https://www.who.int/foodsafety/chem/2005_WHO_TEFs_ToxSci_2006.pdf

The 2005 World Health Organization reevaluation of human and Mammalian toxic equivalency factors for dioxins and dioxin-like compounds.

Heavy metal pollution in the environment and their toxicological effects on humans

Metal and Silicate Particles Including Nanoparticles Are Present in Electronic Cigarette Cartomizer Fluid and Aerosol Monique Williams 1 , Amanda Villarreal 1 , Krassimir Bozhilov 2 , Sabrina Lin 1 , Prue Talbot 1 * 1 Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, California, United States of America, 2 Central Facility for Advanced Microscopy and Microanalysis, University of California Riverside, Riverside, California, United States of America Abstract Background: Electronic cigarettes (EC) deliver aerosol by heating fluid containing nicotine. Cartomizer EC combine the fluid chamber and heating element in a single unit. Because EC do not burn tobacco, they may be safer than conventional cigarettes. Their use is rapidly increasing worldwide with little prior testing of their aerosol. Objectives: We tested the hypothesis that EC aerosol contains metals derived from various components in EC. Methods: Cartomizer contents and aerosols were analyzed using light and electron microscopy, cytotoxicity testing, x-ray microanalysis, particle counting, and inductively coupled plasma optical emission spectrometry. Results: The filament, a nickel-chromium wire, was coupled to a thicker copper wire coated with silver. The silver coating was sometimes missing. Four tin solder joints attached the wires to each other and coupled the copper/silver wire to the air tube and mouthpiece. All cartomizers had evidence of use before packaging (burn spots on the fibers and electrophoretic movement of fluid in the fibers). Fibers in two cartomizers had green deposits that contained copper. Centrifugation of the fibers produced large pellets containing tin. Tin particles and tin whiskers were identified in cartridge fluid and outer fibers. Cartomizer fluid with tin particles was cytotoxic in assays using human pulmonary fibroblasts. The aerosol contained particles .1 m m comprised of tin, silver, iron, nickel, aluminum, and silicate and nanoparticles (,100 nm) of tin, chromium and nickel. The concentrations of nine of eleven elements in EC aerosol were higher than or equal to the corresponding concentrations in conventional cigarette smoke. Many of the elements identified in EC aerosol are known to cause respiratory distress and disease. Conclusions: The presence of metal and silicate particles in cartomizer aerosol demonstrates the need for improved quality control in EC design and manufacture and studies on how EC aerosol impacts the health of users and bystanders. Citation: Williams M, Villarreal A, Bozhilov K, Lin S, Talbot P (2013) Metal and Silicate Particles Including Nanoparticles Are Present in Electronic Cigarette Cartomizer Fluid and Aerosol. PLoS ONE 8(3): e57987. doi:10.1371/journal.pone.0057987 Editor: Stephen J. Johnson, University of Kansas, United States of America Received August 31, 2012; Accepted January 30, 2013; Published March 20, 2013 Copyright: s 2013 Willliams et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was supported by grants from the Tobacco-Related Disease Research Program (TRDRP) to PT, a Cornelius Hopper Award to MW, a MARC National Institutes of Health (NIH) fellowship to AV, and a TRDRP Postdoctoral Fellowship to SL. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: talbot@ucr.edu As EC have evolved, the atomizer and cartridge have often been combined into a single unit called a ‘‘cartomizer’’ [6]. Recent studies have shown that EC can deliver nicotine to users, although not always as effectively as conventional cigarettes [7,8]. EC may help smokers overcome nicotine addiction and/or serve as nicotine delivery devices that are safer than tobacco burning cigarettes [9,10]. EC have helped some smokers stop using conventional brands and either quit smoking entirely or switch to the presumably safer EC [11,12]. Their effectiveness in this regard may be aided by the hand-mouth motion that the EC provides, unlike nicotine patches and gum. Some users have reported to us that EC have helped them break nicotine addiction, but not the hand-mouth addiction associated with smoking. Because EC do not burn tobacco, they do not produce the numerous chemicals found in conventional tobacco smoke. For Introduction Electronic cigarettes (EC) are generally manufactured in China and are rapidly gaining acceptance in many countries [1,2]. In the United States, EC are available on the Internet, in malls, and in local shops. They have become an integral part of the environment without much information regarding the quality control used in their manufacture or their health effects [3]. EC deliver aerosolized nicotine to users and may serve as a surrogate for conventional tobacco-containing cigarettes [4,5]. Puffing an EC activates a battery that in turn heats liquid containing flavoring, a humectant(s) such as propylene glycol or vegetable glycerin, and nicotine. Some models, such as the one used in this study, do not contain nicotine. Early models of EC had separate atomizers for heating and cartridges for holding fluid [3]. PLOS ONE | www.plosone.org March 2013 | Volume 8 | Issue 3 | e57987

