As unhas das mãos e dos pés são feitas de uma proteína resistente chamada creatina. Juntamente com o cabelo e os dentes são um apêndice da pele. Estes tecidos acumulam metais que circulam na corrente sanguínea, de acordo com os crescimentos normais do cabelo e das unhas, refletem a exposição passada ou crônica.
O crescimento médio da unha tem sido anotado por diferentes autores entre 2-3mm por mês, e é considerado aproximadamente 1/3 da taxa de crescimento do cabelo. A substituição da unha completa pode demorar entre 3 a 6 meses, e unha do pé demora de 12 a 18 meses. A taxa de crescimento real está dependente da idade, sexo, estação, nível de exercício, dieta e fatores hereditários. A gravidez provoca uma alteração no crescimento das unhas, como faz no crescimento do cabelo.
Fingernails and toenails are made of a tough protein called keratin. Along with hair and teeth they are an appendage of the skin. These tissues accumulate
metals that circulate in the blood stream, due to the growth pattern both hair and nail reflect past or chronic exposure.
The average nail growth has been noted by different authors between 2-3mm per months, and is considered about 1/3 the growth rate of hair. A complete nail replacement may take between 3 to 6 months, and toenails require 12 to 18 months. The actual growth rate is dependent upon age, gender, season, exercise level, diet, and hereditary factors. Pregnancy causes a change in nail growth as it does in hair growth.
Arsenic and other elements in hair, nails, and skin-scales of arsenic victims in West Bengal, India.
Samanta G., Sharma R., Roychowdhury T., Chakraborti D. Department of Civil and Environmental Engineering, University of Houston, N 107 Engineering Bldg 1, Houston, TX 77204-4003, USA. gsamanta@mail.uh.edu. Sci Total Environ. 2004 Jun 29;326(1-3):33-47.
For the first time, biological tissues (hair, nails, and skin-scales) of arsenic victims from an arsenic affected area of West Bengal (WB), India were analyzed for trace elements. Analysis was carried out by inductively coupled plasma-mass spectrometry (ICP-MS) for 10 elements (As, Se, Hg, Zn, Pb, Ni, Cd, Mn, Cu, and Fe). A microwave digester was used for digestion of the tissue samples. This study reveals the higher levels of toxic elements As, Mn, Pb, and Ni in the tissue samples compared with available values in the literature. The elevated levels of these toxic metals in the tissues may be due to exposure of these elements through drinking water and food. This study reveals that in the arsenic-affected areas of WB, the concentrations of other toxic elements in drinking water and foodstuff should be monitored to evaluate the arsenic poisoning.
HAIR and NAILS are similar body tissues. They do have a different growth rate and thus reflect a different period of metal storage in tissue. For this reason, we recommend that you send either hair or nails, not both.
The sample can be placed in a plain envelope for shipping. Download and fill out the submission sheet (see submission forms) and send both to our laboratory.
Reports are released within one week (per post or e-mail) after sample and submission sheet have arrived at our laboratory.
Fisiologicamente, a unha pode detetar o histórico de desequilíbrios recentes. Como a Academia Americana de Dermatologia ('American Academy of Dermatology'), declarou em seu site, a unha tem sido usada como uma ferramenta de diagnóstico desde a antiguidade. Deficiências nutricionais, reação a drogas ou envenenamento podem ser localizados através da análise das unhas. Análise mineral da unha reflete a exposição a substâncias tóxicas que aconteceram durante o período de crescimento.
Micro Trace Minerals estabeleceu valores de referência para as unhas na década de 80.