23/03/2010

CYCLODODECANE

1  Chemical identity

Common name / Cyclododecane
Chemical name (IUPAC) / Cyclododecane
Synonym(s)
Chemical class (when available/relevant)
CAS number / 294-62-2
EU number / 206-033-9
Molecular formula / C12H24
Molecular structure /
Molecular weight (g.mol-1) / 168.33

2  Existing evaluations and Regulatory information

Annex III EQS Dir. (2008/105/EC) / Not Included
Existing Substances Reg. (793/93/EC) / Not applicable
Pesticides(91/414/EEC) / Not included in Annex I
Biocides (98/8/EC) / Not included in Annex I
PBT substances / Fulfilling PBT criteria*
Substances of Very High Concern (1907/2006/EC) / No*
POPs (Stockholm convention) / No
Other relevant chemical regulation (veterinary products, medicament, ...) / No
Endocrine disrupter / Not investigated

*Cyclododecane was considered a PBT/vPvB substance on the basis of screening criteria by the TC NES subgroup [1]. However, in the SVHC support document [3] it is concluded that ” it is currently not possible to justify the identification of Cyclododecane as a substance of very high concern under Article 57 of REACH Regulation.” The B and vB criteria under Annex XIII are met, but only screening data are available for T and P.

3  Proposed Quality Standards (QS)

3.1  Environmental Quality Standard (EQS)

QS for -- is the “critical QS” for derivation of an Environmental Quality Standard

Add any comment on possible residual uncertainty.

Value / Comments
Proposed AA-EQS for [matrix] [unit]
Corresponding AA-EQS in [water] [µg.L-1] / Critical QS is QS--.
See section 7
Proposed MAC-EQS for [freshwater] [µg.L-1]
Proposed MAC-EQS for [marine waters] [µg.L-1] / See section 7.1

3.2  Specific Quality Standard (QS)

Protection objective[1] / Unit / Value / Comments
Pelagic community (freshwater) / [µg.l-1] / See section 7.1
Pelagic community (marine waters) / [µg.l-1]
Benthic community (freshwater) / [µg.kg-1 dw] / e.g. EqP,
see section 7.1
[µg.l-1]
Benthic community (marine) / [µg.kg-1 dw]
[µg.l-1] / -
Predators (secondary poisoning) / [µg.kg-1biota ww] / See section 7.2
[µg.l-1] / (freshwaters)
(marine waters)
Human health via consumption of fishery products / [µg.kg-1biota ww] / See section 7.3
[µg.l-1] / (freshwaters)
(marine waters)
Human health via consumption of water / [µg.l-1]

4  Major uses and Environmental Emissions

4.1  Uses and Quantities

Cyclododecane is a high production volume (HPV) chemical. Four producers/importers are listed in ESIS [7]. According to [1] two producers operate in the EU at present. Cyclododecane is used almost exclusively as an intermediate in synthesis by the chemical industry [1 & 6].

4.2 Estimated Environmental Emissions

Cyclododecane is produced in a closed system and used as an intermediate in a predominantly closed system according to one producer [6]. Due to strict controls, no release to the atmosphere or hydrosphere from production is expected. From consumption of the total produced quantity as an intermediate by all customers, zero direct emissions to the atmosphere have been declared and emissions of 118 kg/year to the recipient surface water bodies have been estimated by SimpleTreat [2] and [6]. This estimate is based on emissions of 1680 kg/year to untreated waste water. The model indicated a 93% removal (ca. 92 % adsorbed to sludge, ca. 1 % to air) during waste water treatment. The sludge is incinerated.

5  Environmental Behaviour

5.1  Environmental distribution

Master reference
Water solubility (mg.l-1) / < 1
10
0.11 / [9]
[12]
WSKOW v1.41
Volatilisation
Vapour pressure (Pa) / 7 at 20°C / [8]
Henry's Law constant (Pa.m3.mol-1) / > 100 / [1]
Adsorption / The value 6500 is used for derivation of quality standards.
Organic carbon – water partition coefficient (KOC) / KOC = 6500 (estimated) / [3]
Suspended matter – water partition coefficient(Ksusp-water) / 163.4 / Calculated from the Koc according to the methodology described in [4]
Bioaccumulation / The BCF value 13700 on fish is used for derivation of quality standards.
Octanol-water partition coefficient (Log Kow) / 6.12 (calculated with Kowwin v 1.66)
6.71 (calculated with CLOGP3)
>6.19 (measured, study reliability: considered not assignable) / [13]
CLOGP3
[1] & [2]
log Kow = 7.6 (25 °C, OECD 117; HPLC method) / [6]
BCF (measured) / 13700 (mean BCF of 6-10 week samples, measured BCFs in the range 3690-18700) / [9]

5.2  Abiotic and Biotic degradations

Master reference
Hydrolysis / DT50= -no data available- d at °C (distilled water)
DT50= -no data available- d at °C (salt water)
Cyclododecane is not expected to hydrolyze in the environment. / [3]
Photolysis / DT50= 23 h (estimated atmospheric half-life) / [3]
Biodegradation / DT50 (type of water)= -no data available- d
0-12 % degraded after 14 days ready biodegradability test.
3% degradation in 28 days (OECD 301D).
No degradation in 28 days (Modified Sturm test, C.5. of 84/448/EEC).
30% degradation after 8 days at 30˚C by mixed bacterial sediment population. 2/5 isolated bacterial strains grew using cyclododecane as the sole carbon source.
Cyclododecane is oxidized by by Rhodococcus ruber CD4. A sequence of degradation steps has been identified.
18 % degradation in 28 days (BODIS Test) / [9]
[14]
[15]
[10]
[11]
[14]

6  Aquatic environmental concentrations

6.1  Estimated concentrations

No data available.

