Use Of Hair Research Articles

Human hair shaft proteomic profiling: individual differences, site specificity and cuticle analysis.

Hair from different individuals can be distinguished by physical properties. Although some data exist on other species, examination of the individual molecular differences within the human hair shaft has not been thoroughly investigated. Shotgun proteomic analysis revealed considerable variation in profile among samples from Caucasian, African–American, Kenyan and Korean subjects. Within these ethnic groups, prominent keratin proteins served to distinguish individual profiles. Differences between ethnic groups, less marked, relied to a large extent on levels of keratin associated proteins. In samples from Caucasian subjects, hair shafts from axillary, beard, pubic and scalp regions exhibited distinguishable profiles, with the last being most different from the others. Finally, the profile of isolated hair cuticle cells was distinguished from that of total hair shaft by levels of more than 20 proteins, the majority of which were prominent keratins. The cuticle also exhibited relatively high levels of epidermal transglutaminase (TGM3), accounting for its observed low degree of protein extraction by denaturants. In addition to providing insight into hair structure, present findings may lead to improvements in differentiating hair from various ethnic origins and offer an approach to extending use of hair in crime scene evidence for distinguishing among individuals.

Hair analysis as a useful procedure for detection of vapour exposure to chemical warfare agents: simulation of sulphur mustard with methyl salicylate.

Chemical warfare agents (CWA) are highly toxic compounds which have been produced to kill or hurt people during conflicts or terrorist attacks. Despite the fact that their use is strictly prohibited according to international convention, populations' exposure still recently occurred. Development of markers of exposure to CWA is necessary to distinguish exposed victims from unexposed ones. We present the first study of hair usage as passive sampler to assess contamination by chemicals in vapour form. This work presents more particularly the hair adsorption capacity for methyl salicylate used as a surrogate of the vesicant sulphur mustard. Chemical vapours toxicity through the respiratory route has historically been defined through Haber's law's concentration-time (Ct) product, and vapour exposure of hair to methyl salicylate was conducted with various times or doses of exposure in the range of incapacitating and lethal Ct products corresponding to sulphur mustard. Following exposure, extraction of methyl salicylate from hair was conducted by simple soaking in dichloromethane. Methyl salicylate could be detected on hair for vapour concentration corresponding to about one fifth of the sulphur mustard concentration that would kill 50% of exposed individuals (LCt50). The amount of methyl salicylate recovered from hair increased with time or dose of exposure. It showed a good correlation with the concentration-time product, suggesting that hair could be used like a passive sampler to assess vapour exposure to chemical compounds. It introduces great perspectives concerning the use of hair as a marker of exposure to CWA.

Investigating the Use of Hair to Assess Polybrominated Diphenyl Ether Exposure Retrospectively

Polybrominated diphenyl ethers (PBDEs) are chemicals that are added to a variety of consumer products as flame-retardants and have been classified as emerging endocrine disruptors. They are persistent and have been detected in humans. Previous studies have suggested that hair is a suitable matrix for examining human exposure to organic pollutants such as PBDEs. It is believed that the majority of exposure is from our indoor environment. The aim of this study was to investigate the changes in PBDE patterns and levels along the hair shaft, by using segmental analysis to retrospectively assess long-term exposure over a 1-year period. Questionnaires and hair samples from 65 women were collected at the Hospital for Sick Children, in Toronto, as part of a larger study. To assess long-term stability, hair samples were separated into 4- and 3-cm segments representing a 1-year period. Hair segments were analyzed for levels of 8 PBDE congeners, BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, and BDE-209 on gas chromatography-mass spectrometry (MS). A Friedman test was used to detect the differences in exposure among segments, and factors such as dietary habits, hair care routine, and site of residence were investigated to determine if they might affect hair levels. A significant increase (P < 0.0001) in total PBDEs was seen among segments moving from proximal (root end) to distal along the hair shaft (median in pg/mg): first (33.3), second (43.0), third (61.6), and fourth (75.5) segments. Significantly lower levels of PBDEs were observed in artificially colored hair samples (P = 0.032), and a significant increase in PBDE levels was observed in women who consumed meat on a daily basis as opposed to weekly consumption (P = 0.040). The increase in PBDEs along the hair shaft suggests that hair PBDEs may be influenced by diet and artificial coloring. More work is needed to validate the use of PBDEs in hair as a biomarker of long-term exposure.

