IDENTIFICATION AND USE: Perfluorohexane sulfonate (PFHxS) is a six-carbon compound in the perfluoroalkyl family of chemicals. Perfluorohexane sulfonate was once used in firefighting foam and carpet treatment solutions. It was once widely used as a stain and water repellent but was phased out due to U.S. Environmental Protection Agency regulations. HUMAN EXPOSURE AND TOXICITY: An epidemiological study evaluated the associations between serum levels of PFHxS and diagnosis of attention deficit/hyperactivity disorder (ADHD). In another study, the associations of prenatal serum concentrations (PFHxS) with fetal and postnatal growth in girls was examined. Serum samples were obtained from mothers during pregnancy. PFHxS (median, 1.6 ng/mL) was detected in 100% of samples. On average, girls born to mothers with prenatal concentrations of PFHxS in the upper tertile weighed 108 g less at birth than girls born to mothers with concentrations in the lower tertile in adjusted models. In another study, the association between levels of PFHxS and semen volume, sperm concentration, total sperm count, motility and morphology were assessed. The proportion of morphologically normal cells was 35% lower for the third tertile of PFHxS exposure as compared with the first. In a surveillance study, the serum concentrations of perfluoroalkyl acids (PFAAs) in firefighters was evaluated, and serum concentration of PFHxS was statistically higher in firefighters. Another study reported evidence of a significant association between PFHxS and total cholesterol (TC), low-density lipoprotein cholesterol (LDL), total cholesterol/high density lipoprotein cholesterol ratio (TC/HDL) and non-HDL cholesterol as well as an elevated odds of high cholesterol. In another study, which evaluated the relationship between serum PFCs and thyroid function, increase in natural log-PFHxS was associated with an increase of total T4 by 0.26 ug/mL and total T3 by 4.074 ng/dL in women and a decrease of natural log-free T4 by 0.016 (ng/dL) in men. ANIMAL STUDIES: A subchronic study investigated the mechanism underlying the effect of PFAS surfactants on lipoprotein metabolism. Mice were fed a Western-type diet with PFHxS, (6 mg/kg/day) for 4-6 weeks. PFHxS markedly reduced TG, non-HDL-C, and HDL-C. The decrease in very low-density lipoprotein (VLDL) was caused by enhanced lipoprotein lipase-mediated VLDL-TG clearance and by decreased production of VLDL-TG and VLDL-apolipoprotein B. Reduced HDL production, related to decreased apolipoprotein AI synthesis, resulted in decreased HDL. PFHxS increased liver weight and hepatic TG content. Hepatic gene expression profiling data indicated that these effects were the combined result of peroxisome proliferator-activated receptor alpha and pregnane X receptor activation. Another study showed that neonatal exposure to PFHxS can alter neuroprotein levels, e.g. CaMKII, GAP-43, synaptophysin and tau, which are essential for normal brain development in mice. This was measured for both males and females, in hippocampus and cerebral cortex. The results suggest that PFHxS may act as a developmental neurotoxicant and the effects are similar to that of PFOS and PFOA, but also to other substances such as PCBs, PBDEs and bisphenol A. In another study, in ovo effects of PFHxS exposure (maximum dose = 38,000 ng/g egg) on embryonic death, developmental endpoints, tissue accumulation, mRNA expression in liver and cerebral cortex, and plasma TH levels were evaluated. Pipping success was reduced to 63% at the highest dose of PFHxS; additional effects included decreased tarsus length and embryo mass. Plasma TH levels were reduced in a concentration-dependent manner following PFHxS exposure. A subsequent study evaluated the relationship between PFHxS exposure and TH-dependent neurodevelopmental pathways. PFHxS significantly altered the expression of 11 transcripts at the low dose (890 ng/g) and 101 transcripts at the high dose (38,000 ng/g). Functional enrichment analysis showed that PFHxS affected the genes involved in tissue development and morphology, cellular assembly and organization, and cell-to-cell signaling. In another study, the effects of PFHxS on the neuronal cell death and the underlying mechanisms were examined using PC12 cells as a model of dopaminergic neuron. The treatment with PFHxS reduced cell viability in a dose-dependent manner. PFHxS increased cell apoptosis, increased the activations of ERK1/2, JNK and p38 MAPK with different temporal activations. PFHxS exposure also increased ROS formation.
