| Abstract Title: | Evaluation of Dried Milk Spots (DMS) for Mercury Analysis in Human Breastmilk |
| Presenter Name: | Christopher Bake vel Bakin |
| Company/Institution: | Klinikum der Universität München |
| Session: | Human Exposure and Risk Assessment of Hg |
| Co-Authors: | Christopher Bake vel Bakin,Stephan Bose-O'Reilly,Stefan Rakete |
Abstract Information :
Background: Most common matrices for the evaluation of the exposure to mercury are blood, urine, hair and also breastmilk. Usually, liquid breastmilk is used for the analysis, which requires a constant cooling chain for transport and storage. This fundamental condition is a well-known issue, especially in low- and middle-income-countries with limited laboratory capacities. Therefore, the goal of this study was the evaluation of so-called ?Dried Milk Spots? (DMS) on filter paper cards for the analysis of mercury in human breastmilk. Methods: All samples were analyzed by direct mercury analysis. DMS were prepared by pipetting breastmilk samples onto filter paper cards. For method development, reference or spiked breastmilk samples with different mercury concentrations were used. Furthermore, storage stability of DMS was evaluated for multiple storage conditions such as the storage container. For the evaluation of DMS under field conditions, breastmilk samples from breastfeeding women were collected at paediatric practices in the Munich metropolitan area. Immediately after the sampling, DMS were prepared, stored and analyzed after one week of storage. Liquid breast milk samples were directly analyzed. Results and discussion: Both plastic bags and pre-cleaned glass tubes were suitable for sample storage at different temperatures and times, showing recoveries compared to the liquid samples of 91-107 %. The limit of detection (LOD) of mercury in DMS was 0.3 æg/l. Unfortunately, the evaluation DMS under field conditions was limited as the majority of the collected breast milk samples was below LOD. Summary: DMS are generally suitable for mercury analysis in breastmilk. The storage at room temperature makes DMS a promising sampling technique for its application in low- and middle-income-countries. Although the sensitivity may be too low for mercury analysis in low-exposed populations, DMS may be used in areas with a high environmental exposure to mercury, e.g. in artisanal and small-scale gold mining areas.
