Nails analysis

Nail analysis has not been widely utilized in forensic toxicology, but some methods have been reported using GC (124). Nail samples receive similar treatment to hair samples for extraction of the drug. 

Needless to say, an analysis which will finally allow one to nail down all rates, activation parameters, and equilibrium constants requires a large amount of precise and reliable kinetic data from appropriate experiments, including the determination of isotope effects and the like, as well as a rather sophisticated treatment and solution of the complete kinetic scheme. Then a comparison is necessary between various organosilanes with different types of C-H and C-Si bonds as well as the comparison between the dtbpm and the dcpm ligand systems, not to speak of model calculations in order to understand the molecular origin of the kinetic and thermodynamic numbers. We are presently in the process of solving these problems. 

Radioactivation analysis is used for the analysis of trace amounts of suitable elements. It is a technique that is not generally applicable to biological material although it has been used for the measurement of lead in hair and nails. 

But if 1 wanted to help this person stop smoking or overcome depression, 1 probably wouldn t use just the tool of handwriting analysis. That would be like using a screwdriver to hammer in a ten-inch nail. There are better tools for that job. 

Analysis of tissues such as nails, hair, and bone, where chemicals are deposited but not readily released (Figure 3.1), is useful to determine whether an individual had ever been exposed to a particular chemical, but is of less value in determining recent exposure and causation. 

Ingested arsenic is known to be not only excreted by urine, but also to be stored in sulfydryl rich tissue like hair, nails or skin. A method of extracting arsenic species from hair and nail samples has been developed for the analysis of the total arsenic concentration, inorganic As ( ) and As... 

One of the most famous applications in forensic science is the analysis of Napoleon s hair by ICP-MS after mineralization in concentrated nitric acid whereby an arsenic concentration about 40 times higher than normal (about 40p,gg 1) was measured (see Section 9.5). Ingested arsenic is known to be stored in sulfydryl rich tissue, like hair, nails or skin. ETV-ICP-MS combined with isotope dilution has been employed to measure thallium in human scalp hair from a person poisoned by thallium compared to control subjects, whereby several longitudinal concentration gradients for the analyzed segments (length 10 mm) were obtained.28... 

Sheldon L, Umana M, Bursey J, et al. 1986. Biological monitoring techniques for human exposure to industrial chemicals Analysis of human fat, skin, nails, hair, blood, urine, and breath. Park Ridge, NJ Noyes Publications, 86-122. 

Analysis of hair, fingernails, and toenails can serve as evidence of arsenic ingestion. Such analyses are complicated by the possible presence of arsenic contamination, particularly in a work environment in which the air and surroundings may be contaminated with arsenic. Levels of arsenic may be correlated with the growth of nails and hair so that careful analysis of segments of these materials can indicate time frames of exposure. 

Crystal-Field Analysis of Ho3+-LaF3 and Er3+-LaF3 in C2V-Site Symmetry, W.T. Car-nail, G.L. Goodman, R.S. Rana, R Vandevelde, L. Fluyt, and C. Gorller-Walrand, J. Less-Common Met. 116, 17-29 (1986). 

Hair, Nail, Skin. Differences can be seen by thermal analysis between grossly different samples (e. g.,bleached, unbleached hair (18) ), but this does not appear at present to be a promising area for thermal analysis. 

Keratin is a natural single-strand polymer consisting of chains of amino acids, with a high proportion of the two sulfur-containing amino acids cysteine and methionine. Keratin is the polymer of hair and nails. The sulfur atoms account for keratin s ability to bond to arsenic, mercury, and lead. Hair analysis has played an important role in forensic evidence in cases of poisoning, and it has been possible to diagnose the extent to which famous people in history were affected by these toxic elements provided a sample of their hair has been preserved. 

If it is considered that the deceased had been poisoned over an extended period prior to death, it is important to collect hair (plucked from the roots with the ends tied with thread at the scalp end) and nail specimens. The growing hair and nail can absorb many trace elements from the blood stream and these elements are permanently bound to the keratin. Knowing that the average rate of growth of human hair is approximately 1cm per month, sectional analysis of the hair from the root to the tip will produce a calendar of exposure to the element. 

Arsenic is concentrated in the liver, spleen and kidney and is bound preferentially to sulphydryl groups in skin, hair and nails. Urine and gastric contents should also be obtained. The sequential analysis of hair sections has been shown to be of value in the examination of prolonged exposure to arsenic [8]. 

Valkovic, V, Human Hair Trace Element Levels, Volume 11, CRC Press, Boca Raton, FL, 1988. Hopps, H. C., The biologic basis for using hair and nail for analysis of trace elements, Sci. Total Environ., 7, 71, 1977. 

Suzuki, S., Inoue, T., Yasuda, T., Analysis of Methamphetamine in Hair, Nail, Saliva and Sweat by Mass Fragmentography, in TIAFT Proceedings of the 21 International Meeting, Brighton (1984), Dun-nett, N., Kimber, K. J., Eds., McMillan, New York, 1984, 95. 

Suzuki, S., Inoue, T., Hori, H., Inayama, S., Analysis of methamphetamine in hair, nail, sweat and saliva by mass fragmentography, J. Anal Toxicol, 13,176-178,1989. 

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