Dibutyl phthalate

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species, other

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: methods are not documented, also lacking testing guidelines

Radiolabelling:

yes

Test organisms (species):

other: Daphnia magna, Gammarus pseudolimnaeus, Chironomus plumosus, Hexagenia bilineata

Route of exposure:

aqueous

Test type:

static

Total exposure / uptake duration:

7 - 14 d

All invertebrates continuously exposed to 14C-di-n-butyl phthalate showed an initial rapid uptake and accumulation of radioactive residues several hundred times greater than the concentration in water (Table 2). With the exception of some species of invertebrates, the accumulation of di-2-ethylhexyl phthalate was greater than that of di-n-butyl phthalate. Di-2-ethylhexyl phthalate residues were

accumulated and stored by scuds during a 14-day exposure at levels 3600 times greater than the 0.1 ,g/l. concentrations in the surrounding water, whereas scuds exposed for 14 days to 0.1 pg/l. of di-n-butyl phthalate accumulated total body concentrations 1400 times the phthalate concentrations in water. Phthalic acid esters were accumulated in invertebrates to a similar degree as that found with the same species of invertebrates exposed to organochlorine insecticides.

Waterfleas (Daphnia magna) were exposed to 0.1 mg/l. of di-n-butyl phthalate for 7 days and then transferred to fresh flowing

water to determine the time required for elimination of phthalate residues. After 3 days, 50% of the total radioactivity remained;

25% of the activity was still present after 7 days in fresh water. Invertebrate metabolism of phthalic acid esters was not determined, and the loss in radioactive residues may have been due to metabolism and/or excretion of the parent compound.

Conclusions:

The low degree of toxicity and the high excretion rate of di-n-butyl and di-2-ethylhexyl phthalates might suggest that these compounds would be relatively safe as far as aquatic organisms are concerned. However, the present data indicate that these compounds can be detrimental to the reproduction of aquatic organisms at low chronic concentrations.

Executive summary:

This is part of a study with DBP and di-2-ethylhexyl phthalate relating to acute toxicity, reproduction and accumulation & excretion. Only the last examinations (accumulation & excretion) concerning DBP are documented here.

Additional information

Based on a log Pow of 4.11 (Leyder & Boulanger 1983) a bioconcentration factor of 780 was calculated (Bysshe 1982).

In 1974 the Environmental Agency Japan conducted studies with DIBP on fish and with water. Water samples showed DIBP levels of 0.16 to 1.2 micrograms per litre. Fish samples showed 150 to 470 micrograms per kilogram. Neither the species nor the applied concentration of DIBP is mentioned. According to the stated values bioaccumulation factors of 125 to 2937 were determined. (Environmental Agency Japan 1985)

Source: Beratergremium für umweltrelevante Altstoffe (BUA) der Gesellschaft deutscher Chemiker: Diisobutylphthalat, BUA-Stoffbericht 201; Dr . H. Behret, Gesellschaft deutscher Chemiker, Postfach 900440, 60444 Frankfurt am Main, Germany; p. 50; ISBN 3-7776-0788-6; S. Hirzel Verlag, Stuttgart 1997