Chlorocresol

Endpoint summary

Additional information

Short-term toxicity to fish:

Based on the various studies available with Klimish rating 2 and 4 for the target substance CAS NO 59-50-7 .The results is summarized as follows

 

Sr.No	Endpoint	Effect values	Basis for effects	Duration	Species	Remarks
1	LC50	6.71 mg/l	mortality	96 hrs	Poecilia reticulata	Data from publication for target chemical
2	LC50	7.56 mg/l	mortality	96 hrs	Pimephales promelas	Data from publication for target chemical
3	LC50	2.2 mg/l	mortality	24 hrs	Poecilia reticulata	Data from publication for target chemical
4	LC50	1 – 3.5 mg/l	mortality	24 hrs	Danio rerio	Data from publication for target chemical

 

By applying weight of evidence approach to the studies summarized in the above table it can be observed that the LC50 values was found to be in range of 1 to 7.56 mg/l in 96 hrs and 24 hrs on the basis of mortality effect . But the BCF value of chlorocresol reported was not >= 2000 as well as the substance was found to be rapidly degradable. Thus according to CLP criteria of aquatic classification it is concluded that the substance chlorocresol is not toxic to fish (Poecilia reticulata,Pimephales promelas,Danio rerio).

However, since this chemical has a harmonized classification as "Aquatic acute 1 " category, for the pupose of chemical safety assessment, this classification shall be considered

Long-term toxicity to fish:

According to annex IX of column I,Long-term toxicity testing on fish need not to be conducted as it is already provided as part of Annex VIII requirements.Therefore this study was considered for waiver.

Short-term toxicity to aquatic invertebrates:

Based on the various studies available with Klimish rating 2 and for target chemical CAS NO 59-50-7 The results is summarized as follows

 

Sr.No	Endpoint	Effect values	Basis for effects	Duration	Species	Remarks
1	LC50	2 mg/l	mortality	48 hrs	Daphnia magna	Data from publication for target chemical
2	LC50	1.5 mg/L.	mortality	48 hrs	Daphnia magna	Data from publication for target chemical
3	LC50	2 mg/L.	mortality	48 hrs	Daphnia magna	Data from study report for target chemical
4	LC50	2.3 mg/L.	mortality	48 hrs	Daphnia magna	Data from study report for target chemical

 

By applying weight of evidence approach to the studies summarized in the above table it can be observed that LC50 value is expected to be in range of 1.5 to 2.3 mg/l in a 48 hrs study on the basis of mortality effect.But the BCF value of chlorocresolreported was not >= 2000 as well as the substance was found to be rapidly degradable. Thus according to CLP criteria of aquatic classification it is concluded that the substance chlorocresol is not toxic to aquatic invertebrate daphnia magna.However, since this chemical has a harmonized classification as "Aquatic acute 1 " category, for the pupose of chemical safety assessment, this classification shall be considered

Long-term toxicity to aquatic invertebrates:

According to column 1 of Annex IX;Long-term toxicity testing on invertebrate was considered for waiver since the information on acute toxicity has already been provided as a part of Annex VII requirements.

Toxicity to aquatic algae and cyanobacteria:

Based on the various studies available with Klimish rating 2 for the target substance CAS NO 59-50-7 The results is summarized as follows

 

Sr.No	Endpoint	Effect values	Basis for effects	Duration	Species	Remarks
1	EC50 EC10 NOEC LOEC	15 mg/l 2.3 mg/l 1.9 mg/l 5.7 mg/l	growth inhibition	72 hrs	Chlorella pyrenoidosa	Data from publication for target chemical
2	EC50 EC10	>10 mg/l 5.2 mg/l	growth inhibition	96 hrs	Scenedesmus subspicatus	Data from publication for target chemical

 

By applying weight of evidence approach to the studies summarized in the above table it can be observed that EC50 value is expected to be in range of10 to15 mg/l and EC10 value was found to be in range of 2.3 – 5.5 mg/l and LOEC And NOEC is 5.7 mg/l and 1.9 mg/l in 96 study on the basis of growth inhibition effect.But the BCF value of Chlorocresolreported was not >= 2000 as well as the substance was found to be rapidly degradable. Thus according to CLP criteria of aquatic classification it is concluded that the substanceChlorocresol is not toxic to to aquatic algae Chlorella pyrenoidosa and Scenedesmus subspicatus

However, since this chemical has a harmonized classification as "Aquatic acute 1 " category, for the pupose of chemical safety assessment, this classification shall be considered

Toxicity to microorganisms:

The IGC50 concentration of chlorocresol in Tetrahymena pyriformis in 60 hours on the basis of growth inhibition effect was observed at dose concentration of 22.86 mg/l.