Occurrence and levels of polybrominated diphenyl ethers (PBDEs) in house dust and hair samples from Northern Poland; an assessment of human exposure

Polybrominated diphenyl ethers (PBDEs) are among most ubiquitous compounds to be found in indoor environment and ingestion of household dust is considered an important route of exposure to PBDEs, especially in toddlers and young children. The present work reported concentration levels of PBDE congeners (PBDE-28, -47, -99, -100, -153, -154, -183 and -209) in hair and dust samples from selected households from Northern Poland. The concentrations of PBDEs in dust ranged from <MDL to 615ngg−1 while from <MDL to 25ngg−1 in human hair. PBDE-209 was reported the dominating congener. Two separated exposure scenarios (mean and 95th percentile) were used to provide a comprehensive overview of possible risks arising from ingestion of household dust. The estimated exposure to ∑PBDEs via ingestion of household dust varied from 21 to 92ngd−1 in toddlers and from 3.7 to 20ngd−1 in adults. By comparison of correlation between the concentrations of PBDEs in paired hair and dust samples the present work also investigated the possibility of use of hair for reflecting the actual exposure to PBDEs in humans. Finally the possible uncertainties associated with exposure assessment were investigated in the present study.

Genotoxicity among Hairdressers and the Level of Commitment to Occupational Safety Measures at Beauty Salons, in Zagazig City, Egypt

Hairdressers are chronically exposed to several occupational hazards during their work including potentially genotoxic chemicals. Hair dying, hair smoothening and straightening products are hazardous chemicals that affect human health and are frequently used in beauty salons. So, this study aimed to evaluate the genotoxic risk among the studied hairdressers, to estimate the level of p-phenylenediamine (p-PDA) in urine and to assess the degree of adherence of the studied hair- dressers to occupational safety measures at work. A comparative cross sectional study was carried out on 40 hairdressers working in beauty salons in Zagazig city, Egypt and 40 administrative staff at faculty of medicine as a control group. The results of the study revealed a significant increase in mean concentration of urinary p-PDA as well as significant increase in DNA damage assessed by Comet assay in lymphocytes among studied hairdressers than among their controls. Also, there was a statistically significant decrease in adherence to most of the occupational safety precaution measures that should be followed by the studied hairdressers. The significant risk factors of high Comet total mean score among the studied hairdressers were occupational use of hair straightening ≥8 times/week, use of hair dyes at work ≥15 times/week, length of service ≥13 years, negligence of wearing gloves during work, use of bleaching agents ≥12/week and negligence of hand wash after handling chemicals. So, it was concluded that the hairdressers are occupationally exposed to the risk of genotoxic hazards from chemicals frequently used in their work. The lack of commitment to occupational safety measures at beauty salons like wearing gloves during work and hand washing increases the risk of genotoxicity.

Monitoring of Environmental Mercury Exposure Using Hair as Bioindicator and the Study of Potential Factors Affecting on It in Karachi

The World Health Organization (WHO), Environmental Protection Agency (EPA), and International Atomic Energy Agency (IAEA) have recommended the use of hair for worldwide environmental monitoring. Mercury exposure to the inhabitants of Karachi was assessed by using hair as bioindicator. Hair samples of 200 residents of Karachi were collected and analyzed through cold vapor atomic absorption spectroscopy (CVAA) technique for mercury concentration. The effects of age, gender, working status, location, food and smoking habit were investigated. Control region showed a positive correlation between HHg and age of donor while no such correlation was observed for polluted regions. Mercury exposure through cosmetic usage in female was only pronounced in control region. These results indicate that environmental pollution dominates other potential factors. Age and smoking habit were not found to be the influencing factors while an elevated mean level of mercury was noticed for regular fish consumers than rarely fish consumers. 95.33% of the samples contained HHg greater than the permissible level of 2 μg?g?1 set by WHO. An apparently healthy male donor had HHg concentration (28.24 μg?g?1) closer to the high risk concentration of 30 μg?g?1 based on WHO criteria. Whereas, two female donors of the age group of 41-50 years had HHg concentrations (10.82 and 11.84 μg?g?1) higher than the NOAEL (no observed adverse affects level) value (10 μg?g?1) for females which is associated with fetus neurotoxicity. However, no symptoms of mercury toxicity were visible. The results indicate the alarming condition of pollution in the city which should be taken into further consideration.

