Use Of Hair Research Articles

Use of Hair as Matrix for Trace Elements Biomonitoring in Cattle and Roe Deer Sharing Pastures in Northern Italy.

Intensive cattle breeding's environmental challenges are prompting shifts to extensive, pasture-based systems, influencing nutrient and pollutant uptake. PTEs are essential and non-essential elements, regularly found in the environment and organisms, and in which unbalances lead to health issues. Hair analysis, a non-invasive method, provides retrospective PTE exposure evaluation. This study aims to understand exposure and species-specific accumulation patterns of PTEs in cattle and roe deer sharing pastures in Northern Italy using the hair analysis. Aluminum, As, Cd, Cr, Ni, Pb, Cu, Mg, Fe, and Zn were quantified through the use of ICP-OES. Findings show As levels significantly higher in roe deer due to their selective feeding, while Cd and Pb levels align with other studies. Essential elements like Cu, Fe, and Zn are lower in cattle, possibly due to diet differences. Higher Cr and Ni levels in cattle suggest contamination or physiological differences in accumulation patterns. In conclusion, hair analysis is valuable for monitoring environmental PTE exposure, highlighting significant interspecies differences and the potential of both animals as bioindicators in shared grazing areas.

Associations between use of chemical hair products and epigenetic age: Findings from the Sister Study

Background: Hair products may be a source of harmful chemicals and have been linked to age-related health outcomes. We investigated whether the use of hair products is related to epigenetic age in a sample of Black (both Hispanic and non-Hispanic) and non-Hispanic White women. Methods: In a subset of 4358 participants aged 35–74 years from the Sister Study, we estimated cross-sectional associations between self-reported use of four chemical hair products (permanent dye, semipermanent dye, straighteners/relaxers, and hair permanents/body waves) in the year before enrollment (2003–2009) and three DNA methylation-based measures of epigenetic age (DunedinPACE, GrimAge age acceleration [GrimAgeAccel], and PhenoAge age acceleration [PhenoAgeAccel]) using survey-weighted multivariable linear regressions. Associations were estimated both overall and by self-identified race and ethnicity, adjusting for chronological age, socioeconomic and lifestyle factors, body mass index, menopausal status, and DNA methylation platform. Results: Associations between the use of hair products and the three epigenetic age measures were largely null. Use of hair permanents/body waves was modestly associated with higher DunedinPACE among all participants (β ever-never = 0.010; 95% confidence interval [CI] = 0.001, 0.019) and with lower PhenoAgeAccel among Black women (β ever-never = −1.53; 95% CI = −2.84, −0.21). Conclusion: In this US-based study, we found little evidence of associations between chemical hair product use and epigenetic age in Black and non-Hispanic White women. Observed associations were modest and largely not supported by dose–response relationships or were inconsistent across epigenetic age measures. Previously observed associations between chemical hair product use and aging-related health outcomes may not be explained by the biological aging pathways captured by DunedinPACE, GrimAgeAccel, or PhenoAgeAccel. Alternative biological pathways are worth investigating in racially diverse samples.

Hair product use and urinary biomarker concentrations of non-persistent endocrine disrupting chemicals among reproductive-aged Black women

BackgroundStudies have shown an association between hair product use and adverse health outcomes. Scientists have hypothesized that exposure to endocrine-disrupting chemicals (EDCs) drives these associations, but few studies have directly evaluated associations between hair product use and biomarkers of EDCs. Even more limited are studies of Black women, who frequently use EDC-containing products (e.g., hair relaxers). ObjectiveWe estimated associations between hair product use and EDC biomarker concentrations. MethodsWe leveraged cross-sectional data from the Study of Environment, Lifestyle, and Fibroids, a cohort of females aged 23–34 years who self-identified as Black/African American from the Detroit-metropolitan area (USA; n = 425). On structured questionnaires, participants reported their past 24-h and past 12-month use of hair products, including relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food. We quantified urinary concentrations of 19 phthalate/phthalate alternative metabolites, 7 phenols, and 4 parabens using high performance liquid chromatography isotope dilution tandem mass spectrometry. EDC biomarker concentrations were creatinine-adjusted and natural log-transformed. We used multivariable linear regression to estimate mean percent differences in EDC biomarker concentrations and 95% confidence intervals (CIs) associated with hair product use, adjusting for sociodemographic confounders. ResultsHair product use was associated with greater concentrations of multiple EDC biomarkers. Notably, use of hair products in the previous 24 h (compared with non-use) was associated with 16.2% (95% CI = 0.7%, 35.9%), 35.0% (95% CI = 2.6%, 77.6%), and 32.3% (95% CI = 8.8%, 92.0%) higher concentrations of mono-isobutyl phthalate, methyl paraben, and ethyl paraben, respectively. Use of hair relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food in the past 12 months was also associated with higher concentrations of multiple phthalate, phenol, and paraben biomarkers. ConclusionHair product use was associated with higher biomarker concentrations of multiple phthalates, phenols, and parabens. These findings suggest that hair products are potentially important exposure sources for hormonally-active chemicals among Black women.

