Fumes manganese

Exposure to manganese dusts, fume, and compounds should not exceed the ceiling value of 5 mg/ms for even short periods because of the element s toxicity level. 

Health and Environment. Manganese in trace amounts is an essential element for both plants and animals and is among the trace elements least toxic to mammals including humans. Exposure to abnormally high concentrations of manganese, particulady in the form of dust and fumes, is, however, known to have resulted in adverse effects to humans (36,37) (see Mineral nutrients). 

Impurities in mineral fillers can have serious effects. Coarse particles (grit) will lead to points of weakness in soft polymers which will therefore fail under stresses below that which might be expected. Traces of copper, manganese and iron can affect the oxidative stability whilst lead may react with sulphur-containing additives or sulphurous fumes in the atmosphere to give a discoloured product. 

Magnesium oxide fume Malathion Maleic anhydride Manganese Manganese fume MBK (2-hexanone)... 

Investigation showed that commercial titanium alloys in contact with acid containing less than 1.34% water and more than 6% of dinitrogen tetraoxide may become sensitive to impact, and react explosively with the acid. Possible causes are discussed [1]. The spongy residue formed by prolonged corrosion of titanium-manganese alloys by red fuming nitric acid will explode on exposure to friction or heat [2],... 

Welding Fumes, gases oxides of cadmium, chromium, fluorides, iron, manganese, nickel, nitrogen, vanadium, by-products from fluxes, coatings, electrodes... 

The dust and fumes from the powder form of most manganese compounds, especially the oxides, are very toxic to plants, animals, and humans. Even inhaling small amounts is toxic. The powder form of manganese metal is flammable, and manganese fires cannot be extinguished with water. They must be smothered by sand or dry chemicals. 

In a report of five cases of manganism in a steel plant, three resulted from exposure to ferromanganese fume and two from exposure to ferromanganese dust. As indicated above, ferromanganese fume is primarily manganese tetroxide. Two of the workers exposed to the fume worked in a pig casting operation where the exposure was estimated to have been 13.3 mg/m for 5 years. 

It is generally held that manganese fume is more hazardous than equivalent concentrations of manganese-containing dust. 

The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) for manganese fume is Img/m with a short-term excursion limit (STEL)/ceiling of 3 mg/mk... 

Although trace amounts of manganese are essential for animals, in large quantities the metal can cause acute and chronic poisoning. Chronic inhalation of metal dust or fumes can cause manganism, a nonfatal disease affecting the central nervous system. The symptoms are mental disorder and disturbance in speech. 

Manganese Nitrohydrazinate. Mn(N03)2 -2N2H4. Calcd Mn 22.8% and N2H4 33.6% found Mn 23.6% and N2H 33.5%. Reddish (ochre) colored hexagonal crystals ignites easily ca 150°, produces copious fumes of Mn oxide is insensitive to shock (Ref 3)... 

Bromine.—Of the three halogens, chlorine, bromine, and iodine, bromine has the least eventful history. Its elemental nature and its relation to chlorine and iodine were recognized from the very first. While studying the mother-liquid which remains after the crystallization of salt from the water of the salt-marshes of Montpellier, A. J. Balard was attracted by the intense yellow coloration developed when chlorine water is added to the liquid. A. J. Balard digested the yellow liquid with ether decanted off the supernatant ethereal soln. and treated this with potassium hydroxide. The colour was destroyed. The residue resembled potassium chloride but unlike the chloride, when heated with manganese dioxide and sulphuric acid it furnished red fumes which condensed to a dark brown liquid with an unpleasant smell. 

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