The Use of Animal Hair in Ceramic Manufacturing at the Tytkesken-2 Neolithic Site, Western Siberia

The comb pottery found at Tytkesken-2 horizons 7, 6, 4A, and 4 reveals traces of animal hair. Hair was used as armature at the shaping stage: it was wound around the body of the vessel to prevent cracking during baking and drying (pastes were prepared without the use of hair). As the Tytkesken-2 ceramics demonstrate, using hair as armature was a local tradition, practiced in some measure from the Early to the Final Neolithic period.

Simultaneous quantification of morphine and cocaine in hair samples from drug addicts by GC‐EI/MS

The development of analytical techniques that enable the use of hair as an alternative matrix for the analysis of drugs of abuse is useful for confirming the exposure in a larger time window (weeks to months, depending on the length of the hair shaft). In the present study a methodology aimed at the simultaneous quantification of cocaine and morphine in human hair was developed and validated. After decontamination, hair samples (20 mg) were incubated with a mixture of methanol/hydrochloric acid (2:1) at 65 °C overnight (~16 h) in order to extract the drugs of the matrix. Purification was performed by solid-phase extraction using mixed-mode extraction cartridges. After derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide, blank, standards and samples were analyzed by gas chromatography/electron impact-mass spectrometry (GC-EI/MS). The method proved to be selective, as there were no interferences of endogenous compounds with the same retention time as cocaine, morphine and ethylmorphine (internal standard). The regression analysis for both analytes showed linearity in the range 0.25-10.00 ng/mg with correlation coefficients ranging from 0.9989 to 0.9991. The coefficients of variation oscillated between 0.83 and 14.60%. The limits of detection were 0.01 and 0.02 ng/mg, and the limits of quantification were 0.03 and 0.06 ng/mg for cocaine and morphine, respectively. The proposed GC-EI/MS method provided an accurate and simple assay with adequate precision and recovery for the quantification of cocaine and morphine in hair samples. The proof of applicability was performed in hair samples obtained from drug addicts enrolled in a Regional Detoxification Treatment Center. The importance of hair samples is highlighted, since positives results were obtained when urine immunoassay analyses were negative.

Human Exposure to Antimony. II. Contents in Some Human Tissues Often Used in Biomonitoring (Hair, Nails, Teeth)

The presence of antimony in the human body is the result of exposure from many different sources, as is the case for any chemical element. The use of hair for diagnosing antimony exposure has become very popular because of the uncomplicated sampling and preservation, but the true utility of such studies remains uncertain. This review presents a critical discussion of the existing literature on antimony concentrations in hair, nails, and teeth, with three main objectives: (a) evaluating published data from the methodological point of view, (b) establishing a range of plausible values for antimony concentrations in these tissues, and (c) assessing statistically based correlations reported in case-control studies. From a methodological standpoint, existing data suffer from the lack of adequate certificate reference materials, low concentrations close to the detection limit of most analytical techniques and data acquisition through applying multielement techniques. These limitations are probably the underlying reason for the high dispersion of the published results and do not make it possible to establish a reliable background value for human hair from healthy, unexposed individuals. However, it is possible to estimate a concentration ceiling at 0.1 μg−1, with a probable value around 0.05 μg−1. Concerning the usefulness of antimony determinations in hair, existing results amply justify its use in occupational studies. On the other hand, the analysis of antimony concentrations in hair as an indicator of human health status does not seem to be based on any scientific evidence. The limited number of studies on human nails and teeth does not allow any conclusions to be drawn.

Hair Covering for Single Women: A New Reading of Mizraḥi Halakhic Rulings

A central feature in the lives of observant Jewish women is hair covering. Head covering is part of the prescribed religious garb of observant Jews, both male and female, but it has been contextualized in different ways on the basis of gender. For women, the usual justification for hair covering has to do with modesty, and it is also taken as a sign that the woman is married. This article deals with a different justification found in a number of responsa, particularly by Mizrahi rabbis, that is not gender-based: yir’at shamayim (fear of God). In this context, I suggest the use of hair covering as a tool for empowerment.

