fundamentally concerned with protect-ing these features and draw on their sovereignstatus to do so. The sovereign status of tribal govern-ments means that the tribal governments should beaccorded at least the same status as state govern-ments. Many tribal governments are full-servicegovernments providing services from sidewalks tostreet signs and housing to healthcare. Tribes areincreasingly obtaining authority to administer andenforce environmental laws and are actively protect-ing their resources both on and off reservations. Forthose tribes that have treaties with the UnitedStates government, the most basic tenet of the treat-ies, under the cannons of construction of constitu-tional law, is that the treaties were intended toprotect the resources on which the traditional relig-ious lifestyle and community health depend. Theterm sovereignty also refers to self-determination,which is of paramount importance and is part of thereason that assimilation into the dominant society isso strenuously resisted. If traditional practices haveto be reduced because environmental contaminationmakes them unsafe, the culture is diminished.People will often knowingly continue to use con-taminated resources rather than give up their cul-ture and religion, which means that a differentapproach to education and health care interventionis needed.

Our job as tribal employees is to help protect tribalrights, natural and cultural resources, individualand community health, and traditional lifestyles.These lifestyles and the resources on which theydepend are protected by treaty (for many but not alltribes), religious freedom laws, federal trusteeshipobligations, and modern environmental legislation.Risk assessment in Indian country must thereforestart with an understanding that the legal (ARAR)landscape is more complex than in nontribal Super-fund or regulatory situations. This legal landscapeincludes but is not limited to treaties, CERCLA,National Historic Preservation Act, NEPA, Ameri-can Indian Religious Freedom Act, RCRA, CleanWater Act, Safe Drinking Water Act, EndangeredSpecies Act, and Executive Orders on consultation,environmental justice, and sacred lands. Becausethe speci7c ARAR landscape depends on the indi-vidual tribal situation and affected resources, eachTribal Nation must be consulted before startinga regulatory or remedial action that involves reser-vation lands, ceded lands, public lands with tribalhistoric use, or other lands that contain or couldaffect tribally important resources. Focused healthintervention studies would also bene7t from a betterunderstanding of tribal history and context so thatpitfalls such as the assumption that it is acceptableto simply give up a cultural practice to prevent expo-sure can be avoided.

TRADITIONAL HOLISTIC LIFESTYLES

Traditional lifestyles are part of an ancient tribalheritage, and this lifestyle is still practiced by manymore people than suburban society realizes. Know-ing how to gather, prepare, and use native foods andmedicines is not an option or preference, but is re-quired as part of living a traditional religious life.Tribal religious practices are recovering from yearsof prohibition, and tribal heritage is increasinglyrecognized as a very important part of recoveringfrom ‘‘post-colonial traumatic stress syndrome’’ andpreserving community integrity and personal andcommunity health (Duran and Duran 1995). Evalu-ating impacts to tribal health requires knowledge ofmore than just dietary practices (Thornton, 1998).

Because these traditional lifestyles are so closelybound to every aspect of the environment, any spe-cies is likely to be used in many ways, either directlyin the diet as food or medicine or as an item ofcultural or religious signi7cance. Even if culturalitems do not contribute a direct exposure, their losscould affect the practice of the traditional religion,thus causing human stress that could in turn affect

142 HARRIS AND HARPER

response to toxicants. For instance, a resource atlocation A might be required to gather food at loca-tion B to conduct a ceremony at location C. Thus,while diet is a major exposure pathway, risk man-agers must realize that the breaking of a dietaryexposure pathway by denial of access to a resource orarea is likely to have health and religious conse-quences of its own. We recommend that any expo-sure or dietary study of Native Americans that isdone to support a remedial action or interventionshould have four parts: estimation of exposurethrough the diet and other routes, assessment of theconsequences of contamination on natural and cul-tural resources and their use, assessment of theconsequences of the breaking of a nutritional andtraditional religious link to reduce or avoid expo-sure, and consideration of the health effects ina population whose health and nutritional statusmay already be impaired.

