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1.
ECLIPSE cigarettes utilize a special form of continuous glass filament (CGF) as an insulator around the carbon heat source. The average numbers of CGFs on the external barrel and cigarette filter end were determined subsequent to manufacture, subsequent to real-world consumer handling and subsequent to simulated consumer handling. The following were not statistically significantly different: the average number of CGFs on the external barrel of cigarettes retrieved from the test market compared to the average external barrel counts from cigarettes subsequent to manufacture or when subjected to simulated consumer handling, and the average number of CGFs on the external barrel of cigarettes subsequent to manufacture compared to the average external barrel counts from cigarettes subjected to simulated consumer handling. The average number of CGFs on the filter end of cigarettes retrieved from the test market was statistically significantly higher than average cigarette filter end counts from cigarettes subsequent to manufacture. The average number of CGFs on the cigarette filter end of cigarettes retrieved from the test market was statistically significantly lower than average cigarette filter end counts from cigarettes subjected to simulated consumer handling. Overall, results from this study suggest that consumer handling does increase the average numbers of CGFs on the external surfaces of the cigarette. Further, the results of this study demonstrate that for the purpose of CGF quantification, the simulated consumer handling protocol used in this study (i.e., based on laboratory measurements of forces) is a reasonably good model for actual consumer handling of cigarettes. Based on the minimal number of CGFs that could be transferred to the smoker and the deposition pattern governed by their physical characteristics, the potential to deposit CGFs from these cigarettes to the lungs of smokers is extremely remote. Therefore, no convincing information exists to suggest that smokers would be exposed to CGFs from any ECLIPSE-related source at a biologically significant level.  相似文献   

2.
This study was designed to determine if the Eclipse prototype 9-014 cigarettes, which use a special form of continuous glass filament (CGF) as an insulator around the carbon heat source, yield CGFs via mainstream smoke. A previously developed method (Higuchi et al., 2000) that employed electrostatic precipitation-with a greater than 99% collection efficiency of mass-was used to capture CGFs transferred to mainstream smoke. The cigarettes were smoked using an exaggerated puffing condition more than twice the Federal Trade Commission (FTC) standard. Prior to smoking, cigarettes were subjected to handling procedures that simulated commercial shipping conditions. Using a modified standard addition method, and utilizing a mixture of water and glycerol as a mock condensate, CGFs were intentionally added to a series of (mock condensate) samples to develop knowledge of CGF recovery efficiency. The linear regression model of the recovered CGFs demonstrated a recovery efficiency of 86%. This efficiency rate was applied to the number of CGFs recovered from samples of smoke condensate and associated background samples. The number of CGFs in smoke condensate collected from the Eclipse 9-014 prototype was approximately 0.32 +/- 0.17 CGFs per cigarette (+/- standard deviation), including the background counts of CGFs, and 0.16 CGFs per cigarette when corrected for background contributions. The number of CGFs found in the smoke condensates for this prototype was statistically (p =.00031) distinguishable from zero and background in these experiments. The low number of CGFs seen in the transfer data from this prototype studied, the unique physical characteristics of the filaments (e.g., controlled physical dimensions), and the absence of biological activity of similar glass filaments/fibers indicate that biologically significant exposure to the Eclipse smoker does not occur.  相似文献   

3.
目的:评价真实世界中妊娠期甲状腺功能亢进(简称"甲亢")患者应用抗甲状腺药物(ATDs)的安全性。方法:收集厦门大学附属中山医院2016年1至2020年12月收治的妊娠期甲亢患者的临床资料,分别根据妊娠期使用ATDs后甲状腺功能(简称"甲功")情况以及妊娠期ATDs暴露情况进行分组,比较各组组内安全性指标的差异。结果:共收集102例孕产妇及其分娩的103例新生儿的资料,按3种不同情形分组并进行安全性评价,结果显示:(1)妊娠期甲亢组的早产发生率比甲功正常组更高(P<0.05);(2)妊娠早期使用甲巯咪唑治疗组(M组)比使用丙硫氧嘧啶治疗组(P组)的新生儿出生缺陷发生率更高(P<0.05);(3)P组中,妊娠中晚期使用丙硫氧嘧啶治疗组(PP组)的肝功能异常发生率高于妊娠中晚期使用甲巯咪唑治疗组(PM组),但两者之间的差异无统计学意义(P>0.05)。以上3组组内之间其余安全性评价指标比较,均无统计学差异(P>0.05)。结论:妊娠期甲亢和ATDs的应用均可能对孕产妇和新生儿的安全性产生影响。因此建议妊娠期甲亢应合理选择ATDs开展个体化治疗,同时注意监测相关实验室指标以及ATDs的不良反应,以保障整个妊娠期治疗的安全性和有效性。  相似文献   

