Representatives of the developers of modern agricultural biotechnology are proposing a tiered approach for conducting non-target organism risk assessment for genetically modified (GM) plants in Europe. The approach was developed by the Technical Advisory Group of the EuropaBio Plant Biotechnology Unit (http://www.europabio.org/TAG.htm) and complements other international activities to harmonize risk assessment. In the European Union (EU), the principles and methods to be followed in an environmental risk assessment for the placing on the market of GM plants are laid out in Annex II of Directive 2001/18/EC on the deliberate release into the environment of GMOs, Commission Decision 2002/623/EC and Regulation (EC) No. 1829/2003. Additional information is provided in the European Food Safety Authority guidance document of 2004. However, risk assessment for effects to non-target organisms could benefit from further clarification and remains the subject of much discussion in Europe. The industry-wide approach developed by EuropaBio is based on the fundamental steps of risk evaluation, namely hazard and exposure assessment. It follows a structured scheme including assessment planning, product characterization and assessment of hazard/exposure (Tier 0), single high dose and dose response testing (Tier 1), refined hazard characterization and exposure assessment (Tier 2) and further refined risk assessment experiments (Tier 3). An additional tier (Tier 4) was included to reflect the fact that post-market activities such as monitoring are required under Directive 2001/18/EC. The approach is compatible with conditions of commercial release in the EU and around the world.
In der folgenden Aufgabe wird die Winkler‐Titration beschrieben, die seit über 100 Jahren zur Bestimmung des Sauerstoffgehaltes in Wasserproben verwendet wird. Zunächst werden mögliche Fehlerquellen betrachtet und die zugrunde liegenden Reaktionen diskutiert, bevor die Methode anhand eines Rechenbeispiels praktisch veranschaulicht wird. Am Ende wird die Aufgabe durch einen kurzen, interdisziplinären Exkurs zu verwandten Meereswissenschaften abgerundet.
Die folgende Aufgabe widmet sich den Funden von weißem Phosphor an der Ostseeküste, bei denen durch die Verwechslungsgefahr mit Bernstein regelmäßig schlimme Verletzungen auftreten. Dabei wird zunächst die Reaktivität von weißem Phosphor anhand dessen Verbrennungsreaktion diskutiert, bevor auf die zivile Nutzung von Phosphor in Form von Streichhölzern eingegangen wird. Am Ende wird die Aufgabe durch einen praktischen Exkurs zu verschiedenen Streichholzarten abgerundet.
Introduction
A wide array of alternative nicotine delivery devices (ANDD) has been developed and they are often described as less harmful than combustible cigarettes. This work compares the chemical emissions of three ANDD in comparison to cigarette smoke. All the tested ANDD are characterized by not involving combustion of tobacco.
Method
Single photon ionization time-of-flight mass spectrometry (SPI-TOFMS) is coupled to a linear smoking machine, which allows a comprehensive, online analysis of the gaseous phase of the ANDD aerosol and the conventional cigarette smoke (CC). The following devices were investigated in this study: a tobacco cigarette with a glowing piece of coal as a heating source, an electric device for heating tobacco and a first-generation electronic cigarette. Data obtained from a standard 2R4F research cigarette are taken as a reference.
Results
The puff-by-puff profile of all products was recorded. The ANDD show a substantial reduction or complete absence of known harmful and potentially harmful substances compared to the CC. In addition, tar substances (i.e. semivolatile and low volatile aromatic and phenolic compounds) are formed to a much lower extent. Nicotine, however, is supplied in comparable amounts except for the investigated electronic cigarette.
Conclusions
The data shows that consumers switching from CC to ANDD are exposed to lower concentrations of harmful and potentially harmful substances. However, toxicological and epidemiological studies must deliver conclusive results if these reduced exposures are beneficial for users.
Implication
The comparison of puff-resolved profiles of emissions from different tobacco products, traditional and alternative, may help users switch to lower emission products. Puff-resolved comparison overcomes technical changes, use modes between products and may help in their regulation.
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