Manganese dinitrate

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics

Type of information:

other: review article

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Recent peer reviewed summary of available toxicological and adverse health effect informaiton for manganese

Data source

Reference

Reference Type:

review article or handbook

Title:

TOXICOLOGICAL PROFILE FOR MANGANESE

Author:

Williams, M, McClure, PR

Year:

2012

Bibliographic source:

Agency for Toxic Substances and Disease Registry, U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Materials and methods

Principles of method if other than guideline:

No guideline required

GLP compliance:

not specified

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:

Manganese is required by the body and is found in virtually all diets. Adults consume between 0.7 and 10.9 mg of manganese per day in the diet, with higher intakes for vegetarians who may consume a larger proportion of manganese-rich nuts, grains, and legumes than non-vegetarians. Manganese intake from drinking water is substantially lower than intake from food. Following inhalation exposure, manganese can be transported into olfactory or trigeminal presynaptic nerve endings in the nasal mucosa with subsequent delivery to the brain, across pulmonary epithelial linings into blood or lymph fluids, or across gastrointestinal epithelial linings into blood after mucociliary elevator clearance from the respiratory tract.

Details on distribution in tissues:

Manganese is found in the brain and all other mammalian tissues, with some tissues showing higher accumulations of manganese than others. For example, liver, pancreas, and kidney usually have higher manganese concentrations than other tissues.

Details on excretion:

The principal route of elimination of manganese from the body is fecal elimination via hepatobiliary excretion; contributions from pancreatic, urinary, and lactational elimination are expected to be small. Excess manganese is expected to be eliminated from the body rapidly.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): low bioaccumulation potential based on study results
Even though daily dietary intake of manganese can vary substantially, adult humans generally maintain stable tissue levels of manganese through the regulation of gastrointestinal absorption and hepatobiliary excretion. Evidence from studies in humans indicates that inhalation exposure to high levels of manganese compounds (usually manganese dioxide, but also compounds with Mn(II) and Mn(III)) can lead to a disabling syndrome of neurological effects referred to as ‘manganism.