Substance Identity
CAS Number 129-20-4
Chemical Name 3,5-Pyrazolidinedione, 4-butyl-1-(4-hydroxyphenyl)-2-phenyl-
Type of substance Organic
SMILES CCCCC1C(=O)N(N(C1=O)c2ccc(O)cc2)c3ccccc3
Moiety of concern organic
Categorization Results

Meets Government of Canada Categorization Criteria? No
Meets Human Health Categorization Criteria? No
Meets Environmental Criteria for Categorization? No
Persistent (P)? No
Rational for P QSAR
Bioaccumulative (B)? No
Rational for B QSAR
Inherently Toxic to Aquatic Organisms (iT)? Yes
Rational for iT QSAR
DSL Quantity range (tonnes/year) Unknown Quantity

Ecological data supporting decisions

Underlying data regarding persistence

Media of concern leading to Categorization Water
Experimental Biodegradation half-life (days) Not Available
Predicted Ultimate degradation half-life (days) 15
MITI probability of biodegradation 0.0165
TOPKAT probability of biodegradation 0
EPI Predicted Ozone reaction half-life (days) 999
EPI Predicted Atmospheric Oxidation half-life (days) 0.281

Underlying data regarding Bioaccumulation

Empirical Log Kow 2.72
Log Kow predicted by KowWin 3.04
Log BAF T2MTL predicted by Gobas 1.53656290942152
Log BCF 5% T2LTL predicted by Gobas 1.44252886896904
Log BCF Max predicted by OASIS 2.43536397266912
Log BCF predicted by BCFWIN 1.394

Underlying data regarding inherent toxicity to aquatic organisms

Pivotal value for iT (mg/l) 0.2293
Toxicity to fathead minnow (LC50 in mg/l) as predicted by Topkat v6.1 0.2293
Toxicity to fish (LC50 in mg/l) as predicted by Ecosar v0.99g 0.446
Toxicity to fish (LC50 in mg/l) as predicted by Oasis Forecast M v1.10 201.8224
Toxicity to fish (LC50 in mg/l) as predicted by Aster 39.568867
Toxicity to fish (LC50 in mg/l) as predicted by PNN 732.68615
Toxicity to fish, daphnia, algae or mysid shrimp (EC50 or LC50 in mg/l) as predicted by Ecosar v0.99g 19.349
Toxicity to fish (LC50 in mg/l) as predicted by Neutral Organics QSAR in Ecosar v0.99g 2.53E-001

Human Health data supporting decisions
Underlying data regarding potential for exposure

LPE/IPE/GPE Lowest Potential for Exposure (HC Simple Exposure Tool)

Underlying data regarding Previous Assessments

Underlying data regarding Simple Hazard Assessment


Underlying data regarding Complex Hazard Assessment