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"The review focused on the types of chemicals found in nail products, the potential adverse health effects associated with exposure to nail-product chemicals, evidence of chemical exposures in nail salon workers, and evidence supporting actions to reduce chemical exposures in nail salons. Many different types of products are used when providing nail specialty services. These products contain a large variety of chemical ingredients. Many nail-product ingredient s evaporate easily producing vapors and odors that may be inhaled or contact eyes and mucus membranes of nail salon workers and clients. Also, certain procedures during nail care generate dust which may be inhaled. Skin contact is also inherent in the use of nail-care products. Some types of chemicals commonly found in nail salon products are known to be associated with adverse health effects at relatively high exposure levels. Hence, concern has been raised about whether nail salon workers and clients could be at risk for such adverse health effects. The scope of this review is focused on summarizing existing information on the types of chemical ingredients found in nail salon products and in the nail salon indoor environment, the potential hazards of c hemicals in nail salon products , and the effectiveness of interventions to reduce potential hazards. ..."

"Triphenyl phosphate (TPHP) is primarily used as either a flame retardant or plasticizer, and is listed as an ingredient in nail polishes. However, the concentration of TPHP in nail polish and the extent of human exposure following applications have not been previously studied. We measured TPHP in ten different nail polish samples purchased from department stores and pharmacies in 2013–2014. Concentrations up to 1.68% TPHP by weight were detected in eight samples, including two that did not list TPHP as an ingredient. Two cohorts (n = 26 participants) were recruited to assess fingernail painting as a pathway of TPHP exposure. Participants provided urine samples before and after applying one brand of polish containing 0.97% TPHP by weight. Diphenyl phosphate (DPHP), a TPHP metabolite, was then measured in urine samples (n = 411) and found to increase nearly seven-fold 10–14 h after fingernail painting (p < 0.001). To determine relative contributions of inhalation and dermal exposure, ten participants also painted their nails and painted synthetic nails adhered to gloves on two separate occasions, and collected urine for 24 h following applications. Urinary DPHP was significantly diminished when wearing gloves, suggesting that the primary exposure route is dermal. Our results indicate that nail polish may be a significant source of short-term TPHP exposure and a source of chronic exposure for frequent users or those occupationally exposed."

"Case Studies in Nanotoxicology and Particle Toxicology presents a highly-illustrated analysis of the most prominent cases on the adverse effects of nanoparticles and their impact on humans and the environment. This comprehensive reference demonstrates the possible risks imposed by managing and handling nanoparticles, showing the effects of involuntary inhalation or ingestion during their use and after their incineration. Through the use of numerous examples, readers will discover the possible risks and effects of working with nanoparticles, along with best practices to prevent these effects. The text is an essential reference for anyone working in the risk assessment of nanoparticles, including nanosafety professionals, occupational toxicologists, regulatory toxicologists, and clinicians."

"Les pesticides regroupent plus d'un millier de substances actives ayant comme caractéristiques principales de lutter contre les organismes considérés comme nuisibles (animaux, végétaux, champignons) et sont utilisés principalement en milieu agricole. L'exposition aux pesticides peut se produire directement dans le cadre de leur fabrication ou de leurs utilisations professionnelles ou domestiques, mais aussi indirectement par l'air et l'alimentation. La Direction général de la santé a sollicité l'Inserm pour effectuer un bilan de la littérature scientifique permettant de connaître les risques sanitaires associés à l'exposition aux pesticides, en particulier concernant les pathologies cancéreuses, les maladies neurologiques, la fertilité ainsi que les effets sur le développement du fœtus et de l'enfant. Pour répondre à cette demande, l'Inserm s'est appuyé sur un groupe pluridisciplinaire d'experts constitué d'épidémiologistes spécialistes de la santé environnementale ou de la santé au travail et de biologistes spécialistes de la toxicologie cellulaire et moléculaire. Le groupe d'experts a structuré son analyse en trois parties : l'expologie, l'épidémiologie et la toxicologie."

