Health & Environmental Research Online (HERO)


FtOH 6:2 (647-42-7)


93 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Synthesis of fluorinated polycarbonate-based polyurethane acrylate for UV-curable coatings

Authors: Liu, J; Wang, B; Yuan, Yan; Liu, Ren; Li, Z; Liu, X (2017) HERO ID: 3859231

[Less] Fluorinated polycarbonate-based UV-curable polyurethane acrylate (F-PCUA) was synthesized by incorporating . . . [More] Fluorinated polycarbonate-based UV-curable polyurethane acrylate (F-PCUA) was synthesized by incorporating 1H, 1H, 2H, 2H-Perfluoro-1-octanol to the end of polycarbonate-based PUA chains. The structure of F-PCUA was determined by H-1-NMR, F-19-NMR, and FTIR analyses. The physical, surface, and thermal properties of F-PCUA were also examined. The F-PCUA was used as a hydrophobic additive in PUA coatings, and the water and oil wettability of the UV-cured film was investigated by contact angle measurements. The results showed that the coating system had great hydrophobicity. Furthermore, X-ray photoelectron spectroscopy research confirmed that a hydrophobic fluorine-enriched surface was obtained in the coating system. Moreover, the mechanical and chemical properties of the hydrophobic coatings did not show deterioration with the introduction of elemental F.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Fluorinated Candle Soot as the Lubricant Additive of Perfluoropolyether

Authors: Huang, G; Yu, Q; Ma, Z; Cai, M; Zhou, F; Liu, W (2017) Tribology Letters 65. HERO ID: 3857371

[Less] In order to improve the tribological properties of perfluoropolyethers (PFPE), fluorinated candle soot . . . [More] In order to improve the tribological properties of perfluoropolyethers (PFPE), fluorinated candle soot is adopted as the lubricant additive because of their special onion-like structure. The candle soot particles (CSP) are modified by 1H, 1H, 2H, 2H-perfluorooctanol (CSP-PFHE nanoparticles), and after the fluorination, they exhibit good dispersivity in PFPE. The mixtures composed of CSP-PFHE nanoparticles and PFPE possess better tribological performance than neat PFPE under different test conditions including variable temperature, the irradiation of atomic oxygen and extreme pressure. The reason can be attributed to that the graphene layers are exfoliated from the surfaces of nanoparticles and adhere onto the steel surfaces to form the tribofilm, which can protect the sliding pairs surfaces from friction and severe wear. Meanwhile, the redundant nanoparticles act as the rolling bearing between the sliding surfaces to decrease the wear and some are packed into the corrosion pits generated by PFPE to prevent further erosion in the process of friction. At the end, the lubricating mechanism of CSP-PFHE nanoparticles as additives of PFPE is proposed based on the test results of scanning electron microscope, contact electrical resistance and X-ray photoelectron spectroscopy.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Aerobic biodegradation of 2 fluorotelomer sulfonamide-based aqueous film-forming foam components produces perfluoroalkyl carboxylates

Authors: D'Agostino, LA; Mabury, SA (2017) Environmental Toxicology and Chemistry 36:2012-2021. HERO ID: 3859275

[Less] The biodegradation of 2 common fluorotelomer surfactants used in aqueous film forming foams (AFFFs), . . . [More] The biodegradation of 2 common fluorotelomer surfactants used in aqueous film forming foams (AFFFs), 6:2 fluorotelomer sulfonamide alkylamine (FTAA) and 6:2 fluorotelomer sulfonamide alkylbetaine (FTAB), was investigated over 109 d with aerobic wastewater-treatment plant (WWTP) sludge. Results show that biodegradation of 6:2 FTAA and 6:2 FTAB produces 6:2 fluorotelomer alcohol (FTOH), 6:2 fluorotelomer carboxylic acid (FTCA), 6:2 fluorotelomer unsaturated carboxylic acid (FTUCA), 5:3 FTCA, and short-chain perfluoroalkyl carboxylates (PFCAs). Additional degradation products included 6:2 fluorotelomer sulfonamide (FTSAm), which was a major degradation product in the presence of either active or sterilized sludge, whereas 6:2 fluorotelomer sulfonate (FTSA) production was measured with sterilized sludge only. Six additional degradation products were tentatively identified by quadrupole time-of-flight mass spectrometry (qTOF-MS) and attributed to N-dealkylation and oxidation of 6:2 FTAA. Environ Toxicol Chem 2017;9999:1-10. © 2017 SETAC.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Fluorophilicity and lipophilicity of fluorinated rhodamines determined by their partition coefficients in biphasic solvent systems

