Sodium 3-[{4-[{5-cyano-2,6-bis[(3-methoxyalkyl)amino]alkylpyridin-3-yl}diazenyl]dialkylphenyl}diazenyl]benzenesulfonate

Toxicity to aquatic plants other than algae

Description of key information

At the limit concentration of the test item Acid Red EAY 9656 with nominal 100 mg/L a slight effect was observed on the growth rate and yield (dry weight) of Lemna gibba. The EC10 is > 100 mg/L,the NOEC is >= 100 mg/L

Key value for chemical safety assessment

EC10 or NOEC for freshwater plants:

100 mg/L

Additional information

The effects of test item Acid Red EAY 9656 on the growth of the monocotyledon species Lemna gibba was determined according to the principles of OECD 221.

 

A static exposure over 7 days was carried out. Based on a preliminary test a limit concentration with a nominal loading of 100 mg/L was tested. Six replicates were investigated for the limit concentration and for the control. Frond numbers were assessed on days 0, 2, 5 and 7. Environmental parameters (light intensity, room temperature and pH-value) were within the acceptable limits.The validity criteria of the test guideline were fulfilled.

 

The concentrations of Acid Red EAY 9656of the limit concentration and controlwere analysed via HPLC-DAD at the start (0h) and the end of the exposure (7 days).

The measured concentration at the start of the exposure was 110 % of the nominal value and at the end of the exposure 114 % of the nominal value.

 

NOEC-, LOEC-, EC-Values and 95 % Confidence Intervals ofAcidRed EAY9656after 7 Days

based on nominal test item concentrations [mg/L]

Frond number		Dry weight
Growth Rate Inhibition [mg/L]
NOEC	100	NOEC	100
LOEC	>100	LOEC	>100
ErC10	>100	ErdwC10	>100
ErC20	>100	ErdwC20	>100
ErC50	>100	ErdwC50	>100
Inhibition of Yield [mg/L]
NOEC	100	NOEC	100
LOEC	>100	LOEC	>100
EyC10	>100	EydwC10	>100
EyC20	>100	EydwC20	>100
EyC50	>100	EydwC50	>100