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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Hydrolysis:

Hydrolysis of an organic molecule occurs when a molecule (R-X) reacts with water (H2O) to form a new carbon-oxygen bond after the carbon-X bond is cleaved. Mechanistically, this reaction is referred to as a nucleophilic substitution reaction, where X is the leaving group being replaced by the incoming nucleophilic oxygen from the water molecule.

Chemicals that are susceptible to hydrolysis contain functional groups that can be displaced by a nucleophilic substitution reaction.
 Substances that have the potential to hydrolyze include alkyl halides, amides, carbamates, carboxylic acid esters and lactones, epoxides, phosphate esters, and sulfonic acid esters. The lack of a leaving group renders a compound resistant to hydrolysis.

Aliphatic alcohols are resistant to hydrolysis because they lack a functional group that is hydrolytically reactive.
Therefore, this fate process will not contribute to a measurable degradative loss of this substance from the environment.

Phototransformation in air:

Alcohols, C7 -9 -iso, C8 -rich has the potential to degrade in the atmosphere from hydroxyl radical attack and photodegradation can be a predominant daylight atmospheric degradation process for this substance. The photodegradation half-life of this substance as mediated by OH-attack is estimated as 0.85days or 10.2 hours based on a 12-hour sunlight day. The half-life is calculated for a 12 -hr day because it normalizes degradation to standard day-light period during which hydroxyl radicals needed for degradation are generated.

Phototransformation in water and soil:

A conservative approach to estimating a photochemical degradation rate is to assume that degradation will occur in proportion to the amount of light with wavelengths >290 nm absorbed by the molecule. Alkyl alcohols contain molecules that are oxygenated aliphatic compounds, which absorb UV light below 220 nm, a range of UV light that does not reach the earth's surface. Therefore, aliphatic alcohols will not undergo direct photolysis and this fate process will not contribute to a measurable degradative loss of this substance from the environment.

Biodegradation:

Alcohols, C7 -9 -iso, C8 -rich, is readily biodegradable and has been shown to biodegrade to a significant extent in a test of ready biodegradability (82% in 28 days) using standard OECD test guidelines.  Therefore, biotic degradation will significantly contribute to the loss of this substance from the environment.

Bioaccumulation:

Experimental data along with the biochemical evidence suggest that this substance has a very low potential for bioconcentration in aquatic species and is not expected to bioaccumulate.

Adsorption / desorption:

The soil adsorption coefficient was estimated for Alcohols, C7-9-iso, C8-rich using a log Kow method and the measured log Kow. The Koc = 149 (log Koc = 2.17).

Distribution modelling:

Alcohols, C7-9 -iso, C8 -rich, will partition largely to the water compartment, followed by the sediment and minimally to the air and soil compartments, based on all available measured data.

Henry's Law Constant:

Henry's Law constant for Alcohols, C7-9-iso, C8-rich, 6.5 Pa.m3/mole at 20 degrees C, indicates that volatilization from water is expected to occur at a significant rate.