Abstract  The toxicity of tridecafluorohexylethyl methacrylate (6:2 FTMAC), an acrylic monomer used in producing polymeric substances, was evaluated. 6:2 FTMAC has low acute oral and dermal toxicity (LD50>5000 mg/kg), was not a skin or eye irritant, and did not demonstrate skin sensitization potential in a local lymph node assay (LLNA). 6:2 FTMAC was not mutagenic in the bacterial reverse mutation (Ames) test or in the mouse lymphoma assay. 6:2 FTMAC induced structural aberrations in human peripheral blood lymphocytes in vitro in the absence of metabolic activation but not in the presence of S9 metabolic activation. No numerical aberrations were detected under any testing condition. Also, no increase occurred in structural or numerical chromosomal aberrations in an in vivo mouse micronucleus assay in 6:2 FTMAC treated animals compared to controls. 6:2 FTMAC was administered at 0, 100, 500 and 1000 mg/kg/day via gavage to male and female SD rats for 14 days. No test substance-related effects on mortality, clinical signs, body weights, nutritional parameters, or clinical pathology were observed at any dose. Test substance-related increases in liver weights in males and females at all dose levels and thyroid and kidney weights in 500 and 1000 mg/kg/day males were noted. While there was no histopathological correlate for thyroid and kidney weight changes, minimal hypertrophy was noted in liver in males and females at 1000 mg/kg/day group. The changes noted in teeth (altered mineralization; retention of basophilic material) and femur (increased mineralization) in all treated groups were not associated with clinical signs or microscopic changes and were likely related to free fluoride formed from 6:2 FTMAC metabolism. Plasma (3-4-fold) and urine (30-50-fold) fluoride was higher in treated groups versus controls. Therefore, the changes noted in organ weights, teeth, femur, plasma or urine were not considered adverse. In the repeated dose toxicity study, the no-observed-adverse-effect-level (NOAEL) was 1000 mg/kg/day. Based on mean measured concentrations, the 96-h LC50 in fathead minnow was >14.5 mg/L and the 72-h EC50 in Pseudokirchneriella subcapitata was >24.6 mg/L, while the 48-h EC50 in Daphnia magna, based on nominal concentrations, was >120 mg/L. Overall, 6:2 FTMAC is considered to have low toxicity potential based on these studies.

Abstract  The contamination levels and patterns of perfluoroalkyl acids (PFAAs) and their precursors in indoor air of children's bedrooms in Finland, Northern Europe, were investigated. Our study is among the most comprehensive indoor air monitoring studies (n = 57) and to our knowledge the first one to analyse air in children's bedrooms for PFASs (17 PFAAs and 9 precursors, including two acrylates, 6:2 FTAC and 6:2 FTMAC). The most frequently detected compound was 8:2 fluorotelomer alcohol (8:2 FTOH) with the highest median concentration (3570 pg/m(3)). FTOH concentrations were generally similar to previous studies, indicating that in 2014/2015 the impact of the industrial transition had been minor on FTOH levels in indoor air. However, in contrast to earlier studies (with one exception), median concentrations of 6:2 FTOH were higher than 10:2 FTOH. The C8 PFAAs are still the most abundant acids, even though they have now been phased out by major manufacturers. The mean concentrations of FOSE/As, especially MeFOSE (89.9 pg/m(3)), were at least an order of magnitude lower compared to previous studies. Collectively the comparison of FTOHs, PFAAs and FOSE/FOSAs with previous studies indicates that indoor air levels of PFASs display a time lag to changes in production of several years. This is the first indoor air study investigating 6:2 FTMAC, which was frequently detected (58%) and displayed some of the highest maximum concentrations (13 000 pg/m(3)). There were several statistically significant correlations between particular house and room characteristics and PFAS concentrations, most interestingly higher EtFOSE air concentrations in rooms with plastic floors compared to wood or laminate.

Abstract  The functionalization and application of nano-objects generated using a polymerization induced self-assembly (PISA) procedure is becoming a focus in recent years. In this contribution, using ethanol as solvent, poly(oligo(ethylene oxide) methyl ether methacrylate) (POEOMA) as macro-initiator/stabilizer, and 2-(perfluorohexyl)ethyl methacrylate (PFHEMA) and glycidyl methacrylate (GMA) as comonomers, the initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP)-based PISA is realized. The lower GMA content system tends to form spheres with large diameters and heavy contrast, while the lower PFHEMA content system tends to form the spheres or short worms with small diameters. However, the system with further increased GMA content results in the failed ICAR ATRP PISA procedure with the formation of precipitates by the cross-linking reaction between pendant epoxy groups. Furthermore, using the efficient reaction between the epoxy group on GMA and thiol group on mercapto-succinic acid agent, the carboxyl groups can be introduced into the inner cavity of the nano-objects and used for incorporation with the Fe2+ and Fe3+ ions, and the organic-inorganic nanoparticles Fe3 O4 @POEOMA are finally prepared in the presence of a reductant.