Health Canada
Symbol of the Government of Canada

Common menu bar links

Environmental and Workplace Health

Manganese

May 1979
(Updated November 1987)

Help on accessing alternative formats, such as Portable Document Format (PDF), Microsoft Word and PowerPoint (PPT) files, can be obtained in the alternate format help section.

Table of Contents

Manganese

The aesthetic objective for manganese in drinking water is =0.05 mg/L (=50 g/L). The presence of manganese in drinking water supplies may be objectionable for a number of reasons. At concentrations above 0.15 mg/L, manganese stains plumbing fixtures and laundry and produces undesirable tastes in beverages. As with iron, the presence of manganese in water may lead to the accumulation of microbial growths in the distribution system. Even at concentrations below 0.05 mg/L, manganese may form coatings on water distribution pipes that may slough off as black precipitates.

General

The element manganese is present in over 100 common salts and mineral complexes that are widely distributed in rocks, in soils and on the floors of lakes and oceans. Manganese is most often present as the dioxide, carbonate or silicate. It may exist in oxidation states ranging from -3 to +7; the manganous (Mn2+) and manganic (Mn4+) oxidation states are the most important for aquatic systems.Footnote 1

In Canada, manganese is primarily employed in the steel industry, where it is used to counteract the effects of sulphur, as a deoxidizing agent and as an ingredient in special alloys. Manganese is also used in the manufacture of dry cell batteries and as an oxidizing agent in the chemical industry. In 1985, about 25 398 t of ferromanganese, 6979 t of silicomanganese, 102 048 t of manganese ore and 3240 t of manganese metal were imported into Canada; 22 408 t of ferromanganese were exported.Footnote 2

Occurrence

Manganese is the principal constituent of manganese nodules and ferromanganese oxide concretions found in the Great Lakes and in several lakes in eastern Ontario.Footnote 3,Footnote 4,Footnote 5 The weathering products of surficial manganese deposits contribute only slightly to the manganese content of river and sea water.

Manganese is generally present in natural surface waters as dissolved or suspended matter at concentrations below 0.05 mg/L. A survey of Canadian surface waters undertaken in 1980-1981 showed that the usual range of manganese in freely flowing river water was 0.01-0.40 mg/L. The highest concentrations recorded were in the Carrot River in Saskatchewan; dissolved manganese reached 1.7 mg/L, whereas extractable manganese peaked at 4.0 mg/L.Footnote 6 Manganese is more prevalent in groundwater supplies than in surface water supplies owing to the reducing conditions that exist underground. High concentrations of manganese are also found in some lakes and reservoirs as a result of acidic pollution; in 1972-1973, a mean manganese concentration of 0.26 mg/L was recorded in a small acidic lake near Sudbury, Ontario.Footnote 7

During 1974-1976, 67% of 84 national sampling sites for drinking water had manganese concentrations below 0.02 mg/L; concentrations above 0.05 mg/L were recorded at 25% of the stations.Footnote 8 A survey of 20 drinking water treatment plants in Ontario during 1985-1986 showed mean manganese concentrations of 0.014 mg/L and 0.008 mg/L in the raw and treated water, respectively. Concentrations of manganese were consistently higher in the distribution system than in the treated water. In Hearst, Ontario, for example, manganese concentrations in raw water, in treated water and in the distribution system (samples taken after a five-minute flush) were 0.023, 0.009 and 0.011 mg/L, respectively.Footnote 9

Industrial emissions containing manganese oxides are the principal source of manganese in the atmosphere. The total atmospheric emission of manganese from anthropogenic sources in Canada was estimated to be 1225 t in 1984; 78.5% of this originated from industrial processes, mainly related to metal alloy production. Emissions stemming from gasoline-powered motor vehicles accounted for a further 17.2%, whereas the remaining 4.3% of atmospheric manganese emissions were due to the burning of coal for power generation, solid waste incineration and pesticide application.Footnote 10

A study of the chemical composition of particulate matter over Edmonton, Alberta, between 1978 and 1979 showed a mean concentration of manganese in air of 0.071 g/m. Seasonal variation was considerable: in November 1978, the mean concentration was 0.050 g/m; in March/April and July/August 1979, the average concentrations were 0.065 g/m and 0.098 g/m, respectively. In a remote, non-urban site (Stony Plain Meteorological Station), the average concentration was <0.03 g/m during the same sampling periods. At both sites, the manganese is believed to be mainly of crustal origin.Footnote 11