Authors: Jbeily, M; Kressler, J (2017) HERO ID: 3859230

[Less] The 1-octanol/water (In P-o/w) and perfluoro(methylcyclohexane)/toluene (In P-PFMC/Tol) partition coefficients . . . [More] The 1-octanol/water (In P-o/w) and perfluoro(methylcyclohexane)/toluene (In P-PFMC/Tol) partition coefficients were measured for four fluorinated rhodamine-based fluorescence dyes (F-rhodamines) functionalized with F-ponytails of various lengths CnH2n-CmF2m+1 (n = 1,2 and m = 3,7,8,10) at both amine groups. Here, the In P-o/w accounts usually for the lipophilic-hydrophilic ratio in ageous (biological) media whereas the In P-PFMC/Tol is a standard value for the description of the fluorophilic-lipophilic ratio. Both partition coefficients correlated with the CmF2m+1/CnH2n ratio, but not directly with the length of the F-ponytails. The ability of the F-rhodamines to incorporate into the hydrophobic part of the bilayer of giant unilamellar vesicles (GUVs) of 1,2-dioleoyl-sn-glycero-3-phosphbcholine (DOPC) mixed with 1H,1H,2H,2H-perfluoro-1-octanol (F6H2OH) using confocal laser scanning microscopy was tested and the partitioning of the F-rhodamines into the mixed GUVs could not be explained exclusively using the two In P values mentioned above. Two other partition coefficients between F6H2OH/W (In P-F6H2OH/W) and perfluoro-n-octane/n-octane (In PF-oct/oct) were measured. The In PF-oct/oct correlated in a comparable way with the In P-PFMC/Tol, whereas In P-F6H2OH/W accounting for the fluorophilic-hydrophilic ratio correlated with the length of the F-ponytails and additionally clarified the different staining abilities of the synthesized F-rhodamines in the mixed GUVs. (C) 2016 Elsevier B.V. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Impact of 6:2 fluorotelomer alcohol aerobic biotransformation on a sediment microbial community

Authors: Zhang, S; Merino, N; Wang, N; Ruan, T; Lu, X (2017) Science of the Total Environment 575:1361-1368. HERO ID: 3857384

[Less] Sediment microbial communities are responsible for many chemical biotransformation processes in the . . . [More] Sediment microbial communities are responsible for many chemical biotransformation processes in the aquatic environment and play a critical role in various ecosystems and biogeochemical cycling. However, the impact of polyfluoroalkyl substances on sediment microbial communities remains unclear. These substances are increasingly being used in consumer and industrial products to replace environmentally persistent perfluoroalkyl substances. In this study, we investigated the effects of low (5mg/L) and high (15mg/L) doses of 6:2 fluorotelomer alcohol [6:2 FTOH, F(CF2)6CH2CH2OH] on the structure of a sediment microbial community. 6:2 FTOH biotransformation was rapid in the sediment mixture with a half-life <3days, regardless of the initial doses. After 28days, major products produced in the high dose condition included 28mol% 5:2 sFTOH [F(CF2)5CH(OH)CH3], 9.6mol% 5:3 Acid [F(CF2)5CH2CH2COOH] and 11mol% PFHxA [F(CF2)5COOH], while 73mol% 5:2 sFTOH, 23mol% 5:3 Acid and 26mol% PFHxA were observed in the low dose condition. In the original (control) sediment without 6:2 FTOH dosing, Proteobacteria was the predominant microorganism (18%), followed by Chloroflexi (14%), Verrucomicrobia (13%), Firmicutes (3.4%), Bacterioidetes (2.4%), Actinobacteria (1.7%) and Planctomycetes (1.3%). The presence of 6:2 FTOH and the accumulation of transient transformation products in the sediment exerted selection pressure on the microbial taxonomic distribution and diversity. Our observations indicate that potential 6:2 FTOH degraders and tolerant strains, such as Dokdonella spp., Thauera spp., Albidovulum spp. and Caldanaerovirga spp., existed in the sediment mixture and began to dominate over time. This suggests that these genera might have higher tolerance towards elevated 6:2 FTOH and its transformation products. These findings on the characterization of sediment microbial community stability and dynamics will help predict changes in response to perfluoroalkyl and polyfluoroalkyl substances and also help identify robust microbial strains to degrade polyfluoroalkyl substances in the environment.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Perfluoroalkyl acids and their precursors in indoor air sampled in children's bedrooms

Authors: Winkens, K; Koponen, J; Schuster, J; Shoeib, M; Vestergren, R; Berger, U; Karvonen, AM; Pekkanen, J; Kiviranta, H; Cousins, IT (2017) Environmental Pollution 222:423-432. HERO ID: 3857420

