Evaluation of Bromophenol (BP) Metabolites in Human Urine as Population Exposure Markers for Polybrominated Diphenyl Ethers (PBDEs)
- Hon Wah Michael LAM (Principal Investigator / Project Coordinator)Department of Chemistry
- Margaret Burkhardt MURPHY (Co-Investigator)
- Chris Kong Chu WONG (Co-Investigator)
DescriptionPolybrominated diphenyl ethers (PBDEs) are commonly used brominated flame retardant additives in polymers and textiles and are present in many household appliances and furnishings. Because of their wide application, these compounds are entering our global ecosystem, and humans, at an alarmingly rapid rate, leading them to be formally recognized as persistent organic pollutants (POPs) by the Stockholm Convention. Monitoring human exposure to this class of pollutant is, therefore, very important to the assessment of their risk to society. Although numerous studies have been carried out to trace and assess population exposure to PBDEs in different parts of the world, it can be argued that the reliability of some of these results is limited, mainly due to the difficulty in the acquisition of adequate human tissue samples for measurement, and the bias inherent in limited sample sizes and sampling schemes. Blood and breast milk are the most frequently used human tissues for exposure quantification. Nevertheless, sampling of blood is an intrusive operation and large-scale sampling is usually difficult to achieve. Although breast milk sampling can be regarded as a non-intrusive process, samples are restricted to lactating women within a relatively narrow age distribution, and therefore these results may not reflect population-level exposure. Sampling human urine, on the other hand, is a truly non-intrusive process and it is much easier to obtain a large number of urine samples from voluntary donors for a large-scale population survey. Thus, it would be desirable if metabolites of PBDEs in human urines can be used as exposure markers. Our research team has already obtained preliminary data showing that relatively high concentration of glucuronide and sulfate conjugates of bromophenol (BP) are present in human urine samples. These water-soluble conjugates are known PBDE metabolites and are potential candidate urinary exposure markers for PBDEs. In this project, we will investigate the correlation between the concentrations of these urinary BP metabolites and PBDEs in human blood, as well as measuring concentrations of known PBDE metabolites and selected naturally-occurring bromophenols. Our work will contribute to the development of a more reliable assessment methodology for human PBDE exposure and public health risk assessment.
|Effective start/end date||1/07/10 → 5/03/14|