UV filters

Miscellaneous. The reaction products of sahcylaldehyde with certain compounds containing active methylene groups, eg, acetylacetone, are excellent uv absorbers. Films containing these compounds can be used as uv filters to protect light-sensitive foods, wood products, paper, dyes, fibers, and plastics (95). 

Although the EEC is stiU in the process of completing cosmetic regulation, the final directive is expected to require member states to ban marketing of cosmetics that contain prohibited ingredients, an amount of a substance in excess of that proscribed, coloring agents, preservatives, or uv filters not specifically allowed. 

The smaller the particle size, the lower the wavelength at which maximum scattering occurs. Thus, ultrafine (20-50nm) T1O2 is used as a UV filter in skin care and cosmetic products. (Sec V. P. S. Jl din, Chem. Br. 29, 503-5 (1993).)... 

The use of a UV filter or alternate visible light source is the next step to ensure that no UV induced reactions are occurring in parallel with the photocatalytic process. 

UV-filters River, lake and treated wastewater SBSE... 

PPCPs 4 preservatives, 2 antimicrobials and 5 UV filters Surface and wastewaters SPE (Oasis HLB and Bond Elute Plexa... 

Sometimes for some very potent pollutants analytical methodologies provide limits of detection (LODs) higher than the concentrations that cause effects, as derived from ecotoxicological studies. Therefore efforts in the field of analytical chemistry (see Sect. 2) are focused on making available the necessary analytical capabilities to detect pollutants at the required low levels found in the environment. This was the case of pharmaceuticals, illicit drugs, perfluorinated compounds (PFCs), sunscreens/UV filters, etc. few years ago. However, this list is likely to increase with new family candidates. 

Rodil R, Moeder M (2008) Development of a method for the determination of UV filters in water samples using stir bar sorptive extraction and thermal desorption-gas chromatography-mass spectrometry. J Chromatogr A 1179(2) 81—88... 

Gago-Ferrero P, Diaz-Cruz MS, Barcelo D (2011) Occurrence of multiclass UV filters in treated sewage sludge from wastewater treatment plants. Chemosphere 84(8) 1158-1165... 

Bennat, C. and Miiller-Goymann, C.C. (2000) Skin penetration and stabilizationof formulations containing microfine titanium dioxide as physical UV filter. International Journal of Cosmetic Science, 22 (4), 271-283. 

In this chapter, among the large variety of compounds, we include some of the emerging contaminants most commonly found in sewage sludge pharmaceutical compounds, estrogens, illicit drugs, UV filters (sunscreens), BFRs, and PFCs. 

UV filters enter the aquatic environment directly as a result of recreational activities when they are washed off from the skin, or indirectly through wastewater resulting from the use of personal care products, washing clothes, and industrial discharges. Residues of more polar organic UV filters have been found in all kinds... 

In the UV filter analyses, clear extracts were obtained which did not need any further time- and labor-consuming cleanup when using PLE with in-cell purification. In contrast, a thorough purification procedure was required for the cleanup of the extracts obtained by solid-liquid extraction. Columns packed with silica gel (previously activated) in hexane having Na2S04 at the top of the column were employed for the purification of the extracts. The two first fractions obtained with 20 mL of hexane and 20 mL of hexane/diethyl ether (9/1, v/v) were discarded and 4-MBC, EHMC, and OC were collected with 50 mL of hexane/diethyl ether (9/1, v/v). OT was recovered with 70 mL of hexane/diethyl ether (3/2, v/v). 

GC-MS operated in electron impact (El) mode was only sporadically used for the determination of some UV filters such as 4-MBC, EHMC, and OC. Separation was achieved on a 60 m x 0.25 mm i.d. DB-5 column, with 0.25-pm film thickness. For quantification of the compounds, data acquisition was performed in selected ion monitoring (SIM) mode recording three characteristic ions per compound. GC-MS allowed the differentiation between the two isomers (cis/trans) for 4-MBC and EHMC. 

LC-MS-MS was also the method of choice for the analysis of UV filters in solid matrices. Both LC and UPLC have been applied in three out of the four methods available for the determination of UV filters in sludge. Separation was performed on C8 and C18 LC-chromatographic columns (Zorbax, Eclipse, Vydac, and Purosphere) using binary gradient elution of mobile phases consisting of water/ methanol or water/acetonitrile. MS-MS detection was performed in SRM with ESI and atmospheric pressure photoionization (APPI) in both positive and negative modes. For each compound, two characteristics transitions were monitored. In addition to MS and MS-MS, diode array detection (DAD) was occasionally applied to the determination of OT. Spectra were recorded between 240 and 360 nm and discrete channels at 310 nm. 

Matrix effects were evaluated by Gago-Ferrero et al. [23]. Both signal suppression and signal enhancement were observed. The extent of these effects was found to be fairly dependent on the UV filter. Thus, quantification should be performed by standard addition or internal standard calibration. Since standard addition is a high time-consuming procedure, internal standard calibration with appropriate isotopi-cally labeled compounds is the best option. 

To date literature on UV filters levels in sewage sludge is very scarce, and only results relative to some compounds are available. To the author s knowledge, there are only four studies [20-23] on the occurrence of UV filters in sewage sludge. 

The concentration levels observed in sewage sludge show that UV filters originate mainly from private households, but besides this, surface runoff and industrial discharges may be considered as additional sources. This indicates that in addition to sunscreens, cosmetics and other personal products, UV filters from plastics, textiles, and other materials can be released to the environment by either volatilization or leaching. 

UV Filters Biodegradation by Fungi, Metabolites Identification and Biological Activity Assessment... 

Keywords Degradation, Fungi, Biological activity, HPLC-MS/MS analysis, Metabolites, UV filters... 

UV filters are currently considered as emerging environmental contaminants of increasing concern since most of the commonly used are known to cause endocrine disrupting effects in both aquatic and terrestrial organisms as well as in human skin cells [4]. These compounds bioaccumulate in fish at similar levels to polychlorinated biphenyls (PCBs) and DDT [5, 6]. 

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