are there any developmental disorders associated with it?
Yes - short-term memory, visual identification, diminished IQ scores
Manganese
Several recent studies attempt to examine the effects of chronic low-dose manganese overexposure on child development. The earliest study was conducted in the Chinese province of Shanxi. Drinking water there had been contaminated through improper sewage irrigation and contained 240–350 µg Mn/L. Although Mn concentrations at or below 300 µg Mn/L were considered safe at the time of the study by the US EPA and 400 µg Mn/L by the World Health Organization, the 92 children sampled (between 11 and 13 years of age) from this province displayed lower performance on tests of manual dexterity and rapidity, short-term memory, and visual identification, compared to children from an uncontaminated area. More recently, a study of 10-year-old children in Bangladesh showed a relationship between Mn concentration in well water and diminished IQ scores. A third study conducted in Quebec examined school children between the ages of 6 and 15 living in homes that received water from a well containing 610 µ
in which of the following does manganese have the highest oxidation number Manganese compounds where manganese is in oxidation state +7, which are mostly restricted to the unstable oxide MnO, compounds of the intensely purple permanganate anion MnO, and a few oxyhalides (MnOF and MnOCl), are powerful oxidizing agents.
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Manganese [SEP] Childhood developmental disorders
Several recent studies attempt to examine the effects of chronic low-dose manganese overexposure on child development. The earliest study was conducted in the Chinese province of Shanxi. Drinking water there had been contaminated through improper sewage irrigation and contained 240–350 µg Mn/L. Although Mn concentrations at or below 300 µg Mn/L were considered safe at the time of the study by the US EPA and 400 µg Mn/L by the World Health Organization, the 92 children sampled (between 11 and 13 years of age) from this province displayed lower performance on tests of manual dexterity and rapidity, short-term memory, and visual identification, compared to children from an uncontaminated area.