Abstract PO2-13-09: Delayed alopecia among breast cancer survivors

Abstract Background: Retrospective studies suggest that breast cancer survivors report treatment-associated hair loss or thinning years after their initial diagnosis. This study investigates patient perceptions of alopecia persisting 6 years after the diagnosis of breast cancer. Methods: Breast cancer survivors who had signed informed consent for participation in a prospective longitudinal cohort study, the Mayo Clinic Breast Disease Registry (MCBDR), after diagnosis of breast cancer approximately six years prior, were mailed a survey. This survey asked about degree of bother from hair thinning and hair loss on a scale from 0 “not at all” to 4 “extremely” and about use of hair thickening/regrowth products. PROMIS-10 project scales assessed global mental health (5: worst mental health, 20: best mental health). Data were analyzed using descriptive statistics. Results: 969/1476 participants responded (response rate 65.7%); 819 participants were available for analysis. Participant median age was 65.7 years (range 34 -100 years). 604 (73%) had been diagnosed with stage I-II breast cancer, 248 (30%) had received chemotherapy (+/- endocrine therapy), 365 (45%) had received only endocrine therapy, and 206 (25%) had received neither. Nearly half (381, 47%) reported hair loss and over half (468, 57%) reported hair thinning. 155 (19%) used hair regrowth products. Amongst the 526 who were 55 years and older, 270 (51%) reported hair loss and 323 (61%) hair thinning; 111 (38%) of the 291 women under 55 years reported hair loss and 145 (50%) hair thinning. Twenty-eight percent of chemotherapy recipients, 18% of patients who did not receive chemotherapy but received endocrine therapy, and 14% of patients who had received neither reported continued difficulty with moderate to extreme hair loss. Moderate to extreme bother from hair thinning was reported by 34% of chemotherapy recipients, 22% of endocrine therapy-only recipients, and 18% of those who had received neither. See the table for associations between mental health scores and hair loss/thinning. Use of hair growth products was reported by 29% of chemotherapy recipients, 14% of endocrine therapy-only recipients, and 15% of those who had received neither oncologic therapy. Conclusions: Hair loss and thinning are frequently reported as persistently bothersome symptoms from breast cancer survivors. Future investigations into the incidence, predictors, and treatment of chemotherapy and endocrine therapy-associated alopecia are needed. Global mental health scores on PROMIS scale for hair loss and hair thinning Citation Format: Sarah Premji, Kathryn Ruddy, Nicole Larson, Charles Loprinzi, Brittany Dulmage, Maryam Lustberg, Fergus Couch, Janet Olson, Elizabeth Cathcart-Rake. Delayed alopecia among breast cancer survivors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-13-09.

Characterization of organic contaminants in hair for biomonitoring purposes

Biological monitoring is one way to assess human exposure to contaminants. Blood and urine are often used as biological matrices, but hair is an innovative and effective tool for quantifying more biomarkers over a wider exposure window. In order to improve the use of hair in exposure assessment, this article identifies relevant compounds in the literature to investigate hair contamination. Statistical analysis was performed to correlate the physical-chemical properties of the relevant compounds and their concentration levels in hair. Phthalates, pyrethroids and organophosphate flame retardants were chosen for further study of the interpretation of hair measurements for exposure assessment. No significant correlation was found between the average concentration levels in the literature and the physical-chemical properties of the selected compounds. This work also explores the properties of hair and the analytical process that may impact the quantification of organic contaminants in hair. The sample preparation method (sampling, storage, washing) were also studied and adaptations were suggested to improve the existing methods.