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This assessment focusses on polyethylene glycols (PEGs) and on anionic or nonionic PEG derivatives, which are currently used in cosmetics in Europe. These compounds are used in a great variety of cosmetic applications because of their solubility and viscosity properties, and because of their low toxicity. The PEGs, their ethers, and their fatty acid esters produce little or no ocular or dermal irritation and have extremely low acute and chronic toxicities. They do not readily penetrate intact skin, and in view of the wide use of preparations containing PEG and PEG derivatives, only few case reports on sensitisation reactions have been published, mainly involving patients with exposure to PEGs in medicines or following exposure to injured or chronically inflamed skin. On healthy skin, the sensitising potential of these compounds appears to be negligible. For some representative substances of this class, information was available on reproductive and developmental toxicity, on genotoxicty and carcinogenic properties. Taking into consideration all available information from related compounds, as well as the mode and mechanism of action, no safety concern with regard to these endpoints could be identified. Based on the available data it is therefore concluded that PEGs of a wide molecular weight range (200 to over 10,000), their ethers (laureths. ceteths, ceteareths, steareths, and oleths), and fatty acid esters (laurates, dilaurates, stearates, distearates) are safe for use in cosmetics. Limited data were available for PEG sorbitan/sorbitol fatty acid esters, PEG sorbitan beeswax and PEG soy sterols. Taking into account all the information available for closely related compounds, it can be assumed that these compounds as presently used in cosmetic preparations will not present a risk for human health. PEG castor oils and PEG hydrogenated castor oils have caused anaphylactic reactions when used in intravenous medicinal products. Their topical use in cosmetics is, however, considered safe as they are not expected to be systemically available. As all PEGs and PEG derivatives, they must not be applied to damaged skin. Manufacturers of PEGs and PEG derivatives must continue their efforts to remove impurities and by-products such as ethylene oxide and 1,4-dioxane. Overall, it is concluded, that the PEGs covered in this review are safe for use in cosmetics under the present conditions of intended use.  相似文献   

6.
This publication is the seventh in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers' Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavouring substances under conditions of intended use. In this review, scientific data relevant to the safety evaluation of the allylalkoxybenzene derivatives methyl eugenol and estragole is critically evaluated by the FEMA Expert Panel. The hazard determination uses a mechanism-based approach in which production of the hepatotoxic sulfate conjugate of the 1'-hydroxy metabolite is used to interpret the pathological changes observed in different species of laboratory rodents in chronic and subchronic studies. In the risk evaluation, the effect of dose and metabolic activation on the production of the 1'-hydroxy metabolite in humans and laboratory animals is compared to assess the risk to humans from use of methyl eugenol and estragole as naturally occurring components of a traditional diet and as added flavouring substances. Both the qualitative and quantitative aspects of the molecular disposition of methyl eugenol and estragole and their associated toxicological sequelae have been relatively well defined from mammalian studies. Several studies have clearly established that the profiles of metabolism, metabolic activation, and covalent binding are dose dependent and that the relative importance diminishes markedly at low levels of exposure (i.e. these events are not linear with respect to dose). In particular, rodent studies show that these events are minimal probably in the dose range of 1-10 mg/kg body weight, which is approximately 100-1000 times the anticipated human exposure to these substances. For these reasons it is concluded that present exposure to methyl eugenol and estragole resulting from consumption of food, mainly spices and added as such, does not pose a significant cancer risk. Nevertheless, further studies are needed to define both the nature and implications of the dose-response curve in rats at low levels of exposure to methyl eugenol and estragole.  相似文献   

