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2.
Ann Glob Health ; 89(1): 23, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36969097

RESUMEN

Background: Plastics have conveyed great benefits to humanity and made possible some of the most significant advances of modern civilization in fields as diverse as medicine, electronics, aerospace, construction, food packaging, and sports. It is now clear, however, that plastics are also responsible for significant harms to human health, the economy, and the earth's environment. These harms occur at every stage of the plastic life cycle, from extraction of the coal, oil, and gas that are its main feedstocks through to ultimate disposal into the environment. The extent of these harms not been systematically assessed, their magnitude not fully quantified, and their economic costs not comprehensively counted. Goals: The goals of this Minderoo-Monaco Commission on Plastics and Human Health are to comprehensively examine plastics' impacts across their life cycle on: (1) human health and well-being; (2) the global environment, especially the ocean; (3) the economy; and (4) vulnerable populations-the poor, minorities, and the world's children. On the basis of this examination, the Commission offers science-based recommendations designed to support development of a Global Plastics Treaty, protect human health, and save lives. Report Structure: This Commission report contains seven Sections. Following an Introduction, Section 2 presents a narrative review of the processes involved in plastic production, use, and disposal and notes the hazards to human health and the environment associated with each of these stages. Section 3 describes plastics' impacts on the ocean and notes the potential for plastic in the ocean to enter the marine food web and result in human exposure. Section 4 details plastics' impacts on human health. Section 5 presents a first-order estimate of plastics' health-related economic costs. Section 6 examines the intersection between plastic, social inequity, and environmental injustice. Section 7 presents the Commission's findings and recommendations. Plastics: Plastics are complex, highly heterogeneous, synthetic chemical materials. Over 98% of plastics are produced from fossil carbon- coal, oil and gas. Plastics are comprised of a carbon-based polymer backbone and thousands of additional chemicals that are incorporated into polymers to convey specific properties such as color, flexibility, stability, water repellence, flame retardation, and ultraviolet resistance. Many of these added chemicals are highly toxic. They include carcinogens, neurotoxicants and endocrine disruptors such as phthalates, bisphenols, per- and poly-fluoroalkyl substances (PFAS), brominated flame retardants, and organophosphate flame retardants. They are integral components of plastic and are responsible for many of plastics' harms to human health and the environment.Global plastic production has increased almost exponentially since World War II, and in this time more than 8,300 megatons (Mt) of plastic have been manufactured. Annual production volume has grown from under 2 Mt in 1950 to 460 Mt in 2019, a 230-fold increase, and is on track to triple by 2060. More than half of all plastic ever made has been produced since 2002. Single-use plastics account for 35-40% of current plastic production and represent the most rapidly growing segment of plastic manufacture.Explosive recent growth in plastics production reflects a deliberate pivot by the integrated multinational fossil-carbon corporations that produce coal, oil and gas and that also manufacture plastics. These corporations are reducing their production of fossil fuels and increasing plastics manufacture. The two principal factors responsible for this pivot are decreasing global demand for carbon-based fuels due to increases in 'green' energy, and massive expansion of oil and gas production due to fracking.Plastic manufacture is energy-intensive and contributes significantly to climate change. At present, plastic production is responsible for an estimated 3.7% of global greenhouse gas emissions, more than the contribution of Brazil. This fraction is projected to increase to 4.5% by 2060 if current trends continue unchecked. Plastic Life Cycle: The plastic life cycle has three phases: production, use, and disposal. In production, carbon feedstocks-coal, gas, and oil-are transformed through energy-intensive, catalytic processes into a vast array of products. Plastic use occurs in every aspect of modern life and results in widespread human exposure to the chemicals contained in plastic. Single-use plastics constitute the largest portion of current use, followed by synthetic fibers and construction.Plastic disposal is highly inefficient, with recovery and recycling rates below 10% globally. The result is that an estimated 22 Mt of plastic waste enters the environment each year, much of it single-use plastic and are added to the more than 6 gigatons of plastic waste that have accumulated since 1950. Strategies for disposal of plastic waste include controlled and uncontrolled landfilling, open burning, thermal conversion, and export. Vast quantities of plastic waste are exported each year from high-income to low-income countries, where it accumulates in landfills, pollutes air and water, degrades vital ecosystems, befouls beaches and estuaries, and harms human health-environmental injustice on a global scale. Plastic-laden e-waste is particularly problematic. Environmental Findings: Plastics and plastic-associated chemicals are responsible for widespread pollution. They contaminate aquatic (marine and freshwater), terrestrial, and atmospheric environments globally. The ocean is the ultimate destination for much plastic, and plastics are found throughout the ocean, including coastal regions, the sea surface, the deep sea, and polar sea ice. Many plastics appear to resist