"This review is presented as a common foundation for scientists interested in nanoparticles, their origin, activity, and biological toxicity. It is written with the goal of rationalizing and informing public health concerns related to this sometimes-strange new science of “nano,” while raising awareness of nanomaterials' toxicity among scientists and manufacturers handling them. We show that humans have always been exposed to tiny particles via dust storms, volcanic ash, and other natural processes, and that our bodily systems are well adapted to protect us from these potentially harmful intruders. The reticuloendothelial system, in particular, actively neutralizes and eliminates foreign matter in the body, including viruses and nonbiological particles. Particles originating from human activities have existed for millennia, e.g., smoke from combustion and lint from garments, but the recent development of industry and combustion-based engine transportation has profoundly increased anthropogenic particulate pollution. Significantly, technological advancement has also changed the character of particulate pollution, increasing the proportion of nanometer-sized particles-“nanoparticles”-and expanding the variety of chemical compositions. Recent epidemiological studies have shown a strong correlation between particulate air pollution levels, respiratory and cardiovascular diseases, various cancers, and mortality. Adverse effects of nanoparticles on human health depend on individual factors such as genetics and existing disease, as well as exposure, and nanoparticle chemistry, size, shape, agglomeration state, and electromagnetic properties. Animal and human studies show that inhaled nanoparticles are less efficiently removed than larger particles by the macrophage clearance mechanisms in the lungs, causing lung damage, and that nanoparticles can translocate through the circulatory, lymphatic, and nervous systems to many tissues and organs, including the brain. The key to understanding the toxicity of nanoparticles is that their minute size, smaller than cells and cellular organelles, allows them to penetrate these basic biological structures, disrupting their normal function. Examples of toxic effects include tissue inflammation, and altered cellular redox balance toward oxidation, causing abnormal function or cell death. The manipulation of matter at the scale of atoms, “nanotechnology,” is creating many new materials with characteristics not always easily predicted from current knowledge. Within the nearly limitless diversity of these materials, some happen to be toxic to biological systems, others are relatively benign, while others confer health benefits. Some of these materials have desirable characteristics for industrial applications, as nanostructured materials often exhibit beneficial properties, from UV absorbance in sunscreen to oil-less lubrication of motors. A rational science-based approach is needed to minimize harm caused by these materials, while supporting continued study and appropriate industrial development. As current knowledge of the toxicology of “bulk” materials may not suffice in reliably predicting toxic forms of nanoparticles, ongoing and expanded study of “nanotoxicity” will be necessary. For nanotechnologies with clearly associated health risks, intelligent design of materials and devices is needed to derive the benefits of these new technologies while limiting adverse health impacts. Human exposure to toxic nanoparticles can be reduced through identifying creation-exposure pathways of toxins, a study that may someday soon unravel the mysteries of diseases such as Parkinson's and Alzheimer's. Reduction in fossil fuel combustion would have a large impact on global human exposure to nanoparticles, as would limiting deforestation and desertification. While nanotoxicity is a relatively new concept to science, this review reveals the result of life's long history of evolution in the presence of nanoparticles, and how the human body, in particular, has adapted to defend itself against nanoparticulate intruders."

"So far, little is known about the interaction of nanoparticles with lung cells, the entering of nanoparticles, and their transport through the blood stream to other organs. The entering and localization of different nanoparticles consisting of differing materials and of different charges were studied in human red blood cells. As these cells do not have any phagocytic receptors on their surface, and no actinmyosin system, we chose them as a model for nonphagocytic cells to study how nanoparticles penetrate cell membranes. We combined different microscopic techniques to visualize fine and nanoparticles in red blood cells: (I) fluorescent particles were analyzed by laser scanning microscopy combined with digital image restoration, (II) gold particles were analyzed by conventional transmission electron microscopy and energy filtering transmission electron microscopy, and (III) titanium dioxide particles were analyzed by energy filtering transmission electron microscopy. By using these differing microscopic techniques we were able to visualize and detect particles < or = 0.2 microm and nanoparticles in red blood cells. We found that the surface charge and the material of the particles did not influence their entering. These results suggest that particles may penetrate the red blood cell membrane by a still unknown mechanism different from phagocytosis and endocytosis."

"There are certain concerns regarding the safety for the environment and human health from the use of engineered nanoparticles (ENPs), which leads to unintended exposures, in contrast to the use of ENPs for medical purposes. Animal experiments have shown that investigated ENPs (metallic nanoparticles, quantum dots, carbon nanotubes) can translocate to the brain from different entry points (skin, blood, respiratory pathways). After inhalation or instillation into parts of the respiratory tract a very small fraction of the inhaled or instilled ENPs reaches the blood and subsequently secondary organs, including the central nerve system, at a low translocation rate. Experimental in vivo and in vitro studies have shown that several types of ENPs can have various biological effects in the nervous system. However, the relevance of these data for risk assessment is far from clear. It is, however, unlikely that acute high dose exposures would occur. The risk from such exposures to damage the central nerve system is thus probably even lower. This dossier focuses on the unintended human exposure of ENPs. In particular, possible effects on the functions or processes in the brain are discussed and an attempt to assess the risks is performed. However, the present state of knowledge is unsatisfactory for a proper risk assessment in this area."

"Une première revue de la littérature sur les nanoparticules a incité l'IRSST à publier deux rapports à ce propos au début de 2006, soit sur les risques des nanotechnologies pour la santé et sur divers aspects d'hygiène industrielle les concernant. Or, vu l'évolution rapide des connaissances scientifiques, une mise à jour s'impose déjà. Les chercheurs feront une revue exhaustive de la littérature rendue disponible jusqu'à la fin de 2006 relativement aux risques pour la santé, à l'hygiène industrielle et aux moyens de contrôler l'exposition aux nanoparticules en milieu de travail. En plus de consolider le développement de l'expertise québécoise en ce domaine, cette activité permettra d'intégrer de nouvelles données dans le guide de bonnes pratiques en voie d'élaboration ainsi que d'anticiper les risques reliés à des procédés émergents afin de prévenir l'apparition de maladies professionnelles dans les établissements du Québec qui utilisent les nanotechnologies."