EXPOSURE SCENARIOS BASED ON HOLISTICLIFESTYLES

Suburban exposure scenarios re8ect relatively fewpathways and environmental contacts, but triballifestyles are inseparable from the environment. Un-like suburban exposure scenarios, every element ofa traditional lifestyle is intertwined with the environ-ment through health, food, medicine, religion, educa-tion, and/or social activities, to name some of the moreobvious linkages. Traditional duties and thereforeexposure patterns are also often age and gender spe-ci7c. Although conventional federal risk manage-ment goals are often focused on a single resource(e.g., groundwater) or location (e.g., a contaminatedhotspot), tribal perspectives are likely to seek protec-tion of an entire ecosystem, watershed, or lifestyle.

One example of a subsistence exposure scenariobased on the lifestyles of three tribes and developedfrom within those tribes (Umatilla, Walla Walla, andCayuse) has been published (Harris and Harper,1997). The process for developing the subsistencescenario involved substantial preparation and know-ledge of the community (and in this case actualenrollment in the tribe). In addition to demonstrat-ing accountability and integrity (a form of informedconsent), we also developed informal rules for pro-tecting con7dentiality and intellectual propertyrights. Because these scenarios were developed sol-ely within the tribe, there was no internal institu-tional review board (IRB) available, but our personaltraining in biomedical ethics and IRBs enabled us tofollow the intent of the IRB process and to obtain anequivalent review at the tribal policy level before

proceeding. Tribal members do not regard their livesas objects of anthropological study to which aca-demics have rights of access for scienti7c reasons (asre8ected in bioprospecting, genome, and repatri-ation con8icts). They similarly do not regard ex-ternal IRBs as necessarily suitable for the grantingof permission for biomedical studies of tribal mem-bers, and the anthropological community does noteven have the equivalent of an IRB process. The‘‘interviews’’ of community members also delineatedwhat could be revealed and what could not abouttraditional environmental knowledge, communityvalues, habitat-speci7c activity patterns, and impor-tant aspects of the ecology and ecocultural land-scape. The interviews also identi7ed families withstrong cultural practices. A statistical cross-sectionwith a small sample size could miss entire familieswith special skills (such as 7shing families who 7shfor themselves, for ceremonies, and for other mem-bers) and who therefore consume nonaverage diets.These people should not be regarded as statisticaloutliers with worst-case exposures’ but as peopleliving and performing a unique and important com-munity service and who require special protection(or oversampling).

The information from the interviews was sum-marized in a format for model input (i.e., with expo-sure frequency and duration and total dietaryamounts of vegetation, meat, and 7sh). The subsis-tence scenario also included a sweat lodge pathway,which consists of volatilization of water into a con-7ned space at a certain frequency and duration andwhich is a primary exposure pathway if the water iscontaminated. From a risk management perspect-ive, it must be recognized that use of the sweat lodgeis a religious activity, so it is not appropriate to limitthe evaluation to contaminants that exceed drinkingwater standards or to assume that use of the sweatlodge can be limited as a risk ‘‘mitigation’’ measure.Similarly, the overall exposure scenario uses an ex-posure duration of 70 years rather than 30 years orless because tribal members are not mobile and can-not leave the homeland, which is the source of theirsustenance, religion, and history, without mentaland physical health consequences.

DIETS AND COEXISTING RISK FACTORS

We recommend evaluation of different types ofdiets that coexist among tribal members, ratherthan a central tendency averaged across a variety ofdistinct diets (Table 1). The type of survey tool andthe targeted information will vary with the riskmanagement goal. For example, current diets might

TABLE 1Types of Diets That Might Be Selected According to

the Risk Management Goal

Type of dietary survey Typical driver or goal

1. Current diets evaluated withcross-sectional dietary sur-veys; may be on or off reserva-tion

Health intervention for speci7cdiseases, often within a speci-7c group based on age, gen-der, and so on; market basketsurveys

2. Fully traditional diet withsubsistence exposure scen-ario

Protection of treaty rights andreligion; remedial goals for7nal ROD; multigenerationprotection of small gene pools

3. Modern reservation condi-tions;poverty and commod-ity foods (high fat, low 7ber)

Correction of speci7c nutri-tional de7cits; socioeconomicor public health evaluation

4. Partial or targeted dietarysurvey; may be triggered bycontamination of a particularfood, place, or resource or bya speci7c research question

Key factors related to speci7cgenetic (ethnopharmacology)makeup (e.g., milk intakerate related to lactose intoler-ance); identi7cation of speci-7c contaminated food source(e.g., mercury or PCBs in 7sh)

2An example of echinacea overharvest can be found athttp://www.billingsgazette.com/region/980801

}reg004.html. This

article also states that the ‘‘Fort Berthold Indian Reservation inNorth Dakota passed a tribal law forbidding harvests after zeal-ous digging rendered the once-abundant plant a rarity.’’