7.
奥沙利铂的安全性评价   总被引:50,自引:0,他引:50  
奥沙利铂作为第三代铂类抗癌药物,具有特异的细胞毒性。其与5-氟尿嘧啶和亚叶酸联合应用作为一线治疗转移性结肠癌。其抗癌作用明确,具有较顺铂和卡铂疗效好、毒性低等特点,在抗肿瘤治疗上应用比较广泛。奥沙利铂主要不良反应力感觉神经毒性和胃肠道反应等。本文就奥沙利铂临床使用的安全性问题与顺铂、卡铂、伊立替康进行对比评价。  相似文献   

8.
Gamma-cyclodextrin (gamma-CD) is a cyclic alpha-(1,4)-linked oligosaccharide consisting of eight glucose molecules. Like other cyclodextrins, gamma-CD can form inclusion complexes with a variety of organic molecules because the inner side of the torus-like molecule is less polar than the outer side. In foods, gamma-CD may be used as a carrier for flavors, vitamins, polyunsaturated fatty acids, and other ingredients. It also has useful properties as a stabilizer in different food systems. The daily intake from all its intended uses in food at highest feasible concentrations has been estimated at 4.1g/person/day for consumers of gamma-CD containing foods. The present review summarizes the safety data of gamma-CD. The toxicity studies consist of standard genotoxicity tests, subchronic rat studies with oral and intravenous administration of gamma-CD for up to 3 months, a subchronic (3-month) toxicity study in dogs, a (1-year) oral toxicity study in rats, and embryotoxicity/teratogenicity studies in rats and rabbits. In the studies with oral administration, gamma-CD was given at dietary concentrations of up to 20%. All these studies demonstrated that gamma-CD is well tolerated and elicits no toxicological effects. Metabolic studies in rats showed that gamma-CD is rapidly and essentially completely digested by salivary and pancreatic amylase. Therefore, the metabolism of gamma-CD closely resembles that of starch and linear dextrins. A human study with ingestion of single doses of 8 g gamma-CD or 8 g maltodextrin did not reveal a difference in gastrointestinal tolerance of these two products. An interaction of ingested gamma-CD with the absorption of fat-soluble vitamins or other lipophilic nutrients is not to be expected because the formation of inclusion complexes is a reversible process, gamma-CD is readily digested in the small intestine, and studies with beta-CD, a non-digestible cyclodextrin, have shown that the bioavailability of vitamins (A, D, and E) is not impaired. On basis of these studies it is concluded that gamma-CD is generally recognized as safe (GRAS) for its intended uses in food.  相似文献   

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10.
Regulatory agencies have to ensure the end-user safety of botanically derived homeopathic medicines prepared with diluted starting materials derived even from toxic plants. In the case of plant-derived homeopathic products, assessment must consider the particular characteristics of an extract and its component molecules, even if diluted. The identification and quantification of these molecules have a crucial role in risk assessment, as it allows complete toxicological evaluation in a regulatory perspective. Different results can be achieved using different approaches and references supported by the same regulatory framework, as different methods of preparation used, assays and test analysis performed in compliance with different referent pharmacopoeias. All these facts can introduce a bias in the safety assessment and the paradoxical outcome for homeopathic Adonis vernalis underlines the need for caution. The case also demonstrates the relevance of considering the analytical method for assessment of all herbal medicinal products or herbal supplements, with the purpose of finding the total amount of toxicants as a good approach.  相似文献   

11.
The Food and Drug Administration has published a proposal (Chemical Compounds in Food-Producing Animals: Criteria and Procedures for Evaluating Assays for Carcinogenic Residues, Federal Register44, 17070–17114 March 20 1979) to establish procedures and minimum criteria to ensure the absence of cancer-causing residues in edible products of food-producing animals to which drugs, food additives, or color additives have been administered. Section III of the proposed rule (termed the Sensitivity of the Method Document or SOM) would require that metabolism and comparative metabolism studies be conducted in target (food-producing) and test (laboratory) animals, respectively. As a practical matter, current agency policy prescribes that information from such studies would be required whether the compound was considered to be a suspect carcinogen or a noncarcinogen. Metabolism studies to determine what drug-derived residues may be present in the tissues of food-producing animals at a particular withdrawal time as well as comparative metabolism studies to determine the appropriateness of the laboratory animal as a test species, and the relationship of the two studies to each other, are discussed in terms of the procedures used for the human safety assessment of animal drugs.  相似文献   

