2,7-Naphthalenedisulfonic acid, 4-amino-3,6-bis[2-[4-(ethenylsulfonyl)phenyl]diazenyl]-5-hydroxy-, sodium salt (1:2)

Long-term toxicity to fish

Description of key information

Long-term toxicity in fish: LC10 > 100 mg/L; NOEC for behavioural effects: 10 mg/L after 28-days of exposure with Reactive Black 5-OH. No effects up to 100 mg/L after 14 days of exposure with Reactive Black 5 bis-ester.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

10 mg/L

Additional information

Reactive Black 5-OH, the hydrolysis product of Reactive 5 bis-vinyl, was tested for long-term effects in zebrafish over an exposure period of 28 days at dose levls of 10 to 100 mg/L according to OECD 204. All fish survived the 28-day exposure period. One fish of the 100-mg/L group died on the first post-exposure day. At 100 mg/L, tail-heavy swimming attitude, gill cover sticking out, increased respiratory rate, increased activity and increased startle response were observed. Fish at this dose group had a reduced food consumption. At 33 mg/L, increased respiratory rate and reduced food consumption were observed. At 10 mg/L, there were no adverse effects observed. The limit concentration for mortality was 100 mg/L, the limit concentration for adverse effects was 33 mg/L. Hence, the NOEC for this study for behavioural effects was 10 mg/L, for mortality 100 mg/L.

In another test performed by the MOE, Japan, Reactive Black 5 in its bis-ester form, was thested in a 14-day subacute toxicity test in fish according to OECD guideline No. 204 in Oryzias latipes. In this test, neither effects on behavior nor deaths were observed at test substance concentrations up to 100 mg/L. Hence, Reactive Black 5 is not toxic to fish in the 14-day test.