Data bank of environmental chemicals     |     The Finnish Environment Institute (SYKE)


Data bank of environmental properties of chemicals

CAS-number :
Synonyms :
Benzenamine, N,N-dimethyl-
Sumformula of the chemical :
EINECS-number :
Uses :
Dyes, intermediates, solvent, manufacture of vanillin,
stabilizer (acid acceptor), reagent.
State and appearance :
Yellowish to brownish, oily liquid.
Molecular weight :
Spesicif gravity (water=1) :
Vapor density (air=1) :
Conversion factor, 1 ppm in air=_mg/m3 :
5.04  mg/m3
Conversion factor, 1 mg/m3 in air=_ppm :
0.2  ppm
Vapor pressure, mmHg :
29.5 °C
0.5  20 °C
Water solubility, mg/l :
1400  MITI 1992
Melting point, °C :
1.9  > 1.9, MITI 1992
Boiling point, °C :
192.5  192.5 - 193.5 °C
192.5  MITI 1992
Flashing point, °C :
62.7  (closed cup)
pKa :
5.15  25°C
5.1  Sangster 1989
Log octanol/water coefficient, log Pow :
2.3  ANON 1986
2.5  Anon 1988
2.62  measured, Sax 1986
2.31  Sangster 1989
Henry's law constant, Pa x m3/mol :
6.8  Anon 1988
Mobility :
Equilibrium distribution:
        mass %
air     69.02
water   29.55
solid    1.43
(Anon 1988)
Other physicochemical properties :
Soluble in alcohol and ether; insoluble in water; autoign
temperature 370 °C. 

Moderate fire hazard when exposed to heat, flame, or oxidation. 
When heated to decomposition it emits highly toxic fumes of
aniline; it can react with oxidizing materials.
Photochemical degradation in air :
Photooxidation half-life in air:
21hr - 2.7hr, based upon measured rate data for hydroxyl 
radicals and ozone (Howard 1991).
Photochemical degradation in water :
Flash photolysis of air-saturated aqueous solutions of
N,N-dimethylaniline was examined at different pH values. 
on visual assessment, highly colored permanent products were
observed at pH values ranging between 2.6 and 6.3. 
No colored
products were observed at pH 1.6. 
With nitrogen-saturated
solutions, the formation of these highly colored products was
not observed (Sax 1986).

Photooxidation half-life in water:
80.2d - 0.8d, based upon measured rate data for singlet oxygen 
in aqueous solution (Howard 1991).
Oxidation-reduction reactions :
The reactivity of N,N-dimethylaniline, as well as other
compounds, with OH radicals in aqueous solution was compiled.

The specific rate constant was reported as 5.3E+09/M sec. 
temperature between 15 - 25 °C, pH was 9.0, and the method of
detection was PNDA (Sax 1986).
Half-life in air, days :
0.86  21hr - 2.7hr,
0.11  based upon photooxidation half-life in air.
  Howard 1991
Half-life in soil, days :
180  6mo - 4w,
28  scientific judgement based upon estimated unacclimated aqueous aerobic biodegradation half-life.
  Howard 1991
Half-life in water, days :
2.3  in Rhine river water, Sax 1986
80.2  80.2d - 0.8d,
0.8  in surface water: based upon photooxidation half-life in water.
360  12mo - 8w,
56  in ground water: scientific judgement based upon estimated unacclimated aqueous aerobic biodegradation half-life.
  Howard 1991
Aerobic degradation in water :
Aerobic half-life:
6mo - 4w, scientific judgement based upon unacclimated aqueous 
screening test data (Howard 1991).
Anaerobic degradation in water :
Anaerobic half-life:
2yr - 16w, scientific judgement based upon estimated 
unacclimated aqueous aerobic biodegradation half-life (Howard 
Total degradation in water :
1.9% by BOD
period: 14d
substance: 100 mg/l
sludge: 30 mg/l
(MITI 1992)
Ready biodegradability :
Confirmed to be non-biodegradable (Anon. 1987).
Other information of degradation :
Biodegradation of N,N-dimethylaniline by activated sludge
samples has been examined. 
Activated sludge samples were chosen
from two treatment facilities that accepted domestic and
industrial discharges. 
Sludges (3 ml) were dosed with 3 ml of
N,N-DMA (final concentration of N,N-DMA = 20 mg/l) and
incubated for 6 hr at 25 °C. 
The concentration of N,N-DMA after
incubation was determined by GLC or colorimetry. 
To distinguish
bacterial degradation from other types, some of the sludge
samples were sterilized by autoclave prior to incubation.