Co-occurrence of tetrabromobisphenol a and debromination products in human hair across China: Implications for exposure sources and health effects on metabolic syndrome

The large usage of Tetrabromobisphenol A (TBBPA) in consumer products leads to ubiquitous distribution globally, however, studies on the occurrence of their debromination compounds were rather scarce. Also, though many studies illustrate the effectiveness of hair analysis to assess human exposure to organic pollutants, evidence on the associations with health implications is still fairly limited. Herein, 598 participants from across China were employed to investigate chronic, low-level exposure to TBBPA and debromination products by hair analysis. The geomean concentrations of TBBPA, 2,2′,6-tribromobisphenol A (Tri-BBPA), 2,2′- and 2,6-dibromobisphenol A (Di-BBPA), and 2-monobromobisphenol A (Mo-BBPA) were 1.07, 0.145, 0.135, and 0.894 ng/g, respectively, indicating nonnegligible health risks of debromination products. Hair analyte levels correlated with population age and population density among sampling regions. Sexual- and spatial-variations were observed with higher concentrations in females and in E-waste recycling sites. Logistic regression models showed that TBBPA exposure (adjusted odds ratio (OR): 1.02, 95 % confidential interval (CI): 1.01–1.05) was positively associated with risk of metabolic syndrome by adjusting for various covariates. These findings imply usefulness of hair as an alternative biomonitoring tool to assess human exposure to TBBPA and relative health effects, which highlights public concerns on co-exposure to these chemicals.

Untargeted hair lipidomics: comprehensive evaluation of the hair-specific lipid signature and considerations for retrospective analysis.

Lipidomics investigates the composition and function of lipids, typically employing blood or tissue samples as the primary study matrices. Hair has recently emerged as a potential complementary sample type to identify biomarkers in early disease stages and retrospectively document an individual's metabolic status due to its long detection window of up to several months prior to the time of sampling. However, the limited coverage of lipid profiling presented in previous studies has hindered its exploitation. This study aimed to evaluate the lipid coverage of hair using an untargeted liquid chromatography-high-resolution mass spectrometry lipidomics platform. Two distinct three-step exhaustive extraction experiments were performed using a hair metabolomics one-phase extraction technique that has been recently optimized, and the two-phase Folch extraction method which is recognized as the gold standard for lipid extraction in biological matrices. The applied lipidomics workflow improved hair lipid coverage, as only 99 species could be annotated using the one-phase extraction method, while 297 lipid species across six categories were annotated with the Folch method. Several lipids in hair were reported for the first time, including N-acyl amino acids, diradylglycerols, and coenzyme Q10. The study suggests that hair lipids are not solely derived from de novo synthesis in hair, but are also incorporated from sebum and blood, making hair a valuable matrix for clinical, forensic, and dermatological research. The improved understanding of the lipid composition and analytical considerations for retrospective analysis offers valuable insights to contextualize untargeted hair lipidomic analysis and facilitate the use of hair in translational studies.

Risk Factors Affecting Khalitya (Hair Fall) As Per Deha Prakruti- A Case Control Study Among Adults

Introduction- Ayurveda is the system of medicine for the concept of diseases and health. It is based on concept of Dosha, Dhatu and Mala.As we are following of western life style and food habits blindly, the equilibrium state of Doshas is rapidly disturbing and thus results in shortening of average life expectancy and also now prone towards the Khalitya (hair fall) in early age. Aim & Objectives- Aim- To assess risk factors associated with the Khalitya (Hair fall) in relation to different Deha Prakriti. Objectives- To define level of Khalitya (hair fall) in different Deha Prakriti with the use of hair pull test. To assess the effect of aharaj and viharaj factors in causing Khalitya. Material and Methods- Study design – It is an observational case control study. Male adults of age group between 20 to 50 years were selected. Convenient sampling was used. Cases (50) and controls (50) were selected in 1: 1 proportion. Results and Discussion- Age factor play an important role in Khalitya (p = 0.0365); as age increases the possibility of hair fall also increases. It is well known that, as the level of stress and anger increases, the propensity to develop Vata and Pitta also increases and thereby causes to hair fall. Conclusions- Age is the significant risk factor in causing Khalitya (hair fall); as age increases, there is increased tendency to have hair fall and thus in long run, this will contribute to increased proportion of male pattern baldness among adults.

