Ingestion/administration

Rosin has a low order of toxicity foUowing ingestion or skin contact. Rosin and its numerous derivatives have a number of permitted food packaging and other direct and indirect food contact uses throughout the world. Sanctioned uses appHcable in the United States are outlined in U.S. Food and Dmg Administration (U.S. FDA) Regulations (2). Material Safety Data Sheets (MSDSs) for specific rosins and thein derivatives should be consulted before thein use. 

Notify a physician immediately. A suggested procedure for physicians or nurses is intravenous administration of 0.3 g (10 mL of a 3% solution) of sodium nitrite at the rate of 2.5 mL/min followed by 12.5 g (50 mL of a 25% solution) of sodium thiosulfate at the same rate. Watch the patient for 24 to 48 h, especially in cases of ingestion or skin absorption. If symptoms reappear, repeat the injections in half the original amounts. These solutions should be kept readily available. In some cases, first aid personnel have been trained to use the intravenous medication subject to government regulations. 

Pharmacology. Disulfiram is almost completely absorbed after oral administration. Because it binds irreversibly to ALDH, renewed enzyme activity requires the synthesis of new enzyme. This feature creates the potential for the occurrence of a DER for at least 2 weeks after the last ingestion of disulfiram. Consequently, alcohol should be avoided during this period. 

The route of antigen administration can alter the speed of antigen access to the circulation and, thus, the systemic symptoms in anaphylaxis models. For example, allergen ingestion typically induces anaphylaxis that includes gastrointestinal symptoms, such as diarrhea [4]. These intestinal anaphylaxis models in mice are dependent on IgE-induced mast cell activation, and the release of PAF and serotonin (rather than histamine) [1,4]. 

In the total plasma response approach, the bioavailability of a compound is determined by measuring its plasma concentration at different times (up to weeks) after single or long-term ingestion of the compound from supplements or food sources. Generally, a plasma concentration-versus-time plot is generated, from which is determined the area-under-curve (AUC) value used as an indicator of the absorption of the componnd. Here, the term relative bioavailability is more appropriate since AUC valnes of two or more treatments are usually compared. This is in contrast to absolnte bioavailability for which the AUC value of the orally administered componnd is compared to that obtained with intravenous administration taken as a reference (100% absorption). 

Absorption across biological membranes is often necessary for a chemical to manifest toxicity. In many cases several membranes need to be crossed and the structure of both the chemical and the membrane need to be evaluated in the process. The major routes of absorption are ingestion, inhalation, dermal and, in the case of exposures in aquatic systems, gills. Factors that influence absorption have been reviewed recently. Methods to assess absorption include in vivo, in vitro, various cellular cultures as well as modelling approaches. Solubility and permeability are barriers to absorption and guidelines have been developed to estimate the likelihood of candidate molecules being absorbed after oral administration. ... 

For the majority of drugs, the preferred administration route is by oral ingestion which requires good intestinal absorption of drug molecules. Intestinal absorption is usually expressed as fraction absorbed (FA), expressing the percentage of initial dose appearing in a portal vein [15]. 

One major problem caused by Section 409 (c) (3) of the Federal Food, Drug and Cosmetic Act, commonly known as the Delaney Clause , which governed the registration of pesticides was the statement, No additive shall be deemed safe if it is found to induce cancer when ingested by man or animal,... . Dr Fred R. Shank, Director, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, in... 

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