Hair manganese

Two studies in school children (He et al. 1994 Zhang et al. 1995) showed that over-exposure to manganese in drinking water and food was associated with poorer performance in school and on neurobehavioral tests as compared to non-exposed children. The exposed and control children in these studies were reportedly well-matched and the reports indicated that hair manganese was inversely related to performance on neurobehavioral exams and in school. However, there were several limitations in the reporting of the study, including the lack of analysis for lead or mercury, which are neurotoxins, and the lack of definitive exposure characterization. 

Methods were used to determine levels of chromium, lead, and cadmium in hair. Manganese concentrations in hair were evaluated for some, but not all, of the samples and tested one, but not both, new methods. However, it is assumed that both techniques will work for the trace element manganese. 

Similar results have emerged from a study of 83 children aged 6-12 years and their mothers, in whom blood and hair manganese concentrations were measured [76 ]. Maternal and children s hair concentrations correlated and the children s hair concentrations were negatively related to total and verbal IQ. 

Nervous System Arsenic and manganese exposure is associated with neurodevelopment problems in children. Study reveals that a 50% increase of urine arsenic concentration and hair manganese levels may decrease the intelligence quotient (IQ) by 0.4 in children aged 5-15 years and by 0.7 in children aged 6-13years, respectively [48 ]. 

Manganese deficiency has been reported only in association with chemically defined manganese-deficient oral diets. The symptoms include nausea, vomiting, dermatitis, color changes in hair, hypocholesterolemia, and growth retardation. 

In the second method, a metal salt solution (silver, lead, or bismuth less often nickel, cobalt, or manganese) is applied colloidal sulfur may also be added. Dyeing is based on (1) The reaction of the metal salts with the added sulfur and the sulfur in the hair keratin, which yields metal sulfides, and (2) The deposition of finely divided metals or metal oxides. With these products progressive coloration also is obtained. 

Melanin granules are secreted by melanocytes in the hair papilla and distributed to keratin in the hair cortex and inner layers of the hair sheath during normal development. Melanogenesis is subject to hormonal control and has been the focus of intensive genetic studies. Two main forms of melanin exist in human skin—eumelanin and phaeomelanin, both of which are derived from tyrosine through the action of tyrosinase (a cupro-enzyme) and possibly other key enzymes (with nickel, chromium, iron, and manganese as cofactors). Tyrosine is converted to dihydroxyphenylalanine and, via a series of intermediate steps, to indole-5,6-quinone, which polymerizes to eumelanin. Phaeomelanins are produced by a similar mechanism but with the incorporation of sulfur (as cysteine) by a nonenzymatic step in the oxidation process. 

Wright RO, Amarasiriwardena C, Woolf JR, Bellinger DC (2006) Neuropsychological correlates of hair arsenic, manganese, and cadmium levels in school-age children residing near a hazardous waste site. Neurotoxicology, 27(2) 210-216. 

Mehra R, Bhalla S. 1998. Determination of chromium, manganese, iron and nickel content of hair for evaluating exposure to metals in occupational environment. Oriental Journal of Chemistry 14(1) 117-120. 

Stupar J, Dolinsek F. 1996. Determination of chromium, manganese, lead and cadmium in biological samples including hair using direct electrothermal atomic absorption spectrometry. Spectrochim Acta Part B 51 665-683. 

The first report of an experimentally-induced deficiency was by Doisy (1) who fed two subjects a formula diet that was deficient in vitamin K. One of the subjects developed a slight reddening of the hair, a scaly, transient dermatitis, depressed vitamin K-dependent clotting factors, and hypocholesterolemia. The symptoms were unresponsive to vitamin K but disappeared when a normal diet was resumed. When Doisey recalculated his purified diet, he realized that he had inadvertently omitted the manganese. The diet had contained a manganese level of only 0.34 mg/day and apparently had produced a manganese deficiency. 

Different metals and metal compounds have been in use since the beginning of human civilization. Metals include aluminum, antimony, cobalt, copper, chromium, iron, nickel, manganese, molybdenum, selenium, tin, vanadium, and zinc. The list of toxic metals includes but is not limited to arsenic, beryllium, cadmium, hexavalent chromium, lead, and mercury. Contamination of food, water, and the air by metals, particularly lead and cadmium, has caused global concern. Several studies have shown elevated levels of lead, nickel, chromium, and manganese in children s hair. 

Manganese Nausea, vomiting, dermatitis, hair color changes, hypocholesterolemia, growth retardation, defective carbohydrate and protein metabolism Parkinsonian-like symptoms, hyper irritability, hallucinations, libido disturbances, ataxia Increased decreased biliary excretion high iron or vitamin C intake... 

Interestingly, the average manganese content in scalp hair among male and female Aborigine residents was... 

Manganese has been found to have an affinity for melanin (it was found to bind to beef eye, human hair, and synthetic dopamine melanin) although functional damage has not been reported (Lyd6n et al. 

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