Long-term monitoring of clodronate in equine hair using liquid chromatography-tandem mass spectrometry

Given the potential for long-term inhibition of bone remodeling/healing and detrimental effects to horses in training, bisphosphonates are tightly regulated in horseracing. Hair has proven to be an effective matrix for detection of drug administration to horses and has been particularly effective in detecting drugs for a long period of time post administration. Thus, hair may prove to be a useful matrix for detection of administration of this class of drugs. The objective of the current study was to develop an assay and assess the usefulness of hair as a matrix for long-term detection of clodronate to horses. Seven horses received a single intramuscular administration of 1.8 mg/kg clodronate. Hair samples were collected prior to and up to 6 months post administration. A liquid chromatography-tandem mass spectrometry method was developed and concentrations of clodronate measured in hair samples. The drug was first detected on day 7 in 4/7 horses, and on days 14, 28 and 35 in the remaining three horses. In 4/7 horses, clodronate was still detectable 6 months post administration. Results of this study demonstrate that, although there was significant inter-individual variability in detection times (63 to 180 days) and several intermediate times where the drug could not be detected but was subsequently detected in later timepoints, clodronate administration was detectable in hair for a prolonged period in most of the horses (4/7) studied.

Comparison of two methods for the extraction of ethylglucuronide from hair.

The aim was the comparison between the Society of Hair Testing (SoHT) consensus for the use of alcohol markers which powdering hair for the extraction of ethylglucuronide (EtG) in water and extraction using the patented M3 Reagent Test kit on cut hair. Hair samples were cut into small segments and washed twice with methanol and diethyl ether. The SoHT-Consensus entails the extraction of pulverised hair in water. This is obtained by incubation of 25 mg of hair at room temperature overnight and 2 h sonication, even if the overnight incubation is not mandatory. The M3 method entails incubation of 25 mg of cut hair with the M3-Reagent at 100°C for 60 min. After centrifugation, the supernatant is injected into a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Samples (191) were collected in the APSS laboratory in Trento, Italy, between 2021 and 2022. The limit of quantification (LOQ) was set at 5pg/mg for the pulverised and M3-Reagent methods. Assays showed good linearity above the range of LOQ-300 pg/mg. Precision (within 20%) values were also obtained using both methods. In the Passing-Bablock linear regression, the final regression curve between M3 (y) and the pulverising method (x) showed good agreement; the Bland-Altman analysis did not show any significant bias between the two methods. The M3-Reagent method, due to cut hair use, is easy to perform, saves time and allows for a smaller sample quantity loss with use of nondisposable grinding jars for the ball mill to obtain the extraction of EtG.

The challenge of assessing exposure to fast-elimination endocrine disruptors: When collecting? Which matrix? How many samples?

Background and Aim The assessment of human exposure to fast-elimination endocrine disruptors (FEED) such as phthalates, bisphenols or pesticides is usually based on urinary biomarkers. The variability of biomarkers concentration, due to rapid elimination from the body combined with frequent exposure is however pointed out as a major limitation to obtain reliable information. Collecting samples at specific times of the day, or increasing the number of samples have been suggested to improve the quality of exposure assessment. In parallel, the use of hair, less sensitive to short-term variations in the exposure, have also been proposed as a possible alternative. No consensus has however been reached yet on these points and providing a reliable information on exposure to FEED remains highly challenging. Methods Urine and hair samples were repeatedly collected from 16 volunteers over a 6 months follow-up. 92 hair samples and 805 urines samples were collected and analyzed for 16 phthalate metabolites, 4 bisphenols and 8 pesticides metabolites. Results 21 biomarkers were more frequently detected in urine, 6 in hair, and 1 was equivalent. Biomarkers were much more variable in urine, with intraclass correlation coefficients (ICC) ranging from 0.09 to 0.51, compared to 0.1 to 0.8 in hair. No preferred moment between first urine of the day, morning, afternoon and evening could be identified for urine collection. Algorithms demonstrated that between 10 (for monobenzyl phthalate) and 31 (for bisphenol S) samples were necessary to correctly classify 87.5% of the subjects into quartiles according to their level of exposure. Conclusions The study illustrates the complexity of assessing exposure to FEED and documents the respective advantages and limitations of urine and hair. These results provide new insights in exposure assessment based on biological matrices and will help to better design future biomonitoring strategies. Keywords: Exposure Biomarkers, Endocrine disruptors, Exposure assessment, Phthalates, Pesticides

Evaluation of hair analysis for determination of trace mineral status and exposure to toxic heavy metals in horses in the Netherlands.

