Mangan i jego związki nieorganiczne – w przeliczeniu na Mn

• Autorzy: Starek A.
• Języki publikacji: PL

Abstrakty

PL

Mangan (Mn) jest metalem przejściowym, który występuje na: 0, II, III, IV, VI i VII stopniu utlenienia. Metal ten jest stosowany do produkcji stopów metali żelaznych i nieżelaznych, a jego związki mają wszechstronne zastosowanie. Narażenie zawodowe na mangan występuje: w górnictwie rud manganu, przy jego produkcji i jego stopów, podczas prac spawalniczych oraz podczas otrzymywania i stosowania jego związków. Wielkość narażania zawodowego na mangan na ogół nie przekracza 1 mg/m3 (frakcja wdychana pył całkowity) oraz 0,1 mg/m3 (frakcja respirabilna). Według danych Instytutu Medycyny Pracy w Łodzi z 1994 r. w Polsce było 3505 osób narażonych zawodowo na mangan o stężeniach przekraczających wartość najwyższego dopuszczalnego stężenia (NDS) wynoszącą 0,3 mg/m3, natomiast wg danych Głównej Inspekcji Sanitarnej z 2007 r. na mangan i jego związki nieorganiczne (w przeliczeniu na Mn) było narażonych 1011 pracowników. W przewlekłym zatruciu manganem u ludzi przeważają zaburzenia ze strony układu nerwowego i oddechowego. Po stosunkowo małych wielkościach narażenia zawodowego u pracowników obserwowano subkliniczne zmiany neurobehawioralne. U zwierząt laboratoryjnych w warunkach narażenia powtarzanego na mangan obserwowano zmiany w metabolizmie neuroprzekaźników oraz zaburzenia neuroczynnościowe. Mutagenne działanie manganu było słabo zaznaczone. Mangan nnie jest klasyfikowany jako czynnik rakotwórczy. Brak jest również jednoznacznych dowodów na jego wpływ na rozrodczość. Wydaje się, że ze względu na możliwą kumulację skutków działania manganu na ośrodkowy układ nerwowy (OUN) bardziej wartościowe do ustalenia wartości NDS są wyniki badań dotyczące narażenia skumulowanego. Na podstawie wyników pracy Roelsa i in. wykazano, że skumulowane narażenie na mangan o stężeniu 3575 mg/m3 razy lata pracy w narażeniu (frakcja wdychalna) i stężenie 0,73 mg/m3 razy lata pracy w narażeniu (frakcja respirabilna) powodowało występowanie wczesnych objawów działania na OUN u 5% populacji. Jeśli przyjmiemy 20 lat pracy w narażeniu na mangan, to stężenia manganu w powietrzu środowiska pracy wyniosą odpowiednio 0,178 (frakcja wdychalna) oraz 0,036 mg/m3 (frakcja respirabilna). W badaniu Myersa i in. w grupie 489 górników narażonych na mangan w postaci pyłu całkowitego o stężeniu 0,21 mg/m3 (średnia arytmetyczna) przez średni okres 10,8 lat pracy nie obserwowano subklinicznych zaburzeń neurobehawioralnych związanych z narażeniem. Na podstawie wyników wymienionych prac wykazano, że można zaproponować przyjęcie stężenia 0,2 mg/m3 za dopuszczalną wartość stężenie manganu zawartego we wdychalnej frakcji pyłu. Ponieważ mangan we frakcji respirabilnej stanowi około 25% manganu obecnego w pyle całkowitym, dlatego proponuje się ustalenie wartości NDS dla tej frakcji jako ¼ obliczonej wcześniej wartości NDS, tj. 0,05 mg/m3. Proponuje się przyjęcie wartości NDS dla manganu na poziomach 0,2 mg/m3 i 0,05 mg/m3 odpowiednio dla frakcji wdychalnej i frakcji respirabilnej. Proponowane wartości powinny chronić pracowników przed subklinicznymi zaburzeniami neurobehawioralnymi wywołanymi narażeniem na mangan. Nie znaleziono merytorycznych podstaw do ustalenia wartości najwyższego dopuszczalnego stężenia chwilowego (NDSCh) manganu oraz jego dopuszczalnego stężenia w materiale biologicznym (DSB).

EN

Manganese (Mn) is a transition metal, which occurs in several oxidation states (0, II, III, IV, VI and VII) and forms a range of inorganic compounds. Manganese is a very hard, brittle metal, which is used in the production of ferrous and non-ferrous metal alloys, including those essential to steel making. This metal increases the strength of steel alloys. Iron and steel production accounts for 85 ÷ 95% of the manganese market. Its compounds have comprehensive applications. In industrial conditions, there is occupational exposure especially in mining, metal smelting, steel production, battery manufacture, welding, agricultural production and use, and in pigment, paint and glass making. Workers can be exposed to dust and fumes of manganese-containing compounds in a range of particle sizes where the ratio of inhalable to respirable fractions varies within and between industries. Manganese is an essential element; it is involved in bone formation and amino acid, carbohydrate and cholesterol metabolism. It is a component of several enzymes and it activates others. It is estimated that in Poland in 1994 about 3500 workers were exposed to manganese at levels above the maximum admissible concentration (MAC) of 0.3 mg/m3. However, according to data provided by the Chief Sanitary Inspectorate, about 1000 persons were exposed to manganese and its inorganic compounds in 2007. In persons chronically exposed to manganese and its compounds via inhalation disorders of both the central nervous and the respiratory system predominate. Subclinical neurobehavioral changes have been observed in workers occupationally exposed to relatively low levels of this metal. There have been changes in neurotransmitters metabolism and neurofunctional disorders in laboratory animals repeatedly exposed to manganese. The mutagenicity of this metal was weakly marked. Manganese is not classified as a chemical carcinogen. On the basis of the results of epidemiological examinations the MAC values for manganese and its inorganic compounds were established at 0.2 mg/m3 and 0.05 mg/m3 for inhalable and respirable fractions, respectively. No STEL (15 mins) and BEI values have been proposed.

Słowa kluczowe

PL

mangan; narażenie zawodowe; toksyczność; NDS

EN

manganese; occupational exposure; toxicity; MAC

• Wydawca: Centralny Instytut Ochrony Pracy - Państwowy Instytut Badawczy
• Czasopismo: Podstawy i Metody Oceny Środowiska Pracy
• Rocznik: 2012
• Tom: Nr 1 (71)
• Strony: 27--58
• Opis fizyczny: Bibliogr. 81 poz., rys., tab.

Twórcy

autor

Starek A.

• Collegium Medicum Uniwersytetu Jagiellońskiego 30-688 Kraków ul. Medyczna 9

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