Cyclohex-1,4-ylenedimethanol

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

8.1. Assessment of PBT/vPvB Properties - Comparison with the Criteria of Annex XIII

 

The criteria set out under REACH for determining whether a substance is PBT/vPvB are as follows:

Criterion	PBT criteria	vPvB criteria
P	Half-life (T½) > 60 d in marine water or Half-life (T½) > 40 d in fresh or estuarine water or Half-life (T½) > 180 d in marine sediment or Half-life (T½) > 120 d in fresh or estuarine water; sediment or Half-life (T½) in soil > 120 d	Half-life (T½) > 60 d in marine fresh or estuarine water or Half-life (T½) > 180 d in marine, fresh or estuarine water; sediment Half-life (T½) > 180 d in soil
B	BCF > 2000 L/kg in fresh or marine aquatic species	BCF > 5000 L/kg
T	Chronic NOEC < 0.01 mg/l for marine or freshwater organisms, or Substance is classified as carcinogenic (category 1 or 2), mutagenic (category 1 or 2), or toxic for reproduction (category 1, 2 or 3) or There is other evidence of chronic toxicity, as identified by the classifications: T, R48, or Xn, R48 according to Directive 67/548/EEC.	Not applicable
Note: (a) BCF is bioconcentration factor, NOEC is no-observed effect concentration and CMR is a substance classified as carcinogenic, mutagenic or toxic for reproduction (b) For marine environmental risk assessment, half-life data in freshwater sediment can be overruled by data obtained under marine conditions (c) Substances are classified when they fulfill the criteria for all three inherent properties for P, B and T. However, there is certain flexibility, for instance in cases where one criterion is marginally not fulfilled but the others are exceeded considerably.

 

8.1.1. Persistence Assessment

In a study conducted according to OECD Guideline 301A, CHDM was readily biodegradable with 99.2% of it gone by day 3. A second study was conducted according to OECD Guideline 302B and also showed 98% degradation by study day 19. Therefore, CHDM would not be rated as persistent according to REACH Annex XIII regulation and would not be rated as a P or vP substance (half-life in fresh-water of greater than 60 days).

8.1.2. Bioaccumulation Assessment

A study measuring bioconcentration was not available for CHDM. Log Kow estimates of 0.36 to 1.47 suggest a low potential for bioaccumulation. In addition, the environmental program (EPIWIN v3.0) was run and estimated a log BCF of 0.65 (BCF = 4.45 L/kg wet-wt), and a log BAF of 0.505 (BAF of 3.2 L/kg wet-wt). Both of these values support a low potential to bioaccumulate and are well below the REACH Annex XIII criteria for B or vB.

8.1.3. Toxicity Assessment

All three trophic levels were represented in studies: primary producers represented by algae, plant eating animals represented by daphnids and freshwater snails and predators represented by fish and planarians. A chronic study in fish or daphnids was not available for CHDM. In fathead minnows (Pimphales promelas), the 96-hour LC50 was > 125.3 mg/L and in daphnia, the 96-hour LC50 was > 100 mg/L. The 72-hour algae EC50 was > 122.9 mg/L. CHDM is not classified as mutagenic (category 1 or 2) or toxic for reproduction (category 1, 2 or 3). A chronic toxicity/carcinogenicity study was not identified for CHDM, but a lack of evidence from histopathology in a 90-day study for any organ abnormalities and negative genotoxicity studies suggest that CHDM would not be considered a carcinogen.

There is no evidence to suggest that CHDM would be classified as T/R48 or XN/R48 for chronic toxicity.

CHDM was, however, corrosive to the eye and would be classified as H318. Effects were observed in the eye after direct administration but were cleared in all cases by study day 14.

8.1.4. Summary and overall Conclusions on PBT or vPvB Properties

Overall, CHDM does not meet the criteria for being rated as a PBT or vPvB substance. CHDM appears to be readily biodegradable and does not have the potential to bioaccumulate. Aquatic toxicity is minimal and it is not rated as a mutagen or toxic for reproduction. Studies available do not support CHDM as having adverse chronic toxicity or being a carcinogen. CHDM is considered, however, to be corrosive to the eye and is classified as H318