Showing papers in "Regulatory Toxicology and Pharmacology in 1983"

TL;DR: A synthesis of available literature on uncertainty (safety) factors which are used to estimate acceptable daily intakes (ADIs) for toxicants is presented, revealing reasonable qualitative biological premises, as well as specific biological data that support both the use and choice of these factors.

TL;DR: Toxicity testing in several species by various routes of administration reveals an extremely low toxicity, the oral rat LD50 exceeding 40 g/kg, and a tolerance level for tissue residues of zeranol was calculated as 315 ppb.

TL;DR: Eisenia foetida, a commonly used test species, is much less sensitive to agricultural chemicals than other, native earthworms and is of doubtful utility for extrapolating laboratory data to field conditions, but when native soil organisms are used, such extrapolations show good general agreement.

TL;DR: Analytical values may not predict absolute intake of smoke, but they appear to inform about the relative intake smokers can expect from different brands in the 1-mg FTC tar class.

TL;DR: The purpose of this report is to present the scientific basis of risk assessment and to demonstrate that risk assessment can be used to make decisions about the safety of the authors' food supply.

TL;DR: The strengths and limitations of this carcinogen bioassay are discussed with emphasis upon the unresolved practical considerations, the interpretation of negative results, the significance of tumors induced in the presence of a high background incidence of naturally occurring tumors, and the difficulties in transspecies extrapolation.

TL;DR: In this paper, a quantitative risk assessment, using the multistage low-dose extrapolation model, found the (maximum likelihood) estimate of lifetime risk for excess cancers to be 620 per 100,000 at the OSHA permissible exposure level.

TL;DR: The toxicity of nickel (Ni) to mycelial growth of filamentous fungi and to replication of eubacteria, an actinomycete, and yeasts was influenced by various environmental abiotic factors.

TL;DR: Biotransformation and pharmacokinetic studies should be undertaken to obtain better understanding of the chemical's metabolism and excretion and to firmly establish whether the tolerance for maleic hydrazide should remain unchanged or whether the use of the compound should be more restricted.

TL;DR: An overview of the regulatory safety issues of these new products is given, which require careful consideration to ensure that risks inherent in those methods do not cause disease when these products are administered to human subjects.

TL;DR: Practices and regulations should be changed to provide the option of obtaining adequate information on the acute toxicity of a drug with fewer animals than the precise LD50 test demands.

TL;DR: This paper presents the two common approaches to toxicological evaluations and indicates that a deficiency of significant biological data, such as an unexpected toxic effect and the marked influence of modifying factors, can invalidate a toxicological evaluation.

TL;DR: Interspecies differences were demonstrated with respect to the occurrence of sodium nitrite-induced methemoglobin (METHB) in the erythrocytes of rats, dorset sheep, and normal humans, with the rats displaying approximately 25-33% of the sensitivity of sheep and human ery Throatcytes.

TL;DR: Physiological factors that affect the fate of drugs in the body and thereby have effects on their pharmacology and toxicology involve the systems that control absorption, distribution, metabolism, and excretion.

TL;DR: The good consistency of distribution patterns established by experiments with those established mathematically justifies the assumption that a reliable calculation method of distributionpatterns can be submitted as soon as the current work will be finished.

TL;DR: Modifications are proposed to the screening test with the object of making it more useful and realistic in predicting whether or not a chemical will be removed in sewage treatment.

TL;DR: Rats, sheep, and normal humans displayed a comparable sensitivity to copper acetate (3 mM)-induced changes in reduced glutathione (GSH) levels in vitro, but the human erythrocytes were more sensitive than either animal to methemoglobin (METHB) formation with the rat being least sensitive.

TL;DR: The effects of the physical components in the defluoridation showed a significant role in the control the accidental release of fluoride in the aquatic system.

TL;DR: The toxic effects of dichloromethane (DCM) are reviewed, human dose-response data, tolerance levels, and the effects of physical exercise and smoking on DCM toxicity are reported.

TL;DR: In laboratory animals, high-fat diets appear to play a role during the postinitiation phase of tumorigenesis, and additional factors must be considered when studying and interpreting the effects of dietary fat.

TL;DR: Examples of each type of classification system proposed which can be grouped into dose-dependent, mechanistic, and response-dependent classification systems in assessing the carcinogenic hazard of chemicals is explored.

TL;DR: It is suggested that the alkylating properties of dimethoate only in part may be responsible for its cytogenetic activity.

TL;DR: A physicochemical speciation scheme in tandem with bioassays identified the toxic fractions of the wastewater from a base metal refining and fertilizer complex.

TL;DR: A brief review of the history of risk assessment in the federal government may provide a point of reference and give a sense of current policy direction and a number of current activities likely to have a bearing on the direction of federal policy are discussed.

TL;DR: Suggestions include phaseout of the GRAS list, modification of the Delaney Clause, utilization of appropriate human testing in protocols for evaluating candidate food additives, development of improved animal tests for behavioral effects of food ingredients, and improvement in procedures for detection of hypersensitivity to food ingredients.

TL;DR: The human epidemiology data and the animal toxicity data of PCB exposure are reviewed, as well as risk assessment in general, and specific examples of risk assessment are presented in which animal data are extrapolated to humans, based on several levels of human exposure to PCBs in fish.

TL;DR: The legislative basis of the federal Canadian government's control of toxic chemicals is described and examples are given of the practical application, ranging from recommendations to a ban on the sale of the product.

TL;DR: The AIHC's principles have not been fully embedded in the legislative or regulatory processes of this country, but the opportunity now exists to get these principles and methodologies embeddedIn the laws as they are amended, in regulations as they were created, and in policies as they is devised.

TL;DR: The present discussion is concerned with risk management strategies under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Toxic Substances Control Act (TSCA).

TL;DR: The FAO/WHO Codex Alimentarius Commission publishes a Guide to Codex Maximum Limits for Pesticide Residues (1978) which gives both acceptable daily intake (ADI) values and maximum residue limit (MRL) values for many pesticides in raw agricultural commodities from crops on which their use is approved.