Acetonitrile

Hydrolysis

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Widely recognized data source. Cited in the EU RAR.

Principles of method if other than guideline:

No information available. Handbook source

GLP compliance:

not specified

Remarks:

Handbook source

Transformation products:

not measured

pH:

7

Temp.:

25 °C

DT50:

> 150 000 yr

Type:

not specified

Remarks on result:

other: hydrolysis rate constant = 5.8 x 10 -3 M-1 hour -1

pH; Rate constant; Half-life(est); Reference

7; 5.8 x 10-3/Mhr; >150,000 yr; Ellington et al. 1988*

9; 5.8 x 10-3/Mhr; 1364 yr; Ellington et al. 1988*

9; 2.1 - 3.5 x 10+6/Msec; >600 yr; Anbar & Neta, 1967*; Dorfman & Adams, 1973*

* cited in Howard, 1993.

The photooxidation half-life for acetonitrile in water, based on rate data for hydroxyl radicals in aqueous solution has also been estimated to be 314 -12559 years (Howard et al. 1991).

It has been stated that hydrolysis is unimportant, to the aquatic fate of acetonitrile, at the pH ranges normal for natural water (Ellington et al. 1988). The half-life for acetonitrile in water has been estimated to be >150,000 years based on a hydrolysis rate constant at pH 7 and 25 deg C of 5.8 x 10 -3 M-1 hour -1 (Howard, 1991).

Executive summary:

Hydrolysis is considered unimportant to the aquatic fate of acetonitrile, at the pH ranges normal for natural water (Ellington et al. 1988). The half-life for acetonitrile in water has been estimated to be >150,000 years based on a hydrolysis rate constant at pH 7 and 25 deg C of 5.8 x 10-3 /Mhr (Howard, 1991). As cited in the EU RAR.

Reference 2

Endpoint:

hydrolysis

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Remarks:

Limited information available. Not widely recognized data sources.

Principles of method if other than guideline:

No information available. Secondary sources.

GLP compliance:

not specified

Remarks on result:

other: Hydrolysis is considered unimportant to the aquatic fate of acetonitrile, at the pH ranges normal for natural water.

Executive summary:

Hydrolysis is considered unimportant to the aquatic fate of acetonitrile, at the pH ranges normal for natural water.

Description of key information

Hydrolysis is not expected to be an important aquatic fate process for acetonitrile.  Acetonitrile is readily biodegradable.

Key value for chemical safety assessment

Half-life for hydrolysis:

150 000 yr

at the temperature of:

25 °C

Additional information

Hydrolysis is considered to be unimportant to the aquatic fate of acetonitrile, at the pH ranges normal for natural water (Ellington et al. 1988). The half-life for acetonitrile in water has been estimated to be >150,000 years based on a hydrolysis rate constant at pH 7 and 25 deg C of 5.8 x 10-3 Mhr (Howard, 1991).