Dibutyl phthalate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: taken from EU RAR

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2004

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

no data

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dibutyl phthalate

EC Number:

201-557-4

EC Name:

Dibutyl phthalate

Cas Number:

84-74-2

Molecular formula:

C16H22O4

IUPAC Name:

dibutyl phthalate

Details on test material:

A group of 5 m and 5 f Sprague-Dawley rats

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

not specified

Vehicle:

not specified

Details on inhalation exposure:

for 4 hours to an aerosol of 15.68 mg DBP/L of air. Air exposed animals served as controls. Observation period was 14 days. A second delivery of DBP was tested at 12.45 and 16.27 mg/L one month later. Respirable fraction (i.e. diameter <4.7 μm) was 56.9, 64.4 and 59.9% at 15.68, 12.45 and 16.27 mg/L. In the 15.68 mg/L group 2/5 male and 3/5 female animals died, whereas no mortalities were observed in the 12.45 and 16.27 mg/L groups.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Concentrations:

15.68 mg DBP/L of air
12.45 and 16.27 mg/L

No. of animals per sex per dose:

5

Control animals:

yes

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

>= 15.68 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Body weight:

ung/body weight ratios in premature decedents at 15.68 mg/L were elevated, while these ratios were lower than those of controls in males at 12.45 and 16.27 mg/L.

Any other information on results incl. tables

Due to the unusual death pattern, no LC50 value could be determined, but the LC50 value was estimated to be ≥15.68 mg/L in this study which was performed under GLP conditions. At 15.68 mg/L apart from a reduction in respiratory rate, behaviour of the rats showed no differences with control animals. Poor coat condition was seen in all surviving animals during the observation period due to excessive grooming behaviour. Lung/body weight ratios in premature decedents at 15.68 mg/L were elevated, while these ratios were lower than those of controls in males at 12.45 and 16.27 mg/L. Macroscopy of the lungs revealed red/dark foci in several animals scattered among the treatment groups. One m and one f rat exposed to 15.68 mg/L had white foci in all lung lobes. Dark red areas were seen in the lungs of 2 females at 12.45 mg/L and in 1 male and 1 female rat at 16. 27 mg/L.