Hair as a biomarker of polybrominated diethyl ethers’ exposure in infants, children and adults

Over the last 20 years hair has moved from being a highly questionable biological matrix to mainstream and acceptable biomarker in forensic sciences where it is primarily used to determine past and present exposure to illicit drugs. In contrast, the use of hair to assess exposure to pesticides and persistent environmental pollutants is still not common. The applicability of this matrix to assess an individual's body burden of chemicals such as polybrominated diethyl ethers (PBDEs) can provide critical insight into current, but also to past exposure levels, which is not possible with more conventional matrices such as blood and urine. Furthermore, as PBDEs cross the placenta and since the hair the fetus is born with begins to grow during the third trimester, this matrix can be used to assess in utero exposure. These features of hair may therefore be used to determine the potential roles of chemicals such as PBDEs in mediating physiological or anatomical abnormalities in infants, children or adults.

Quantification of Metal in the Hair of Copper Miners in Katanga Province, Democratic Republic of Congo

This study aims to demonstrate the exposure of artisanal miners to the contents of mineralised gangue and to assess whether the different workstations and their related operating processes potentiate such exposure. The population sampled (n=100) consisted of artisanal miners operating in the mine of Ruashi, in the south of the Katanga copper belt. We made use of hair as a biomarker and performed our analyses using ICP-MS. According to recommendations from the Agency for Toxic Substances and Disease Registry, we have compared our results to those of an unexposed population living in the same area in order to point out the occupational origins of such exposure. In our hair analysis, we identified and quantified 22 elements. For almost all of these elements, the artisanal miners had much higher values as compared to the control population. In addition, non-diggers had higher levels than diggers for almost all of the elements that could be directly linked to those present in the mineralised gangue. Median values obtained for the artisanal miners were systematically higher than those of the control population, reflecting a higher than normal exposure. Such differences between the two sample populations can only be explained by the occupational (mining) origin of exposure, since the living environment, hair nature, sampling method, and analysis techniques were the same for both populations. Medians within the miner samples showed different exposure profiles for non-diggers versus diggers, resulting from the fact that non-diggers were more exposed to the mineralised gangue. The results attest to the reality and the large extent to which artisanal miners in Katanga Province are exposed to chemical components of mineralised gangue. This exposure is more significant within the workstations related to the raw mineral processing phase as opposed to the extraction phase.

Hair-Snares: A Non-Invasive Method for Monitoring Felid Populations in the Selva Lacandona, Mexico

Non-invasive techniques such as hair snares have been used in conjunction with molecular methods to study species that occur at low densities and have elusive behavior, as an alternative to invasive methods such as trapping and hunting. This study was designed to evaluate the use of hair snares as a non-invasive method for the collection of felid and other mammalian samples in the tropical rainforest of the Selva Lacandona, Chiapas, Mexico. Hair snares were placed along transects in Montes Azules Biosphere Reserve for four months a year in 2005 and 2006. Hairs were selected based on morphological characteristics and identification of species was done based on a diagnostic portion of mtDNA cytochrome b region. A total of 389 hits on 888 hair-snare checks were recorded, representing a capture rate of 43%. The species identified included margay ( Leopardus wiedii, n=2), ocelot ( Leopardus pardalis, n=1), jaguarundi ( Puma yagouaroundi, n=1), gray fox ( Urocyon cinereoargenteus, n=1), tayra ( Eira barbara, n=3), coati ( Nasua narica, n=1), four-eyed opossum ( Metachirus nudicaudatus, n=6), and common opossum ( Didelphis marsupialis, n=16). The present study is the first to report the successful collection of hair samples from jaguarundi and margay in the wild and hair samples from ocelots in tropical areas. The deficit of information on carnivore populations in tropical rainforests is due mainly to the lack of appropriate methodologies that are reliable and cost-effective. This study supports the assumption that hair-snaring is viable and cost-effective in ecosystems such as the Selva Lacandona, particularly when monitoring carnivore populations that have wide geographic distributions and low densities.

A screening of persistent organohalogenated contaminants in hair of East Greenland polar bears

In this pilot study, we report on levels of persistent organohalogenated contaminants (OHCs) in hair of polar bears ( Ursus maritimus) from East Greenland sampled between 1999 and 2001. To our knowledge, this is the first study on the validation of polar bear hair as a non-invasive matrix representative of concentrations and profiles in internal organs and blood plasma. Because of low sample weights (13–140 mg), only major bioaccumulative OHCs were detected above the limit of quantification: five polychlorinated biphenyl (PCB) congeners (CB 99, 138, 153, 170 and 180), one polybrominated diphenyl ether (PBDE) congener (BDE 47), oxychlordane, trans-nonachlor and β-hexachlorocyclohexane. The PCB profile in hair was similar to that of internal tissues (i.e. adipose, liver, brain and blood), with CB 153 and 180 as the major congeners in all matrices. A gender difference was found for concentrations in hair relative to concentrations in internal tissues. Females (n = 6) were found to display negative correlations, while males (n = 5) showed positive correlations, although p-values were not found significant. These negative correlations in females may reflect seasonal OHC mobilisation from periphery adipose tissue due to, for example, lactation and fasting. The lack of significance in most correlations may be due to small sample sizes and seasonal variability of concentrations in soft tissues. Further research with larger sample weights and sizes is therefore necessary to draw more definitive conclusions on the usefulness of hair for biomonitoring OHCs in polar bears and other fur mammals.

