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An Annex XV restriction dossier for cadmium in artists’ paints was submitted by an EU member state to the European Chemicals Agency ECHA. By cleaning used brushes under the tap cadmium can enter the food chain via waste water treatment and subsequent agricultural application of the sewage sludge. It was estimated that 110 kg Cd per year is spread on agricultural land via this exposure route. Other sources of Cd amount to almost 120 tons per year.
The mobility of Cd from pigments was studied in a field-like scenario by leaching experiments using soil samples amended with sewage sludge and spiked with Cd pigments in percolation columns. The redox conditions were confirmed to be the decisive factor for the release of Cd. The release of Cd from artists’ paints was in most cases 1% or lower in the experiments performed.
Cd from artists’ paints in sewage sludge applied in agriculture will be mobilized for intake by crops or to leaching either by oxidation of sulfide to sulfate or by dissolution at lower pH values. The quantity of Cd from artists’ paints calculated in the restriction dossier is however negligible compared to other sources of Cd to agricultural soil. Therefore ECHA did not consider the proposed restriction to be the most appropriate EU wide measure to address the negligible level of risk. In the presentation sources of Cd on agricultural land will be discussed together with possible policy instruments to mitigate such emissions.
In order to estimating the amount and kind of emissions from polymeric sporting tracks a laboratory test was developed in BAM that combines artificial weathering and subsequent batch and column tests [1, 2, 3]. The goal consisted in nvestigating a possible change of emissions into soil and groundwater of a new sporting ground as a function of ageing and egradation of the system. At various stages of the weathering, the samples were removed and subjected to especially designed column extraction tests for the solid samples. Both these extracts and the accumulated rainwater run-off of the weathering device were subjected to analytical tests of their ingredients. The overall aim of the test consisted in developing ontrollable, reproducible, and standardisable conditions and methods of investigation that would allow an estimation of the emissions in the course of outdoor application of about five years.
Flame retardants are increasingly used in consumer products as e.g. electronics and furniture as well as in construction. Along with the increased usage, concerns about negative effects of flame retardants on human health and the environment have been raised. Concerning construction products one application for flame retardants is the furnishing of steel structures with reactive flameproof coatings. These coatings consist of a complex mixture of different chemicals, additives and solvents. For the evaluation of the risk possibly posed by their application to the environment, this whole mixture should be tested.
Two different leaching tests were applied according to DIN/TS 16637-2 (sample permantly submerged in water) and DIN EN 16105 (immersion and drying cycles), respectively, which can be used for plate-like products. Eluates were divided into subsamples for the measurement of different parameters: pH-value, conductivity, total organic carbon (TOC), cation and anion concentration. For screening of organic compounds, aqueous samples were liquid/liquid extracted using three solvents with different polarity (toluene, hexane and ethylacetate). GC-MS chromatograms were recorded in the SCAN mode and mass spectra of the peaks were compared with spectras stored in the NIST library.
Eluates of leaching test accroding to DIN CEN TS 16637-2 showed low electrical conductivity (20 to 150 µS/cm) and low release of cation and anions often near the LOQ. Diffferences could be observed for plates treated with the reactive coating at both sides and plates coated only at one side, while the other side is only furnished by the corrosive protection layer. Release of TOC and Zn was approx twice or 10 fold higher in the case of plates coated on one side. Furthermore, the comparison of the results for both types of plates showed that a large portion of the released compounds originate rather from the corrosion protection layer than from the reactive coating itself. Leaching tests according to DIN EN 16105 have not been finished yet, but first results show that the conductivity is much lower (1-4 µS/cm) than for the tests according to DIN/TS 16637-2 leading to the assumption that the release of compounds is lower.
By comparison of the mass spectra with library data, mainly organic solvents as xylene, 1-methoxy-2-propanol acetate and n-btuyl carbamate have been tentatively identified so far in the first test fraction done by DIN CEN TS 16637-2.