/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/
/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/
来源:Hazardous Substances Data Bank (HSDB)
毒理性
解毒与急救
/SRP:/ 高级治疗:对于昏迷、严重肺水肿或严重呼吸困难的病人,考虑进行口咽或鼻咽气管插管以控制气道。使用气囊面罩装置的正压通气技术可能有益。考虑使用药物治疗肺水肿……。对于严重的支气管痉挛,考虑给予β激动剂,如沙丁胺醇……。监测心率和必要时治疗心律失常……。开始静脉输注D5W TKO /SRP: "保持开放",最小流量/。如果出现低血容量的迹象,使用0.9%生理盐水(NS)或乳酸钠林格氏液(LR)。对于伴有低血容量迹象的低血压,谨慎给予液体。注意液体过载的迹象……。使用地西泮或劳拉西泮治疗癫痫……。使用丙美卡因氢氯化物协助眼部冲洗……。/毒物A和B/
/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W TKO /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/
/EPIDEMIOLOGY STUDIES/ Our limited understanding of how polyfluoroalkyl chemicals (PFCs) may impact on human health suggests the potential for a protective impact on brain health. This study was designed to explore the association between PFCs and cognitive ability in older adults. We assessed the association between four PFCs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA) and perfluorohexane sulfonic acid (PFHxS), and self-reported limitation due to difficulty remembering or periods of confusion using data from participants aged 60-85 years from the 1999-2000 and 2003-2008 National Health and Nutrition Examination Surveys. We also considered whether diabetic status or diabetic medication use modifies this association in light of in vitro evidence that PFCs may act on the same receptors as some diabetic medications. In multivariable adjusted models, point estimates suggest a protective association between PFCs and self-reported cognitive limitation (odds ratio, OR; 95% confidence interval, CI) for a doubling in PFC concentration: PFOS (OR, 0.90; 95% CI, 0.78, 1.03), PFOA (OR, 0.92; 95% CI, 0.78, 1.09), PFNA (OR, 0.91; 95% CI, 0.79, 1.04) and PFHxS (OR, 0.93; 95% CI, 0.82, 1.06). The protective association was concentrated in diabetics, with strong, significant protective associations in non-medicated diabetics. This cross-sectional study suggests that there may be a protective association between exposure to PFCs and cognition in older adults, particularly diabetics.
/MILK/ The widespread presence of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexanesulfonate (PFHxS) in human general populations and their slow elimination profiles have led to renewed interest in understanding the potential human neonatal exposures of perfluoroalkyls (PFAs) from consumption of human milk. The objective of this study was to evaluate the concentrations of PFOS, PFHxS, and PFOA in pooled human milk samples obtained in Sweden between 1972 and 2008 (a period representing the most significant period of PFA production) and to see whether the time trend of these analytes parallels that indicated in human serum. Chemical analysis of PFOS, PFHxS, and PFOA was performed on pooled Swedish human milk samples from 1972 to 2008 after methodological refinements. The 20 samples which formed the 2007 pool were also analyzed individually to evaluate sample variations. Analyses were performed by HPLC-MS/MS. Due to the complexities of the human milk matrix and the requirement to accurately quantitate low pg/mL concentrations, meticulous attention must be paid to background contamination if accurate results are to be obtained. PFOS was the predominant analyte present in the pools and all three analytes showed statistically significant increasing trends from 1972 to 2000, with concentrations reaching a plateau in the 1990s. PFOA and PFOS showed statistically significant decreasing trends during 2001-2008. At the end of the study, in 2008, the measured concentrations of PFOS, PFHxS, and PFOA in pooled human milk were 75 pg/mL, 14 pg/mL, and 74 pg/mL, respectively. The temporal concentration trends of PFOS, PFHxS, and PFOA observed in human milk are parallel to those reported in the general population serum concentrations.