[Less] The contamination levels and patterns of perfluoroalkyl acids (PFAAs) and their precursors in indoor . . . [More] 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.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

HPLC-MS/MS methods for the determination of 52 perfluoroalkyl and polyfluoroalkyl substances in aqueous samples

Authors: Gremmel, C; Frömel, T; Knepper, TP (2017) Analytical and Bioanalytical Chemistry 409:1643-1655. HERO ID: 3859232

[Less] Two quantitative methods using high-performance liquid chromatography (HPLC) combined with triple quadrupole . . . [More] Two quantitative methods using high-performance liquid chromatography (HPLC) combined with triple quadrupole tandem mass spectrometry (MS/MS) were developed to determine perfluoroalkyl and polyfluoroalkyl substances (PFASs) in aqueous samples. The first HPLC-MS/MS method was applied to 47 PFASs of 12 different substance classes with acidic characteristics such as perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs), as well as precursor substances and biotransformation intermediates (e.g., unsaturated fluorotelomer carboxylic acids). In addition, 25 (13)C-, (18)O-, and (2)H-labeled PFASs were used as internal standards in this method. The second HPLC-MS/MS method was applied to fluorotelomer alcohols (FTOHs) and perfluorooctane sulfonamidoethanols as these compounds have physicochemical properties different from those of the previous ones. Accuracy between 82% and 110% and a standard deviation in the range from 2% to 22% depending on the substances were determined during the evaluation of repeatability and precision. The method quantification limit after solid-phase extraction ranged from 0.3 to 199 ng/L depending on the analyte and matrix. The HPLC-MS/MS methods developed were suitable for the determination of PFASs in aqueous samples (e.g., wastewater treatment plant effluents or influents after solid-phase extraction). These methods will be helpful in monitoring campaigns to evaluate the relevance of precursor substances as indirect sources of perfluorinated substances in the environment. In one exemplary application in an industrial wastewater treatment plant, FTOHs were found to be the major substance class in the influent; in particular, 6:2-FTOH was the predominant compound in the industrial samples and accounted for 74% of the total PFAS concentration. The increase in the concentration of the transformation products of FTOHs in the corresponding effluent, such as fluorotelomer carboxylic acids, unsaturated fluorotelomer carboxylic acids, n:3 polyfluorinated saturated carboxylic acids (n indicates the number of nonfluorinated carbon atoms), and PFCAs, indicated biotransformation of FTOHs or their derivatives during wastewater treatment. However, only 33 mol% of the total amount of PFASs present in the influent was quantified in the corresponding effluent. Graphical abstract Method development of an HPLC-MS/MS multi-method for the determination of PFASs in aqueos samples.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

6:2 fluorotelomer carboxylic acid (6:2 FTCA) exposure induces developmental toxicity and inhibits the formation of erythrocytes during zebrafish embryogenesis

Authors: Shi, G; Cui, Q; Pan, Y; Sheng, N; Guo, Y; Dai, J (2017) Aquatic Toxicology 190:53-61. HERO ID: 3859274

[Less] Saturated fluorotelomer carboxylic acids (FTCAs) are intermediates in the degradation of fluorotelomer . . . [More] Saturated fluorotelomer carboxylic acids (FTCAs) are intermediates in the degradation of fluorotelomer alcohols (FTOHs) to perfluorinated carboxylic acids (PFCAs). Recent studies have detected FTCAs in precipitation, surface waters, and wildlife, but few studies have focused on their toxicity. In this study, zebrafish embryos were exposed to different concentrations of 6:2 FTCA (0, 4, 8, and 12mg/L) from 6 to 120h post-fertilization (hpf) to investigate its developmental toxicity. Results showed that 6:2 FTCA exposure decreased the hatching and survival percentages, reduced the heart rate, and increased the malformation of zebrafish embryos. The median lethal concentration of 6:2 FTCA was 7.33mg/L at 120 hpf, which was lower than that of perfluorooctanoic acid (PFOA), thus indicating higher toxicity for zebrafish. The most common developmental malformation was pericardial edema, which appeared in the 8 and 12mg/L 6:2 FTCA-exposed embryos from 60 hpf. Using o-dianisidine staining, we found that the hemoglobin content in embryos was reduced in a concentration-dependent manner after 6:2 FTCA exposure at 72 hpf. Based on quantitative real-time polymerase chain reaction (q-RT-PCR) and whole-mount in situ hybridization, the transcriptional levels of hemoglobin markers (hbae1, hbbe1, and hbae3) were down-regulated at 48 and 72 hpf, even though no observed malformation appeared in zebrafish at 48 hpf. Moreover, 6:2 FTCA exposure decreased the protein level of gata1, a principal early erythrocytic marker, in Tg (gata1:DsRed) transgenic zebrafish at 72 hpf. We analyzed the transcriptional level of other erythrocyte-related genes using q-RT-PCR assay. For heme formation, the transcription of alas2, which encodes the key enzyme for heme biosynthesis, was down-regulated after 6:2 FTCA exposure, whereas the transcription of ho-1, which is related to heme degradation, was up-regulated at 48 and 72 hpf. The transcriptional patterns of gata1 and gata2, which are related to erythroid differentiation, differed. At 48 hpf, the mRNA level of gata2 was significantly increased, whereas that of gata1 exhibited no significant changes in any treatment group. At 72 hpf, the expressions of both were down-regulated in a concentration-dependent manner. Taken together, 6:2 FTCA exposure decreased the erythrocyte number and disrupted erythroid differentiation during zebrafish embryonic development. Our results suggest that 6:2 FTCA can cause developmental toxicity in zebrafish embryos, and that FTCAs exhibit greater toxicity than that of PFCAs.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Preparation and characterization of yellowing resistance and low volume shrinkage of fluorinated polysiloxane urethane acrylate