In a 1982 survey across Ontario, the spatial pattern of concentrations of trace metals, including manganese, in precipitation and air was monitored.Footnote 12 A general decreasing trend in manganese concentrations from south to north was observed. The mean concentration of manganese in air ranged from 0.007 g/m3 in the south to 0.0029 g/m in the north. Similarly, the annual dry deposition of manganese ranged from 1.53 g/m in the south to 0.62 g/m in the north. The mean annual concentration of manganese in precipitation ranged from 0.0047 mg/L in the south to 0.0031 mg/L in the north.

Manganese is invariably present in arable soil.Footnote 13 The average manganese content of Canadian soil is 0.08 mg/g;Footnote 14 concentrations range from non-detectable to 7 mg/g.Footnote 15

Manganese is associated, in trace amounts, with every kind of plant and animal tissue.Footnote 13 The manganese content of foodstuffs varies considerably. Generally, low concentrations are found in dairy products (mean 0.12 mg/kg) and meats (mean 0.33 mg/kg).Footnote 16 Manganese is relatively evenly distributed throughout all of the food groups derived from plant sources (mean 2.66 mg/kg).Footnote 16 California wines analysed in Canada contained manganese at concentrations ranging from 0.18 to 1.64 mg/kg,Footnote 17 whereas manganese concentrations in carbonated beverages and fruit juices ranged from <0.01 to 0.03 mg/L and from 0.18 to 1.3 mg/L, respectively.Footnote 18

Canadian Exposure

In Canadian studies, daily dietary intake of manganese has been estimated to be 4.1 mgFootnote 19 and 3.3 mg.Footnote 16 A more recent estimate of average daily intake, calculated using data from Canadian per capita food consumption for 1981 and 1982Footnote 20 and literature values of the manganese content of the various dietary components,Footnote 16,Footnote 19,Footnote 21-26 was 4.7 mg (females 3.9 mg; males 5.6 mg).Footnote 27

If a daily water consumption of 1.5 L and a manganese concentration of 0.02 mg/L in the drinking water are assumed, the daily intake of manganese from Canadian drinking water would be approximately 0.03 mg. Actual daily intake of manganese from drinking water varies considerably, depending on the sampling area in Canada.

If an average concentration of manganese in air of 0.0001 mg/m and a daily respiratory volume of 20 m3 are assumed, the total daily intake of manganese through the respiratory tract would be 0.002 mg.

Based on the above figures, the total daily exposure of a Canadian to manganese from all environmental sources would be just over 4.7 mg. The greatest source of this exposure is from food. Intake from food is substantially higher than intake from drinking water, even in areas where the manganese content of water is high. In a 1975 study, the U.S. Environmental Protection Agency estimated total daily intake of manganese to be approximately 3 mg.Footnote 28

Analytical Methods and Treatment Technology

Manganese in water can be determined by atomic absorption spectrometry by direct aspiration into an air-acetylene flame (detection limit 0.01 mg/L). Alternatively, low concentrations can be determined by chelation with ammonium pyrrolidine dithiocarbamate, extraction into methyl isobutyl ketone and aspiration into an air-acetylene flame.Footnote 29

The removal of manganese from water supplies is often done in conjunction with iron removal. Manganese can be removed by the conventional treatment process of chlorination-filtration, at a pH of 8.4 or above.Footnote 30 It is difficult to remove manganese to achieve concentrations below 0.05 mg/L.

Health Considerations

Essentiality

Manganese is an essential element in humans and animals, functioning both as an enzyme co-factor and as a constituent of metalloenzymes. It has been implicated in carbohydrate metabolism, lipid and sterol metabolism and oxidative phosphorylation. Furthermore, experimental studies in animals suffering from manganese deficiency have suggested a role for manganese in the prevention of tissue damage following lipid peroxidation and in the normal functioning of the central nervous system.Footnote 31

Gross deficiencies of manganese have never been observed in the general population, but a recent experimental study involving human subjects fed a manganese-deficient diet (0.11 mg/d) resulted in the development of dermatitis and hypocholesterolaemia and elevated concentrations of serum calcium and phosphorus.Footnote 32

The Recommended Daily Intake (RDI) of manganese for Canadians has yet to be established. In a recent comprehensive literature survey of studies of manganese metabolism in humans, it was concluded that previous estimates for a safe and adequate daily dietary allowance for manganese (2.5-5.0 mg/d) were too low, and a new range of 3.5-7.0 mg/d was recommended for adults.Footnote 31 A statistical analysis of the metabolic studies showed that a daily manganese intake of approximately 5 mg is required to consistently maintain a positive balance.

