Cumene

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Result and method described in suffiscient detail. Peer-reviewed publication

Data source

Reference

Reference Type:

publication

Title:

Absorption of cumene through the respiratory tract and excretion of dimethylphenylcarbinol in urin

Author:

Senczuk W, Litewka B

Year:

1976

Bibliographic source:

British Journal of Industrial Medicine 33, 100-105

Materials and methods

Study type:

study with volunteers

Endpoint addressed:

basic toxicokinetics

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

10 healthy volunteers were exposed heads only to defined concentrations of cumene. Absorption of cumene as well as excretion of metabolite 2-phenylpropan-2-ol (=dimethylphenylcarbinol) was measured

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Cumene

EC Number:

202-704-5

EC Name:

Cumene

Cas Number:

98-82-8

Molecular formula:

C9H12

IUPAC Name:

isopropylbenzene

Method

Type of population:

general

Subjects:

- Number of subjects exposed:
- Sex: 5 male, 5 female
- Age: 20-35 years old
- Race: not specified
- Demographic information: Investigations are assumed to be performed in Poland
- Known diseases: healthy according to medical examination

Ethical approval:

not specified

Route of exposure:

inhalation

Reason of exposure:

intentional

Exposure assessment:

measured

Details on exposure:

Each person was exposed to three exposure concentrations at an interval of 10 day
Concentrations tested: 240, 480, and 720 mg/m3
Exposure duration: 8h, divided in two 2.5h and one 2h exposure, with a 30 min break after the exposures

Examinations:

1) Retention of cumene: concentration in inhaled air - concentration in exhaled air
2) Dimethylphenylcarbinol in urine, time of collection of urine: 2.5, 5.5, 8, 10, 12, 14, 24, 32, 40 and 48 h after start of exposure

Results and discussion

Clinical signs:

None

Results of examinations:

Retention of cumene in lungs: 64 % at 0.5 h of exposure, 45 % at the end of the exposure to vapours at 240, 480 and 720 mg/m3;
Excretion of 2-phenylpropan-2-ol in the urine: maximum was observed after 6 to 8 h of exposure, approaching zero after 48 h;
average percentage yield of the conversion of cumene into 2-phenylpropan-2-ol was 35 %.

Any other information on results incl. tables

Cumene absorbed during 8 h exposure

Sex	Cumene in chamber [mg/m3]	Mean absorbed cumene [mg]	Range [mg]
Women	240	270.8	202.0-386.0
	480	526.0	404.0-772.0
	720	789.0	606.0-1158.0
Men	240	466.4	327.0-730.0
	480	934.0	654.0-1460.0
	720	1400.0	981.0-2190.0

Excretion of demethylphenylcarbinol

Sex	Cumene in chamber	Mean excretion [mg]	Range [mg]
Women	100	96.6	73-130.6
	300	219	151.6-343.6
	600	325	201.4-447
Men	100	2.9	1.3-5.3
	300	5.3	2.7-9.6
	600	7.4	2.2-16.0

Applicant's summary and conclusion

Executive summary:

Absorption, metabolism and excretion 10 healthy volunteers (5 men and 5 women) aged between 20 and 35 years were exposed with their heads to 240, 480 and 720 mg cumene/m3 for 8 h periods. Retention of cumene vapours in lungs during exposure decreased from 64 % at 0.5 h of exposure to 45 % at the end of the exposure. Excretion of 2-phenylpropan-2-ol in the urine at different time intervals (2.5 to 48 h after the beginning of exposure) was correlated linearly to the amount of absorbed cumene; excretion time course: a maximum was observed after 6 to 8 h of exposure, excretion decreased after cessation of exposure approaching zero after 48 h; average percentage yield of the conversion of cumene into 2-phenylpropan-2-ol was 35 %.