Hair care practices and their association with scalp and hair disorders in African American girls

Few studies have extensively examined the prevalence of hair care practices and their association with scalp and hair conditions in African American girls. We sought to determine the prevalence of hair care practices and their association with traction alopecia, seborrheic dermatitis (SD), and tinea capitis (TC). A questionnaire was administered to caregivers of African American girls aged 1 to 15 years. Multivariate analyses were performed to determine the association of hair care practices with reported disorders. A total of 201 surveys were completed from dermatology (n= 98) and nondermatology (n= 103) clinics. Mean patient age was 9.8± 4.4 years. Essentially all respondents reported use of hair oils/grease (99%). Ponytails, braids, and cornrows were worn by 81%, 67%, and 49% of girls, respectively, within the past 12 months. In all, 61% reported hair washing every 2 weeks; 80% used hot combs; and 42% used chemical relaxers. Cornrows were significantly related to traction alopecia among respondents from nondermatology clinics only: adjusted odds ratio= 5.79 (95% CI 1.35-24.8, P= .018). Hair extensions and infrequent hair oil use were significantly related to SD: adjusted odds ratio= 2.37 (95% CI 1.03-5.47, P= .04) and 3.69 (95% CI 1.07-12.7, P= .039), respectively. No significant associations were observed for TC. Small sample size and disorders reported by caregivers were limitations. Certain hair care practices were strongly associated with development of traction alopecia and SD. No association was found between hair washing frequency and SD or TC, or between hair grease use and TC. These results can be used to inform practitioners, advise parents, and adapt treatment regimens to accommodate cultural preferences.

Accumulation of background levels of persistent organochlorine and organobromine pollutants through the soil–earthworm–hedgehog food chain

The bioaccumulation of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and DDT and metabolites, was investigated in the soil–earthworm–hedgehog food chain. Concentrations of selected POPs were measured in soil and earthworms collected in grassland and open woodland and in hair and blood of hedgehogs foraging in two parks containing these habitats. Despite background concentrations in soil (ranging from 1.3 to 9.3 ng/g for DDTs, 2.3 to 6.5 ng/g for PCBs and 0.08 to 0.20 ng/g for PBDEs), biota-soil accumulation factors (BSAFs) indicated that earthworms accumulated POPs (0.48–1.70 for DDTs, 1.09–2.76 for PCBs and 1.99–5.67 for PBDEs) and that animals feeding on earthworms are potentially exposed to higher concentrations of pollutants. BSAFs decreased with increasing soil concentrations for the three groups of compounds, suggesting that steady-state equilibrium was not reached in soil or earthworms. Positive, but low, log-linear relationships were found for DDT ( r 2 = 0.23, p < 0.05 for Brasschaat and r 2 = 0.63, p < 0.01 for Hoboken) and PCB ( r 2 = 0.13, p < 0.05 for both parks) concentrations between soil and earthworms. In order to relate earthworm to hedgehog POP concentrations, the foraging behavior of each individual was taken into account. The use of hair as a potential biomonitoring tissue in exposure and risk assessment of POPs was evaluated by examining the relationship between PCB and p,p′-DDE levels in hedgehogs' hair and blood. Contaminant profiles were used to gain insight into biotransformation of the studied compounds in each step of the investigated food chain and in the blood of hedgehogs, as well as the consequences thereof for their incorporation in hair. The absence of a discernable relationship between POP concentrations in earthworms and hair is possible due to variation in individual foraging behavior and POP uptake. Our results suggest that POPs in tissues should be measured from an adequate number of individuals per population instead of relying on indirect estimates from levels in soil or prey items.