/MILK/ The presence of perfluoroalkyl acids (PFAAs) in breast milk has been documented, but their lactational transfer has been rarely studied. Determination of the elimination rates of these chemicals during breastfeeding is important and critical for assessing exposure in mothers and infants. We aimed to investigate the association between breastfeeding and maternal serum concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS). For a subset of the population, for whom we also have their infants' measurements, we investigated associations of breastfeeding with infant serum PFAA concentrations. The present analysis included 633 women from the C8 Science Panel Study who had a child < 3.5 years of age and who provided blood samples and reported detailed information on breastfeeding at the time of survey. PFAA serum concentrations were available for all mothers and 8% (n = 49) of the infants. Maternal and infant serum concentrations were regressed on duration of breastfeeding. Each month of breastfeeding was associated with lower maternal serum concentrations of PFOA (-3%; 95% CI: -5, -2%), PFOS (-3%; 95% CI: -3, -2%), PFNA (-2%; 95% CI: -2, -1%), and PFHxS (-1%; 95% CI: -2, 0%). The infant PFOA and PFOS serum concentrations were 6% (95% CI: 1, 10%) and 4% (95% CI: 1, 7%) higher per month of breastfeeding. Breast milk is the optimal food for infants, but is also a PFAA excretion route for lactating mothers and exposure route for nursing infants.
Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are normally the dominant perfluoroalkyl substances (PFASs) in human serum, but here a Canadian family of seven was identified with particularly high exposure to perfluorohexanesulfonate (PFHxS). Disproportionately high serum PFHxS concentrations (range 27.5-423 ng/mL) and moderately high PFOS (range 15.2-108 ng/mL) and PFOA (range 2.40-9.23 ng/mL) concentrations were detected in the family members, with all three chemicals being highest in the youngest children. We therefore sought to identify the source(s) and pathway(s) of this unusual exposure, and to study the excretion of PFASs for this family. Serum, urine, and stool were sampled from family members, carpet, dust, and air were sampled in the home, and a questionnaire was administered. Over 15 years, the family's household carpets were treated 8 times with Scotchgard formulations. Elevated concentrations of PFHxS were detected in household dust (2780 ng/g dust) and in family room carpet (2880 ng/g carpet), and the primary mode of excretion for the major PFASs was through urine. The high PFHxS and moderately high PFOS concentrations in serum and household samples are consistent with the known PFAS content of certain Scotchgard formulations, and exposure was likely through dust ingestion and/or inhalation.
A total of 100 serum samples from 50 new couples (none of the females in this study has ever been pregnant) in Tianjin, North China, were analyzed for eleven perfluoroalkyl acids (PFAAs) with isomer-specific method. Among all samples, total perfluorooctanesulfonate (PFOS, mean 11.3 ng/mL) was predominant followed by total perfluorooctanoate (PFOA, 2.95 ng/mL), perfluorodecanoate (PFDA, 1.17 ng/mL), perfluorononanoate (PFNA, 0.93 ng/mL) and perfluorohexanesulfonate (PFHxS, 0.67 ng/mL). The mean concentrations of PFOS and PFHxS in males (14.2 and 0.89 ng/mL) were significantly higher (p=0.001) than in females (8.36 and 0.45 ng/mL). No statistical difference between genders was observed for the other PFAAs. This suggests that menstruation is one important elimination pathway for PFOS and PFHxS in females. Linear PFOA was the dominant isomer with mean proportion of 99.7%, suggesting that telomeric PFOA (and its precursors), which contains almost pure linear isomer, might be the dominant exposure source of PFOA in Tianjin. On average, the proportion of linear PFOS (n-PFOS) was 59.2% of PFOS, which was lower than that in technical PFOS products (ca. 70% linear). Except perfluoroisopropyl PFOS, all the other monomethyl branched PFOS isomers were enriched in human serum compared to the commercial products, suggesting the monomethyl branched PFOS precursors were preferentially biotransformed in humans /SRP: or a differential clearance occurred/.
