Consumer exposure to biocides - identification of relevant sources and evaluation of possible health effects

<p>Abstract</p> <p>Background</p> <p>Products containing biocides are used for a variety of purposes in the home environment. To assess potential health risks, data on products containing biocides were gathered by means of a market survey, exposures were estimated using a worst case scenario approach (screening), the hazard of the active components were evaluated, and a preliminary risk assessment was conducted.</p> <p>Methods</p> <p>Information on biocide-containing products was collected by on-site research, by an internet inquiry as well as research into databases and lists of active substances. Twenty active substances were selected for detailed investigation. The products containing these substances were subsequently classified by range of application; typical concentrations were derived. Potential exposures were then estimated using a worst case scenario approach according to the European Commission's Technical Guidance Document on Risk Assessment. Relevant combinations of scenarios and active substances were identified. The toxicological data for these substances were compiled in substance dossiers. For estimating risks, the margins of exposure (MOEs) were determined.</p> <p>Results</p> <p>Numerous consumer products were found to contain biocides. However, it appeared that only a limited number of biocidal active substances or groups of biocidal active substances were being used. The lowest MOEs for dermal exposure or exposure by inhalation were obtained for the following scenarios and biocides: indoor pest control using sprays, stickers or evaporators (chlorpyrifos, dichlorvos) and spraying of disinfectants as well as cleaning of surfaces with concentrates (hydrogen peroxide, formaldehyde, glutardialdehyde). The risk from aggregate exposure to individual biocides via different exposure scenarios was higher than the highest single exposure on average by a factor of three. From the 20 biocides assessed 10 had skin-sensitizing properties. The biocides isothiazolinone (mixture of 5-chloro-2-methyl-2H-isothiazolin-3-one and 2-methyl-2H-isothiazolin-3-one, CMI/MI), glutardialdehyde, formaldehyde and chloroacetamide may be present in household products in concentrations which have induced sensitization in experimental studies.</p> <p>Conclusions</p> <p>Exposure to biocides from household products may contribute to induction of sensitization in the population. The use of biocides in consumer products should be carefully evaluated. Detailed risk assessments will become available within the framework of the EU Biocides Directive.</p

Multifunctional Nanoparticles by Coordinative Self-Assembly of His-Tagged Units with Metal–Organic Frameworks

Self-assembly of individual units into multicomponent complexes is a powerful approach for the generation of functional superstructures. We present the coordinative interaction of oligohistidine-tags (His-tags) with metal-organic framework nanoparticles (MOF NPs). By this novel concept, different molecular units can be anchored on the outer surface of MOF NPs in a self-assembly process generating multifunctional nanosystems. The article focuses on two main objectives: first, the detailed investigation of the assembly process and fundamental establishment of the novel functionalization concept; and second, its subsequent use for the development of biomacromolecule (e.g., peptides and proteins) delivery vehicles. Three exemplary MOF structures, MIL-88A, HKUST-1, and Zr-fum, based on different metal components, were selected for the external binding of various His-tagged synthetic peptides and recombinant or chemically H6-modified proteins. Evidence for simultaneous assembly of different functional units with Zr-fum MOF NPs as well as their successful transport into living cells illustrate the promising potential of the self-assembly approach for the generation of multifunctional NPs and future biological applications. Taking the high number of possible MOF NPs and different functional units into account, the reported functionalization approach opens great flexibility for the targeted synthesis of multifunctional NPs for specific purposes

Organophosphate im Vollblut (Chlorpyrifos, Diazinon, Fenitrothion, Fenthion, Malathion)

Das hier beschriebene Verfahren erlaubt die Bestimmung der Organophosphat-Insektizide Chlorpyrifos, Diazinon, Fenitrothion, Fenthion sowie Malathion im Vollblut. Dabei können arbeitsmedizinisch relevante Expositionen gegenüber diesen Organophosphaten erfasst werden. Hierzu wird EDTA-stabilisiertes Vollblut im Ultraschallbad hämolysiert. Die enthaltenen Organophosphate werden an Kieselgurkartuschen (Extrelut NT 20) angereichert und aufgereinigt. Nach der Elution werden die Analyten im Stickstoffstrom aufkonzentriert. Die Messung erfolgt nach kapillargaschromatographischer Trennung mit einem massenselektiven Detektor und Elektronenstossionisation (EI). Die quantitative Auswertung erfolgt an Kalibriergeraden mittels Vergleichsstandards, die mit Hilfe von gepoolten Humanblut hergestellt werden. Diese Standards werden in gleicher Weise behandelt wie die zu untersuchenden Vollblutproben. Als Interner Standard wird den Blutproben Chlorpyrifos-Diethyl-D10 zugesetzt. Die Nachweisgrenze der Methode liegt für die einzelnen Organophosphate zwischen 0,5 und 2,6 ng pro Liter Blut

Hecken und Flurgehölze - Struktur, Funktion und Bewertung

Symposium Bayreuth, 17.-19.5.198

Development of a GC-MS method for the determination of household insecticides in indoor air

This work presents a GC-MS method for the determination of 17 household insecticides and acaricides in indoor air. Air samples were collected with a sampling train which consisted of a glass fibre filter and two polyurethane foam plugs, followed by a high-volume air pump. Filters and plugs were analysed separately. The overall recoveries ranged from 85 to 109% (4-11% RSD). Minimum method detection limits between 0.1 and 5 ng/m3 were determined

Unexpected brain lesions in lactating Sprague-Dawley rats in a two-generation inhalation reproductive toxicity study with pentafluoropropane (HFC-245fa)

The study presented was conducted following the reproductive study guideline OECD Guideline 416 Two-Generation Reproduction Toxicity Study. Sprague-Dawley rats were exposed to 2000, 10,000 and 50,000ppm of HFC-245fa. There was an unexpected mortality of lactating dams in the medium and high dose group beginning at day 10 of lactation. Statistically significant histopathological alterations were observed in the cerebellum of a total of 9/30 females of the high dose group of the F0-generation and in 10/27 females of the high dose group of the F1-generation. In contrast there were no brain lesions found in males or non-pregnant females of all dose groups. Neuronal necrosis and degeneration in the cerebellar cortex were observed as the most severe finding. Furthermore vacuolation of the neuropil in different degrees was diagnosed in 7/30 females of the F0-generation and in 9/30 females of the F1-generation. Acute hemorrhages - in particular perivascular - occurred in 5/30 f emales of the F0- and in 5/30 females of the F1-generation indicating a disturbed vascular integrity. The main lesions found in the cerebrum were glial scars in the corpus callosum and restricted to 2/30 females of the F0-generation of the high dose group. The increased incidence of myocardial fibrosis and mononuclear cell infiltration in males - indicating myocarditis - was only seen in the F0-generation of the high dose group. Females of the F1-generation of the high dose group showed an increased incidence of minimal myocardial fibrosis. In summary, histopathology revealed that the brain, particularly the cerebellum, and to a minor degree the heart turned out to be the toxicological target organs of the substance. Presumably substance-related energy deprivation may be responsible for the observed changes. One of the metabolites, 3,3,3-trifluoropropanoic acid has been shown to be capable of causing this effect