Abstract

This thesis dissertation examines the presence and exposure of two classes of compounds; polybrominated diphenyl ethers (PBDEs) and polyfluorinated compounds (PFCs). Both classes are considered persistent organic pollutants as they are toxic, bio-accumulative and have a high susceptibility to be environmentally dispersed. The PBDEs are typically used as protective agents on household appliances and furniture to retard the startup of fires; PFCs on the other hand are used as oil and water repellants. Few studies have investigated the presence of polybrominated diphnely ethers (PBDEs), novel flame retardants (FRs / non-PBDEs) and poly- and perfluoroalkyl compounds in Africa and the Middle East. These compounds have become ubiquitous, not only found in humans but also in animals and wildlife. Researches have shown that these toxic compounds can cause cancer, affect neurodevelopment, growth and other possible health risk. The main aim of this thesis was to investigate the levels of these contaminants and assess their associated human health risk. The levels of fourteen PBDE congeners and eleven non-PBDE flame retardants were investigated in 17 homes, 9 workplaces and 5 cars in the greater Cairo region. GC-MS was used for both the separation and quantification of the target analytes. Several parameters were calculated including the mean, median, minimum, maximum and four different percentiles. The median ΣPBDE concentrations were 57, 425 and 1608 ng g−1 in homes, workplaces and cars respectively. It was observed that congener 209 was dominant in all samples in the three different microenvironments with a median concentration of 40.2, 366 and 1540 ng g−1 in homes, workplaces and cars respectively representing 70 to 95% of the total PBDEs. Several novel PBDEs were investigated including hexabromocyclododecane (HBCD), hexabromobenzene (HBB), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), bis (2-ethyl-1-hexyl) tetrabromophthalate (TBPH), 1,2-bis (2,4,6-tribromophenoxy) ethane (TBPE), ally-2,4,6-tribromophenyl ether (ATE) and Dechlorane Plus (DP). The Σnon-PBDEs median concentrations were 8.30, 28.9 and 49.9 ng g−1 in homes, workplaces and cars respectively with HBCD predominating. Four groups of analytes were investigated in the PFCs including: fluorotelomer acrylates (FTA), fluorotelomer alcohols (FTOH), Methyl/Ethyl perfluorooctane sulfonamides (Me/Et FOSA), Methyl/Ethyl perfluorooctane sulfonamidoethanols (Me/Et FOSE). Concentration of the PFASs ranged from 1.3 to 69 ng g−1 with FTOHs being the dominant. The highest FTOH was 8:2 FTOH detected in all samples in the three microenvironments. Results show that levels of PBDEs, non-PBDEs and PFCs in the Egyptian dust were among the lowest worldwide. Different dust exposure scenarios using 5th percentile, median, 95th percentile and maximum levels were estimated for adult and children. The estimated dust intake results were several orders of magnitude lower than the oral reference dose values.

Department

Chemistry Department

Degree Name

MS in Chemistry

Graduation Date

6-1-2015

Submission Date

May 2015

First Advisor

Shoeib, Tamer

Committee Member 1

Sayed, Nagla Ali

Committee Member 2

El-Gendy, Ahmed Shafik

Extent

102 p.

Document Type

Master's Thesis

Library of Congress Subject Heading 1

Fireproofing agents -- Egypt -- Cairo.

Library of Congress Subject Heading 2

Polybrominated diphenyl ethers -- Egypt -- Cairo.

Rights

The author retains all rights with regard to copyright. The author certifies that written permission from the owner(s) of third-party copyrighted matter included in the thesis, dissertation, paper, or record of study has been obtained. The author further certifies that IRB approval has been obtained for this thesis, or that IRB approval is not necessary for this thesis. Insofar as this thesis, dissertation, paper, or record of study is an educational record as defined in the Family Educational Rights and Privacy Act (FERPA) (20 USC 1232g), the author has granted consent to disclosure of it to anyone who requests a copy.

Institutional Review Board (IRB) Approval

Approval has been obtained for this item

Comments

Laboratory Instruction Graduate Fellowship AUC, Travel Abroad Grant AUC, Environment Canada, Toronto, Ontario

Download

Share

COinS