Formaldehyde

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to fish, other

Data waiving:

other justification

Justification for data waiving:

other:

Description of key information

No data from guideline studies on chronic fish toxicity is available. According to Annex IX of the Regulation (EC) No 1907/2006 tests should be proposed if the chemical safety assessment indicates the need to investigate further the effects on fish. The acute data set of the test item is extensive and complete, covering all trophic levels with revealing algae and aquatic invertebrates being more sensitive to the test item than fish. Furthermore, the test item is not bioaccumulative, readily biodegradable and undergoes complete hydration. In order to this, the test item is only available to a very low extend in the system and a long term- exposure of aquatic organisms to the test item is very unlikely. Accordingly, further testing is not warranted. 

Additional information

No data from guideline studies on chronic fish toxicity is available. According to Annex IX of the Regulation (EC) No 1907/2006 tests should be proposed if the chemical safety assessment indicates the need to investigate further the effects on fish. The acute data set of the test item is extensive and complete, covering all trophic levels with revealing algae and aquatic invertebrates being more sensitive to the test item than fish (algae: EC50(72h) = 4.89 mg/L, Daphnia pulex EC50(48 h) = 5.8 mg/L, fish acute LC50 = 24.1 mg/L). In addition, chronic data for invertebrates are available which indicates no chronic effects on aquatic invertebrates of the test item. Furthermore, the test item is not bioaccumulative, readily biodegradable and undergoes complete hydration.

Since the test item is readily biodegradable it will rapidly disappear from water. A chronic exposure of aquatic organisms is therefore unlikely and testing not necessary.

Nevertheless, a study on the effects of the test item to embryos-larval stages of Danio rerio exposed to five concentrations of the test item is available, investigating the effects of water chemistry to hatching success and survival (Meinelt et al. 2005). This study is not in accordance with current guidelines (e.g. exposure duration 144 hours) and does not measure relevant chronic effect concentrations (e.g. NOEC, LOEC or EC10). Therefore, this study is not appropriate as key study. Nevertheless, typical endpoints of chronic fish tests are met (e.g. hatching) hence this study can be used to support the justification of data waiving.

 After 144 hours, most of the embryos in the test medium with natural organic matter (NOM) at lower formaldehyde concentrations hatched, whereas embryos in the test media without natural organic matter (NOM) did not. It was concluded that toxicity of formaldehyde is influenced by water chemistry. Under the experimental conditions applied, the lowest LC50 was 6.9 mg/L.

Furthermore, a juvenile growth test similar to OECD 215 using Oryzias latipes as test organism was conducted (Johnson et al., 1993). Formaldehyde did not cause any target organ pathologies even in the highest exposure concentration (48 mg/L), when tested over a period of 28 d. There were also no significant growth or survival effects at this concentration.

In conclusion, based on available chronic data for aquatic invertebrates and supporting long-term data for fish no long-term effects on fish are expected. Due fast degradation and complete hydration the exposure of the test item to fish is very low and further experimental studies may possibly refine the assessment but will not change its main conclusions. Therefore, additional testing on vertebrates would violate the requirements of animal welfare.