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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Butyraldehyde has been tested for acute aquatic toxicity in fish, daphnia, alga and bacteria as well as in various protozoa.

Table: Compilation of aquatic toxicity data

Strain

Guideline

Toxicity value

Source

Evaluation

6.1.1  Fish (short-term)

Pimephales promelas (Fathead minnow)

EPA-660/3-75-009

LC50(96h) = 25.8 mg/L

Curtis and Ward 1981

Rel 2

Leuciscus idus (Golden orfe)

DEV, part L15 (draft)

LC50(48h) = 57 mg/L

Juhnke and Lüdemann 1978

Rel. 2

Leuciscus idus (Golden orfe)

DEV, part L15 (draft)

LC50(48h) = 114 mg/L

Juhnke and Lüdemann 1978

Rel. 2

Leuciscus idus (Golden orfe)

DIN 38412 part 15

LC0(48h) =<50 mg/L (Toxicity Threshold)

Wellens 1977 (Hoechst)

Rel 4 (abstract)

Leuciscus idus (Golden orfe)

DIN 38412 part 15

LC0(48h) = 18 mg/L

LC50(48h) = 24 mg/L

Scheubel and Pommer 1980 (Hüls)

Rel 3 (48 h, emulsifier, substance identity questionable)

6.1.2  Fish (long-term)

Poecilia reticulata (guppy)

No data (OECD 204), semi-static

LC50(14d) = 13.7 mg/L

Deneer JW, Seinen W, Hermens JLM (1988)

Rel 2

6.1.3  Invertebrates (short-term)

Daphnia magna

DIN 38412, part 11

EC0(24h) = 100 mg/L

EC50(24h) = 195 mg/L

Bringmann and Kühn 1982

Rel 2

Daphnia magna

Similar to DIN 38412, part 11

EC0(24h) = 120 mg/L

EC50(24h) = 340 mg/L

Bringmann and Kühn 1982

Rel 2

Aedes aegyptilarvae (mosquito)

No data

LC50(4h) = ~1600 mg/L

Kramer et al. 1983

Rel 3 (only 4 h, not validated system, poor documentation)

6.1.5  Alga/Cyanaobacteria

Scenedesmus quadricauda

No data

EC0(8d) = 83 mg/L (MIC)

Bringmann and Kühn 1977/1978a

Rel 3 (methodological deficiencies)

Mixed population with mainlyScenedesmussp.

DEV L12 (1971)

EC10(24h) = 110 mg/L

EC50(24h) = 380 mg/L

Krebs 1991

Rel 3 (methodological deficiencies)

Microcystis aeroginosa

No data

EC0(8d) = 19 mg/L (MIC)

Bringmann and Kühn 1978b

Rel 3 (methodological deficiencies)

6.1.7  Microorganisms

·        Bacteria

Pseudomonas putida

DIN 38412, part 8

EC0(16h) = 100 mg/L (MIC)

Bringmann and Kühn 1977/1980

Rel 2

Pseudomonas fluorescence

DEV L8

EC0(16h) = 100 mg/L (MIC)

Bringmann 1973

Rel 4 (Secondary source)

Activated sludge, domestic

ETAD Fermentation Tube Assay

EC0/EC10(24h) = 150 mg/L (MIC)

Wellens 1777 (Hoechst)

Rel 4 (abstract)

Photobacterium phosphoreum

Microtox test

EC50(15min) = 106.7 mg/L

EC50(5min) = 153.6 mg/L

Chou and Hee

Rel 2

Photobacterium phosphoreum

Microtox test

EC50(5min) = 16.4 mg/L

Curtis et al. 1982

Rel 4 (Secondary source)

·        Protozoans

Uronema parduzci

No data

EC0(20h) = 98 mg/L (MIC)

Bringmann and Kühn 1980/1981

Rel 2

Chilomonas paramaecium

No data

EC0(48h) = 44 mg/L (MIC)

Bringmann and Kühn 1980/1981

Rel 2

Entosiphon sulcatum

No data

EC0(72h) = 4.2 mg/L (MIC)

Bringmann and Kühn 1978/1980/1981

Rel 2

·        Heterogeneous population

Mixed heterotrophic population

DEV L12 (1971)

EC10(24h) = 30 mg/L

EC50(24h) = 60 mg/L

Krebs 1991

Rel 4 (Secondary source)

MIC = minimum inhibitory concentration

Discussion of data

A series of five acute and one 14 day toxicity study were performed with butyraldehyde. The acute toxicity studies were performed over 48 or 96 hours, the LC50 values for the 48 hour exposure period ranged between 24 and 114 mg/L and the 96 hour LC50 was 25.8 mg/L. The 14 day study, conducted with the guppy (Poecilia reticulata) gave an LC50 value of 13.7 mg/L.

Two 24 hour acute toxicity studies were performed withDaphnia magna, the EC50 values were 195 and 340 mg/L. In addition a 4 hour toxicity study was performed withAedes aegyptilarvae (mosquito) and the resulting LC50 was approximately 1600 mg/L.

Three alga / cyanobacteria studies were performed with butyraldehyde. None of the studies were performed according to the current OECD guideline but were considered to be of use on a weight of evidence approach. Studies withScenedesmus quadricaudaandMicrocystis aeroginosaprovided 8 day EC0 values of 83 and 19 mg/L respectively. A study using a mixed algal population (mainlyScenedesussp) gave a 24 hour EC50 of 380 mg/L.

A series of bacteria studies were performed, EC0 values of 100 mg/L were obtained withPseudomonas putidaandPseudomonas fluorescence. In addition microtox test, usingPhotobacterium phosphoreumgave 5 minute EC50 values of 16.4 anf 153.6 mg/L and a 15 minute EC50 of 106.7 mg/L.

Three protozoan species were tested,Uronema parduzci20 hour EC0 of 98 mg/L,Chilomonas paramecium48 hour EC0 44 mg/L andEntosiphon sulcatum72 hour EC0 of 4.2 mg/L. A study conducted on a mixed heterotrophic population provided a 24 hour EC50 of 60 mg/L.

It is recognised that the majority of the studies do not meet the current criteria for standard methods, typically the studies were performed over shorter durations, analysis was not performed and non-standard test species were used. However, the overall pattern of results indicates that butyraldehyde is of low toxicity to aquatic organisms.

The lowest appropriate EC / LC50 obtained was from the study with the guppy, the 96 hour LC50 was 13.7 mg/L which has been to set the aquatic PNEC.

Based on the data set provided the key endpoint for setting the PNEC STP is the 16 hour EC0value of 100 mg/L from the study withPseudomonas putida.