NATIVE AMERICAN DIETS AND EXPOSURE FACTORS 143

be the focus if the goal is health intervention tocombat modern diseases such as obesity, heart dis-ease, or diabetes, but native foods and medicines ora more traditional food ingestion rate might be thefocus if a speci7c resource is contaminated and thegoal is to restore full tribal use of that resource.

Some of the recent literature about Native Ameri-can dietary patterns is presented here. Several pa-pers recognized that the investigator must workwithin the culture for the study to be sensitiveenough to get reliable data. Additionally, the investi-gator must understand the culture well enough todesign culturally competent surveys (Teufel, 1997),with direct partnerships working the best (Schelland Tarbell, 1998; Harris and Harper, 1997).

Cross-sectional dietary surveys. Surveys of cur-rent diets are performed most often as part of a dis-ease intervention study, although Broussard et al.(1995) noted that few detailed studies of diet orphysical activity levels of contemporary NativeAmericans have been published. This is improvingwith the new emphasis on contamination of subsis-tence foods. Byers (1996) cited the earlier studies ofcurrent diets (Wolfe and Sanjur, 1988; Teufel andDufour, 1990; Brown and Brenton, 1994; Russellet al., 1994; Nobmann et al., 1992; Story et al., 1986)as part of a Native American cancer conference andfound modern reservation diets to be high in fat and

low in fruits and vegetables. Zephier et al. (1977)studied the modern diets of 10 tribes in relation tocardiovascular disease and found generally high-fat,low-7ber diets, with older participants eating betterpresumably because they made a conscious effort todo so. The Exposure Factors Handbook (EPA, 1997)contains additional current dietary information.Some of these studies were performed on reserva-tions, while others were designed to extract a racialsubset of the general national dietary data and mayor may not have focused on actual reservation condi-tions. More and more information about the relationof diabetes to modern diets and exercise levels isappearing, and this is shedding light on the composi-tion and healthfulness of traditional diets. Addi-tional papers on speci7c nutritional status areappearing and are helping in 7lling data gaps.Whereas cross-sectional surveys are certainly appro-priate to use where intervention for a health condi-tion is the goal, they may miss entire classes of peoplewho are more traditional, people who are quite welloff or the poorest, those who do not have telephones ormeans to travel to health clinics (where participantsare often recruited), or those who lack con7dence inwestern medicine. There are also a number of factorsthat may skew a participant’s answer, such as a be-lief that revealing con7dential information aboutnative plants and medicines could have adverse con-sequences such as the potential for losing a resourceto commercial interests once it is identi7ed(echinacea2 is a case in point).

Surveys of traditional/subsistence diets. Theseare found primarily in the anthropology literature,which was not searched for this paper, althoughmore papers have appeared in the biomedical litera-ture recently. There are several de7nitions of ‘‘sub-sistence,’’ and the term has been applied both toliving completely off the land and to recreationalsportsmen who eat what they catch or kill (Endter-Wada, 1966). Byers (1966) surveyed the anthropol-ogy literature and concluded that traditional orsubsistence diets were generally low fat and high7ber, although this is generally discussed qualitat-ively rather than on a nutritional or caloric basis.Harris and Harper (1997) investigated traditionaldiets consumed by tribal members who were recog-nized by themselves and by others as being ‘‘tradi-tional’’ and estimated the caloric content, which

144 HARRIS AND HARPER

compared well with earlier caloric estimates of thesame diet (Hunn, 1990). It is important that moreinformation about traditional diets be published inthe medical literature because there are indicationsthat a return to native diets is effective in some casesof diabetes (Norrell, 1998; deGonzague et al., 1999;many others) and other diseases, but care must betaken to avoid exploitation of this information bycommercial interests or revelation of tribal propri-etary information.