Compartment / Predicted environmental concentration (PEC) / Master reference
Freshwater
Marine waters (coastal and/or transitional)
Sediment
Biota (freshwater)
Biota (marine)
Biota (marine predators)

6.2  Measured concentrations

Compartment / Measured environmental concentration (MEC) / Master reference
Freshwater / No data available
Marine waters (coastal and/or transitional) / No data available
WWTP effluent / Identified but not quantified / [22]
Sediment / Identified in an extract from a sediment sample from Tobin Lake, Canada / [16]
Biota / 3.9 µg/kg ww raw beef (tentative identification) / [20]
11.8 mg/kg ww fat overheated beef fat (crude estimate) / [21]
Identified in extracts of Iberian ham, approx. 0.0133 % = 133 mg/kg / [23]
Tentatively identified in fumes from cooking meat (beef) / [24]
One of the major tentatively identified volatile components in extracts of toasted sesame seeds and in extracts of canola seeds. / [25]
Essential oil of Chamaemelum nobile (Roman camomile) harvested at three different sites. Mean concentrations: 1.91, 2.01 and 2.55 % = 19,100, 20,100, and 25,500 mg/kg oil. / [17]
Identified in essential oils of populations of Hypericum perforatum.
Calculated concentrations in plant material: 17-1229 mg/kg dw = 17,000 – 1,229,000 µg/kg dw / [19]
1.4 % = 14,000 mg/kg oil of Amomum ptycholimatum. / [18]
Biota (marine predators) / No data available

The cited reports on the identification and quantification of the substance in the environment indicate production of cyclododecane in plants; cyclododecane has been found in seeds and essential oils, and also in meat from animals feeding on plants.

7  Effects and Quality Standards

7.1  Acute and chronic aquatic ecotoxicity

ACUTE EFFECTS / Master reference
Algae & aquatic plants
(mg.l-1) / Freshwater / Scenedesmus subspicatus / 72 h
EC50: > 2.1 (biomass)
No effect seen at highest tested concentration (study reliability: not valid according to [1] and [3], valid without restrictions according to [2]).
Reasons for “not valid” in [1] and [3] are not scientifically justified according to [6]. / [26], cited in
[1] and [2]
Marine / Algae / 72 h
LC50: 0.019 (Ecosar v0.99h predicition) / [2] and [3]
Invertebrates
(mg.l-1) / Freshwater / Daphnia pulex / 48 h
EC50: 21 (study reliability: not valid according to [1], valid with restrictions according to [2], not valid according to [6] ) / [27], cited in
[1] and [2]
Daphnia magna / 24 h
EC50: > 2.6 (study reliability: not assignable according to [2], not evaluated by [1] since report not available) / [28], cited in
[1] and [2]
Daphnia / 48 h
LC50: 0.024 (Ecosar v0.99h predicition) / [2] and [3]
Marine / Gender species / d or h
EC50: No data available
Sediment / Gender species / d or h
EC50: No data available
Fish
(mg.l-1) / Freshwater / Cyprinus carpio / 96 h
LC50: > 1 (no mortality observed) (study reliability: valid without restriction according to [2], not evaluated by [1] since report not available) / [29], cited in
[1] and [2]
Oryzias latipes / 48 h
LC50: 21.8 (no mortality observed) (study reliability: invalid according to [1] and [2]). / [9], cited in
[1] and [2]
Fish / 96 h
LC50: 0.017 (Ecosar v0.99h predicition) / [2] and [3]
Marine / Gender species / d or h
EC50: No data available
Sediment / Gender species / d or h
EC50: No data available
Other taxonomic groups / Gender species / d or h
EC50: No data available
CHRONIC EFFECTS / Master reference
Algae & aquatic plants
(mg.l-1) / Freshwater / Scenedesmus subspicatus / 72 h
NOEC: ≥ 2.1 (biomass)
No effect seen at highest tested concentration (study reliability: not valid according to [1] and [3], valid without restrictions according to [2] )
Reasons for “not valid” in [1] and [3] are not scientifically justified according to [6]. / [26], cited in
[1] and [2]
Marine / Gender species / d
NOEC: No data available
Invertebrates
(mg.l-1) / Freshwater / Gender species / d
NOEC: No data available
Marine / Gender species / d
NOEC: No data available
Sediment / Gender species / d
NOEC: No data available
Fish
(mg.l-1) / Freshwater / Gender species / d
NOEC: No data available
Marine / Gender species / d
NOEC: No data available
Sediment / Gender species / d
NOEC: No data available
Other taxonomic groups / Gender species / d
NOEC: No data available

The ecotoxicological data for cyclododecane found in the PBT Summary fact Sheet from 2007 [1], the IUCLID Data Set last updated 2006 [2], and the SVHC Support Document from 2008 [3], has not been evaluated due to the lack of available reports, or been considered not valid according to [1] and [3]. The results of the ecotoxicological data indicate however no toxicity at concentrations below water solubility. This is in contrast to the Ecosar v0.99h predictions. No other ecotoxicological data have been found during searches in the US EPA ECOTOX database, TOXLINE or in open scientific literature (last search 2010-03-04).

