Decanoic acid, mixed esters with heptanoic acid, octanoic acid and pentaerythritol

PBT assessment

PBT assessment: overall result

Reference

Name:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and pentaerythritol

Type of composition:

legal entity composition of the substance

State / form:

liquid

Reference substance:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and pentaerythritol

Reference substance:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and pentaerythritol

Reference substance:

Decanoic acid, mixed esters with heptanoic acid, octanoic acid and pentaerythritol

PBT status:

the substance is not PBT / vPvB

Justification:

Assessment of PBT/vPvB Properties has been conducted in accordance with the guidance given in Annex XIII of Regulation 1907/2006 (as amended by Commission Regulation No 253-2011 of 15 March 2011). A summary of these findings is as presented below:

 

Persistence

A key study is available on ready biodegradability of the substance which was conducted in accordance with OECD testguidline 301B and EU-Method C.4-C.The result of the study showed that the overall degradation in 28 days was 84% (CO2 evolution), and thus was concluded that the substance is Readily biodegradable and as such does not meet the criterion for Persistant/very Persistant.

 

Bioaccumulation

A key study is available, assessing the substances octanol-water partition coefficient in accordance with OECD guideline 117 and EU-method A.24. The study concluded that the test item contains (77.25% of the total peak areas) which have a log Kow outside of the range of the reference item and as such was determined to be > 6.5. Based on this information the substance screens as potentially Bioaccumulative/very Bioaccumulative.

However due to the substances variable molecular weight (528.725-905.6842) and as a hydrophobic UVCB given its low solubility in water (< 0.14 mg/L), that the linear relationship between bioaccumulation and log kow > 6 the log BCF does not increase linearly with log Kow and as such cannot be concluded as bioaccumulative on the basis of the octanol-water partition coefficient alone.  An investigation utilising the US EPA BCFBAF v3.01 QSAR tool confirms that the substance is not considered to be bioaccumulative, on the basis of the following results:

Mono: Estimated Log BCF = 0.500 (BCF = 3.162 L/kg wet-wt)

Di: Estimated Log BCF = 0.338 (BCF = 2.178 L/kg wet-wt)

Tri: Estimated Log BCF = 0.338 (BCF = 2.178 L/kg wet-wt)

An acute oral toxicity study in accordance with OECD test guideline 423 using the test substance and a 28-day toxicity study (oral) has been conducted on decanoic acid, mixed esters with octanoic acid, pentaerythritol and valeric acid (structurally analogous substance) which was conducted in accordance with OECD test guideline 407. The conclusion from these studies was that there were a distinct lack of toxicologically relevant effects associated with the test substances when administered orally to male and female rats. The lack of effects are a key indicator that for this type of substance, that the bioavailability is considered to be low via the oral route for animals. The absorption of highly lipophilic substances (log Kow ≥ 4) may be limited by the inability of such substances to dissolve in gastrointestinal fluids and therefore make contact with the mucosal surface. However, the absorption of such substances will be increased if they undergo micellular solubilisation by bile salts.

Based on the above information, the substance is proposed to not be Bioaccumulative/very Bioccumulative based on its physicochemical properties, QSAR results and with the lack of effects noted in the available oral toxicity studies.

 

Toxicity

A number of valid key studies are available which have determined the substance to be not classified as systemically toxic, carcinogenic, mutagenic, toxic to reproduction or toxic to aquatic organisms above the limits of solubility. The results of the fresh water organisms for the test substance were concluded as follows: NOEC 48h-NOEC ≥ 100 mg/L (Daphnia magna) and 72h NOEC ≥ 100 mg/L (Desmodesmus subspicatus). Therefore based on this information the substance does not meet the criterion for Toxic according to REACH Annex XIII.

 

Overall conclusion

Based on the assessment described in the subsections above the substance is not a PBT / vPvB substance.

Although the substance potentially screens as Bioacumulative/very Bioacumulative based on its octanol/water partition coefficient, the lack of effects evident from the oral toxicity studies and calculated BCF using QSAR implies the lack of bioavailability and as such its bioaccumulation potential. Additionally the substance does not fulfil the criteria for Persistency and Toxic as specified in REACH Annex XIII. 

Therefore the substance cannot be considered as a PBT or vPvB substance, based on the available data.