Absorption, Distribution and Excretion

The main routes of absorption for manganese are the respiratory and gastrointestinal tracts; cutaneous absorption of inorganic manganese is negligible.Footnote 13 Organically bound manganese may be absorbed through the skin.Footnote 33

Manganese is absorbed in the small intestine by a high-affinity, low-capacity active transport mechanism.Footnote 34 In the young infant, absorption of manganese is very high, approaching 99% at birth;Footnote 35 absorption gradually decreases with age to around 5.5% in the adult.Footnote 36,Footnote 37 Absorption of manganese in humans is affected by a large number of dietary factors. At low manganese intake levels, manganese bioavailability is enhanced by ascorbic acid and by meat-containing diets but is inhibited by some dietary fibre sources.Footnote 31 Several metal ions -- in particular iron, magnesium and calcium -- are known to decrease the absorption and retention of manganese.Footnote 31 There is evidence that manganese uptake is higher from soft drinking water than from hard drinking water.Footnote 38

The total body burden of manganese in an adult human is between 10 and 20 mg.Footnote 39 Bones contain the highest amount, about 25% of the body burdenFootnote 40 ; most of this seems to be deposited in the inorganic portion of the bone, which acts as a buffer. Manganese also accumulates in tissues that are rich in mitochondria and endoplasmic reticulum; the principal sites of accumulation after the skeleton are the liver, skeletal muscle, connective tissue and intestine. On a concentration basis (g Mn/g tissue), the testes, liver, pancreas and kidneys are the tissues that accumulate the most manganese.Footnote 25

The regulation of manganese excretion seems to be the main homeostatic mechanism for manganese,Footnote 41 although there is some evidence that regulation of absorption can also occur.Footnote 42,Footnote 43 Endogenous manganese is excreted via the liver in bileFootnote 44 for eventual elimination in the faeces, with pancreatic and other intestinal secretions increasing when the biliary system is overloaded.Footnote 45 It is difficult to quantify biliary excretion routes, as reabsorption can occur; however, reabsorption appears to be lowFootnote 46 and may depend on the amount of calcium in the faeces.Footnote 47 Variations in dietary manganese have little effect on the small amount of manganese excreted in the urine.Footnote 48

There are relatively few data describing the rate of elimination of manganese from humans. In a recent study involving 14 subjects, it was shown that orally administered manganese was eliminated by two sequential processes with biological half-lives of 13 (range 6-30) and 34 (range 26-54) days, respectively.Footnote 49 Both the rate of excretion and the amount of manganese eliminated are influenced by a number of factors, including manganese intake, the iron status in the body, the influence of other dietary components and innate differences in the genetic make-up of the individual.

Toxic Effects

Manganese is regarded as one of the least toxic elements. Chronic ingestion experiments in rabbits, pigs and cattle at 1-2 mg/g dose levels showed no immediate effects other than a change in appetite and a reduction in the incorporation of iron into haemoglobin.Footnote 33 However, more recent experimental and epidemiological studies have shown that exposure to manganese can indeed lead to deleterious changes, some of which are referred to below.

In general, cations are more toxic than anions, and Mn2+ is more toxic than Mn3+.Footnote 50 The associated anion may affect the toxicity of manganese; the citrate ion, for example, is more toxic than the chloride ion. Toxicity varies not only with the valence state, but also with the route of administration and, when manganese is inhaled, with particle size.

