Triethyl phosphate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.632 mg/L

Assessment factor:

50

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

9 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.063 mg/L

Assessment factor:

500

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

298.5 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

5 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.5 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

0.64 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

Toxicity to fish

Ewell et al (1986) describe the development of a test system designed to simultaneously assess the aquatic toxicity of chemicals to seven species, including six invertebrate species. Under the conditions of this study, the 96 -hour LC50 of triethyl phosphate in the fathead minnow was reported to be >100 mg/L. The acute toxicity of triethylphosphate was investigated in the bleak (Alburnus alburnus). The 96 -hour LC50 value of the substance was calculated to be 2100 -2400 mg/L (Linden et al, 1978). The acute aquatic toxicity was investigated in Oryzias latipes. The 48 -hour LC50 of the substance is reported to be >500 mg/L (CITI, 1992). The acute toxicity of triethyl phosphate was investiagted in Leuciscus idus. The 48 -hour LC0, LC50 and LC100 values were found to be 1926 mg/L, 2140 mg/L and 2500 mg/L under the conditions of this study (Knie et al, 1983). The acute toxicity of triethylphosphate was investigated in Danio rerio. No deaths occurred at concentrations of up to and including the highest tested concentration of 100 mg/L. The 96 -hour LC50 of triethylphosphate in Danio rerio is therefore >100 mg/L (Bayer, 1985a). The acute toxicity of triethylphosphate was also investigated in Leuciscus idus. 50% mortality was seen in an initial study performed at 100 mg/L, however no effects were seen in subsequent experiments at 133 or 100 mg/L. The LC50 is therefore considered to be >= 100 mg/L (Bayer, 1985b). A waiver is proposed for long-term toxicity to fish, on exposure grounds.

Toxicity to aquatic invertebrates

Bringmann & Kuehn (1982) describe an improved standardised procedure for the assessment of the toxic effects of chemicals on Daphnia magna. The 24 -hour EC0, EC50 and EC100 values for Daphnia magna (immobilisation) were calculated to be 603 mg/L, 900 (841 -1061) mg/L and 1250 mg/L respectively, under the conditions of this study. Ewell et al (1986) describe the development of a test system designed to simultaneously assess the aquatic toxicity of chemicals to seven species, including six invertebrate species. Under the conditions of this study, the 96 -hour LC50 of triethyl phosphate in the invertebrate species tested [Asellus intermedius (pillbug), Daphnia magna (water flea), Dugesia tigrina (flatworm), Gammarus fasciatus (sideswimmer), Helisoma trivolvis (snail) and Lumbriculus variegatus (segmented worm)] were all reported to b >100 mg/L. Knie et al (1983) report the results of a series of aquatic toxicity tests with various chemicals. EC0, EC50 and EC 100 values for triethyl phosphate in Daphnia magna of 500, 950 and 1500 mg/L respectively are reported. The acute toxicity of triethyphosphate was assesed in Daphnia magna Straus in a range-finding study for the reproductive toxicity study. The 24 -hour EC0, EC50 and EC100 values for triethyphosphate in Daphnia magna were found to be 1000 mg/L, 2705 mg/L and 5000 mg/L respectively, under the conditions of this test (Bayer, 1987).

The reproduction of Daphnia was adversely affected by exposure to the test substance only at concentrations of 100 mg/L and higher. The EC50 for reproduction in Daphnia magna was calculated to be 729 mg/L under the conditions of this study. A NOEC of 31.6 mg/L was shown (Bayer, 1987).

Toxicity to algae

The acute toxicity of triethyl phosphate was investigated in Scenedesmus subspicatus. The 72 -hour EC10, EC50 and EC90 values were calculated to be 127, 901 and 6396 mg/L, respectively (Bayer, 1987). A waiver is proposed for long-term toxicity, on expousre grounds.

Toxicity to micro-organisms

The bacterial toxicity of triethylphosphate was assessed in Pseudomonas putida by measurment of oxygen consumption (Robra, 1976). The EC10 is reported to be 2985 mg/L.

Conclusion on classification

No classification for the environment is needed as observed effect concentrations are rather high exceeding the limit values given by the CLP regulation.

A classification according to H413 ("safety net") can be ruled out as the substance has a rather high water solubiity and bioaccumulation is negligible.