breakdown in the ocean and could persist in the global environment for decades. Macro- and micro-plastic particles have been identified in hundreds of marine species in all major taxa, including species consumed by humans. Trophic transfer of microplastic particles and the chemicals within them has been demonstrated. Although microplastic particles themselves (>10 µm) appear not to undergo biomagnification, hydrophobic plastic-associated chemicals bioaccumulate in marine animals and biomagnify in marine food webs. The amounts and fates of smaller microplastic and nanoplastic particles (MNPs <10 µm) in aquatic environments are poorly understood, but the potential for harm is worrying given their mobility in biological systems. Adverse environmental impacts of plastic pollution occur at multiple levels from molecular and biochemical to population and ecosystem. MNP contamination of seafood results in direct, though not well quantified, human exposure to plastics and plastic-associated chemicals. Marine plastic pollution endangers the ocean ecosystems upon which all humanity depends for food, oxygen, livelihood, and well-being. Human Health Findings: Coal miners, oil workers and gas field workers who extract fossil carbon feedstocks for plastic production suffer increased mortality from traumatic injury, coal workers' pneumoconiosis, silicosis, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer. Plastic production workers are at increased risk of leukemia, lymphoma, hepatic angiosarcoma, brain cancer, breast cancer, mesothelioma, neurotoxic injury, and decreased fertility. Workers producing plastic textiles die of bladder cancer, lung cancer, mesothelioma, and interstitial lung disease at increased rates. Plastic recycling workers have increased rates of cardiovascular disease, toxic metal poisoning, neuropathy, and lung cancer. Residents of "fenceline" communities adjacent to plastic production and waste disposal sites experience increased risks of premature birth, low birth weight, asthma, childhood leukemia, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer.During use and also in disposal, plastics release toxic chemicals including additives and residual monomers into the environment and into people. National biomonitoring surveys in the USA document population-wide exposures to these chemicals. Plastic additives disrupt endocrine function and increase risk for premature births, neurodevelopmental disorders, male reproductive birth defects, infertility, obesity, cardiovascular disease, renal disease, and cancers. Chemical-laden MNPs formed through the environmental degradation of plastic waste can enter living organisms, including humans. Emerging, albeit still incomplete evidence indicates that MNPs may cause toxicity due to their physical and toxicological effects as well as by acting as vectors that transport toxic chemicals and bacterial pathogens into tissues and cells.Infants in the womb and young children are two populations at particularly high risk of plastic-related health effects. Because of the exquisite sensitivity of early development to hazardous chemicals and children's unique patterns of exposure, plastic-associated exposures are linked to increased risks of prematurity, stillbirth, low birth weight, birth defects of the reproductive organs, neurodevelopmental impairment, impaired lung growth, and childhood cancer. Early-life exposures to plastic-associated chemicals also increase the risk of multiple non-communicable diseases later in life. Economic Findings: Plastic's harms to human health result in significant economic costs. We estimate that in 2015 the health-related costs of plastic production exceeded $250 billion (2015 Int$) globally, and that in the USA alone the health costs of disease and disability caused by the plastic-associated chemicals PBDE, BPA and DEHP exceeded $920 billion (2015 Int$). Plastic production results in greenhouse gas (GHG) emissions equivalent to 1.96 gigatons of carbon dioxide (CO2e) annually. Using the US Environmental Protection Agency's (EPA) social cost of carbonmetric, we estimate the annual costs of these GHG emissions to be $341 billion (2015 Int$).These costs, large as they are, almost certainly underestimate the full economic losses resulting from plastics' negative impacts on human health and the global environment. All of plastics' economic costs-and also its social costs-are externalized by the petrochemical and plastic manufacturing industry and are borne by citizens, taxpayers, and governments in countries around the world without compensation. Social Justice Findings: The adverse effects of plastics and plastic pollution on human health, the economy and the environment are not evenly distributed. They disproportionately affect poor, disempowered, and marginalized populations such as workers, racial and ethnic minorities, "fenceline" communities, Indigenous groups, women, and children, all of whom had little to do with creating the current plastics crisis and lack the political influence or the resources to address it. Plastics' harmful impacts across its life cycle are most keenly felt in the Global South, in small island states, and in disenfranchised areas in the Global North. Social and environmental justice (SEJ) principles require reversal of these inequitable burdens to ensure that no group bears a disproportionate share of plastics' negative impacts and that those who benefit economically from plastic bear their fair share of its currently externalized costs. Conclusions: It is now clear that current patterns of plastic production, use, and disposal are not sustainable and are responsible for significant harms to human health, the environment, and the economy as well as for deep societal injustices.The main driver of these worsening harms is an almost exponential and still accelerating increase in global plastic production. Plastics' harms are further magnified by low