Due to the limited amount of valid ecotoxicological data, and to the fact that no effects have been seen at concentrations below solubility, it is not possible to calculate tentative QSwater or QSsediment.

Tentative QSwater / Relevant study for derivation of QS / Assessment factor / Tentative QS
MACfreshwater, eco / Gender species / d or h
EC50: mg.l-1 / µg.l-1
MACmarine water, eco / µg.l-1
AA-QSfreshwater, eco / Gender species / 21d
NOEC: mg.l-1 / µg.l-1
AA-QSmarine water, eco / µg.l-1
AA-QSfreshwater, sed. / - / EqP / - µg.kg-1ww
- µg.kg-1dw
AA-QSmarine water, sed. / - / EqP / - µg.kg-1ww
- µg.kg-1dw

7.2  Secondary poisoning

Secondary poisoning of top predators / Master reference
Mammalian oral toxicity / Rat / Oral / 29 days / increase in liver and kidney weights, histological effects
NOAEL : 150 mg.kg-1bw.d-1
NOEC : 1500 mg.kg-1biota ww (CF=10)
Study considered valid without restrictions according to [2] / [30]
Rat / Oral / 15 days / Endpoint
NOAEL : 250 mg.kg-1bw.d-1
NOEC : 2500 mg.kg-1biota ww (CF=10)
Study considered valid with restrictions according to [2] / [31]
Avian oral toxicity / No data available

The tentative QSbiota is derived from the NOEC 1500 mg.kg-1biota ww of the 29 days rat study employing an assessment factor of 300 according to Table 4-3 in the TGD for deriving EQS [5].

The corresponding tentative QS for freshwater and marine waters are calculated with the following formulas:

QSfreshwater (µg/l) = QSbiota (µg/kg) / (BCF (l/kg) * BMF1)

QSwater (µg/l) = QSbiota (µg/kg) / (BCF (l/kg) * BMF1 * BMF2)

For the calculation, the BCF 13700 (see Chapter 5.1), and the default BMFs, for substances with BCF 5000, BMF1: 10 and BMF2: 10, given in Table 4-6 in the TGD for deriving EQS [5] are used.

Tentative QSbiota / Relevant study for derivation of QS / Assessment
factor / Tentative QS
Biota / NOEC : 1500 mg.kg-1biota ww / 300 / 5000 µg.kg-1biota ww
corresponding to
0.036 µg.L-1 (freshwater)
0.0036 µg.L-1 (marine waters)

7.3  human health

Human health via consumption of fishery products / Master reference
Mammalian oral toxicity / Rat / Oral / 29 days / increase in liver and kidney weights, histological effects
NOAEL : 150 mg.kg-1bw.d-1
NOEC : 1500 mg.kg-1biota ww (CF=10)
Study considered valid without restrictions according to [2] / [30]
CMR / Negative in Ames test and a chromosomal aberration test. No in vivo genetic toxicity data or data on carcinogenicity, toxicity to fertility, teratogenicity or toxicity to reproduction available. / [2]

The NOAEL 150 mg.kg-1bw.d-1 from the 29 days rat study is used to calculate the QSbiota,hh using the formula given below according to the TGD for deriving EQS [5]. The threshold level (TL) is calculated from the NOAEL divided by an assessment factor of 300 (same as for secondary poisoning). It is not clear from the EQS-TGD which AF to use!


The corresponding tentative QSwater is calculated according to the following formula:

QSwater (µg/l) = QSbiota,hh (µg/kg) / (BCF (l/kg) * BMF1)= 30000/13700*10 = 0.22 µg/l

Tentative QSbiota, hh / Relevant study for derivation
of QSbiota, hh / Assessment
Factor / Tentative QSbiota, hh
Human health / NOAEL 150 mg.kg-1biota ww / 300 ? / 30000 µg.kg-1biota ww
(0.22 µg.L-1)

Since no EU or WHO drinking water standard is available, a provisional drinking water standard is calculated in accordance with section 3.9.2 of the EQS-TGD [5]. Since no ADI or TDI is available, TLhh is estimated from the mammalian NOAEL value 150 mg.kg-1bw.d-1 divided by 100? according to equation C in section 3.9.2 of the EQS-TGD.

5.3 mg/l

Human health via consumption of drinking water / Master reference
Existing drinking water standard(s) / µg.L-1 (preferred regulatory standard) / Directive 98/83/EC
Any guideline / 5300 µg.L-1
(provisional drinking water standard) / calculated according to the EQS-TGD [5]

8  Bibliography, Sources and supportive information