Analysis of hair to gain insight into the trace mineral status and exposure to toxic heavy metals of horses is attractive because hair is an easily accessible sample material. To investigate the potential value of hair analysis in horses for determination of trace mineral and heavy metal concentrations, we analyzed mane hair and liver samples from 62 horses presented for slaughter at a facility in the Netherlands that receives horses from all regions of the country. Hair samples were cleaned in warm water. After acid digestion of hair and liver specimens, we quantified, with inductively coupled plasma-mass spectrometry, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc in the digests. Based on Pearson product moment correlations, we found no statistically significant correlations between concentrations of trace minerals in liver and hair, with the exception of a slight correlation for copper that was too weak to be of clinical relevance. Our results do not support the use of hair to determine trace mineral status and exposure to toxic heavy metals in the horse under field conditions.

Evaluating the use of hair as a non-invasive indicator of trace mineral status in woodland caribou (Rangifer tarandus caribou).

Trace mineral imbalances can have significant effects on animal health, reproductive success, and survival. Monitoring their status in wildlife populations is, therefore, important for management and conservation. Typically, livers and kidneys are sampled to measure mineral status, but biopsies and lethal-sampling are not always possible, particularly for Species at Risk. We aimed to: 1) determine baseline mineral levels in Northern Mountain caribou (Rangifer tarandus caribou; Gmelin, 1788) in northwestern British Columbia, Canada, and 2) determine if hair can be used as an effective indicator of caribou mineral status by evaluating associations between hair and organ mineral concentrations. Hair, liver, and kidney samples from adult male caribou (nHair = 31; nLiver, nKidney = 43) were collected by guide-outfitters in 2016–2018 hunting seasons. Trace minerals and heavy metals were quantified using inductively-coupled plasma mass spectrometry, and organ and hair concentrations of same individuals were compared. Some organ mineral concentrations differed from other caribou populations, though no clinical deficiency or toxicity symptoms were reported in our population. Significant correlations were found between liver and hair selenium (rho = 0.66, p<0.05), kidney and hair cobalt (rho = 0.51, p<0.05), and liver and hair molybdenum (rho = 0.37, p<0.10). These findings suggest that hair trace mineral assessment may be used as a non-invasive and easily-accessible way to monitor caribou selenium, cobalt, and molybdenum status, and may be a valuable tool to help assess overall caribou health.

Detection of the Synthetic Cannabinoids AB-CHMINACA, ADB-CHMINACA, MDMB-CHMICA, and 5F-MDMB-PINACA in Biological Matrices: A Systematic Review.

Simple SummarySynthetic cannabinoids were originally developed for scientific research and potential therapeutic agents. However, clandestine laboratories synthesize them and circumvent legal barriers by falsely marketing them as incense or herbal products. They have serious adverse effects, and new derivatives are continuously found in the market, making their detection difficult due to the lack of comparative standards. Human matrices are used to identify the type of synthetic cannabinoid and the time of its consumption. This review discusses the use of hair, oral fluid, blood, and urine in the detection and quantification of some of the major synthetic cannabinoids. Based on the results, some recommendations can be followed, for example, the use of hair to detect chronic and retrospective consumption (although sensitive to external contamination) and oral fluid or blood for the simultaneous detection of the parent compounds and their metabolites. If longer detection times than blood or oral fluid are needed, urine is the matrix of choice, although its pH may intervene in the analysis. This work highlights the use of new techniques, such as high-resolution mass spectrometry, to avoid the use of previous standards and to monitor new trends in the drug market.New synthetic cannabinoids (SCs) are emerging rapidly and continuously. Biological matrices are key for their precise detection to link toxicity and symptoms to each compound and concentration and ascertain consumption trends. The objective of this study was to determine the best human biological matrices to detect the risk-assessed compounds provided by The European Monitoring Centre for Drugs and Drug Addiction: AB-CHMINACA, ADB-CHMNACA, MDMB-CHMICA, and 5F-MDMB-PINACA. We carried out a systematic review covering 2015 up to the present date, including original articles assessing detection in antemortem human biological matrices with detailed validation information of the technique. In oral fluid and blood, SC parent compounds were found in oral fluid and blood at low concentrations and usually with other substances; thus, the correlation between SCs concentrations and severity of symptoms could rarely be established. When hair is used as the biological matrix, there are difficulties in excluding passive contamination when evaluating chronic consumption. Detection of metabolites in urine is complex because it requires prior identification studies. LC-MS/MS assays were the most widely used approaches for the selective identification of SCs, although the lack of standard references and the need for revalidation with the continuous emergence of new SCs are limiting factors of this technique. A potential solution is high-resolution mass spectrometry screening, which allows for non-targeted detection and retrospective data interrogation.

