AMMONIUM SULFATE CAS N°: 7783-20-2

OECD SIDS
AMMONIUM SULFATE
Conclusion
Nitrification during sewage treatment plant operation involves both sensitive (no growth at 4700 but
growth at 94 mg/l ammonium sulfate) and insensitive (growth at 4700 mg/l ammonium sulfate)
strains of Nitrobacter spp (Suwa et al., 1994). This indicates that a NOEC for specific nitrifying
bacteria will be greater than 94 mg/l.
Nitrogen fixation and total soil biomass (but not soil base respiration rate) can be affected by
ammonium sulfate applied at 82.5 kg/ha or more.
4.2 Terrestrial Effects
Toxicity to terrestrial plants
Valid test results are available for four plant species exposed to excessive amounts of ammonium
sulfate. In two examples ammonium sulfate is applied in solid form, while in the others the
application is from aqueous solution and as an atmospheric aerosol.
The effect of ammonium sulfate solution on seed germination was studied for Avena sterilis spp
macrocarpa Mo, in a 21 day test (Gonzalez Ponce and Salas, 1989). Seeds were wrapped with filter
paper which was wetted with ammonium sulfate-solutions of 100 to 5000 mg/l. No significant
increase in germination was found up to 2500 mg/l, compared with the control. An inhibitory effect
was found at 5000 mg/l ammonium sulfate probably caused by a salt effect.
The effect of ammonium sulfate addition on the growth of the onion Allium cepa L. has been
studied under laboratory conditions in 4 Canadian soils, in the presence of lime to raise the soil pH
to approximately 6.5 (Abbés et al., 1995). After 84 days in a growth chamber, immature plants were
harvested and fresh and dry weight of all plant parts were determined. Yield was greatest for
626 mg ammonium sulfate / kg soil (calculated from 133 mg N / kg soil). An inhibitory effect was
found at 1880 and 2506 mg ammonium sulfate / kg soil (calculated from 399 and 532 mg N / kg
soil), except for the sandy soil where only 2506 mg ammonium sulfate / kg soil was inhibitory. In
general such observations could be explained by salt effects.
14 day old pinto bean plants (Phaseolus vulgaris L.) exposed to 26 mg/m 3 ammonium sulfate
aerosol for up to 320 hours (ca. 13 days) in an environmental growth chamber showed no changes
in plant biomass or leaf area. However, visible foliar injury occurred, and both abaxial and adaxial
leaf resistances were decreased from control values (Gmur, Evans and Cunningham, 1983). The
ammonium sulfate application rate is stated to be about 2 orders of magnitude above ambient
episode concentration.
The 6 year effect of ammonium sulfate spread as a solid fertilizer was investigated in a stand of
trees (Picea abies, 12 years old at the beginning of the test) in southern Sweden (Rosengren-Brinck
and Nihlgard, 1995). Spreading at 471 kg ammonium sulfate (calculated from 100 kg N) per ha per
year affected resistance to drought, which was evident in a reduction in the flushing of new shoots.
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