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The impact of this chapter is to inform the reader of this book about current activities of international bodies to improve the methods used in exposure assessment and the knowledge and information database. In addition the reader shall be given insight into the regulatory work and decision procedures.

This chapter focuses on consumer product-related exposure issues. It covers all non-food products that can release chemical substances and consumers may come into contact with. They include, for example, products used inside and around the home for personal hygiene, home maintenance, do it yourself, automotive care, hobby and craft, leisure, playing, home office, pet care, home pesticides, furniture, clothing, and yard and garden maintenance. They are regulated by a number of different regulations (see the following subchapters). Consumer exposures to these products may be direct or indirect. As pointed out in Sect. 3.2.7, they can be characterised by the release of the agent from the source, the transport from the source to the target person (pathway of exposure), and the kind of contact (route of exposure). The release is determined by the chemical’s concentration in an item (consumer product), its properties (e.g. volatility), how it is bonded in the matrix, and what stressors (e.g. temperature, and mechanical activity by the user) are present. These conditions of exposure can be described in general terms in the exposure scenario and by subsequent iterations in a tiered approach. This chapter gives an overview about exposure assessment with regard to consumer products, separated into mixtures and articles. It also focuses on specific issues of exposure assessment with respect to (European) chemicals and cosmetic regulation. Further, this chapter addresses particular issues for exposure estimation of nanoparticles and sprays and aerosols, as well as secondary exposures from house dust.

To reduce the global spread of invasive aquatic species, international regulations will soon require reductions of the number of organisms in ballast water discharged by ships. For this purpose, ballast water treatment systems were developed and approved by an international procedure. These systems rely on established water treatment principles which, to different degrees, have been proven to generate disinfection by-products with hazardous properties but have only scarcely been investigated in marine environments. Our study evaluates the publicly available documentation about approved ballast water treatment systems with regard to by-product formation. The most commonly employed methods are chlorination, ozonation, and ultraviolet (UV) irradiation. Chlorination systems generate trihalomethanes, halogenated acetic acids, and bromate in substantially larger quantities than reported for other areas of application. Levels are highest in brackish water, and brominated species predominate, in particular bromoform and dibromoacetic acid. Ozonation, which is less frequently utilized, produces bromoform in lower concentrations but forms higher levels of bromate, both of which were effectively reduced by active carbon treatment. In systems based on UV radiation, medium pressure lamps are employed as well as UV-induced advanced oxidation. For all UV systems, by-product formation is reported only occasionally. The most notable observations were small increases in nitrite, hydrogen peroxide, halogenated methanes and acetic acids. The assessment of by-product formation during ballast water treatment is limited by the lacking completeness and quality of available information. This concerns the extent and statistical characterisation of chemical analysis as well as the documentation of the test water parameters.

The human genome contains a sequence that is homologous to genes encoding soluble sulphotransferases (SULTs) based on the nucleotide sequence and possible intron/exon splice sites. The putative coding sequence (termed SULT1C3) was synthesized and integrated into a bacterial expression vector. We used the cDNA-expressed protein for raising an antiserum and studying enzyme activities. No activity was detected with 4-nitrophenol and 1-naphthol, known substrates of all other members of the human SULT1 subfamily. The activity was also negligible with paracetamol, ethanol, 5-hydroxymethylfurfural, 2-hydroxymethylpyrene, 2-(alpha-hydroxy)ethylpyrene, and corticosterone, compounds for which we have developed sensitive enzyme assays with direct determination of the product by HPLC-UV, HPLC-fluorescence or HPLC-MS/MS. Since diverse sulpho conjugates are chemically reactive - often short-lived and mutagenic - we expressed SULT1C3 in Ames'Salmonella typhimurium strains TA1538 and TA100, as we had done with many other SULTs previously. The expression level of SULT1C3 protein amounted to 2% of the total cytosolic proteins, which is in the middle range of other SULTs expressed in this model. Using recombinant bacterial tester strains in mutagenicity assays, we observed SULT1C3-mediated activation of several large benzylic alcohols derived from alkylated polycyclic hydrocarbons: 1-hydroxymethylpyrene, both enantiomers of 1-(alpha-hydroxy)ethylpyrene, 6-hydroxymethylbenzo[a]pyrene and 6-hydroxymethylanthanthrene. 1'-Hydroxysafrole was the smallest molecule activated by SULT1C3 up to date. Our study demonstrates that SULT1C3 has sulphotransferase activity and that it prefers relatively large substrates. The substrates detected were activated to mutagens, which cannot be the regular function of the enzyme. The physiological substrates remain to be identified. Probably, they are relatively large, endogenous or common exogenous, molecules.