rates of recovery and recycling and by the long persistence of plastic waste in the environment.The thousands of chemicals in plastics-monomers, additives, processing agents, and non-intentionally added substances-include amongst their number known human carcinogens, endocrine disruptors, neurotoxicants, and persistent organic pollutants. These chemicals are responsible for many of plastics' known harms to human and planetary health. The chemicals leach out of plastics, enter the environment, cause pollution, and result in human exposure and disease. All efforts to reduce plastics' hazards must address the hazards of plastic-associated chemicals. Recommendations: To protect human and planetary health, especially the health of vulnerable and at-risk populations, and put the world on track to end plastic pollution by 2040, this Commission supports urgent adoption by the world's nations of a strong and comprehensive Global Plastics Treaty in accord with the mandate set forth in the March 2022 resolution of the United Nations Environment Assembly (UNEA).International measures such as a Global Plastics Treaty are needed to curb plastic production and pollution, because the harms to human health and the environment caused by plastics, plastic-associated chemicals and plastic waste transcend national boundaries, are planetary in their scale, and have disproportionate impacts on the health and well-being of people in the world's poorest nations. Effective implementation of the Global Plastics Treaty will require that international action be coordinated and complemented by interventions at the national, regional, and local levels.This Commission urges that a cap on global plastic production with targets, timetables, and national contributions be a central provision of the Global Plastics Treaty. We recommend inclusion of the following additional provisions:The Treaty needs to extend beyond microplastics and marine litter to include all of the many thousands of chemicals incorporated into plastics.The Treaty needs to include a provision banning or severely restricting manufacture and use of unnecessary, avoidable, and problematic plastic items, especially single-use items such as manufactured plastic microbeads.The Treaty needs to include requirements on extended producer responsibility (EPR) that make fossil carbon producers, plastic producers, and the manufacturers of plastic products legally and financially responsible for the safety and end-of-life management of all the materials they produce and sell.The Treaty needs to mandate reductions in the chemical complexity of plastic products; health-protective standards for plastics and plastic additives; a requirement for use of sustainable non-toxic materials; full disclosure of all components; and traceability of components. International cooperation will be essential to implementing and enforcing these standards.The Treaty needs to include SEJ remedies at each stage of the plastic life cycle designed to fill gaps in community knowledge and advance both distributional and procedural equity.This Commission encourages inclusion in the Global Plastic Treaty of a provision calling for exploration of listing at least some plastic polymers as persistent organic pollutants (POPs) under the Stockholm Convention.This Commission encourages a strong interface between the Global Plastics Treaty and the Basel and London Conventions to enhance management of hazardous plastic waste and slow current massive exports of plastic waste into the world's least-developed countries.This Commission recommends the creation of a Permanent Science Policy Advisory Body to guide the Treaty's implementation. The main priorities of this Body would be to guide Member States and other stakeholders in evaluating which solutions are most effective in reducing plastic consumption, enhancing plastic waste recovery and recycling, and curbing the generation of plastic waste. This Body could also assess trade-offs among these solutions and evaluate safer alternatives to current plastics. It could monitor the transnational export of plastic waste. It could coordinate robust oceanic-, land-, and air-based MNP monitoring programs.This Commission recommends urgent investment by national governments in research into solutions to the global plastic crisis. This research will need to determine which solutions are most effective and cost-effective in the context of particular countries and assess the risks and benefits of proposed solutions. Oceanographic and environmental research is needed to better measure concentrations and impacts of plastics <10 µm and understand their distribution and fate in the global environment. Biomedical research is needed to elucidate the human health impacts of plastics, especially MNPs. Summary: This Commission finds that plastics are both a boon to humanity and a stealth threat to human and planetary health. Plastics convey enormous benefits, but current linear patterns of plastic production, use, and disposal that pay little attention to sustainable design or safe materials and a near absence of recovery, reuse, and recycling are responsible for grave harms to health, widespread environmental damage, great economic costs, and deep societal injustices. These harms are rapidly worsening.While there remain gaps in knowledge about plastics' harms and uncertainties about their full magnitude, the evidence available today demonstrates unequivocally that these impacts are great and that they will increase in severity in the absence of urgent and effective intervention at global scale. Manufacture and use of essential plastics may continue. However, reckless increases in plastic production, and especially increases in the manufacture of an ever-increasing array of unnecessary single-use plastic products, need to be curbed.Global intervention against the plastic crisis is needed now because the costs of failure to act will be immense.


