Dodecene

Toxicological Summary

Workers - Hazard via inhalation route

Systemic effects

Acute/short term exposure

DNEL related information

Local effects

Acute/short term exposure

DNEL related information

Workers - Hazard via dermal route

Systemic effects

Acute/short term exposure

DNEL related information

Additional information - workers

There were no acute oral or demal studies available for dodecene. However, other isomerised olefins; alpha, internal, linear and branched – single carbon number, including tetradecene and octadecene, were not acutely toxic when administered via oral or dermal routes in several animal studies. Although no acute inhalation studies were identified for dodecene or any other single carbon number isomerised olefin, acute inhalation studies with structurally similar linear alpha olefins and multiple carbon number isomerised olefin substances (hex-1-ene, hexadec-1-ene, and alkenes, C10/11/12/13) did not report acute adverse effects; hence it can be inferred that dodecene is not acutely toxic via inhalation. Therefore, single carbon number isomerised olefins, including dodecene, do not meet the classification and labelling criteria for acute oral, dermal, or inhalation toxicants according to EU DSD/DPD 67/548/EEC or CLP EU Regulation 1272/2008 (GHS aligned) criteria; therefore short-term DNELs were not derived for these endpoints.

Regulatory classification and labeling for aspiration toxicity relies on the measured or calculated kinematic viscosity of a substance at 40°C rather than results from toxicological studies with animals. There are no viscosity data available for dodecene.  However, read-across viscosity data was available for octadecene, a single carbon number isomerised olefin. The reported kinematic viscosity for octadecene was 3.44 mm²/sec at 40°C (Chilworth Technology LTD, 2010).The discriminating thresholds for classification for aspiration toxicity are 7 mm²/sec and 20.5 mm²/sec for EU DSD/DPD 67/548/EEC and CLP EU Regulation 1272/2008 (GHS aligned), respectively. Based on the read-across strategy used for isomerised olefins, it is inferred that dodecene be classified and labelled as R65: Harmful, may cause lung damage if swallowed, according to EU DSD/DPD 67/548/EEC and Category 1; H304: May be fatal if swallowed and enters airway according to EU CLP Regulation 1272/2008 (GHS aligned). A DNEL is neither feasible nor appropriate for this endpoint.

One developmental/reproductive screening study (Thorsrud, 2003) was available for a single carbon number isomerised olefin, octadecene, which reported no treatment-related adverse effects on fertility or developmental parameters at the highest dose tested (1000 mg/kg bw/day). Results from developmental/reproductive screening studies conducted on other olefin substances such as alkenes, C6 (multiple carbon number isomerised olefin, Thorsrud, 2003), hex-1-ene (linear alpha olefin, Daniel, 1995 (a)), and tetradec-1-ene (linear alpha olefin, Daniel, 1995 (b)) were also negative for effects on fertility and development. The weight of evidence presented by these studies suggests that higher olefin substances, as a group, are unlikely to present a significant hazard potential to fertility and development. However, these studies do not meet standard REACH information requirements for this endpoint since the studies do not fully assess all phases of the reproductive cycle (e.g. oestrus cyclicity, sperm quality, post weaning development, maturation and the reproductive capacity of the offspring). Therefore, these studies cannot be substituted for a full teratogenicity study (OECD 414) or two-generation study (OECD 416). Further testing on a C8 alkene (specific substance has not yet been identified) has been proposed to address these outstanding toxicological endpoint data gaps. In the interim, formal development of worker and general population DNELs for fertility/developmental endpoints will be deferred for all single carbon number isomerised olefins, including dodecene.

A worker-DNEL_{long-term for dermal route-systemic} and worker-DNEL_{long term for inhalation route-systemic} were not derived for single carbon number isomerised olefins, including dodecene, because no adverse findings relevant to human health risk assessment were found in good quality, high reliability repeated oral dose studies with alkenes, C6, alkenes, C16-18, and two studies with alkenes, C20-C24 at limit doses of 1000 mg/kg bw/day (Thorsrud, 1993; Clubb, 2000, Dunster et al., 2008, and Brooker, 1999) and in a read-across 90-day repeated inhalation dose study with linear alpha olefin, hex-1-ene (Bennick et al., 1984).  These results indicate that isomerised olefins with a range of carbon numbers, as a class, possess an inherently low hazard potential with regard to human health. Therefore, derivation of long-term DNELs is unnecessary. A worker-DNEL_{long-term for oral route-systemic}was not calculated for single carbon number isomerised olefins because oral routes of exposure to these substances were not relevant for a worker population.

General Population - Hazard via inhalation route

Systemic effects

Acute/short term exposure

DNEL related information

Local effects

Acute/short term exposure

DNEL related information

General Population - Hazard via dermal route

Systemic effects

Acute/short term exposure

DNEL related information

General Population - Hazard via oral route

Systemic effects

Acute/short term exposure

DNEL related information

Additional information - General Population

General population DNELs for acute effects were not derived because no relevant hazard was apparent from the available toxicological data.

A general population-DNEL_{long-term for oral route-systemic}, general population-DNEL_{long-term for dermal route-systemic}, and general population-DNEL_{long term for inhalation route-systemic}were not derived for single carbon number isomerised olefins, including dodecene,

because no adverse findings relevant to human health risk assessment were found in good quality, high reliability repeated oral dose studies with alkenes, C6, alkenes,C16-18, and two studies with alkenes, C20-C24 at limit doses of 1000 mg/kg bw/day (Thorsrud, 1993; Clubb, 2000, Dunster et al., 2008, and Brooker, 1999) and in a read-across 90-day repeated inhalation dose study with linear alpha olefin, hex-1-ene (Bennick et al., 1984). These results indicate that isomerised olefins with a range of carbon numbers, as a class, possess an inherently low hazard potential with regard to human health. Therefore, derivation of long-term DNELs is unnecessary.