Modern reservation conditions. Reservation con-ditions are among the poorest in the country, al-though this varies considerably. While a few tribeshave bene7ted substantially from gaming, and manyothers have been able to make some improvementsin their social and health infrastructure, unemploy-ment is still extremely high and living conditions areextremely poor on many reservations. This is alsore8ected in reservation diets, which are often vit-amin and mineral de7cient. A Navajo HANES reportshowed that the diet tended to be low in fruits andvegetables, high in fat, and below the RDA for sev-eral vitamins and minerals, including calcium andiron (which would affect lead absorption) (Ballewet al., 1997). Hopi students had diets that were highin fat and low in calcium, zinc, and VitaminD (Brown and Brenton, 1994). Wolever et al., (1997)reported that Ojibwa-Cree diets were high in fat andlow in 7ber and had a high prevalence of inadequatevitamin A, calcium, vitamin C, and folate. Montanareservations also had diets low in greens, fruits, andvegetables (Nelson et al., 1997), as did Pima Indians(Smith et al., 1996). Adams et al. (1995) equatedreservation diets with tryptophan de7ciency. Thefederal government (as required by treaties withmany tribes) supplies government surplus or‘‘commodity’’ food to reservations, and the nutri-tional quality of a commodity food diet may varywidely depending on what is chosen individuallyand can contain high fat, high salt, and low 7ber.The modern item, fry bread, had its origins inoriginal commodity food distributions, when Indianagents often stole everything except lard, 8our,and salt, so fry bread has a cultural meaningrelating to survival (Cajete, 1999) and will not begiven up.

Partial or targeted dietary surveys. These sur-veys can be found in the literature and may beinitiated as a response to a speci7c research projector to a speci7c incident of contamination. Many ofthese studies suggest research needs with respect tolead exposure in Native Americans. For instance,lactose intolerance is widespread among American

Indian adults, which could result in calcium de7-ciency and therefore increased absorption of lead ifexposure were to occur (Goyer, 1997; Crowe andMorgan, 1996). Although a higher milk intake dur-ing pregnancy results in lower lead levels in cordblood (Rothenberg et al., 1996), if the mother is lac-tose intolerant she would ingest less milk duringpregnancy and possibly buy or serve less milk to herchildren. If this same mother has accumulateda higher bone lead level that is mobilized duringpregnancy (Hernandez-Avila et al., 1998; Gulson etal., 1999), the children could be at higher risk. His-torically, lead in bone (Patterson et al., 1991; Erick-son et al., 1991) and teeth (Kuhnlein and Calloway,1977) was much lower than it is now, so there wouldnot have been a lactose intolerance and a cal-cium}lead issue except perhaps in special cases ofuse of lead pigments.

Chan et al. (1995) studied subsistence ingestionrates of seal, beluga, caribou, and other foods, in-cluding organs and animal parts, known to be con-taminated by heavy metals. They found that manyindividuals had high heavy metal intakes, includinglead, and noted that some individuals received muchhigher doses due to overall dietary practices. Manyother studies like this are now appearing in theliterature. These are important because they mayhelp determine whether there is an interaction be-tween nutritional status (calcium and Vitamin D inparticular) and lead absorption. For instance, Nativepopulations from both northern (Haworth and Dill-ing, 1986; Gessner et al., 1997; Waiters et al., 1999)and southern (Brown and Brenton, 1994) regionshave been found to be de7cient in Vitamin D, whichis involved with calcium in lead absorption (Moon,1994; Fullmer, 1997). Because there are genetic in-8uences in lead absorption related to the vitamin Dreceptor gene and other genes (Onalaja and Claudio,2000; Schwartz et al., 2000), and because one of thevariants of the vitamin D receptor protein (Gc locus)is associated with Type 2 diabetes, glucose tolerance,and insulin resistance (Baier et al., 1998; Szathmary1987), there may be a genetic situation regardinginsulin metabolism that affects lead absorption thatdid not reach physiological levels of concern whenlead exposure and/or diabetes were much lower.

Many other reports exist for speci7c foods, mostoften 7sh. Recent attention has centered on omega-3polyunsaturated fatty acids (PUFA). Many medicalstudies have shown bene7cial effects of PUFA, parti-cularly for heart disease. Since 7sh provided (andcontinue to provide) the major protein source forsome tribes (including the Columbia River tribessuch as the Umatilla, Walla Walla, and Cayuse

TABLE 2Additional Potential Sources of Lead Exposure

for Native Americans

Other potential coexposuresto lead Rationale

Older housing Reservation housing is oftenolder and in poorer condition;unknown rates of lead-basedpaints

Lead shot and 7shing weights Poverty may force handmadeuses

Pigments (decorative) Lead- and cinnabar-based pig-ments with dermal absorp-tion and bone storage (Ghaziet al., 1994)

