1,6,7,8,9,14,15,16,17,17,18,18-dodecachloropentacyclo[12.2.1.16,9.02,13.05,10]octadeca-7,15-diene

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2002-2003 and 2007

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

publication

Title:

Detection of Dechlorane Plus in Residential Indoor Dust in the City of Ottawa, Canada

Author:

J. Zhu, Y.-L. Feng, M. Shoeib

Year:

2007

Bibliographic source:

Environ. Sci. Technol. 2007, 41, 7694-7698

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Dechlorane Plus was quantitatively determined by GC-MS in samples of dust collected in households in Ottawa area (Canada) from vacuum cleaners. The dust samples were collected from private households in the years 2002 - 2003 (69 samples) and repeatedly in 2007 (7 samples).

GLP compliance:

no

Type of measurement:

background concentration

Media:

other: dust

Test material

Test material information

Constituent 1

Reference substance name:

1,6,7,8,9,14,15,16,17,17,18,18-dodecachloropentacyclo[12.2.1.16,9.02,13.05,10]octadeca-7,15-diene

EC Number:

236-948-9

EC Name:

1,6,7,8,9,14,15,16,17,17,18,18-dodecachloropentacyclo[12.2.1.16,9.02,13.05,10]octadeca-7,15-diene

Cas Number:

13560-89-9

Molecular formula:

C18H12Cl12

IUPAC Name:

1,2,3,4,7,8,9,10,13,13,14,14-dodecachloro-1,4,4a,5,6,6a,7,10,10a,11,12,12a-dodecahydro-1,4:7,10-dimethanodibenzo[a,e][8]annulene

Test material form:

other: dust

Details on test material:

Dechlorane Plus (DP), used as internal standard for instrument calibration was purchased from Cambridge Isotope Laboratories Inc. (Andover, MA).

Study design

Details on sampling:

Dust Samples. Residential homes for the 2002-2003 dust samples, collected during November 2002 to March 2003, were selected randomly according to the procedures described by Zhu, Newhook, R., Marro, L and Chan, C. C. (Selected volatile organic compounds in residential air in the city of Ottawa, Canada. Environ. Sci. Technol. 2005, 39, 3964-3971). Dust samples of year 2007 were collected in the spring from several volunteer's homes. To collect the dust sample, a whole vacuum cleaner bag with the dust content in it was detached from the floor model vacuum cleaners and placed in a polyethylene zip-seal plastic bag [Fisher Scientific, Nepean, Ontario). ln the case of central vacuum systems, dust in the bins was transferred to polyethylene bags (to be brought to the lab) while wearing a powder-free nitrile glove (Tec Choice Nitrile, DiaMed Lab Supplies, Mississauga, Canada). Upon arrival at the laboratory, dust samples were immediately stored at -20 °C. Fine dust for the analysis was obtained by sieving the vacuum dust using an all stainless steel testing sieve VWR I00 mesh for a 150 µm cutoff (VWR International, Montreal, Quebec). The sieved fine dust was stored at -20 °C in a glass jar with a Teflon-lined lid (VWR international, Montreal, Quebec).

Results and discussion

Concentration

Concentration 1

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

14 other: ng/g

Remarks on result:

other: median of samples collected 2002 - 2003 (n = 69)

Concentration 2

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

22 other: ng/g

Remarks on result:

other: median of samples collected 2007 (n = 7)

Concentration 3

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

4.1 other: ng/g

Remarks on result:

other: 5th percentile of samples collected 2002 - 2003 (n = 69)

Concentration 4

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

15 other: ng/g

Remarks on result:

other: 5th percentile of samples collected 2007 (n = 7)

Concentration 5

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

121 other: ng/g

Remarks on result:

other: 95th percentile of samples collected 2002 - 2003 (n = 69)

Concentration 6

Country:

Canada

Location:

Ottawa

Substance or metabolite:

substance

Conc.:

60 other: ng/g

Remarks on result:

other: 95th percentile of samples collected 2007 (n = 7)

Details on results:

The subsequent quantitative measurements of DP in individual dust samples were performed using the selected ion monitoring (SlM) mode of the MS under the same instrumental conditions. DP concentrations reported are the sum of both peaks identified as syn-DP and anti-DP. DP was detected in all indoor dust samples. The concentrations of DP in the 2003-2003 dust samples varied from 2.3 to 182 ng/g, except for one dust sample (5603 ng/g), while the concentrations of DP in the 2007 dust samples varied from 14 to 61 ng/g, well above the method detection limit (MDL) of 0.59 ng /g.
The concentrations of DP in dust did not exhibit a normal distribution. It failed the Kolmogorov-Srnirnov normal distribution test (p = 0.001) with a skewness of 0.273. The log-transformed dataset failed the test too (p = 0.003), but with a lesser skewness of 1.604. A normal distribution dataset would have a skewness of 1.000. The skewed dataset was also evident by the much higher arithmetic mean (AM) value (110 ng/g) compared to the geometric mean (GM) (10 ng/g) or median (14 ng/g) values. Because the measurement of DP was not planned when the dust samples were collected during our 2002 -2003 study on selected volatile organic compounds in Ottawa residences, the questionnaire extracting information on house characteristics and occupant activities administered at the time of sample collection was not specifically designed for the source identification of DP.
Therefore, source identification for the presence of DP in indoor environments could not be conducted, nor would it be possible to explain the extremely high level of DP (5603 ng/g) in one particular house dust sample.

Any other information on results incl. tables

Based on the results from dust samples collected from 2002 - 2003 (as only 7 samples were collected in 2007 these numbers were not considered representative) the estimated human exposure was calculated for children and adults. For Children an average and high dust intake of 55 and 200 mg/d was assumed whereas for adults 4.16 and 100 mg dust uptake/d was assumed. For children, the much lower body weight was also taken into account. The estimated central values of DP daily intake, derived from the average dust ingestion and the median level of DP in house dust, are 0.06 and 0.75 ng/d for adults and children, respectively.

Applicant's summary and conclusion

Conclusions:

Dechlorane plus was found in dust samples collected from private households in Ottawa (Canada) in 2002 - 2003 and 2007. Median concentrations of 14 and 22 ng/g DP in dust were found in 2002 - 2003 and 2007 respectively.

Executive summary:

In this study dust collected from private household vacuum cleaners in the residential area of Ottawa (Canada) was analysed for Dechlorane Plus (DP) content. Median concentrations of 14 and 22 ng/g DP in dust were found in 2002 - 2003 and 2007 respectively. Based on the results from dust samples collected from 2002 - 2003 (as only 7 samples were collected in 2007 these numbers were not considered representative) the estimated human exposure was calculated for children and adults. For Children an average and high dust intake of 55 and 200 mg/d was assumed whereas for adults 4.16 and 100 mg dust uptake/d was assumed. For children, the much lower body weight was also taken into account. The estimated central values of DP daily intake, derived from the average dust ingestion and the median level of DP in house dust, are 0.06 and 0.75 ng/d for adults and children, respectively.