The use of hair as a toxicological tool in DFC casework

When drugging related offences are cited, most people think of sexual assault. However, the law covers any crime committed whilst the complainant is under the influence of alcohol or drugs, i.e., the use of a drug to modify a person's behaviour for criminal gain. The case types encountered include robbery, blackmail and of course sexual offences. Hair analysis for drugs is now well established in Forensic Toxicology. Its use as an analytical tool in workplace testing, post-mortem toxicology and criminal cases is expanding both in the U.K. and worldwide, and it is now widely accepted as an alternative or complimentary matrix for these cases. This paper will provide a brief overview of hair testing in cases of Drug Facilitated Crime stressing the importance of timely sample collection. Its usefulness in cases of this type will be highlighted through case examples.

The use of hair as an indicator of occupational 14C contamination

This paper presents a study in which the specific activity of (14)C in hair has been investigated as an easily determined bio-indicator of the integrated (14)C exposure (over several months). The study includes 28 Swedish workers handling (14)C-labelled compounds, or working in a (14)C-enriched environment. Hair samples from personnel at a Swedish nuclear power plant showed very low levels of (14)C contamination, if any. In contrast, personnel at the investigated research departments showed (14)C levels in hair of up to 60% above the natural specific activity of (14)C. Much higher levels, up to 80 times the natural specific activity of (14)C, were found in hair from individuals working at a pharmaceutical research laboratory. This contamination was, however, not solely an internal contamination. There were indications that most of the (14)C in the hair originated from airborne (14)C-compounds, which were adsorbed onto the hair. The difficulties in removing this external (14)C contamination prior to analysis are discussed, as are the possibilities of using accelerator mass spectrometry to analyse various types of samples for retrospective dose assessment.

Traceability of sulfonamide antibiotic treatment by immunochemical analysis of farm animal hair samples

The use of hair to trace use of unauthorized substances, therapeutic agents, or their misuse is becoming very attractive since residues can be detected for a long time after treatment. For this purpose, an indirect enzyme-linked immunosorbent assay (ELISA) has been evaluated for its capability to trace sulfonamide antibiotic treatment by analyzing cattle and pig hair samples. Pigmented and nonpigmented hair samples from control and sulfamethazine (SMZ)-treated pigs and calves were collected, extracted under different alkaline conditions, and analyzed by ELISA after just diluting the extracts with the assay buffer. Data analysis following the European recommendations for screening methods demonstrates that the ELISA can detect SMZ in hair samples with a limit of detection (90% of the zero dose (IC(90))) between 30 and 75 ng g(-1). The same samples have been analyzed by HPLC after a dual solid-phase extraction. The ELISA results matched very well those obtained by the chromatographic method, demonstrating that the immunochemical method can be used as a screening tool to trace animal treatments. Between the benefits of this method are the possibility to directly analyze hair extracts with sufficient detectability and its high-throughput capability. Preliminary validation data are reported using an experimental approach inspired on the Commission Decision 2002/657/EC criteria for screening methods.

Assessment of hair and bone accumulation of beryllium by mice exposed to contaminated dusts

This study looks at the accumulation of Be in the hair and bones of mice to understand both the use of hair as a bioindicator of exposure to Be and accumulation in bones as a means to evaluate the translocation of Be. We exposed two groups of mice (C3H/HeJ) to 250 microg m(-3) of two different particles sizes of Be metal (fine and intermediate; Be-F and Be-I) during 3 weeks of nose-only inhalation exposure. A control group was exposed to HEPA-filtered air. Mice were sacrificed either 1 or 3 weeks after the end of exposure. Mice were shaved and the bones were extracted. For washed hair, the results of mice sacrificed one week after the end of exposure were 8.3 + or - 1.4 microg kg(-1) hair for the control group, 114 + or - 42 microg kg(-1 )hair for the Be-I group, and 159 + or - 65 microg kg(-1) hair for the Be-F group. Results for Be-F mice sacrificed 3 weeks after the end of exposure showed an average Be concentration in washed hair of 419 + or - 100 microg kg(-1), thus suggesting that excretion of Be in hair increases with time. Be concentration in bones was 6 + or - 3 microg kg(-1) dry bone tissues for the control group, compared with 24 + or - 7 microg kg(-1) for Be-I and 34 + or - 6 or 43 + or - 8 microg kg(-1) for Be-F in mice sacrificed 1 or 3 weeks after the end of exposure. These results demonstrate the potential of using hair and bone as bioindicators of Be exposure.