Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Stability

Hydrolysis as a function of pH

Data waiving in accordance with column 2 of REACH Annex VIII.

 

Biodegradation

Biodegradation in water

The submission substance is readily biodegradable as demonstrated in OECD TG 301 B.

 

Biodegradation in surface water, sediment and soil: simulation test

Data waiving in accordance with column 2 of REACH Annexes IX and X.

 

Identification of degradation products

Data waiving in accordance with column 2 of REACH Annexes IX and X.

Bioaccumulation

Bioaccumulation: aquatic

Data waiving in accordance with column 2 of REACH Annexes IX and X.

Transport and distribution

Adsorption / desorption

Data waiving in accordance with column 2 of REACH Annexes VIII, IX and X.

Additional information

Stability

In air, the photodegradation of 1,3 -butanediol by OH-radicals was estimated to be 14.2329 E-12 cm³/molecule*sec, leading to a half-life of approx. 27 hours (1.1 days) (ECT, 2008).

First order rate constants for photochemical oxidation in water by OH radicals were reported to be 2.2E09 L/mol*sec at pH 7 (Buxton et al., 1988; RL4). No data on phototransformation in soil are available.

Biodegradation in water

The ready biodegradability of 1,3 -butanediol was studied in a Modfied Sturm Test following OECD 301B. The test substance was degraded to 81% (CO2/ThCO2) after 29 days. The 10 -days window was met. The validity criteria were fulfilled. 1,3 -Butanediol is readily biodegradable according to OECD criteria (Barnes, 2000).

Bioaccumulation aquatic/sediment:

Based on a calculated log Pow of -0.29, the BCF was estimated to be 3.2 (log BCF = 0.5) (ECT, 2008). The potential for bioaccumulation in aquatic and benthic organisms is therefore expected to be very low.

Transport and distribution

Adsorption / desorption

Based on a calculated Koc of 1 (PCKoc v1.66), 1,3 -butanediol is expected to have high mobility in soil (ECT, 2008).

Henry's Law constant / Other distribution data

The Henry's Law constant (HLC) was estimated to be 0.0233 Pa*m³/mol at 25 °C. Taking this value, volatilization half-lives of 101 and 1102 days were estimated by EPIWIN v3.20 for a model river and a model lake, respectively (ECT, 2008)