Apart from acute "metal fume fever" caused by inhaled or swallowed manganese dioxide, toxicity in humans is usually the result of chronic inhalation of high concentrations of manganese in dusts from industrial sources.Footnote 51-56 The principal effects of long-term occupational exposure to inorganic manganese compounds are "manganese pneumonia" or pneumonitisFootnote 13 and, more commonly, manganism. The neurological manifestations and biochemical alterations due to manganism have been detailed by Donaldson and Barbeau.Footnote 57

Except for one isolated incident, manganese intoxication due to drinking water has not been documented. In 1941, the cause of an encephalitis-like disease in Japan was attributed to contaminated well water that had a manganese concentration of 14 mg/L; however, concentrations of other metals, especially zinc, were also excessive, and it was never unequivocally established whether the high concentration of manganese was solely responsible for the disease.Footnote 58 In another area of Japan, a manganese concentration of 0.75 mg/L in a drinking water supply had no apparent adverse effect on the health of its consumers.Footnote 52

A number of experimental studies have shown that exposure to manganese can cause deleterious effects on the male reproductive system. In rabbits, chronic parenteral administration of manganese resulted in degenerative changes to the seminiferous tubules, eventually leading to infertility.Footnote 59 Administration of Mn3O4 (hausmannite) at a concentration of 1050 ppm in the diet of mice resulted in retarded growth and weight gain of the testes, seminal vesicles and preputial glands.Footnote 60

In a recent epidemiological fertility study of Belgian workers exposed to manganese dust in a factory producing manganese oxide, sulphate and carbonate, it was found that the number of children born to exposed male workers (aged 16-35) was half that in a control group.Footnote 61

Questions have been raised in the literature regarding a possible link between manganese and human birth defects.Footnote 41,Footnote 62,Footnote 63 Manganese dust is reported to affect the behaviour of the offspring of mice exposed during gestation.Footnote 64

Manganese has been shown to be mutagenic in several microbial studiesFootnote 65,Footnote 66 as well as in human cell line studies.Footnote 67,Footnote 68

Manganese produces lymphosarcomasFootnote 69 and adenomasFootnote 70 in mice. However, there is no evidence that manganese exposure causes cancer in humans,Footnote 71 despite the often large occupational exposures.

Acceptable Daily Intake

No adverse health effects were noted in humans with the following daily manganese intakes:Footnote 39

Acceptable Daily Intake
  Average (mg) Range (mg)
Food 3.0 2.0-7.0
Water 0.005 0.0-1.0
Air 0.002 0.0-0.029

Other Considerations

The presence of manganese in drinking water supplies may be objectionable for a number of reasons unrelated to health. At concentrations exceeding 0.15 mg/L, manganese stains plumbing fixtures and laundry and causes undesirable tastes in beverages.Footnote 72 Oxidation of manganese ions in solution results in precipitation of manganese oxides and incrustation problems. Even at concentrations of approximately 0.02 mg/L, manganese may form coatings on water distribution pipes that may slough off as black precipitates.Footnote 73 The growth of certain nuisance organisms is also supported by manganese.Footnote 72,Footnote 74 The presence of "manganese" bacteria, which concentrate manganese, may give rise to taste, odour and turbidity problems in the distributed water.

Rationale

  1. Manganese is among the elements least toxic to mammals; only exposure to extremely high concentrations from human-made sources has resulted in adverse human health effects.
  2. At levels exceeding 0.15 mg/L, manganese stains plumbing fixtures and laundry and causes undesirable tastes in beverages. Even at concentrations as low as 0.02 mg/L, problems may be encountered; however, it is difficult to remove manganese to achieve concentrations below 0.05 mg/L.
  3. The aesthetic objective for manganese in drinking water is therefore =0.05 mg/L. Manganese at this recommended limit is not considered to represent a threat to health, and drinking water with much higher concentrations has been safely consumed. A maximum acceptable concentration has, therefore, not been set.

References

Footnote 1

Canadian Council of Resource and Environment Ministers (CCREM). Canadian water quality guidelines. Prepared by the Task Force on Water Quality Guidelines, March (1987).

Return to the first footnote 1 referrer

Footnote 2

Department of Energy, Mines and Resources. Manganese. In: Canadian minerals yearbook 1985. Mineral Report No. 34, Mineral Resources Branch, Ottawa (1986).

Return to the first footnote 2 referrer

Footnote 3

Rossman, R. and Callendar, E. Manganese nodules in Lake Michigan. Science, 162: 1123 (1968).

