Phenol, 4-nonyl-, branched

Long-term toxicity to aquatic invertebrates

Description of key information

Comber et al (1993) provided 21-day NOEC (reproduction) of 0.024 mg/L nonylphenol for the preferred species,Daphnia magnain accordance with OECD 202 Guideline methodology.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.024 mg/L

Marine water invertebrates

Marine water invertebrates

Effect concentration:

0.009 mg/L

Additional information

The 21-day study by Comber et al (1993) was selected as the key study because the study provided NOEC values for standard long-term test endpoints of survival and reproduction for the preferred test organism, Daphnia magna, and was adequately documented and performed according to Guidelines. The reported NOEC of 0.05 mg nonylphenol/L by Baldwin et al (1997) and 0.06 mg nonylphenol/L by Brennan et al (2006) for inhibition of reproduction to the preferred test species D. magna was similar to findings of the key study; with Sun and Gu (2005) reporting 0.013 mg nonylphenol/L (no analytical monitoring) at the low end of the range and Brooke (1993) and Spehar et al (2010) reporting 0.12 mg/L at the high end of the range.

Long-term exposure of nonylphenol to aquatic invertebrates included reliable supporting studies covering several different freshwater taxa including the preferred test organism, D. magna. Also, several reliable studies for marine organisms were available, such as Americamysis bahia (Kuhn et al 2001, Hirano et al 2009); Tisbe batagliai (Bechmann, 1999); Tigriopus japonicus (Marcial et al, 2003) and Lytechinus pictus (Taylor, 2019).

The range of NOEC values for survival was from 0.025 mg nonylphenol/L (Sun and Gu, 2005) to 0.04 mg nonylphenol/L (Brennan et al 2006) for D. magna. The NOEC for reproduction ranged from 0.001 mg nonylphenol/L for Ceriodaphnia dubia (7 days) (Isidori et al 2006) to 0.116 mg/l and >0.1 mg nonylphenol/L reported for 21-day tests with D. magna by Brooke (1993) and Scholz (1992), respectively and 0.05mg/l for D. galeata (Tanaka and Nakanishi, 2002). Studies on other freshwater species determined a NOEC for survival of 0.042mg/l for Chironomus tentans (Kahl et al. 1997); a NOEC of >0.2352mg/l for the sediment organism Caenorhabditis elegans (Hoss et al, 2002); a NOEC of >0.005mg/l (the highest concentration tested) for Gammarus fossarum (Geffard, 2010); an EC10 of 0.68mg/l for long term mortality attachment and siphon extension in the freshwater mussel species, Dreissena polymorpha (Quinn, 2006).

For the marine species, the NOEC of 0.0095 mg nonylphenol/L for reproduction (Kuhn et al 2001) of A. Bahia, 0.02 mg nonylphenol/L mortality and reproduction of Tisbe batagliai (Bechmann, 1999) and 0.85mg/l for reproduction of Lytechnius pictus (Taylor, 2019) were within the ranges reported for freshwater organisms.

Insufficient data were available to confirm which of the species tested was most sensitive, but the findings of Isidori et al (2006) suggest that inhibition of reproduction for C. dubia can occur at a concentration lower than reported for D. magna or the marine species tested. Despite this other studies on C.dubia (England, 1995) determined a higher NOEC of 0.1mg/l for this species.

Two additional studies are being carried out during 2019/2020 to investigate the toxicity of nonylphenol on the mudsnail, Potamopyrgus antipodarum (Kimmel) and the oyster, Crassostrea gigas. These studies are investigating long term, reproductive and transgenerational effects.