The Person Beneath the Hair: Hair Discrimination, Health, and Well-Being

Discrimination toward black hair is pervasive in today's society. Hair discrimination is negative bias manifested toward black natural or textured hair styles typically worn by persons of African descent. This commentary discusses the potential effects of hair discrimination on the health and well-being of persons of African descent. Specifically, it explores the mental and physical health implications of hair discrimination and situates it within the broader context of social determinants of health. The Creating a Respectful and Open World for Natural Hair Act has been recently passed in the United States House of Representatives, but more work is needed to eliminate hair discrimination and its negative effects.

Current status of hair analysis in forensic toxicology in China

Hair analysis has been mainly used to document drug use history in abusers, drug-facilitated crime cases, doping control analysis and postmortem toxicology in the fields of forensic toxicology, clinical toxicology, and doping control. Hair analysis has also gained more attention in the last 30 years in China. Relevant technology has been promoted as more research has appeared concerning hair analysis, and consensus has been sought among forensic toxicologists regarding aspects such as hair decontamination treatment, detection of abused substances in hair, segmental hair analysis and interpretation of analytical results. However, there are still some limitations in the estimation of drug intake time and frequency by segmental hair analysis due to the different growth cycles evident within a bundle of hairs, the drug incorporation mechanism and sampling errors. Microsampling and imaging mass spectrometry (IMS) technology based on a single hair may be a good choice to estimate drug intake time more accurately. Analysis of hair root samples may also be used to document acute poisoning in postmortem toxicology, and the analysis of the hair shaft can document long-term use of drugs depending on the length of the hair being evaluated.

Nonpigmented hair removal using photodynamic therapy in animal model

BACKGROUND AND OBJECTIVE

Lasers have been successfully used for decades to remove dark hair. However, laser removal of nonpigmented hair is challenging due to the lack of chromophores. The aim of this study was to use photodynamic therapy (PDT) to remove nonpigmented hair.

STUDY DESIGN/MATERIAL AND METHODS

We compared the efficacy of permanent hair reduction in white BALB/c and black C57BL/6 mice treated with PDT or an 800-nm diode laser. We collected skin biopsy specimens and investigated post-PDT histologic changes and molecular changes.

RESULTS

We observed keratin 15 staining in the bulge area and alkaline phosphatase staining in the dermal papilla following PDT. We observed a temporary, catagen-like transformation in nonpigmented hair follicles after PDT. We observed apoptotic cells in the hair matrix after PDT. Irradiation with an 800-nm diode laser did not achieve nonpigmented hair removal. Multiple PDT sessions achieved permanent reduction of nonpigmented hair. Interestingly, removal of black hair using PDT was less efficient.

CONCLUSION

Our results suggest that PDT can damage the nonpigmented hair matrix, but not stem cells or dermal papillae. Repeated PDT may impair the hair-regeneration capacity via a bystander effect on bulge stem cells or dermal papillae. In this study, we found it was possible to remove nonpigmented hair using PDT. Lasers Surg. Med. 48:748-762, 2016. © 2016 Wiley Periodicals, Inc.