Return to the first footnote 3 referrer

Footnote 4

Cronan, D.S. and Thomas, R.L. Ferromanganese concretions in Lake Ontario. Can. J. Earth Sci., 7: 1346 (1970).

Return to the first footnote 4 referrer

Footnote 5

Harriss, R.C. and Troup, A.G. Freshwater ferromanganese concretions: chemistry and internal structure. Science, 166: 604 (1969).

Return to the first footnote 5 referrer

Footnote 6

Environment Canada. Detailed surface water quality data, Northwest Territories 1980-1981, Alberta 1980-1981, Saskatchewan 1980-1981, Manitoba 1980-1981. Inland Waters Directorate (1984).

Return to the first footnote 6 referrer

Footnote 7

Beamish, R.J. and Van Loon, J.L. Precipitation loading of acid and heavy metals to a small acid lake near Sudbury, Ontario. J. Fish. Res. Board Can., 34: 649 (1977).

Return to the first footnote 7 referrer

Footnote 8

National Water Quality Data Bank (NAQUADAT). Water Quality Branch, Inland Waters Directorate, Environment Canada (1976).

Return to the first footnote 8 referrer

Footnote 9

Ontario Ministry of the Environment. Drinking water monitoring data (unpublished) (1987).

Return to the first footnote 9 referrer

Footnote 10

Jaques, A.P. National inventory of sources and emissions of manganese (1984). EPS 5/MM/1, Environment Canada (1987).

Return to the first footnote 10 referrer

Footnote 11

Klemm, R.F. and Gray, J.M.L. A study of the chemical composition of particulate matter and aerosols over Edmonton. Report RMD 82/9, prepared for the Research Management Division by the Alberta Research Council. 125 pp. (1982).

Return to the first footnote 11 referrer

Footnote 12

Chan, W.H., Tang, A.J.A., Chung, D.H.S. and Lusis, M.A. Concentration and deposition of trace metals in Ontario -- 1982. Water Air Soil Pollut., 29: 373 (1986).

Return to the first footnote 12 referrer

Footnote 13

Rodier, J. Manganese poisoning in Moroccan miners. Br. J. Ind. Med., 12: 21 (1955).

Return to the first footnote 13 referrer

Footnote 14

Warren, H.C. Some trace element concentrations in various environments. In: Environmental medicine. G.M. Howe and J.A. Lorraine (eds.). William Heinemann Medical Books, London, UK. p. 9 (1973).

Return to the first footnote 14 referrer

Footnote 15

Moran, J.B. The environmental implications of manganese as an alternate antiknock. Research Triangle Park, NC (1975).

Return to the first footnote 15 referrer

Footnote 16

Kirkpatrick, D.C. and Coffin, D.E. The trace metal content of representative Canadian diets in 1970 and 1971. Can. Inst. Food Sci. Technol. J., 7: 56 (1974).

Return to the first footnote 16 referrer

Footnote 17

Noble, A.C., Orr, B.H., Cook, W.G. and Campbell, J.L. Trace element analysis of wine by proton induced X-ray fluorescence spectrometry. J. Agric. Food Chem., 24: 532 (1976).

Return to the first footnote 17 referrer

Footnote 18

Mranger, J.C. The heavy metal content of fruit juices and carbonated beverages by atomic absorption. Bull. Environ. Contam. Toxicol., 5: 271 (1970).

Return to the first footnote 18 referrer

Footnote 19

Mranger, J.C. and Smith, D.C. The heavy metal content of a typical Canadian diet. Can. J. Public Health, 63: 53 (1972).

Return to the first footnote 19 referrer

Footnote 20

Department of National Health and Welfare. Recommended nutrient intakes for Canadians. Ottawa (1983).

Return to the first footnote 20 referrer

Footnote 21

Guthrie, B.E. and Robinson, M.F. Daily intakes of manganese, copper, zinc and cadmium by New Zealand women. Br. J. Nutr., 38:55 (1977).

Return to the first footnote 21 referrer

Footnote 22

Hamilton, E.I. and Minski, M.J. Abundances of the chemical elements in man's diet and possible relations with environmental factors. Sci. Total Environ., 1: 375 (1973).

Return to the first footnote 22 referrer

Footnote 23

Schlage, C. and Wortberg, B. Manganese in the diet of healthy preschool and school children. Acta Paediatr. Scand., 27: 648 (1972).