Occupational differences in personal care product use and urinary concentration of endocrine disrupting chemicals by gender.

In most societies, women and men systematically differ in consumption of cosmetics and household products, which are interlinked with gendered norms and occupational segregation. We investigated the differences in personal care product (PCP) use and exposure to endocrine disrupting chemicals (EDCs) based on occupation and gender. We utilized data from the first to third Korean National Environmental Health Survey analyzing 9218 participants aged 20-59 years engaged in their current occupation for ≥3 months. Frequent PCP use (≥once/week) and exposure to EDCs were analyzed by gender and occupation. We used least-square geometric means (LSGMs) of urinary concentrations of the five EDCs adjusted for covariates. Manual occupation was most common in men and no paid occupation was most frequent in women. In general, clerical, service, and sales workers showed the highest prevalence of frequent use of hair and body products. Women used body and makeup products more frequently than men. For all five EDCs, similarly, women showed higher urinary levels in all occupation groups. When stratified by gender, the differences in urinary concentration of EDCs across occupation groups were not observed in men. Among women, clerical, service, and sales workers showed higher bisphenol A (BPA) and mono-n-butyl phthalate (MnBP) levels than manual workers. Differentials in exposure to EDCs by occupation groups were not evident for men. Given the higher urinary concentration of EDCs in women compared to men, interventions to reduce the exposure to EDCs would need to focus on women, especially in clerical, service, and sales occupations.

Noninvasive sampling of mountain lion hair using modified foothold traps

AbstractAlthough genetic analysis is an increasingly affordable option for wildlife studies, obtaining high‐quality samples from cryptic carnivores remains difficult. To address this, we modified and tested 20.3‐cm (8‐inch) foot snares in unbaited trail sets for noninvasive collection of hair samples from mountain lions (Puma concolor). We deployed 22 hair traps in the Black Range in southern New Mexico from May to November 2017, monitored by remote cameras, at 66 locations for 1,618 trap nights ( = 24.5 nights, SD = 7.2 nights). Photos indicated 20 instances of mountain lions passing within 2 m of a hair trap and we collected 7 mountain lion hair samples, which averaged &gt;20 hairs/sample. All samples contained hair with visible roots and were identifiable to species; 6 of the 7 (85.7%) yielded sufficient DNA for individual identification. We attributed failure to obtain samples to 3 primary causes: individual trap saturation (2 instances), trap failure (2 instances), and non‐trigger events (9 instances). Black bears (Ursus americanus) and heavy rains were the primary sources of disturbance to hair trap sets, contributing to individual trap saturation and trap failure. We speculate that low trigger rates were associated with pan tension having been set too high in the first month of the study, as well as disturbance of hair traps or leading foot placements by nontarget species. We discuss strategies to increase hair sample collection rates, including seasonal use of hair traps, more selective placement on the landscape, and altering physical attributes of the hair traps. The quality of hair samples we collected and subsequent amplification rates indicated that, along with proper deployment strategies, hair traps are a viable tool for noninvasively collecting genetic material for individual identification of mountain lions and other elusive species.

Persistent organic pollutants on human and sheep hair and comparison with POPs in indoor and outdoor air