Results: The average depletion of N,N-DMA from activated sludge
samples was 1 % and the depletion range was 0 to 3 % (Sax 1986).
Bioconcentration factor, fishes :
5.4  5.4 - 13.6, 6w, Cyprinus caarpio, conc 0.5 mg/l,
4.7  4.7 - 10.1, 6w, Cyprinus carpio, conc 0.05 mg/l,
10.1  MITI 1992
Other information of bioaccumulation :
Confirmed to be non-accumulative or low accumulative (Anon.
LD50 values to mammals in oral exposure, mg/kg :
990  orl-rat, Sax 1986
1410  orl-rat
LD50 values to mammals in non-oral exposure , mg/kg :
1700  dermal-rbt, Sax 1986
LDLo values to mammals in oral exposure, mg/kg :
50  orl-hmn, Sax 1986
Health effects :
Readily absorbed through skin and lungs (Sax 1986).

Skin and eye irritation data: skn, rbt, 10 mg, 24 hr, open,
mild (Sax 1986).
LC50 values to fishes, mg/l :
65.6  96hr, Pimephales promelas
  Broderius & Kahl 1985
102  48hr, Oryzias latipes, MITI 1992
78.2  96 hr, Pimephales promelas
52.6  96 hr, Pimephales promelas, Brooke et al. 1984
EC50 values to fishes, mg/l :
75.2  96 hr, mbt, Pimephales promelas
52.6  96 hr, mbt, Pimephales promelas, Brooke et al. 1984
Other information of water organisms :
EC50 110 mg/l, 24hr, rpd, Tetrahymena pyriformis (Yoshioka et al.

2357Anon 1988. Concentrations of industrial organic chemicals measured in the environment: The influence of physico - chemical properties, tonnage and use pattern. Technical report no 29. European chemical industry ecology & toxicology centre, ECETOC. pp. 105.
1848Anon. 1987a. The list of the existing chemical substances tested on biodegradability by microorganisms or bioaccumulation in fish body by Chemicals Inspection & Testing Institute. Ministry of International Trade and Industry, MITI. Japan.
2283Anon.1986a. Evaluation of the OECD laboratory intercomparison testing on the determination of the partition coefficient n-octanol-water by reverse phase HPLC. Report. Fraunhofer-Institut für Umweltchemie und Ökotoxikologie.
190Broderius, S. & Kahl, M. 1985. Acute toxicity of organic chemical mixtures to the fathead minnow. Aquatic Toxicol. 6: 307-322.
3295Brooke, L. T. et al. 1984. Acute toxicities of organic chemicals to fathead minnows (Pimephales promelas); Vol 1. Center for Lake Superior Environmental Studies University of Wisconsin-Superior, Superior, Wisconsin, U.S.A.
3120Howard, P.H., Boethling, R.S., Jarvis, W.F., Meylan, W.M. & Michalenko, E.M., Handbook of Environmental Degradation Rates, 1991. Lewis Publicers, Inc., Chelsea, Michigan, U.S.A., pp. 725.
3105MITI 1992. Biodegradation and bioaccumulation data of existing chemicals based on the CSCL Japan. Compild under the Safety Division Basic Industries Bureau Ministry of International Trade & Industry, Japan. Edited by Chemicals Inspection & Testing Institute, Japan.
3104Sangster, J. 1989. Octanol-water partition coefficients of simple organic compounds. J. Phys. Chem. Ref. Data, Vol 18, No. 3: 1111 - 1229.
2147Sax, I. 1986. Hazardous chemicals information annual No. 1. Van Nostrand Reinhold Information Services, New York. 766 s.
1766Yoshioka, Y., Ose, Y. & Sato,T. 1985. Testing the toxicity of chemicals with Tetrahymena pyriformis. Sci. Total. Environ. 43:149.

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