3,3'-dimethylbiphenyl-4,4'-diyl diisocyanate

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water and sediment: simulation testing, other

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 302 C (Inherently Biodegradability)

Key result

Remarks on result:

other: No %Degr. indicated. Based on the short half-life in water, the substance is essentially unavailable for biodegradation.

Methylenediphenyl diisocyanate (MDI) is inherently reactive in water, with a predicted half-life in solution of a minute or less. Because of this high reactivity, MDI can have only a transient existence in water, and as such, is essentially unavailable for uptake and bioaccumulation or for biodegradation.

Conclusions:

By applying published data of a supporting substance the degradation in surface water is not relevant for TODI. TODI has - based on the analoge behavoiour of MDI - only a transient existence in water, and as such, is essentially unavailable for uptake and bioaccumulation or for biodegradation.

Executive summary:

TODI is highly insoluble in water. Once in contact with water, TODI hydrolyses quite fast. Resulting degradation products are considered to be inert and insoluble. Thus neither TODI nor its degradation products are available for uptake or bioaccumulation or for biodegradation.

Reference 2

Endpoint:

biodegradation in water: sediment simulation testing

Data waiving:

study technically not feasible

Justification for data waiving:

the study does not need to be conducted because the substance is highly insoluble in water

Description of key information

The study does not need to be conducted because TODI is highly insoluble in water. Additionally, once in contact with water, TODI hydrolyses quite fast. Resulting degradation products are considered to be inert and insoluble in water. Thus neither TODI nor its degradation products are available for uptake or bioaccumulation or for biodegradation.