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0057987&type=printable

Metal and Silicate Particles Including Nanoparticles Are Present in Electronic Cigarette Cartomizer Fluid and Aerosol

Heavy metals are released into the environment by both anthropogenic and natural sources. Highly reactive and often toxic at low concentrations, they may enter soils and groundwater, bioaccumulate in food webs, and adversely affect biota. Heavy metals also may remain in the environment for years, posing long-term risks to life well after point sources of heavy metal pollution have been removed. In this review, we compile studies of the community-level effects of heavy metal pollution, including heavy metal transfer from soils to plants, microbes, invertebrates, and to both small and large mammals (including humans). Many factors contribute to heavy metal accumulation in animals including behavior, physiology, and diet. Biotic effects of heavy metals are often quite different for essential and non-essential heavy metals, and vary depending on the specific metal involved. They also differ for adapted organisms, including metallophyte plants and heavy metal-tolerant insects, which occur in naturally high-metal habitats (such as serpentine soils) and have adaptations that allow them to tolerate exposure to relatively high concentrations of some heavy metals. Some metallophyte plants are hyperaccumulators of certain heavy metals and new technologies using them to clean metal-contaminated soil (phytoextraction) may offer economically attractive solutions to some metal pollution challenges. These new technologies provide incentive to catalog and protect the unique biodiversity of habitats that have naturally high levels of heavy metals.

/pdf/transfer-of-heavy-metals-through-terrestrial-food-webs-a-az81f8ytbd.pdf

Transfer of heavy metals through terrestrial food webs: a review

Prioritizing research for trace pollutants and emerging contaminants in the freshwater environment.

This public health statement tells you about manganese and the effects of exposure to it.The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites are then placed on the National Priorities List (NPL) and are targeted for long-term federal clean-up activities. Manganese has been found in at least 869 of the 1,699 current or former NPL sites. Although the total number of NPL sites evaluated for this substance is not known, the possibility exists that the number of sites at which manganese is found may increase in the future as more sites are evaluated. This information is important because these sites may be sources of exposure and exposure to this substance may harm you.When a substance is released either from a large area, such as an industrial plant, or from a container, such as a drum or bottle, it enters the environment. Such a release does not always lead to exposure. You can be exposed to a substance only when you come in contact with it. You may be exposed by breathing, eating, or drinking the substance, or by skin contact.If you are exposed to manganese, many factors will determine whether you will be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with it. You must also consider any other chemicals you are exposed to and your age, sex, diet, family traits, lifestyle, and state of health.

Toxicological Profile for Manganese

Using the ATSDR Guidance Manual for the Assessment of Joint Toxic Action of Chemical Mixtures

https://www.tera.org/Publications/Teuschler%20et%20al%201999.pdf

Peter McClure

Papers

Toxicological Profile for Manganese

Using the ATSDR Guidance Manual for the Assessment of Joint Toxic Action of Chemical Mixtures

Health Risk above the Reference Dose for Multiple Chemicals

Public health assessment of hexachlorobenzene

Persistent chemicals found in breast milk and their possible interactions