Registration Dossier

Classification & Labelling & PBT assessment

PBT assessment

Administrative data

PBT assessment: overall result

PBT status:
the substance is not PBT / vPvB

Classification of Clioquinol for effects in the environment

Several major guideline – estimation values (Klimisch 2) are available forClioquinol, indicates no toxic effect on fish and any other tropic levels.  Thus, the value which have been considered for further calculation (fish) is LC50 = 10 mg/L.


In determining the classification appropriate toClioquinol, it is necessary to consider all available evidence concerning its persistence, potential to accumulate and predicted or observed environmental fate and behavior that may present a long-term and/or delayed danger to the structure and/or functioning of aquatic ecosystems. These points are considered below.



Reliable studies are available to demonstrate thatClioquinolis non persistent in nature and so is considered to have rapid biodegradation in the environment. In other wordsClioquinol degradation may therefore be expected to be fast. Thus it can be inferred thatClioquinolis non persistent in character. 


Clioquinol is non persistent and so do not satisfy the criteria for classification as persistent (P). 


Potential to accumulate

Measured log Kow values forClioquinolis less than 4 (log Kow = 3.8). The potential forClioquinolto bioaccumulate in the tissues of organisms that inhabit aquatic or terrestrial matrices is negligible as the BCF factor for the substance is less than 1000.  


 The calculated BCF ofClioquinolis 91 dimensionless and below the threshold of 2000. 


Clioquinoldoesnot satisfy the criterion for classification as bioaccumulative (B).


The toxicity values of fish, invertebrates and algae are LC50 = 10 mg/L, NOEC = 8.449671 mg/L and NOEC = 4.034495 mg/L, respectively. The end point result values of fish indicate that the substance will have toxicity effect within the classifying range. So, the substance will qualify for classification as per the CLP regulation. But asthe BCF value of clioquinol reported was not >= 500 as well as the substance was found to be rapidly degradable.Thus considering the from CLP Criteria for aquatic classification of the substance , it is concluded that Clioquinolcould not exhibit short term toxicity to fish .

So, Clioquinoldoesnot satisfy the environmental effects criterion for classification as toxic (T).


Thus it can be inferred that Clioquinol neither is P & B (including vPvB) substance, nor will qualify as T.