Asunto(s)
Enfermedades Cardiovasculares , Disruptores Endocrinos , Retardadores de Llama , Gases de Efecto Invernadero , Neoplasias Pulmonares , Enfermedad Pulmonar Obstructiva Crónica , Estados Unidos , Niño , Animales , Humanos , Masculino , Femenino , Preescolar , Plásticos/toxicidad , Plásticos/química , Ecosistema , Mónaco , Microplásticos , Contaminantes Orgánicos Persistentes , Disruptores Endocrinos/toxicidad , Carbón Mineral
3.
ACS Appl Mater Interfaces ; 14(48): 54245-54255, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36440705

RESUMEN

Recent developments of highly expandable foaming pre-polymer resins for lithographic additive manufacturing have allowed for the creation of structures larger than a printer's build envelope. To fully utilize the capabilities of this technology, the mechanical properties of these foams must be improved. This manuscript presents one method for strengthening these lightweight polymeric structures via aerosol spray application of a high-strength, low-viscosity photocurable coating. This method is free from the reliance on often complex, large, or bulky on-site equipment ordinarily required by conventional high-strength spray coating. The newly formulated photocurable resin can be applied using an ordinary cordless paint sprayer and cured using sunlight in less than a minute, enabling the rapid production of large, load-bearing structures from a small volume of feedstock and low-cost portable equipment. A comprehensive screening process for resin formulations, detailed mechanical compression and tensile analysis of coated polymer structures, and an applied technical demonstration of the technology are described. The photocurable coating described herein greatly strengthens porous polymeric structures using a method that can be easily implemented.

4.
Macromol Biosci ; 22(12): e2200292, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36122179

RESUMEN

Blood loss causes an estimated 1.9 million deaths per year globally, making new methods to stop bleeding and promote clot formation immediately following injury paramount. The fabrication of functional hemostatic materials has the potential to save countless lives by limiting bleeding and promoting clot formation following an injury. This work describes the melt manufacturing of poly(ε-caprolactone) nanofibers and their chemical functionalization to produce highly scalable materials with enhanced blood clotting properties. The nanofibers are manufactured using a high throughput melt coextrusion method. Once isolated, the nanofibers are functionalized with polymers that promote blood clotting through surface-initiated atom transfer radical polymerization. The functional nanofibers described herein speed up the coagulation cascade and produce more robust blood clots, allowing for the potential use of these functional nonwoven mats as advanced bandages.


Asunto(s)
Hemostáticos , Nanofibras , Trombosis , Humanos , Nanofibras/química , Coagulación Sanguínea , Hemostáticos/química , Vendajes , Hemorragia
5.
Biomacromolecules ; 23(3): 903-912, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35139303

RESUMEN

Prophylactic vaccines capable of preventing human papillomavirus (HPV) infections are still inaccessible to a vast majority of the global population due to their high cost and challenges related to multiple administrations performed in a medical setting. In an effort to improve distribution and administration, we have developed dissolvable microneedles loaded with a thermally stable HPV vaccine candidate consisting of Qß virus-like particles (VLPs) displaying a highly conserved epitope from the L2 protein of HPV (Qß-HPV). Polymeric microneedle delivery of Qß-HPV produces similar amounts of anti-HPV16 L2 IgG antibodies compared to traditional subcutaneous injection while delivering a much smaller amount of intradermal dose. However, a dose sparing effect was found. Furthermore, immunization yielded neutralizing antibody responses in a HPV pseudovirus assay. The vaccine candidate was confirmed to be stable at room temperature after storage for several months, potentially mitigating many of the challenges associated with cold-chain distribution. The ease of self-administration and minimal invasiveness of such microneedle patch vaccines may enable wide-scale distribution of the HPV vaccine and lead to higher patient compliance. The Qß VLP and its delivery technology is a plug-and-play system that could serve as a universal platform with a broad range of applications. Qß VLPs may be stockpiled for conjugation to a wide range of epitopes, which are then packaged and delivered directly to the patient via noninvasive microneedle patches. Such a system paves the way for rapid distribution and self-administration of vaccines.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Vacunas de Partículas Similares a Virus , Animales , Anticuerpos Antivirales , Proteínas de la Cápside , Epítopos , Humanos , Ratones , Ratones Endogámicos BALB C , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico
6.
Nat Nanotechnol ; 15(8): 646-655, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32669664