Use of animal bones or bonemeal

Degree of use and degree of leadstorage unknown

Sediment Mining sediments heavily ladenwith lead are moving downthe Columbia River and otherwaterways

Agricultural lead}arsenate Non-point-source runoff fromold orchards

Airborne deposition A primary pathway of exposurefor herbivores (Kalas et al.,2000)

Site-speci7c soil and 7shcontamination

Many mining and other Super-fund sites contain lead; many7sh populations contain lead

Coexposures to otherneurotoxins

Mercury and PCBs in 7sh;un-known cumulative effects

NATIVE AMERICAN DIETS AND EXPOSURE FACTORS 145

tribes) for thousands of years, the relation of tradi-tional diets to modern health is particularly close. Atleast one report showing elevated omega-3 PUFAamong Alaskan Eskimos has been published(Parkinson et al., 1994). It is clear that traditional orsubsistence levels of 7sh consumption are bene7cial,but 7sh are more and more often contaminated.Egeland and Middaugh (1997) discussed ‘‘balancing’’the health bene7ts of eating 7sh contaminated withmercury without considering the cultural import-ance of eating 7sh and this concept frequently ap-pears in 7sh advisories. Tenenbaum (1998) said that‘‘indigenous populations in the Arctic are the mostaffected by contamination of their traditional foodsources2[but] changing to a more modern diet maybe even worse for these people’s health.’’ This is truenot just because the quality of the replacement dietmay be poorer, but also because 7sh may be a cul-tural resource and an essential part of the religion. Ifthe optimization of eating 7sh or not eating 7sh isbased solely on probability of a clinically and statist-ically signi7cant health affect, signi7cant impactsare missed. What part of a culture or religion arepeople supposed to give up to avoid exposure? Immi-grants suffer mental and physical ailments, social iso-lation and the loss of stable religious af7liations thatherald health declines (Bower, 1998), and tribal reser-vations suffer similar conditions on an ongoing basis.

For lead exposure, the diet may not be the onlysource of lead. For Native Americans, other factorsmay also put them at risk of increased exposure orincreased response (Table 2), although systematicstudies have not been done. Health status informa-tion in Native Americans is sparse. For example,there was only a single article indexed in MedLinefrom 1994 to 1998 about blood lead levels in NativeAmericans, Americans Indians, reservations, ortribes, and that article stated that the ‘‘CDC lead-screening questionnaire failed to ef7ciently identifythose children with lead toxicity,’’ referring toa study conducted on the Navajo reservation (Kazal,1997). The only other citation was a case of gasolinesnif7ng. It is known that factors that enhance risk oflead exposure are low SES, old housing,3 and lowdietary intake of calcium, iron, and zinc (Goyer,1996), and each of these conditions is present toa greater or lesser degree on reservations. Otherstudies identify similar risk factors, but have notlooked speci7cally at Native American populations(Kraft and Scheberle, 1995; Pirkle et al., 1998).

3Tribal housing is often older, and the prevalence of lead paintis a concern but is unknown. The EPA has several pilot projectsunderway to determine whether lead paint is a problem on reser-vations (E. Avant, EPA Region 5, personal communication).

RISK CHARACTERIZATION AND RISKMANAGEMENT ISSUES

Risk characterization from our perspective meansmore than estimation of the probability of overthealth effects or the probability of a certain percen-tile of children exceeding a particular blood leadlevel. To us, risk characterization means looking atboth the exposure and the sensitivity (risk"expo-sure]sensitivity) and the risk to the entire lifestyleif places or resources are contaminated. We refer tothis as ‘‘eco-cultural-health’’ risk management. Evenif we consider just the human exposure element,there are broader perspectives that need to be con-sidered (remembering that each sovereign tribalgovernment makes its own health and environ-mental policy decisions).

One issue is the level of protection that is setas the goal or identi7ed as acceptable. Use of

146 HARRIS AND HARPER

dose-based models such as the IEUBK does not ne-cessarily mean that any amount of exposure or en-vironmental degradation is acceptable either as new(permitted) releases, residual (post remediation)contamination, or non-point-source exposure (e.g.,general municipal water and sediment concentra-tions). In other words, a tribe may not agree thatprotecting 95% of children to a blood lead level of10 lg/dl is the correct risk management goal. SinceNHANES III showed that today’s blood levels inclean suburban settings are 2.8 lg/dl (Flegal andSmith, 1995; Brody et al., 1994; MMWR, 2000), thereis no a priori reason why a tribe should accept 5% ofchildren exceeding 10 lg/dl, particularly since thecurrent exposure limit for Pb has no margin of safetyand ‘‘blood lead levels as low as 10 lg/dl can adverse-ly affect the behavior and development of children’’(MMWR, 1997).

