Bis(2-ethylhexyl) phthalate

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: 2.e: Study well documented and based on generally well accepted scientific principles. Representative data, enough exposure contextual information and accepted sampling and analytical method.

Data source

Reference

Reference Type:

publication

Title:

Investigation of volatile organic compounds and phthalates present in the cabin air of used private cars.

Author:

Geiss O., Tirendi S., Barrero-Moreno J., and Kotzias D.

Year:

2009

Bibliographic source:

Environment International, 35, 1188-1195.

Materials and methods

Type of study / information:

Consumer exposure to DEHP released from articles in indoor air of private cars.

Principles of method if other than guideline:

DEHP release in indoor air in eighteen private cars was investigated during the summer and the winter for seven days.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Bis(2-ethylhexyl) phthalate

EC Number:

204-211-0

EC Name:

Bis(2-ethylhexyl) phthalate

Cas Number:

117-81-7

Molecular formula:

C24H38O4

IUPAC Name:

1,2-bis(2-ethylhexyl) benzene-1,2-dicarboxylate

Method

Ethical approval:

not applicable

Remarks:

but approved by the investigated population

Details on study design:

Vehicles under study were from colleagues from the authors of the study who volunteered to take part into the investigation. Driving habbits (smoking, use of deodorizer, open windows and the average daily driving time) and main characteristics of the cars were established for all drivers. Indoor temperature was established for two vehicles parked in garage and outside, and no significant difference was observed.

Exposure assessment:

measured

Details on exposure:

TYPE OF EXPOSURE: Inhalation of DEHP in indoor air of private cars

TYPE OF EXPOSURE MEASUREMENT: Area air sampling, seven measurements of 16 hours each.


EXPOSURE LEVELS: cf results


EXPOSURE PERIOD: Drivers stated to stay between 10 and one hundred and twenty minutes in their car per day. Besides, release of DEHP in air was monitored for 16 hours starting form the late afternoon and up to 16 hours.


DESCRIPTION / DELINEATION OF EXPOSURE GROUPS / CATEGORIES: All participants lived within a maximum of 20 km from Ispra (Italy) and none of them lived in a city.

No further information

Results and discussion

Results:

Concentration in Bis(2-ethyl hexyl) phthalate in the air of vehicle cabins was below the detection limit for twelve of the eighteen investigated cars. For the remaining six cars, concentration in DEHP in the air of vehicle cabins ranged from 335 to 3656 ng/m³ air. At the time of investigation, all cars, where DEHP was detected, were between two or seven years old.

Applicant's summary and conclusion

Conclusions:

In the test conditions, the authors reported that concentration in DEHP in the air of vehicle cabins ranged from 335 to 3656 ng/m³ air in six of the investigated cars. For the twelve remaining cars, DEHP was below the detection limit (150 ng/m³ air). These data brings evidence that customers are weakly exposed to DEHP when driving their cars in Winter.

Executive summary:

Bis(2 -ethylhexyl) phthalate (CAS n° 117 -81 -7 ) release in indoor air of eighteen private cars was investigated during the summer and the winter of 2007 for seven days. Vehicles under study were from colleagues from the authors of the study who volunteered to take part into the investigation. Driving habbits (smoking, use of deodorizer, open windows and the average daily driving time) and main characteristics of the cars were established for all drivers. Besides, indoor temperature was established for two vehicles during the sampling period (parked in a garage and parked outside).

Phthalates in the cabin air were measured by placing pumps on the back seat of the vehicles for approximately 16h, thus trapping about 1m³ air in the sampling tubes. The average flow was approximately 1 L.min−1. The sampling tubes were OVS-tenax sampling tubes (SKC, Cat No. 226-56) containing a glass fibre filter and two sections of tenax adsorbent separated by a foam plug. The measurements were made during the months of November and December 2007 and were not repeated in summer. The total number of samples is not clear. But considering the number of cars included in the study, this would lead to eighteen samples.

OSHA (Occupational Safety and Health Administration) method 104 for the determination of phthalates in the air was adapted to the needs of the measurements. DEHP was then desorbed by toluene and the extraction solution was then analysed by gas chromatography and flame ionisation detection. The absolute detection limit was determined as being 50 ng.mL−1 extraction solution for all compounds. Extracting with 3 mL of extraction solution and sampling a volume of air of approximately 1000 L lead to a detection limit of 150 ng/m³.

Hence, in the test conditions, no significant difference was observed on the indoor temperature during the sampling period (winter). Besides,concentration in bis(2-ethyl hexyl) phthalate in the air of vehicle cabins was below the detection limit for twelve of the eighteen investigated cars. For the remaining six cars, concentration in DEHP in the air of vehicle cabins ranged from 335 to 3656 ng/m³ air over the sampling period. At the time of investigation, all cars, where DEHP was detected, were between two or seven years old. More importantly, it appears that none of the cars investigated having leather upholstery (three) had DEHP detected in the cabin air during a sixteen hours sampling period. After calculation (not performed by the authors), the median exposure is at 150 ng/m³, the mean exposure level around 517 ng/m³ and the 95 th percentile at 2450 ng/m³.

It is well clear then that the level of exposure in indoor air of cars is dependant of the investigated vehicle and the season. Thus, data on release of DEHP during the winter would have conforted this hypothesis. Howver, the driving habbit reveals that the exposure period to DEHP ranged from 10 min to 2 hours a day for a normal customer (n=18). Hence, the real exposure level should be lower than the range given here. These data brings evidence that customers are weakly exposed to DEHP when driving their cars.

The analytical and sampling methods are well accepted methods and sufficiently documented. Besides, sufficient information are given on the contect of exposure. Altogether, these elements prove that this study is well described and is based on generaly well accepted scientific principles. The study is then reliable with restrictions.