Registration Dossier
Registration Dossier
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EC number: 203-636-9 | CAS number: 108-99-6
Toxicological Summary
Administrative data
Workers - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 2.5 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 225
- Modified dose descriptor starting point:
- NOAEC
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 7.5 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 0.33
Local effects
Long term exposure
- Hazard assessment conclusion:
- no-threshold effect and/or no dose-response information available
Acute/short term exposure
- Hazard assessment conclusion:
- no-threshold effect and/or no dose-response information available
DNEL related information
Workers - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.14 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 50
- Modified dose descriptor starting point:
- NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.42 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 0.33
Local effects
Long term exposure
- Hazard assessment conclusion:
- no-threshold effect and/or no dose-response information available
Acute/short term exposure
- Hazard assessment conclusion:
- no-threshold effect and/or no dose-response information available
Workers - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- high hazard (no threshold derived)
Additional information - workers
The chronic oral/dermal systemic DNEL is 0.14 mg/kg bw/d, based on a NOAEL of 7 mg/kg bw/d from the 2-year NTP chronic bioassay of pyridine in F344 rats, and an AF of 50. It is legitimate to read-across from pyridine, as pyridine is a category member along with 2-methylpyridine, 3-methylpyridine and 4-methylpyridine. The basis of this category is provided in a chemical category report format attached to this IUCLID5 file, and this category is an established category accepted by the U.S. Environmental Protection Agency.
A sub-acute inhalation study of beta-picoline (3-methylpyridine), of 14 days duration in rats (Chen and Krauss, 1984) was selected for deriving the DNEC. The NOAEC was 290 ppm, equivalent to 1105 mg/m3. To the NOAEC are applied two dose modifiers of 0.75 and 0.67 to produce a modified dose descriptor of 555 mg/m3. Assessment factors total 225 (2.5 for interspecies (no allometric scaling factor is indicated (Table 8.4, ECHA TGD R.8, 2008)), 5 for intraspecies, 6 for duration, 1 for complete dataset, and 3 for a Dose-Response AF due to a less robust study design and pathology assessment in the 14 day study, compared to a 28-day study.) The chronic systemic DNEC is 2.5 mg/m3. This applies to all members of thePyridine and Pyridine Derivatives Category, an established category accepted by the U.S. Environmental Protection Agency. Category members include pyridine, 2-methylpyridine, 3-methylpyridine and 4-methylpyridine.
In support of this DNEC are the results of an additional inhalation study of pyridine toxicity (Watanabe, et.al, 1979), part of the U.S.Voluntary HPV submission package on the Pyridine and Pyridine Derivatives Category, but to which legal access was not able to be obtained. A robust summary of the study is provided as an attachment in IUCLID5, and indicates that the NOAEC in CD rats after a 6-month inhalation study (6 hr/day, 5 days/week) is >100 ppm or 323 mg/m3. This results in a DNEC of 6.5 mg/m3, and suggests that the use of the Chen and Krauss study, with the selected AFs, provides values which are sufficiently conservative and valid for determining acceptable levels of exposure.
As pyridine is an irritant to the skin and eye, local effects will be evaluated in a qualitative manner. Risk management measures, such as gloves and goggles/safety glasses, are recommended to minimize the risk of adverse effects of local exposures to pyridine.
General Population - Hazard via inhalation route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 1.9 mg/m³
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 50
- Modified dose descriptor starting point:
- NOAEC
Acute/short term exposure
- Hazard assessment conclusion:
- exposure based waiving
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- exposure based waiving
Acute/short term exposure
- Hazard assessment conclusion:
- exposure based waiving
DNEL related information
General Population - Hazard via dermal route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.07 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 100
- Modified dose descriptor starting point:
- NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- exposure based waiving
DNEL related information
Local effects
Long term exposure
- Hazard assessment conclusion:
- exposure based waiving
Acute/short term exposure
- Hazard assessment conclusion:
- exposure based waiving
General Population - Hazard via oral route
Systemic effects
Long term exposure
- Hazard assessment conclusion:
- DNEL (Derived No Effect Level)
- Value:
- 0.07 mg/kg bw/day
- Most sensitive endpoint:
- repeated dose toxicity
DNEL related information
- Overall assessment factor (AF):
- 100
- Modified dose descriptor starting point:
- NOAEL
Acute/short term exposure
- Hazard assessment conclusion:
- exposure based waiving
DNEL related information
General Population - Hazard for the eyes
Local effects
- Hazard assessment conclusion:
- high hazard (no threshold derived)
Additional information - General Population
Most of these endpoints are addressed qualitatively, according to exposure-based waiving. There are no applications of picolines involving the general population, to the knowledge of the manufacturer/importer. Several DNELs have been generated in order to assess risk of man via the environment. While the general population as consumers may come in contact with pyridine as a component of cigarette smoke, food components or constituents of flavours/food additives, or pharmaceuticals, these exposures do not derive from industrial sources of pyridine. They are outside the scope of REACH and are considered under the jurisdiction of other regulations.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
