Serum mercury

Ahlqwist M, Bengtsson C, Lapidus L, et al A. Serum mercury concentration in relation to survival, symptoms, and diseases results from the prospective population study of women in Gothenburg, Sweden. Acta Odontol Scand 57 168-174, 1999... 

In the titrmetric procedure, the serum is diluted in 0.07 N nitric acid and titrated with a dilute mercuric nitrate solution in the presence of diphenylcarbazone (34). A purple color forms when excess mercury ions appear, over that needed to complex the chloride. Using an ultramicro buret this method has found wide use in the past. The microburets which are available such as the Rehburg buret are typified in Figure 22. 

El-Fawal HA, Gong Z, Little AR, Evans HL. 1996. Exposure to methyl mercury results in serum autoantibodies to neurotypic and ghotypic proteins. Neurotoxicology 17 267-276. 

Mercuric chloride, given for short time, has been reported to inhibit Na + /K + -ATPase in hog thyroid membranous preparation [149]. The blood T4 (thyroxine) levels were reduced and iodotyrosine deiodinase was inhibited, and it was suggested that mercurials might cause a coupling defect in the synthesis of iodothyronines. In mouse thyroid serum T4 level was affected by mercuric chloride, while serum T3 was not [ 150 ]. It was suggested that thyroidal secretion of T4 was inhibited by mercuric chloride, but the peripheral conversion of T4 to T3 might not be affected in the maintenance of an active hormone level. 

New York Developing capacity to monitor for polyaromatic hydrocarbons (PAHs) in urine, polybrominated diphenyl ethers (PBDEs) in serum, organochlorine pesticides in serum, volatile organic compounds (VOCs) in blood, cotinine in saliva, trace elements in blood and urine, inorganic mercury in blood and to generate data on exposure to persistent organic pollutants (CDC 2005). 

Reference ranges have been established for arsenic, lead, cadmium, mercury, platinum, nickel in blood and urine pentachlorophenol and metabolites of organophosphorus in serum and urine PCBs, fi-HCH, HCB, DDE in blood organochlorine pesticides (fi-HCH, HCB, total DDT) in human milk... 

The New Hampshire Department of Health and Human Services is determining blood mercury concentrations and related freshwater fish consumption, studying speciated arsenic in urine, and analyzing phthalates in urine and PBDEs in serum and breast milk (APHL 2004, 2006). In 2004, New Hampshire received about 300,000 to support its biomonitoring program (APHL 2004). 

Like cadmium, mercury(II) has a strong affinity for sulfhydryl groups in proteins, enzymes, hemoglobin, and serum albumin. Because of the abundance of sulfhydryl groups in active sites of many enzymes, it is difficult to establish exactly which enzymes are affected by mercury in biological systems. 

Another major exposure route for humans is via contaminated food. For example, North America s Great Lakes, which are the largest body of freshwater in the world, are polluted with about 362 contaminants that were found in quantifiable amounts in the water, sediment, and biota (IJC 1983 USEPA 1994). The critical pollutants were identified as PCBs, DDT, dieldrin, toxaphene, mirex, methyl mercury, benzofa) pyrene, hexachlorobenzene, polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and alkylated lead. Some of these pollutants biomagnify in the aquatic food chain and can be detected in increased levels in cooked Great Lakes fish. Consequently, the blood serum levels of these chemicals are significantly increased in consumers of contaminated Great Lakes sport fish compared to people who do not eat such fish (Flumphrey 1983 Fiore et al. 1989 Sonzogni et al. 1991). 

The principle of the isotope dilution analysis (IDA) is described in Section 6.4. Due to its advantages as a definitive and accurate analytical method for the determination of element concentration via isotope ratio measurements, IDA is being increasingly applied in mass spectrometry, especially in ICP-MS and LA-ICP-MS as one of the most frequently used techniques. For example, the isotope dilution technique is employed in species analysis in biological systems, " e.g., for the determination of mercury species in tuna material,or in aquatic systems. Further applications of the isotope dilution technique are the determination of selenomethionine in human blood serum by capillary HPLC-ICP (ORC) MS ° or sulfur speciation in gas oil, diesel or heating fuel by LA-ICP-MS. Evans and co-workers have reported on the high accuracy analysis of sulfur in diesel fuel by IDA. ICP-SFMS has been employed for Si species analysis in biological or clinical samples and... 

Systemic evaluation of the patient includes a complete blood count, blood chemistry, thiamine level, urinalysis, serum vitamin B12 and folate levels, heavy metal screening (lead, mercury, arsenic), and tests for megaloblastic anemia. The hair may also be tested for indications of toxicity. 

Finally, the nephrotoxicity of inorganic mercury (i.e. mercuric chloride) has been shown to be the result of a GSH or cysteine conjugate. In a series of experiments, Zalups has shown that mercuric chloride in the blood is conjugated to cysteine and GSH as mono- or di-substituted conjugates and to serum proteins [38]. 

Tamir M, Boustein B, Behar M, Chwat M. Mercury poisoning from an unsuspected source. Br J Ind Med 1968 21 299-303. Deutsch MF, Morton Jl. Dissociation of human serum macroglobulins. Science 1957 125 600-601. 

Bernard AM, Roels HA, Foldart JM, Lauwerys RR. Search for antl-lamlnin antibodies In the serum of workers exposed to cadmium, mercury vapour or lead. Int Arch Occup Environ Health 1987 59 303-309. 

However, most studies on humans occupationally exposed to mercury identify no effects on immunological markers such as serum immunoglobulins and autoantibodies [73,74], albeit Ellingsen et al. [75] noted subtle elevations in plasma antibodies against myeloid peroxidase (anti-MPO) and proteinase 3 (anti-PR3). 

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