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14.
目的 评价海藻糖作为药用辅料使用的总体安全性。方法 以SD大鼠为试验对象,测定急性经口毒性;以健康白色家兔为试验对象,测定皮肤、眼刺激性;以豚鼠为试验对象,测定皮肤变态反应(致敏)性;以SD大鼠为试验对象,采用肌肉注射的方法进行90d给药试验,测定长期毒性。结果 在本试验条件下,海藻糖对SD大鼠急性经口毒性为实际无毒,对家兔皮肤、眼睛无刺激性,对豚鼠皮肤的致敏强度为弱致敏物,SD大鼠连续90d肌肉注射给药试验未观察到海藻糖明显的毒性反应,其无毒作用剂量>200 mg/kg。结论 海藻糖作为药用辅料,安全性良好。  相似文献   

15.
This article presents a quantitative risk assessment for the theoretical lifetime cancer risk from the manufacture and use of relatively durable synthetic glass fibers. More specifically, we estimate levels of exposure to respirable fibers or fiberlike structures of E-glass and C-glass that, assuming a working lifetime exposure, pose a theoretical lifetime cancer risk of not more than 1 per 100,000. For comparability with other risk assessments we define these levels as nonsignificant exposures. Nonsignificant exposure levels are estimated from (a) the Institute of Occupational Medicine (IOM) chronic rat inhalation bioassay of durable E-glass microfibers, and (b) the Research Consulting Company (RCC) chronic inhalation bioassay of durable refractory ceramic fibers (RCF). Best estimates of nonsignificant E-glass exposure exceed 0.05-0.13 fibers (or shards) per cubic centimeter (cm3) when calculated from the multistage nonthreshold model. Best estimates of nonsignificant C-glass exposure exceed 0.27-0.6 fibers/cm3. Estimates of nonsignificant exposure increase markedly for E- and C-glass when non-linear models are applied and rapidly exceed 1 fiber/cm3. Controlling durable fiber exposures to an 8-h time-weighted average of 0.05 fibers/cm3 will assure that the additional theoretical lifetime risk from working lifetime exposures to these durable fibers or shards is kept below the 1 per 100,000 level. Measured airborne exposures to respirable, durable glass fibers (or shards) in glass fiber manufacturing and fabrication operations were compared with the nonsignificant exposure estimates described. Sampling results for B-sized respirable E-glass fibers at facilities that manufacture or fabricate small-diameter continuous-filament products, from those that manufacture respirable E-glass shards from PERG (process to efficiently recycle glass), from milled fiber operations, and from respirable C-glass shards from Flakeglass operations indicate very low median exposures of 0, 0.0002, 0.007, 0.008, and 0.0025 fibers (or shards)/cm3, respectively using the NIOSH 7400 Method ("B" rules). Durable glass fiber exposures for various applications must be well characterized to ensure that they are kept below nonsignificant levels (e.g., 0.05 fibers/cm3) as defined in this risk assessment.  相似文献   

16.
Infertility may affect one in six couples; however, the development of the assisted reproduction technique (ART) created the opportunity for a large proportion of the infertile population to bear children. Pharmacological agents are routinely used in ART, and new ones are introduced regularly, with the aim of retrieving multiple oocytes to increase the prospect of pregnancy. The combinations of drugs that are used have specific adverse effects, but it is mostly the combined action of more than one agent that causes the greatest concern. The matter is complicated by the suspicion that some techniques in ART, for example intracytoplasmic sperm injection for severe male infertility problems (including azoospermia), may also contribute to the increase in adverse effects, especially congenital malformation. Gonadotropin releasing hormone (GnRH) agonists are widely used in controlled ovarian hyperstimulation. It may give rise to a short period of estradiol withdrawal symptoms and it may also lead to luteal phase deficiency. Similarly GnRHa antagonists, which have been recently introduced to control ovarian hyperstimulation, can lead to luteal phase deficiency and may cause some local injection site reactions. The more pure form of gonadotropin leads to less local injection site reactions and their main adverse effects are associated with the consequences of multiple ovulations. It has been proposed that gonadotropins may be a factor in the increasing risk of ovarian cancer and possibly breast cancer, but this has not been substantiated. Prion infection is another potential hazard, although no cases have been reported. Ovarian hyperstimulation syndrome is a well recognised complication of controlled ovarian hyperstimulation in ART. It is usually a result of recruitment of a large number of ovarian follicles. Efforts to minimise the incidence of this syndrome and its severity are now well developed. Congenital malformations are another possible adverse effect of fertility drugs, but it is more probable that the increase in congenital abnormality that is reported in ART is because of the population studied, i.e. patients already at high risk of congenital malformation, rather than the fertility drugs used or the technique employed. High order multiple pregnancy and its sequela is a well established complication of controlled ovarian hyperstimulation. This could be a result of multiple ovulations or more than one embryo replacement. Reducing the number of embryos transferred can reduce this more serious adverse effect for expectant mothers and for children conceived from ART.  相似文献   

