Reaction products of orthoboric acid with 2,2'-iminodiethanol (1:1)

Toxicity to aquatic algae and cyanobacteria

Description of key information

Under the conditions of the present study with Pseudokirchneriella subcapitata,  MEA Polyborate 1:1  reduced growth rate and inhibited the yield of this fresh water algae species significantly at 10 mg a.i./l  and higher.
Suitable for read-across for DEA Polyborate
The EC50 for growth rate reduction (ERC50: 0-72h) was 26 mg a.i./l  with a 95 % confidence interval ranging from 21 to 31 mg a.i./l.
The EC50 for yield inhibition (EYC50: 0-72h) was 13 mg a.i./l  with a 95 % confidence interval ranging from 5.2 to 30 mg a.i./l. These values are used as estimates of the short-term or acute toxicity of the test substance, per the OECD guidelines.
The NOEC for growth rate reduction and yield inhibition was 3.2 mg a.i./l. These values are used as estimates of the long-term or chronic toxicity of the test substance, per the OECD guidelines.
Under the conditions of the present study with Pseudokirchneriella subcapitata, MEA Polyborate 1:3 reduced growth rate and inhibited the yield of this fresh water algae species significantly at 32 mg a.i./l  and higher.
The EC50 for growth rate reduction (ERC50: 0-72h) was 67 mg a.i./l  with a 95 % confidence interval ranging from 52 to 85 mg a.i./l.
The EC50 for yield inhibition (EYC50: 0-72h) was 32 mg a.i./l  with a 95 % confidence interval ranging from 21 to 47 mg a.i./l. These values are used as estimates of the short-term or acute toxicity of the test substance, per the OECD guidelines.
The NOEC for both growth rate reduction and yield inhibition was 18 mg a.i./l. These values are used as estimates of the long-term or chronic toxicity of the test substance, per the OECD guidelines.

Key value for chemical safety assessment

EC50 for freshwater algae:

26 mg/L