Synthesis of symmetric and dissymetric bisperfluoroalkanesulfonylimides and evaluation of their inhibition on bovine carbonic anhydrase
作者:Zohra Benfodda、Franck Guillen、Hubert Blancou
DOI:10.1002/hc.20452
日期:2008.7
describes a synthesis of symmetric and dissymmetric bis[(perfluoroalkane)-sulfonyl]imides by the reaction of the sodium salt of perfluoroalkanesulfonamide RFSO2NH−Na+ (RF = C4F9, C6F13, C8F17) with hexamethyldisilazane and perfluoroalkanesulfonylfluoride RFSO2F (RF = C4F9, C6F13, C8F17). They are obtained, in two steps, in moderate overall yield. Moreover, this paper provides a study of their inhibition on
The present invention relates to: a resist composition such as a chemically amplified resist composition for providing an excellent pattern profile even at a substrate-side boundary face of resist, in addition to a higher resolution in photolithography for micro-fabrication, and particularly in photolithography adopting, as an exposure source, KrF laser, ArF laser, F
2
laser, ultra-short ultraviolet light, electron beam, X-rays, or the like; and a patterning process utilizing the resist composition. The present invention provides a chemically amplified resist composition comprising one or more kinds of amine compounds or amine oxide compounds (except for those having a nitrogen atom of amine or amine oxide included in a ring structure of an aromatic ring) at least having a carboxyl group and having no hydrogen atoms covalently bonded to a nitrogen atom as a basic center.
POSITIVE RESIST COMPOSITION AND PATTERNING PROCESS
申请人:NISHI Tsunehiro
公开号:US20100062374A1
公开(公告)日:2010-03-11
A positive resist composition comprises (A) a resin component which becomes soluble in an alkaline developer under the action of an acid and (B) an acid generator. The resin (A) is a polymer comprising recurring units containing a non-leaving hydroxyl group represented by formula (1) wherein R
1
is H, methyl or trifluoromethyl, X is a single bond or methylene, m is 1 or 2, and the hydroxyl group attaches to a secondary carbon atom. The composition is improved in resolution when processed by lithography.
NOVEL PHOTOACID GENERATOR, RESIST COMPOSITION, AND PATTERNING PROCESS
申请人:Ohsawa Youichi
公开号:US20090246694A1
公开(公告)日:2009-10-01
Photoacid generators generate sulfonic acids of formula (
1
a) upon exposure to high-energy radiation.
ROC(═O)R
1
—COOCH
2
CF
2
SO
3
−
H
+
(1a)
RO is OH or C
1
-C
20
organoxy, R
1
is a divalent C
1
-C
20
aliphatic group or forms a cyclic structure with RO. The photoacid generators are compatible with resins and can control acid diffusion and are thus suited for use in chemically amplified resist compositions.
POLYMERIZABLE ANION-CONTAINING SULFONIUM SALT AND POLYMER, RESIST COMPOSITION, AND PATTERNING PROCESS
申请人:OHASHI Masaki
公开号:US20100099042A1
公开(公告)日:2010-04-22
A polymerizable anion-containing sulfonium salt having formula (1) is provided wherein R
1
is H, F, methyl or trifluoromethyl, R
2
, R
3
and R
4
are C
1
-C
10
alkyl, alkenyl or oxoalkyl or C
6
-C
18
aryl, aralkyl or aryloxoalkyl, or two of R
2
, R
3
and R
4
may bond together to form a ring with S, A is a C
2
-C
20
hydrocarbon group having cyclic structure, and n is 0 or 1. The sulfonium salt generates a very strong sulfonic acid upon exposure to high-energy radiation. A resist composition comprising a polymer derived from the sulfonium salt is also provided.