Spacecraft Water Exposure Guidelines for Selected Contaminants Volume 2 (2007) / Chapter Skim
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Appendix 2 Ammonia
Appendix 2 Ammonia
Pages 39-51
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From page 39... ...
phase of the Lunar Mars Life Support Test (LMLST) , the venting of headspace gases from the bioreactor and wastewater containers caused an increase in the airborne ammonia.
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From page 40... ...
Absorption Bacteria in the digestive tract produce ammonium ions (NH4+) from the metabolism of nitrogen-containing compounds that come from in TABLE 2-2 Ammonia in Water Samplesa Vehicle or Habitat Type of sample Typical Concentration Reference Mir space station Humidity 3-15 mg/L Pierre et al.
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From page 41... ...
. In people with normal renal function, an increase in dietary protein causes a decrease in the retention of ammonium hydroxide (15N)
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From page 42... ...
TOXICITY SUMMARY A small number of animal toxicity studies conducted mostly on rodents, suggest that ingested ammonia causes little, if any, systemic toxicity. Exposures at 40 mg/kg/d and above seem necessary to cause any adverse effects, and this dosage should be considered a lowest-observedadverse-effect level (LOAEL)
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From page 43... ...
Reprinted with permission; copyright 1988, Raven Press, New York. studies are targeted at understanding the neurologic effects of high concentrations of ammonia in the blood as seen in liver failure; however, massive oral doses are necessary to increase and sustain these concentrations in healthy test animals.
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From page 44... ...
In adults, only those with symptoms after ingesting strong alkali compounds and other caustic material are at risk for complications, the most common of which is esophageal injury. Thus, systemic injury from ingested ammonia is unlikely for one-time, large aqueous doses.
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From page 45... ...
In a much more limited study, Uzvolgyi and Bojan (1980, 1985) found that neither ammonia alone nor diethyl pyrocarbonate alone caused an increase in lung tumors when given to female Kid: CFLP mice in gavage doses twice per wk for 4 wk, but when the two were given together, more than half the mice showed lung tumors.
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From page 46... ...
There is one report that 22 workers exposed to ammonia gas at a fertilizer factory had an increase in chromosomal aberrations and sister chromatid exchanges (Yadav and Kaushik 1997)
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From page 47... ...
The most recent Agency for Toxic Substances and Disease Registry (ATSDR 2004) toxicologic profile for ammonia does not list an oral minimal risk level (MRL)
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From page 48... ...
. From a strictly toxicologic perspective, that amount would seem to be safe; however, the average odor threshold for ammonia in water is only 1.5 mg/L (Amoore and Hautla 1983)
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From page 49... ...
1983. Odor threshold as an aid to chemical safety: Odor thresholds compared with threshold limit values and volatilities from 214 industrial chemicals in air and water dilution.
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1995. Prenatal exposure of rats to ammonia impairs NMDA receptor function and affords delayed protection against ammonia toxicity and glutamate neurotoxicity.
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From page 51... ...
Report dated January 9, 2002. Subject: Final chemical analysis results for the STS-104/7A ISS water samples.
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