![]() The exemption provision states that “an article or substance treated with, or containing, a pesticide to protect the article or substance itself (for example, paint treated with a pesticide to protect the paint coating, or wood products treated to protect the wood against insect or fungus infestation), if the pesticide is registered for such use.” If my clear waterbased roof coating contains the EPA-recommended maximum dosage of an already EPA-registered fungicide/mildewcide, can I claim on my marketing pieces that my coating contains an EPA-registered fungicide/ mildewcide as long as I do not specify the kinds of fungus/ mildew it prevents growth of on the film? Also, would I need to list that EPA-registered fungicide/ mildewcide on my label and literature? LC13-0656 08/30/13Ĥ0 CFR 152.25(a) provides an exemption from the requirements of registration for qualified treated articles or substances. Because all active ingredients must be listed, the absence of an active ingredient in the ingredient statement would indicate it is not in the product. These claims are therefore disallowable under FIFRA sections 2(q)(1)(A) and 12(a)(1)(E).Ĭonsumers can readily determine if a pesticide product contains an active ingredient (e.g., DEET) by reviewing the active ingredients listed on the front panel of the label in accordance with 40 CFR 156.10(g). Misleading comparative claims about the safety of the product versus other products also constitute misbranding under 40 CFR 156.10(a)(5)(iv) and (vii). Safety claims are considered false or misleading statements that constitute misbranding under 40 CFR 156.10(a)(5)(ix) and (x). This could give users the impression that products without a certain active ingredient are safe or safer than products with the active ingredient, which may be false or misleading. EPA is concerned that users might understand these types of statements to be safety claims. Advertising Claims Can a manufacturer advertise that their product does not contain a certain active ingredient (e.g., “DEET free”)? LC21-1208 10/14/21Ĭlaims such as “free of ” or “contains no ” may constitute misbranding and may need to be removed. Supplemental labeling (NOT distributor products)ġ.Name and address of producer/registrant. ![]() Exception to use in a manner not permitted (FIFRA Sec 2ee).In such cases, chemists usually define a standard by arbitrarily assigning a numerical value to one of the quantities, which allows them to calculate numerical values for the rest.įigure 1.6.2 Determining Relative Atomic Masses Using a Mass Spectrometer. We will encounter many other examples later in this text. It is actually rather common in chemistry to encounter a quantity whose magnitude can be measured only relative to some other quantity, rather than absolutely. Thus it is not possible to calculate absolute atomic masses accurately by simply adding together the masses of the electrons, the protons, and the neutrons, and absolute atomic masses cannot be measured, but relative masses can be measured very accurately. By measuring the relative deflection of ions that have the same charge, scientists can determine their relative masses (Figure 1.6.2). The extent of the deflection depends on the mass-to-charge ratio of the ion. When an electric field is applied, the ions are accelerated into a separate chamber where they are deflected from their initial trajectory by a magnetic field, like the electrons in Thomson’s experiment. First, electrons are removed from or added to atoms or molecules, thus producing charged particles called ions. The technique is conceptually similar to the one Thomson used to determine the mass-to-charge ratio of the electron. Scientists can measure relative atomic masses very accurately, however, using an instrument called a mass spectrometer. ![]() We can easily calculate the binding energy from the mass difference using Einstein's formula E=mc 2.īecause atoms are much too small to measure individually and do not have a charge, there is no convenient way to accurately measure absolute atomic masses. Although the difference in mass is small, it is extremely important because it is the binding energy of the nucleus. ![]() For example, the ratio of the masses of 1H (hydrogen) and 2H (deuterium) is actually 0.500384, rather than 0.49979 as predicted from the numbers of neutrons and protons present. Br\) or, more commonly, 79Br and 81Br.Īlthough the masses of the electron, the proton, and the neutron are known to a high degree of precision (Table 1.5.1), the mass of any given atom is not simply the sum of the masses of its electrons, protons, and neutrons.
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