N,N-dimethylaniline

121-69-7

Dyes, intermediates, solvent, manufacture of vanillin,
stabilizer (acid acceptor), reagent.

Yellowish to brownish, oily liquid.

121

Equilibrium distribution:
        mass %
air     69.02
water   29.55
solid    1.43
(Anon 1988)

Soluble in alcohol and ether; insoluble in water; autoign
temperature 370 °C. 
Combustible.

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.

Photooxidation half-life in air:
21hr - 2.7hr, based upon measured rate data for hydroxyl 
radicals and ozone (Howard 1991).

Flash photolysis of air-saturated aqueous solutions of
N,N-dimethylaniline was examined at different pH values. 
Based
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).

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. 
The
temperature between 15 - 25 °C, pH was 9.0, and the method of
detection was PNDA (Sax 1986).

Aerobic half-life:
6mo - 4w, scientific judgement based upon unacclimated aqueous 
screening test data (Howard 1991).

Anaerobic half-life:
2yr - 16w, scientific judgement based upon estimated 
unacclimated aqueous aerobic biodegradation half-life (Howard 
1991).

Biodegradation:
1.9% by BOD
period: 14d
substance: 100 mg/l
sludge: 30 mg/l
(MITI 1992)

Confirmed to be non-biodegradable (Anon. 1987).

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).

Confirmed to be non-accumulative or low accumulative (Anon.
1987).

Readily absorbed through skin and lungs (Sax 1986).

Skin and eye irritation data: skn, rbt, 10 mg, 24 hr, open,
mild (Sax 1986).

EC50 110 mg/l, 24hr, rpd, Tetrahymena pyriformis (Yoshioka et al.
1985).