17.
Acetolactate synthase (ALS) enzymes have been isolated from numerous organisms including soybeans (Glycine max; GM-ALS) and catalyze the first common step in biosynthesis of branched chain amino acids. Expression of an ALS protein (GM-HRA) with two amino acid changes relative to native GM-ALS protein in genetically modified soybeans confers tolerance to herbicidal active ingredients and can be used as a selectable transformation marker. The safety assessment of the GM-HRA protein is discussed. Bioinformatics comparison of the amino acid sequence did not identify similarities to known allergenic or toxic proteins. In vitro studies demonstrated rapid degradation in simulated gastric fluid (<30 s) and intestinal fluid (<1 min). The enzymatic activity was completely inactivated at 50 °C for 15 min demonstrating heat lability. The protein expressed in planta is not glycosylated and genetically modified soybeans expressing the GM-HRA protein produced similar protein/allergen profiles as its non-transgenic parental isoline. No adverse effects were observed in mice following acute oral exposure at a dose of at least 436 mg/kg of body weight or in a 28-day repeated dose dietary toxicity study at doses up to 1247 mg/kg of body weight/day. The results demonstrate GM-HRA protein safety when used in agricultural biotechnology.  相似文献   

18.
Acetolactate synthase (ALS) enzymes have been isolated from numerous organisms including soybeans (Glycine max; GM-ALS) and catalyze the first common step in biosynthesis of branched chain amino acids. Expression of an ALS protein (GM-HRA) with two amino acid changes relative to native GM-ALS protein in genetically modified soybeans confers tolerance to herbicidal active ingredients and can be used as a selectable transformation marker. The safety assessment of the GM-HRA protein is discussed. Bioinformatics comparison of the amino acid sequence did not identify similarities to known allergenic or toxic proteins. In vitro studies demonstrated rapid degradation in simulated gastric fluid (<30 s) and intestinal fluid (<1 min). The enzymatic activity was completely inactivated at 50 °C for 15 min demonstrating heat lability. The protein expressed in planta is not glycosylated and genetically modified soybeans expressing the GM-HRA protein produced similar protein/allergen profiles as its non-transgenic parental isoline. No adverse effects were observed in mice following acute oral exposure at a dose of at least 436 mg/kg of body weight or in a 28-day repeated dose dietary toxicity study at doses up to 1247 mg/kg of body weight/day. The results demonstrate GM-HRA protein safety when used in agricultural biotechnology.  相似文献   

19.
Zinc oxide nanoparticles (ZnO NPs) are commonly used as UV filters in commercial sunscreen products. Their penetration into the skin is intensively discussed in the literature. In the present in vivo study, penetration of ZnO NPs (30 nm in size) into human skin was investigated by multiphoton tomography. Based on the non-linear effects of a second harmonic generation and hyper-Rayleigh scattering, the distribution of ZnO NPs in the horny layers of the epidermis, as well as the furrows, wrinkles and orifice of the hair follicles was analyzed. This method permitted distinguishing between the particulate and dissolved forms of Zn. A detection limit of 0.08 fg/μm(3) was estimated. Taking advantage of this sensitivity, it was clearly shown that ZnO NPs penetrate only into the outermost layers of stratum corneum, furrows and into the orifices of the hair follicles and do not reach the viable epidermis.  相似文献   

20.
It is the experience of dermatologists worldwide that a significant proportion of their patient population has underlying psychological components to their dermatologic complaints. Since these patients are often reluctant to see a mental health professional, the effective management of the underlying psychopathology may require the use of psychotropic medications by the dermatologists. This paper aims to update dermatologists on recent safety information on some of the most commonly prescribed psychotropic medications in psychodermatology. In the process it will also address the implications of these recent safety updates for prescribing clinicians.  相似文献   

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