Impurities thresholds

Photodetectors exhibit well-defined, cutoff wavelength thresholds, the positions of which are determined by the magnitudes of the band gap activation energy, E, or impurity-activation energy, E. The cutoff wavelength, corresponds to a photochemical activation energy, E, where. 

Similarly, in processes where the listed toxic chemical occurs at a concentration below the de minimis level and is processed to a concentration above the de minimis level, the portion of the process where the toxic chemical is present above the de minimis level must be considered lor threshold and release determinations, lor example, an impurity contained in a solvent that is concentrated to above the de minimis level in a process. Beneficiation activities involving listed toxic chemicals present in ores, natural gas, and crude oil are an exception and require threshold and release determinations regardless of concentration of the listed toxic chemical(s) involved in the beneficiation process. 

The guideline on impurities in new medicinal products parallels the drug substance text, but the designated thresholds concern only degradation products. The thresholds should be applied to the product at the end of its shelf-life, as that is when the greatest level of degradation is expected to have occurred. 

Dioxane is an impurity present in alcohol ethoxy sulfates formed during sulfation of the ethoxylated alcohol. 1,4-Dioxane is a carcinogen in rats and mice [312-314] and has been considered as a possible carcinogen to humans [315-317]. However, the no-effect dose in rats is equivalent to a daily intake of dioxane of 9.6-19.0 mg/kg/day, which corresponds to 0.672 g/day for humans. In other studies it has been determined that the threshold for onset of human toxicity of 1,4-dioxane lies above an intake of 76 mg/kg in adult males [318]. Although it seems to be demonstrated that amounts up to 1000 ppm of... 

The achievement of the corresponding monocrystals of sufficient optical and crystalline quality is made possible only after very thorough purification. Chemical impurities are known to disturb the crystal lattice through the occurence of twins, veils dislocations, rounding-off of faces ultimately quenching further growth. Any crystalline defect dramatically increases the residual absorption coefficient and lowers the optical damage threshold. 

The crude product is at once purified according to the usual methods of organic chemistry. Then it is essential to lower the impurities rate to a threshold compatible with crystal growth and especially with the use of the materials for nonlinear optics (10 to 100 parts per million). 

On a national basis, Toys require compliance of limits for the same impurities as outlined under food packaging. In particular trace metal amounts have to be considered as well as threshold limits for aromatic amines, soluble in 0,07 m hydrochloric acid. The trace amount of cancerogenic amine should, depending on the various countries, not exceed 5 or 10 ppm. 

Given the role that low thresholds of 5-AT and 1H tetrazole impurities clearly play in the successful synthesis of DBX-1 from NaNT, we endeavoured to develop a procedure for synthesizing pure NaNT as efficiently as possible, while avoiding the tedious, time consuming, and reduced yield Cu11 titration and filtration, which is currently required. As an added refinement, we also desired to eliminate the handling of the intermediate acid salt of copper(II) 5-nitrotetrazolate, Cu(NT)2 HNT ... 

The outcome of planning should include the generation of a method definition requirement document (MDRD) in which all stake holders agree, prior to method development, on the critical attributes of the method. Considerations such as what impurities/degradation products should be monitored, requisite reporting thresholds, the need for an MS-compatible method, if identical methods for DP and DS are required, etc., should be clearly decided and agreed upon by all stakeholders. 

Filtered and unfiltered samples are compared for the API and the impurities. Additionally, there should be no new impurities higher than the reporting threshold detected. 

The reporting threshold is a limit above which (>) an impurity needs to be reported. The reporting threshold is determined as described by the... 

ICH guidelines, and is generally 0.05% for DS and 0.10% for DP methods. Any impurity above this level should be reported. Especially for stability indicating methods, it may be valuable to apply a lower level as the reporting threshold to allow for a better trending process for degradation products at levels below 0.05% and 0.10% for DS and DP methods, respectively. 

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