This study compared the concentration of persistent organic pollutants (POPs) in air derived from polyurethane-based passive samplers to those of hair samples collected from humans and sheep. Human scalp hair samples were obtained from 24 healthy individuals and ten sheep (Ovis aries) during indoor and outdoor polyurethane foam plug ambient sampling. The samples were analyzed for polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PBDEs). ∑PBDE concentrations ranged 0.6-50 ng·g-1 (mean, 18.6 ± 13 ng·g-1) for humans and 0.6-1.4 ng·g-1 (mean, 1.1 ± 0.25 ng·g-1) for sheep. The ∑PAH concentrations were log-normally distributed in human hair ranging 98-2529 ng·g-1 (mean, 460 ± 538 ng·g-1), whereas concentrations for sheep hair samples ranged 168-526 ng·g-1 (mean, 334 ± 117 ng·g-1). Strong correlations (P-values &lt; 0.01) were found between concentrations of PAHs and PBDEs in human and sheep hair with concentrations measured in indoor and outdoor air, respectively. Evidence generated from this preliminary study suggests that hair might be used for the environmental monitoring of POPs in remote sites to provide a first-order estimate of ambient levels. Further studies are required to understand the uptake profiles and validate the use of hair as a sampling medium for POPs in ambient air.

Knowledge of Traction Alopecia and Hair Care Practices among Adolescents in Keffi, North-Central Nigeria

Background: Traction alopecia (TA) is the commonest cause of hair loss among women, with a prevalence of 46.2% in Nigeria. Adequate knowledge and good hair care practices can assist in its prevention. Objective: The aim of this study was to determine knowledge of both TA and hair care practices among adolescents in Keffi, Nigeria. Methods: This was a cross-sectional survey conducted among 333 female adolescents in 3 senior secondary schools between November 2019 and February 2020. The participants were randomly selected and interviewed using a questionnaire which sought information about the knowledge of TA and hair care practices. The data were analysed using SPSS 25 statistical software. Results: Overall, the knowledge score was poor in 61.4% of the adolescents. Hair plaiting 86.8% (289/333), use of chemical relaxers 68.8% (229/333), and use of hair covers 88.3% (294/333) were the predominant hair care practices. In total, 90.8% had concurrently relaxed and plaited their hair. Cornrows with own hair were the commonest hair grooming style. The use of hair attachments was believed to be the commonest cause of TA. The use of hijab was the commonest form of hair cover used. Conclusions: The knowledge of TA is poor among female adolescents. A large number engaged in risky hair care practices. Interventions to reduce the knowledge gap will reduce the prevalence of TA. Key Message: The knowledge of traction alopecia is poor among female adolescents in Keffi who engage in traumatic hair practices.

Detection of Methylphenidate in Equine Hair Using Liquid Chromatography-High-Resolution Mass Spectrometry.

Methylphenidate is a powerful central nervous system stimulant with a high potential for abuse in horse racing. The detection of methylphenidate use is of interest to horse racing authorities for both prior to and during competition. The use of hair as an alternative sampling matrix for equine anti-doping has increased as the number of detectable compounds has expanded. Our laboratory developed a liquid chromatography–high-resolution mass spectrometry method to detect the presence of methylphenidate in submitted samples. Briefly, hair was decontaminated, cut, and pulverized prior to liquid–liquid extraction in basic conditions before introduction to the LC-MS system. Instrumental analysis was conducted using a Thermo Q Exactive mass spectrometer using parallel reaction monitoring using a stepped collision energy to obtain sufficient product ions for qualitative identification. The method was validated and limits of quantitation, linearity, matrix effects, recovery, accuracy, and precision were determined. The method has been applied to confirm the presence of methylphenidate in official samples submitted by racing authorities.

Rodent hair is a Poor biomarker for internal manganese exposure

Hair is used as a biomarker of manganese (Mn) exposure, yet there is limited evidence to support its utility to quantify internal vs external Mn exposure. C57BL/6 J mice and Sprague-Dawley rats were exposed in two blocks of 3 subcutaneous injections every 3 days starting on day 0 or 20. The control group received two blocks of saline (vehicle); Treatment A received the first block as Mn (50 mg/kg MnCl2 tetrahydrate), with the second block as either methylmercury (MeHg at 2.6 or 1.3 mg/kg) for mice or vehicle for rats; and Treatment B received Mn for both blocks. Hair was collected on days 0 and 60 from all treatment groups and Mn quantified by inductively coupled plasma-mass spectrometry (ICP-MS) and total Hg by Direct Mercury Analyzer (DMA). No correlation between internal Mn dose and hair Mn was observed, whereas hair Hg was significantly elevated in MeHg exposed vs non-exposed mice. Whole body Mn content at day 60 was quantified postmortem by neutron activation analysis, which detected significantly elevated Mn for Treatment B in mice and rats. Overall, we find no evidence to support the use of hair as a valid biomarker for internal exposure to Mn at a neurotoxic level.