Provisional Peer-Reviewed Toxicity Values (PPRTVs)

1-Methylnaphthalene

CASRN 90-12-0

PPRTV Toxicity Values Summary Table

Noncancer Assessment

Estimate of Chronic Reference Dose for Oral Exposure (RfD)Last Updated: 03/29/2024
System RfD (mg/kg-day) Basis PoD UF Confidence
Respiratory 1 x 10-2 PAP LOAEL(HED) : 10.7 mg/kg-day 1000 NA: Screening Value
Species Studied: Mouse/M
Principal Study: Murata et al. (1993)



Estimate of Subchronic Reference Dose for Oral Exposure (RfD)Last Updated: 03/29/2024
System RfD (mg/kg-day) Basis PoD UF Confidence
Hepatic 2 x 10-1 Increased relative liver weight BMDL0.1RD(HED) : 24.12 mg/kg-day 100 NA: Screening Value
Species Studied: Rat/M
Principal Study: METI (2009b)



Estimate of Chronic Reference Concentration for Inhalation Exposure (RfC)Last Updated: 03/29/2024
System RfC (mg/m3) Basis PoD UF Confidence
Respiratory 3 x 10-6 Mucous cell hyperplasia in nasopharyngeal tissues BMCL10(HEC) : 0.009 mg/m3 3000 Low
Species Studied: Rat/M
Principal Study: Kim et al. (2020)



Estimate of Subchronic Reference Concentration for Inhalation Exposure (RfC)Last Updated: 03/29/2024
System RfC (mg/m3) Basis PoD UF Confidence
Respiratory 3 x 10-5 Mucous cell hyperplasia in nasopharyngeal tissues BMCL10(HEC) : 0.009 mg/m3 300 Low
Species Studied: Rat/M
Principal Study: Kim et al. (2020)


Cancer Assessment

Weight of Evidence for CancerLast Updated: 03/29/2024
- Oral: Suggestive Evidence of Carcinogenic Potential
Inhalation: Inadequate Information to Assess Carcinogenic Potential


Estimate of Carcinogenic Risk from Oral ExposureLast Updated: 03/29/2024
Oral Slope Factor: 5.1 x 10-2 per mg/kg-day
Tumor site(s): Respiratory
Cancer: Combined lung adenoma or adenocarcinoma
Species Studied: Mouse/M
Duration: 81 weeks
Principal Study: Murata, et al. (1993)
Note: An adjustment was applied to accout for the less-than-lifetime observation period


Estimate of Carcinogenic Risk from Inhalation ExposureLast Updated: 03/29/2024
Not determined

Provisional Peer-Reviewed Toxicity Values (PPRTVs)