RESUMEN

The COVID-19 pandemic has infected millions of people with no clear signs of abatement owing to the high prevalence, long incubation period and lack of established treatments or vaccines. Vaccines are the most promising solution to mitigate new viral strains. The genome sequence and protein structure of the 2019-novel coronavirus (nCoV or SARS-CoV-2) were made available in record time, allowing the development of inactivated or attenuated viral vaccines along with subunit vaccines for prophylaxis and treatment. Nanotechnology benefits modern vaccine design since nanomaterials are ideal for antigen delivery, as adjuvants, and as mimics of viral structures. In fact, the first vaccine candidate launched into clinical trials is an mRNA vaccine delivered via lipid nanoparticles. To eradicate pandemics, present and future, a successful vaccine platform must enable rapid discovery, scalable manufacturing and global distribution. Here, we review current approaches to COVID-19 vaccine development and highlight the role of nanotechnology and advanced manufacturing.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Nanoestructuras/uso terapéutico , Pandemias/prevención & control , Neumonía Viral/prevención & control , Vacunas Virales/uso terapéutico , Betacoronavirus/inmunología , Betacoronavirus/patogenicidad , Investigación Biomédica/tendencias , COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Humanos , Nanotecnología/tendencias , Neumonía Viral/inmunología , Neumonía Viral/virología , SARS-CoV-2 , Vacunas Virales/inmunología
7.
ACS Appl Mater Interfaces ; 12(16): 19033-19043, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32267677

RESUMEN

In modern manufacturing, it is a widely accepted limitation that the parts patterned by an additive or subtractive manufacturing process (i.e., a lathe, mill, or 3D printer) must be smaller than the machine itself that produced them. Once such parts are manufactured, they can be postprocessed, fastened together, welded, or adhesively bonded to form larger structures. We have developed a foaming prepolymer resin for lithographic additive manufacturing, which can be expanded after printing to produce parts up to 40× larger than their original volume. This allows for the fabrication of structures significantly larger than the build volume of the 3D printer that produced them. Complex geometries comprised of porous foams have implications in technologically demanding fields such as architecture, aerospace, energy, and biomedicine. This manuscript presents a comprehensive screening process for resin formulations, detailed analysis of printing parameters, and observed mechanical properties of the 3D-printed foams.

8.
J Pharm Biomed Anal ; 41(4): 1251-9, 2006 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-16621411

RESUMEN

Establishing appropriate impurity specifications for active pharmaceutical ingredient (API) starting materials is an important component of the commercialization and registration of an API. Multiple sources and routes of manufacture of starting materials and the capability of the API synthetic process for tolerating impurities introduced with starting materials must be understood. A strategy for purity method development and use test evaluation of starting materials to aid in establishing quality requirements is described. Phenyl methyl amino propanol (PMAP), a starting material that may be used for fluoxetine hydrochloride and atomoxetine hydrochloride, is used to illustrate the quality evaluation strategy. Knowledge of actual and potential synthetic routes was used to predict potential impurities and guide purity method development. Multiple analytical methods that were semi-orthogonal in the nature of impurity retention (ion-pairing, ion interaction and hydrophilic interaction chromatographic modes) along with use tests were investigated.


Asunto(s)
Química Farmacéutica/métodos , Preparaciones Farmacéuticas/análisis , Control de Calidad , Cromatografía Liquida/métodos , Contaminación de Medicamentos , Estudios de Evaluación como Asunto
9.
Eur J Med Chem ; 37(1): 23-34, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11841872

RESUMEN

The metabolism of moxonidine, 4-chloro-N-(4,5-dihydro-1H-imidazol-2-yl)-6-methoxy-2-methyl-5-pyrimidinamine, LY326869, in rats, mice, dogs, and humans has been examined. At least 17 metabolites were identified or tentatively identified in the different species by HPLC, LC/MS and LC/MS/MS. The identities of seven of the major metabolites have been verified by independent synthesis. The metabolites are generally derived from oxidation and conjugation pathways. Oxidation occurred at the imidazolidine ring as well as the methyl at the 2 position of the pyrimidine ring. All seven metabolites were examined in the spontaneously hypertensive rats (3 mg kg(-1), i.v.) for pressure and heart rate. Only one, 2-hydroxymethyl-4-chloro-5-(imidazolidin-2-ylidenimino)-6-methoxypyrimidine, exerted a short-lasting decrease in blood pressure, albeit attenuated in magnitude compared to moxonidine.


Asunto(s)
Antihipertensivos/síntesis química , Antihipertensivos/metabolismo , Antihipertensivos/farmacología , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Imidazoles/síntesis química , Imidazoles/metabolismo , Imidazoles/farmacología , Administración Oral , Animales , Antihipertensivos/química , Perros , Humanos , Imidazoles/química , Ratones , Ratones Endogámicos , Oxidación-Reducción , Ratas , Ratas Endogámicas F344 , Relación Estructura-Actividad , Factores de Tiempo
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