Contamination from sweat

The high sensitivity of modem instrumental techniques such as ICP-MS (Chapter 9) means that in many cases only small samples (typically, a hundred milligrams or less) need be taken for destructive analysis. However, this also means that the amounts of some individual elements may be very low, and problems of contamination can be significant. Common external contaminants include A1 from deodorants, Pb from paint or car exhausts, Zn from skin particles (and therefore from dust), and Na from sweat. The levels of contamination for each batch of samples will be revealed by the sample... 

Potentials problems with the use of hair include a strong influence of hair pigmentation on nicotine and cotinine binding and uptake (Dehn et al. 2001). Nicotine and cotinine are bound to melanin. As a result, dark hair binds much more nicotine than does blond or white hair. This makes comparison across individuals difficult. Also, hair is exposed to nicotine and cotinine from sweat and from sebaceous gland secretions, and to nicotine from environmental tobacco smoke exposure. Washing the hair before analysis may reduce this problem of environmental contamination, but it is not likely to remove all environmental nicotine and cotiiune. 

However, in the light of multiple experimental findings based upon more accurate and precise techniques, this model seems to be oversimplified since it does not take into account the potential transfer of drugs from sweat, sebaceous and apocrine gland secretions, nor the external contamination even via deep compartments located in the skin surrounding the hair follicle. 

Direct determination of trace elements is made in many types of specimens including whole blood, blood plasma or serum, leukocytes, urine, saliva, cerebrospinal fluid (CSF), breast milk, and sweat. Tissue samples may be obtained by needle biopsy (liver, bone,) or following an autopsy. Hair and nail samples offer a noninvasive means of sampling tissue and are used to assess toxic metal exposure. Measurements of hair and nails for essential elements may be of value on a group basis during studies of severely depleted populations but are of Umited value in the investigation of individual hospital patients. Problems of external contamination from environmental pollution, cosmetics, shampoos, and other sources are difficult to control. ... 

The mechanisms by which drugs are deposited in hair are not well understood but may include transfer from blood to the growing hair shaft, transfer from sweat and sebum (some sweat glands empty into hair follicles), and environmental contamination. Factors that may affect the deposition of drugs in hair also are not well established but may include the rate of hair growth, anatomical location of hair, type of hair, hair color (melanin content), effects of various hair treatments, and environmental contamination, especially for drugs that are smoked (marijuana, cocaine, heroin, and PCP). 

Radioactive iodine is excreted primarily in the urine and in smaller amounts in saliva, sweat and feces. The contamination in sweat is small. According to the findings of Lassman et al. (1998) and Schomaecker et al. (2000), less than 0.1% is exhaled. Jacobson et al. (1978) have shown that internal doses resulting from contamination and intake of are likely to be much smaller (a factor of over 100) than external exposure to radiation from patients. Next to urine, the highest iodine excretion is in saliva. The activity in the salivary glands has been found to be proportional to the administered activity. In a study by O Doherty et al. (1993), it was shown that the maximal salivary activity occurs approximately 24 h post-administration. 

Other soils that shampoos must remove are proteinaceous matter arising from the stratum corneum, sweat, and other environmental sources. We have already described metallic ion contamination from the water supply, from swimming pools, and from sweat. In addition, particulate soils from the environment include hydrocarbons, soot, and metal oxide particles, which should also be removed by shampoos [13]. 

Nickel sulfate is present on the surface of used coins, and nickel ions are rinsed off by contact for only 1 min with artificial sweat. Copper/nickel coins stored in artificial sweat for 7 days give high release of nickel ions (up to 45 pg/cm per week) (Consumer Safety Group 1997). Hands become contaminated by nickel when handling coins and can also become contaminated from handling contaminated non-nickel coins and bank notes (Bang Pedersen et al. 1974). 

All metal surfaces such as mild steel should be grit blasted, normally to SA 2-5 as defined in Swedish Standard SIS 055900. If the surfaces are contaminated with oil, grease or a chemical from previously used items, the contamination is usually removed by sweating in steam prior to grit blasting. Concrete surfaces must be clean and dry and any laitence must be removed as it will affect the bond of the lining. Preferably the surface should be grit blasted. 

Sweat from the fingers and palms of the hands is rich in trace metals (25) and is a common source of contamination in... 

HEALTH HAZARD DATA Same as GD except for skin contact. For skin contact, don respiratory protective mask and remove contaminated clothing. Immediately scrape the TGD from the skin surface, then wash the contaminated surface with acetone. Administer Nerve Agent Antidote Kit, MARK I, only if local sweating and muscular twitching symptoms are observed. Seek medical attention IMMEDIATELY. 

Little information is available on drug secretion into sweat it is used very little because of the difficulty of excluding topical contamination. It is collected almost exclusively from the horse, the most convenient technique being to use a scraper and absorbent gauze. 

Contamination. Fats and oils with appreciable amounts of phosphatides and other easily hydratable materials, such as those from soybean, cottonseed, corn, rapeseed, etc., can be contaminated with moisture. Conditions of high humidity, warm oil, and cool temperatures can produce sweating within crude oil storage... 

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