Brominated organic micro-pollutants in food and environmental biota

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Brominated Flame Retardants as Food Contaminants

Brominated flame retardants (BFRs) are currently the largest market group of flame retardants. The five major BFRs are tetrabromobisphenol-A (TBBP-A), hexabromocyclododecanes (HBCDs), and three commercial mixtures of polybrominated diphenyl ethers (PBDEs), which are known as decabromodiphenyl ether (Deca-BDE), octabromodiphenyl ether (Octa-BDE), and pentabromodiphenyl ether (Penta-BDE). PBDEs, HBCDs, HBCDs and TBBP-A are used in a variety of consumer products, including computers, electronics and electrical equipment, televisions, textiles, foam-padded furniture, insulating foams, and other building materials. Since their introduction about 20 years ago, BFRs are found everywhere in the environment, including in our food. Since the concentrations in food are very low, the chemical analysis of these chemicals is a challenging task with numerous pitfalls.JRC.D.2-Reference material

Contextual Policy Enforcement in Android Programs with Permission Event Graphs

The difference between a malicious and a benign Android application can often be characterised by context and sequence in which certain permissions and APIs are used. We present a new technique for checking temporal properties of the interaction between an application and the Android event system. Our tool can automatically detect sensitive operations being performed without the user's consent, such as recording audio after the stop button is pressed, or accessing an address book in the background. Our work centres around a new abstraction of Android applications, called a Permission Event Graph, which we construct with static analysis, and query using model checking. We evaluate application-independent properties on 152 malicious and 117 benign applications, and application-specific properties on 8 benign and 9 malicious applications. In both cases, we can detect, or prove the absence of malicious behaviour beyond the reach of existing techniques