Authors: Ping, Tuo; Zhou, Y; He, Y; Tang, Y; Yang, J; Akram, MY; Nie, Jun (2016) Progress in Organic Coatings 97:74-81. HERO ID: 3857376

[Less] Fluorinated polysiloxane urethane acrylates were synthesized by 1H,1H,2H,2H-Perfluorooctanol (F13), . . . [More] Fluorinated polysiloxane urethane acrylates were synthesized by 1H,1H,2H,2H-Perfluorooctanol (F13), polysiloxane (PSi), isophorone diisocyanate (IPDI) and 2-hydroxyethyl acrylate (HEA). The molecular structure was characterized by FTIR, GPC, and XPS. The yellowing resistance was measured by sphere Spectrophotometer and ultraviolet-visible spectrophotometer. The volume shrinkage was measured by laser displacement sensor (LDS). The glass-transition temperature (Tg) and storage modulus (E') were measured by dynamic mechanical analysis (DMA). Real time infrared (RTIR) spectroscopy was used to investigate the reaction kinetics of photopolymerization of synthesized fluorinated polysiloxane urethane acrylate (PSi-IPDI-HEA-F13). It was proved that the introduced of 1H,1H,2H,2H-Perfluorooctanol into the system of polysiloxane urethane acrylates (PSi-IPDI-HEA) could increase the yellowing resistance and decrease the volume shrinkage. Thermal stability was reduced by a small amount. (C) 2016 Elsevier B.V. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Multianalyte profiling of per- and polyfluoroalkyl substances (PFASs) in liquid commercial products

Authors: Favreau, P; Poncioni-Rothlisberger, C; Place, BJ; Bouchex-Bellomie, H; Weber, A; Tremp, J; Field, JA; Kohler, M (2016) Chemosphere 171:491-501. HERO ID: 3456986

[Less] The chemical properties of poly- and perfluoroalkyl substances (PFASs) make them widespread for use . . . [More] The chemical properties of poly- and perfluoroalkyl substances (PFASs) make them widespread for use in a number of industrial and commercial products to confer water and oil-repellency characteristics and to reduce surface tension e.g. in aqueous film-forming foams (AFFFs). Some PFASs, especially perfluoroctane sulfonate, and several perfluoroalkyl carboxylic acids, are known to cause significant human and environmental negative impact. Our knowledge on the content of PFASs in products remains scarce due to limited information available, thus impeding any precise assessment of human exposure and environmental release upon use. This study aimed at analyzing a wide variety of liquid products (n = 194) likely to contain PFASs, including impregnating agents, lubricants, cleansers, polishes, AFFFs and other industrial products. By means of LC- and GC-MS/MS analytical techniques, 24 PFASs (from 41 targeted PFASs) were detected and quantified in 55% of samples. PFAS quantification and profiling was found to be consumer product specific. PFASs were mostly detected in AFFF (90%) and impregnating agents (60%) with mainly ionic and neutral species, respectively. In particular, the fluorotelomer alcohols 6:2, 8:2 and 10:2 FTOHs were detected in 40-50% of impregnating agents. Further investigation by Fast Atom Bombardment Mass Spectrometry (FAB-MS) on a set of AFFF samples allowed the characterization of 8 different PFAS classes as major components in these formulations. Results demonstrated that numerous and diversified PFAS are currently used in specific commercial products, implying significant human exposure and environmental release that necessitate further research concerning their toxicological impact.