Return to the first footnote 23 referrer

Footnote 24

Shiraishi, K., Kawamura, H. and Tanaka, G.I. Daily intake of elements as estimated from analysis of total diet samples in relation to reference Japanese man. J. Radiat. Res., 27: 121 (1986).

Return to the first footnote 24 referrer

Footnote 25

International Commission on Radiological Protection. Report No. 23: Report of the Task Group on Reference Man. Pergamon Press, Oxford, UK. 411 pp. (1984).

Return to the first footnote 25 referrer

Footnote 26

Soman, S.D., Panday, V.K., Joseph, K.T. and Raut, S.R. Daily intake of some major and trace elements. Health Phys., 17: 35 (1969).

Return to the first footnote 26 referrer

Footnote 27

Hill, R.J. Review of information on manganese and the oxidation products of MMT combustion (unpublished). Prepared for the Department of National Health and Welfare, Ottawa (1988).

Return to the first footnote 27 referrer

Footnote 28

U.S. Environmental Protection Agency. Scientific and technical assessment report on manganese. National Environmental Research Center, Research Triangle Park, NC (1975).

Return to the first footnote 28 referrer

Footnote 29

American Public Health Association/American Water Works Association/Water Pollution Control Federation. Standard methods for the examination of water and wastewater. 16th edition. American Public Health Association, Washington, DC (1985).

Return to the first footnote 29 referrer

Footnote 30

Wong, J.M. Chlorination-filtration for iron and manganese removal. J. Am. Water Works Assoc., 76(1): 76 (1984).

Return to the first footnote 30 referrer

Footnote 31

Zidenberg-Cherr, S. and Keen, C.L. Enhanced tissue lipid peroxidation: mechanism underlying pathologies associated with dietary manganese deficiency. In: Nutritional bioavailability of manganese. C. Kies (ed.). American Chemical Society, Washington, DC. p. 56 (1987).

Return to the first footnote 31 referrer

Footnote 32

Friedman, B.J., Freeland-Graves, J.H., Bales, C.W., Behmardi, F., Shorey-Kutschke, R.L., Willis, R.A., Crosby, J.B., Tricket, P.C. and Houston, S.D. Manganese balance and clinical observations in young men fed a manganese-deficient diet. J. Nutr., 117: 133 (1987).

Return to the first footnote 32 referrer

Footnote 33

National Research Council, Committee on Medical and Biologic Effects of Environmental Pollutants. Manganese. National Academy of Sciences, Washington, DC (1973).

Return to the first footnote 33 referrer

Footnote 34

Garcia-Aranda, J.A., Wapnir, R.A. and Lifshitz, F. In vivo intestinal absorption of manganese in the rat. J. Nutr., 113: 2601 (1983).

Return to the first footnote 34 referrer

Footnote 35

Zlotkin, S.H. and Buchanan, B.E. Manganese intakes in intravenously fed infants. Biol. Trace Element Res., 9: 271 (1986).

Return to the first footnote 35 referrer

Footnote 36

Crounse, R.G., Pories, W.J., Bray, J.T. and Manger, R.L. Geochemistry and man: health and disease. 1. Essential elements. In: Applied environmental geochemistry. I. Thornton (ed.). Academic Press, New York, NY. p. 267 (1983).

Return to the first footnote 36 referrer

Footnote 37

Sandstrm, B., Davidsson, L., Cederblad, A. and Lnnerdal, B. A method for studying manganese absorption in humans. Fed. Proc., 46:570 (1987).

Return to the first footnote 37 referrer

Footnote 38

Ingols, R.S. and Craft, T.F. Analytical notes: hard- vs soft-water effects on the transfer of metallic ions from intestine. J. Am. Water Works Assoc., 68: 209 (1976).

Return to the first footnote 38 referrer

Footnote 39

Schroeder, H.A., Balassa, J.J. and Tipton, I.H. Essential trace metals in man: manganese. A study in homeostasis. J. Chronic Dis., 19:545 (1966).

Return to the first footnote 39 referrer

Footnote 40

Hurley, L.S. and Keen, C.L. Manganese. In: Trace elements in human and animal nutrition. 5th edition. W. Mertz (ed.). Academic Press, San Diego, CA (1987).