Since the EPA has not developed either a Refer-ence Dose (which would include a safety factor) ora cancer slope factor for lead, it cannot be included incumulative risk assessments. In addition, the MCL4

may not be protective enough for tribal children whoare vitamin and mineral (calcium) de7cient. Concen-tration benchmarks and standards were seldom de-veloped with such combinations of risk factors inmind and need to be reevaluated speci7cally fortribal situations. If exposures to other neurotoxins isoccurring, both individual and community impactsmust be evaluated. A unit of selection could also bethe community’s gene pool or neuronal pool. Fur-ther, a neurological de7cit in even one person couldimpair the intergenerational transfer of knowledge,which could cause a cumulative detriment to hun-dreds of people or to the whole tribe.

HUMAN SUBJECTS RESEARCH AND RISKCOMMUNICATION

There are many complex issues regarding thestudy of Native Americans, their cultures and eco-cultural resources, and issues of human sampling.There are issues of intellectual property that extendbeyond the well-known intellectual property rightspertaining to sacred sites or con7dential cultural orreligious practices (all of the information about tra-ditional practices including subsistence foods is theintellectual property of the tribe, and some of it willsimply never be released). Because few tribes haveInstitutional Review Boards that review human sub-jects research, they are generally at a disadvantage

4MCL refers to maximum contaminant level, the term for enfor-ceable limits of individual contaminants in drinking water.

with respect to control over the data, control overhuman biological samples, and so on, regardless ofthe external review that has been done by universityor Indian Health Service IRBs. State departments ofhealth may do studies with no IRB review at all.Tribal research codes are still rare and may or maynot have considered human, ecological, and culturalresearch as a total package. Therefore, there aremany constraints on doing the research to 7ll thesedata gaps and test these hypotheses.

There have been several books and papers pub-lished on cross-cultural counseling and cross-cul-tural nursing and health care provision and a few oncross-cultural risk communication. While the litera-ture on the provision of culturally appropriatehealth care (including native healers along withwestern healers) has grown, the risk communicationliterature has not yet dealt with this issue.

CONCLUSION

Communication of risk management concepts toreduce lead exposure within Native American Tribesrequires a fundamental understanding of the com-munity, resource base, and culture. Often re-searchers lacking this fundamental knowledge willsimply follow the standard protocols and ‘‘check-off ’’lists. Design of the research statement without thisunderstanding may result in overlooking critical cul-tural components of the community. If the keystonecommunity member(s) who know the cultural pro-cess needed for day to day subsistence survival is/areoverlooked, then the evaluation of the pathways toexposure resulting from cultural use of a con-taminated resource may not be re8ected in the riskmanager’s decision process. Evaluation of lead expo-sure must take into account more than simply a sub-urban exposure scenario. The evaluation must alsoconsider unique combinations of factors that affectexposure, bioavailability, and response to the neur-otoxicity and other effects of lead. Even question-naires designed to predict lead exposure usingsurvey techniques may not be suitable for NativeAmerican populations and living situations (Kazal,1997).

This is not simply a communication or study de-sign problem. Indeed, risk communication is onlypart of the solution and can address only those as-pects of the problem that are more westernized (suchas the house paint issue). Risk communication tech-niques such as 7sh advisories can be somewhat ef-fective in reducing consumption of a contaminatedresource (Fitzgerald et al., 1995), but risk commun-ication and risk management must be tailored to be

NATIVE AMERICAN DIETS AND EXPOSURE FACTORS 147

culturally sensitive (Van Oostdam et al., 1999; Har-ris, 2000). Risk management may follow a process ofbalancing costs, bene7ts, and impacts. However, wepropose that instead of dollars as the fulcrum, riskethics becomes the primary driver for balancing cost,bene7ts, and impacts from the perspective of theaffected people. We recommend that this concept bemore fully explored by professional societies andthat fellowships in risk ethics be established.

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