N-phenylmaleimide

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD 403 & GLP. Test substance is micronized from this substance. The commercial product (>355 um) has practically no micronized particle size (<10 um .Test substance is micronized from this substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

N-phenylmaleimide

EC Number:

213-382-0

EC Name:

N-phenylmaleimide

Cas Number:

941-69-5

Molecular formula:

C10H7NO2

IUPAC Name:

1-phenyl-2,5-dihydro-1H-pyrrole-2,5-dione

Details on test material:

Purity:>99.9%
Test substance is micronized from this substance.
The commertial product (>355 um) has practically no micronized particle size (<10 um .

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

whole body

Vehicle:

other: atomise the aceton/water (80/20) solution

Analytical verification of test atmosphere concentrations:

no

Duration of exposure:

4 h

Concentrations:

0.009, 0.016, 0.033, 0.033, 0.044, 0.183 mg/l

No. of animals per sex per dose:

5

Control animals:

no

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

0.034 mg/L air

95% CL:

> 0.031 - < 0.037

Exp. duration:

4 h

Mortality:

Conc (mg/L) M F Total
0.009 0/5 0/5 0/10
0.016 0/5 0/5 0/10
0.033 4/5 1/5 5/10
0.044 4/5 4/5 8/10
0.183 5/5 5/5 10/10

Clinical signs:

other: The signs seen during exposure were considered to be partial closing of the eyes, adoption of a hunched body posture, opening of the mouth during inspiration and exaggerated respiratory movement.

Body weight:

There were moderate to marked decreases of bodyweight or reductions in the rate of bodyweight gain for up to 7 days following exposure to this test substance.

Gross pathology:

The findings for rats that died as a result of exposure to this test substance were typified by congestion of the lungs and/or distension of the gastro-intestinal tract. The latter is commonly seen in rats that die as a result of respiratory difficulties and is due to swallowing of air during attempts to breathe.

Other findings:

Other findings were considered to be within the normal background ranges, and of no toxicological importance.
There were no clear evidence of a sex difference in mortaity due to inhalation of this test substance.

Any other information on results incl. tables

Conc. Date of death (M/F)

Conc. mg/L	0 h	1h	4 h	1 d	2 d	8 d	14 d
0.033	0/0	0/0	0/0	4/1	4/1	4/1	4/1
0.044	0/0	0/0	1/0	4/3	4/3	4/4	4/4
0.183	0/0	2/1	2/4	5/5	5/5	5/5	5/5

Applicant's summary and conclusion

Interpretation of results:

other: This data is not effective to this product due to this product particle is not micronised.

Remarks:

Criteria used for interpretation of results: not specified

Conclusions:

LC = 0.034 mg/L. Test substance is micronized from this substance. The results show that on average, approximately 80% of the PMI present in the chamber
atomosphere was in the form of particle of respirable size (< 5.5 um aerodynamic diameter).
The commertial product (>295 um) has practically no micronized particle size (<10 um) .

Executive summary:

In an acute inhalation toxicity study, groups of young adult albino rats (Sprague-Dawley origin) , 5/sex were exposed by inhalation route to PMI (>99.5% provided by NIPPON SHOKUBAI 7Y09) in acetone/water (80/20) for 4 hours to whole body at concentrations of  0, 0.009, 0.016, 0.033, 0.044, 0.183 mg/L.  Animals then were observed for 14 days.

 

LC₅₀ Combined = 0.034 mg/L (standard error : 0.0033 mg/L)   

PMI is classified as the category 1 in accordance with GHS for acute inhalation toxicity study.

The commertial product (>295 um) has not including any respirable fraction, practically the rsik by inahalation is very low .

However, we should consider the DNEL for inhalation for workers because of any accidental release of this product at polymer manufacturers plant site.