Return to the first footnote 40 referrer

Footnote 41

Saner, G., Dagoglu, T. and Ozden, T. Hair manganese concentrations in newborns and their mothers. Am. J. Clin. Nutr., 41:1042 (1985).

Return to the first footnote 41 referrer

Footnote 42

World Health Organization. Environmental health criteria for manganese. April, Geneva (1975).

Return to the first footnote 42 referrer

Footnote 43

Abrams, E., Lassiter, J.W., Miller, W.J., Neathery, M.W., Gentry, R.P. and Blackmon, D.N. Effect of normal and high manganese diets on the role of bile in manganese metabolism in calves. J. Anim. Sci., 45: 1108 (1977).

Return to the first footnote 43 referrer

Footnote 44

Greenberg, D.M., Copp, D.H. and Cuthbertson, E.M. The distribution and excretion, particularly by way of the bile, of iron, cobalt, and manganese. J. Biol. Chem., 147: 749 (1943).

Return to the first footnote 44 referrer

Footnote 45

Bertinchamps, A.J., Millar, S.T. and Cotzias, G.C. Interdependence of routes excreting manganese. Am. J. Physiol., 211: 217 (1966).

Return to the first footnote 45 referrer

Footnote 46

Solomons, N.W. The other trace minerals; manganese, molybdenum, vanadium, nickel, silicon, and arsenic. In: Absorption and malabsorption of mineral nutrients. N.W. Solomons and I.H. Rosenberg (eds.). Alan R. Liss, New York, NY (1984).

Return to the first footnote 46 referrer

Footnote 47

Van Barneveld, A.A. and Van den Hamers, C.J.A. The influence of calcium and magnesium on manganese transport and utilization in mice. Biol. Trace Element Res., 6: 489 (1984).

Return to the first footnote 47 referrer

Footnote 48

Hine, C.H. and Pasi, A. Manganese intoxication. West. J. Med., 123: 101 (1975).

Return to the first footnote 48 referrer

Footnote 49

Sandstrm, B., Davidsson, L., Cederblad, A., Eriksson, R. and Lnnerdal, B. Manganese absorption and metabolism in man. Acta Pharmacol. Toxicol., 59(7): 60 (1986).

Return to the first footnote 49 referrer

Footnote 50

Smith, R.G. In: Metallic contaminants and human health. D.H.K. Lee (ed.). Academic Press, New York, NY (1972).

Return to the first footnote 50 referrer

Footnote 51

Schuler, P., Oyanguren, H., Maturana, V., Valenzuela, A., Cruz, R., Plaza, V., Schmidt, E. and Haddad, R. Manganese poisoning. Ind. Med. Surg., 26: 167 (1957).

Return to the first footnote 51 referrer

Footnote 52

Suzuki, T. Manganese pollution of the environment. Ind. Med. (Sangyo Igaku-Japan), 12: 529 (1970).

Return to the first footnote 52 referrer

Footnote 53

Cotzias, G.C., Papavasiliou, P.S., Ginos, J.P., Steck, A. and Duby, S. Metabolic modification of Parkinson's disease and of chronic manganese poisoning. Annu. Rev. Med., 22: 305 (1971).

Return to the first footnote 53 referrer

Footnote 54

Emara, A.M., El'Ghawabi, S.H., Madkour, O.I. and El'Samna, G.H. Chronic manganese poisoning in the dry battery industry. Br. J. Ind. Med., 28: 78 (1971).

Return to the first footnote 54 referrer

Footnote 55

Jonderko, G., Kujawska, A. and Langauer-Lewowicka, H. Problems of chronic manganese poisoning on the basis of investigations of workers at a manganese alloy foundry. Int. Arch. Arbeitsmed., 28: 250 (1971).

Return to the first footnote 55 referrer

Footnote 56

Rosenstock, H.A., Simons, D.G. and Meyer, J.S. Chronic manganism. Neurologic and laboratory studies during treatment with levodopa. J. Am. Med. Assoc., 217: 1354 (1971).

Return to the first footnote 56 referrer

Footnote 57

Donaldson, J. and Barbeau, A. Manganese neurotoxicity: possible clues to the etiology of human brain disorders. Met. Ions Neurol. Psychiatry, 15: 259 (1985).

