Methanol

67-56-1

Solvent.

Quality: sour, sharp
Hedonic tone: neutral
Threshold odour concentration
absolute: 4.26 ppm
50 % recognition: 53.3 ppm
100 % recognition: 53.3 ppm
Odour index 100 % recognition: 2 393
(Hellman & Small 1974)

32.04

Relative volatility (nBuAc=1) = 5.90

The value of Henry's law constant indicates that volatilization
from environmental waters may be significant (Lyman et al. 1982)

The volatilization half-life from a model river has been
estimated to be 5.3 hr (Lyman et al. 1982).

The volatilization half-life from an environmental pond has
been estimated to be 2.6 days (USEPA 1987).

Methanol is miscibility in water and low octanol/water
partition coefficient suggest high mobility in soil
(Howard 1990).

Miscible. 
(Merck Index 1983)

Methanol is expected to exist almost entirely in the vapor
phase in the ambient atmosphere, based on its vapor pressure.

It is degraded by reaction with photochemically produced
hydroxyl radicals with estimated half-life 17.8 days in a
typical ambient atmosphere. 
Atmospheric methanol can also react
with nitrogen dioxide in polluted air to yield methyl nitrite
(Howard 1990).

Photooxidation half-life in air:
71hr - 713hr,
based uponmeasured rate data for the vapor phase reaction with
hydroxyl radicals in air (Howard 1991).

Sediment an clay suspensions solution did not photocatalyze the
degradation of methanol in aqueous solution during irradiation
with UV light (Oliver et al. 1979).

Methanol in aqueous solution exhibited no degradation when
exposed to sunlight using an EPA test protocol (Hustert et al. 
1981).

Photooxidation half-life in water:
46.6d - 5.1yr,
based upon measured rate data for hydroxyl radicals in aqueous
solution (Howard 1991)

Aerobic half-life:
24hr - 168hr,
scientific judgement based upon unacclimated grab sample of
aerobic soil/water suspensions from ground water aquifers
(Howard 1991).

24hr - 120hr,
scientific judgement based upon unacclimated grab sample of
anaerobic marine water/sediment and soil/water suspensions
(Howard 1991).

Methanol is expected to be significantly biodegradable in soil
based on the results of a large number of biological screening
studies, which include soil microcosm studies. 
(Howard
1990).

Standard dilution BOD water, 5-day 48% BODT, sewage inocula
(Dore et al. 1975)

Standard dilution BOD water, 5-day 76% BODT, 20day 97% BODT,
sewage inocula (Price et al. 1974).

Respirometric dilution, 5-day 82.9% BODT, sewage inocula
(Wagner 1976).

Anaerobic-water, 75-80% degradation, sewage inocula (Bekes et
al. 1975).

Biological treatment simulation, 80% degradation, adapted
activated sludge (Swain 1978).

Standard dilution, 5-day 88.7% BODT; seawater dilution, 5-day
70.7% BODT (Takemoto et al. 1981).

Soil-sediment suspensions, aerobic conditions, 5-day CO2
evolution (14-C) of 53.4%; soil-sediment suspensions, anaerobic
conditions, 5-day CO2 evolution (14-C) of 46.3% (Scheunert et 
al. 1987).

The BCF of methanol experimentally measured in fish (golden
ide) was less than 10 (Freitag et al. 1985).

Based on the octanol/water partition coefficient, the BCH value
for methanol can be estimated to be 0.2 from a recommended
regression-derived equation (Lyman et al. 1982).

Toxicity threshold (cell multiplication inhibition test):
bacteria (Pseudomonas putida): 6600 mg/l
(Bringmann & Kühn 1980a)

Removal/secondary treatment:
86%-99%, based upon % degraded under acclimated aerobic
semi-continuous flow conditions (Howard 1991).

Toxicity threshold (cell multiplication inhibition test):
green algae (Scenedesmus quadricauda): 8000 mg/l
protozoa (Entosiphon sulcatum): >10000 mg/l
(Bringmann & Kühn 1980a)