Return to the first footnote 57 referrer

Footnote 58

World Health Organization. Environmental health criteria programme for manganese and its compounds. Japanese report (1974).

Return to the first footnote 58 referrer

Footnote 59

Chandra, S. and Tandon, S.K. Enhanced manganese toxicity in iron-deficient rats. Environ. Physiol. Biochem., 4: 16 (1974).

Return to the first footnote 59 referrer

Footnote 60

Gray, L.E. and Laskey, J.W. Multivariant analysis of the effects of manganese on the reproductive physiology and behaviour of the male house mouse. J. Toxicol. Environ. Health, 6: 861 (1980).

Return to the first footnote 60 referrer

Footnote 61

Lauwerys, R., Roels, H., Genet, P., Toussaint, G., Bouckaert, A. and De Cooman, S. Fertility of male workers exposed to mercury vapor or to manganese dust: a questionnaire study. Am. J. Ind. Med., 7:171 (1985).

Return to the first footnote 61 referrer

Footnote 62

Marienfeld, C.L. and Collins, M. The ebb and flow of manganese. A possible pathogenic factor in birth defects, cancer and heart disease. Trace Substances Environ. Health, 15: 3 (1981).

Return to the first footnote 62 referrer

Footnote 63

Gol'dina, I.R., Nadeenko, V.G., Salchenko, S.P., D'Yachenko, O.Z., Senchenko, V.G. and Vasalygina, V.V. Toxicological evaluation of manganese during intake in drinking water. Gig. Sanit., II: 80 (1984) [Nutr. Abstr. Rev., 55: 6416 (1985)].

Return to the first footnote 63 referrer

Footnote 64

Massaro, E.J., D'Agostino, R.B., Stineman, C.H., Morganti, J.B. and Lown, B.A. Alterations in behaviour of adult offspring of female mice exposed to MnO2 dust during gestation. Fed. Proc., 39: 623 (1980).

Return to the first footnote 64 referrer

Footnote 65

Demeric, M. and Hanson, J. Mutagenic action of manganous chloride. Cold Spring Harbor Symp. Quant. Biol., 16: 215 (1951).

Return to the first footnote 65 referrer

Footnote 66

Putrament, K.A., Baranowska, H. and Prazmo, W. Induction by manganese of mitochondrial antibiotic resistance mutations in yeast. Mol. Gen. Genet., 126: 357 (1973).

Return to the first footnote 66 referrer

Footnote 67

Linn, S., Kairis, M. and Holliday, R. Decreased fidelity of DNA polymerase activity isolated from aging human fibroblast. Proc. Natl. Acad. Sci. U.S.A., 73: 2818 (1976).

Return to the first footnote 67 referrer

Footnote 68

Seal, G., Shearman, C.W. and Loel, L. Studies with human placenta DNA polymerases. J. Biol. Chem., 254: 5229 (1979).

Return to the first footnote 68 referrer

Footnote 69

DiPaslo, J.A. The potentiation of lymphosarcomas in the mouse by manganous chloride. Fed. Proc., 23: 393 (1964).

Return to the first footnote 69 referrer

Footnote 70

Stoner, G.D., Shimkin, M.B., Troxell, M.C., Thompson, T.L. and Terry, L. Test for carcinogenicity of metallic compounds by the pulmonary tumor response in strain A mice. Cancer Res., 36: 1744 (1976).

Return to the first footnote 70 referrer

Footnote 71

Costa, M., Kraker, A.J. and Paterns, R. Toxicity and carcinogenicity of essential and non-essential metals. In: Progress in clinical biochemistry and medicine. Springer-Verlag, Berlin (1984).

Return to the first footnote 71 referrer

Footnote 72

Griffin, A.E. Significance and removal of manganese in water supplies. J. Am. Water Works Assoc., 52: 1326 (1960).

Return to the first footnote 72 referrer

Footnote 73

Bean, E.L. Potable water-quality goals. J. Am. Water Works Assoc., 66: 221 (1974).

Return to the first footnote 73 referrer

Footnote 74

Wolfe, R.S. Microbial concentration of iron and manganese in water with low concentrations of these elements. J. Am. Water Works Assoc., 52: 1335 (1960).

Return to the first footnote 74 referrer