Showing papers in "Regulatory Toxicology and Pharmacology in 1990"

TL;DR: Different methods for converting the dose-related toxicity of drugs from animals to humans are reviewed and linear extrapolations based on body weight equivalence are shown to be inaccurate unless species-specific conversion factors are used.

TL;DR: The relationships between soil lead and blood lead concentrations in residents in communities with high soil lead concentrations resulting from past mining and ore processing (milling) activities are compared to those derived from studies in urban communities or communities with operating smelters.

TL;DR: The principal findings of the adult study revealed that the four most reliable tracer elements based on recovery studies in a mass balance assessment yielded the following mean daily adult soil ingestion estimations: Al (77 mg), Si (5 mg), Y (53 mg), and Zr (22 mg).

TL;DR: This paper reviews the histories of some currently applied methodologies, draws on their best features, and proposes a logically and operationally attractive alternative that will work equally well for guidelines for exposures by other routes.

TL;DR: The importance of pharmacokinetic and receptor studies in the preclinical and clinical safety evaluation of candidate drugs is reviewed with reference to a number of recently developed drugs and the false prediction of adverse effects in man from toxicity manifested in experimental animals is exemplified.

TL;DR: The use of mathematical models of the mechanism of carcinogenic action and pharmacokinetic models for the metabolic activation of the parent compound to its reactive metabolite is discussed, along with other factors involved in the evaluation of carcinogen bioassay data.

TL;DR: The estimates presented here are the result of an extensive investigation of three data bases, many agency documents, and nearly 200 articles from 30 scientific journals, and are intended to reflect absorption by the average adult human.

TL;DR: The limitations of plasma concentrations in interpreting the toxicology of substances which are tissue-sequestered, which are subject to pharmacogenetic factors, or which show plasma concentrations that are not proportional to dose are discussed.

TL;DR: The profiling of new drug candidates for general pharmacological properties requires a systematic examination of the functional effects of agents in a variety of in vitro and in vivo assays, which provides valuable information to the preclinical pharmacologist with respect to the selectivity of new agents.

TL;DR: The carcinogenic potential of methidathion, a dimethoxyorganic phosphorus pesticide and cholinesterase inhibitor, was evaluated by the Health Effects Division of the Office of Pesticide Programs using a consensus peer review process and the EPA's guidelines for risk assessment as discussed by the authors.

TL;DR: A comparative hazard approach to formaldehyde regulation is offered as a supplement to the rigid evaluation protocols currently used based on a comparison of ingestion offormaldehyde in drinking water with ingestion of naturally occurring formaldehyde in foods.

TL;DR: The major differences between authorities were found to be the duration of chronic, repeated-dose tests and the design of reproduction studies, which emphasizes the need to harmonize these guidelines.

TL;DR: This work identifies the kinds of information that can be useful in this process, and indicates how each might most appropriately be used in the classification of chemical carcinogens.

TL;DR: A model is proposed for fish consumption advisories based on consensus-derived risk assessment values for common contaminants in fish and the latest risk assessment methods, which accounts in part for the expected toxicity to mixtures of chemicals.

TL;DR: The methodology by which USEPA calculated a lifetime HA of 2 micrograms/liter is presented and the differences in the derivation of the WQC and the HA are discussed.

TL;DR: Recent experimental evidence is reviewed and the gaps and inconsistencies in understanding of the relationship between exposure to crystalline silica and the two diseases of concern: silicosis and pulmonary neoplasia are identified.

TL;DR: It is concluded that the proposed test procedure provides much more information on the signs of acute toxicity, the course of the intoxication, the slope of the dose-effect curve, and the rate of recovery than does the standard LD50 test and the degree of distress and suffering of the animals is reduced.

TL;DR: In this article, the case of San Donnino is the starting point used to define the maximum tolerable environmental limits for complex mixtures of PCDDs and PCDFs.

TL;DR: In this article, an ambient water quality criterion for the protection of human health of 135 μg/liter is proposed when consumption of both contaminated water and fish is anticipated, and the proposed criterion is for drinking water alone.

TL;DR: Modifications to standard animal skin irritation test procedures have been evaluated against human skin irritation results and indicate that use of the Chamber offers the potential to reduce the number of animals used for skin irritation screening and eliminate the need for conducting multiple tests to satisfy different governmental requirements.

TL;DR: The results show that consumers expect a cigarette grading message predictive of actual intake from different brands and the current message based on standard analytical yields does not meet this requirement and needs modification.

TL;DR: This paper describes how a "relative decision-making" technique applicable to complex mixtures can supplement the "absolute" approach currently used to derive permissible exposure concentrations for hazardous substances.

TL;DR: The safety margin approach based on human health effects showed that TRI levels are well within the safety margin for the human no-observable-effect level (10,000 times lower), and the environmental occurrence of TRI does not represent a significant health risk to the general population or the population in areas close to industrial activities.

TL;DR: The toxicokinetic relationships and the absence of clear experimental dose-rate effects suggest that the current STEL for benzene is unwarranted, assuming that 8-hr average exposures are kept below 1 ppm, and health professionals focus upon long-term exposures to benzene received by large numbers of workers.

TL;DR: Adverse effects in controlled prospective studies in humans and in actual use situations in community water supplies have as yet failed to reveal clear evidence of adverse health effects, but dialysis patients in carefully controlled facilities may be at no greater risk than the general population.

TL;DR: The legal principles that underlie the interrelated definitions of "safe," "significant risk," and "acceptable risk" are examined in light of the major court decisions on benzene and vinyl chloride.

TL;DR: The potential water disinfection by-product chloroacetic acid (CA) was determined to be over eight times more toxic to the "embryonic" developmental portion of the assay than it was to the adults.

TL;DR: Results of prerelease contained growth chamber and field experiments demonstrated that the scientific risk assessment methodology adopted by Monsanto and approved by the U.S. Environmental Protection Agency was appropriate and comprehensive and the deliberate introduction of a GEM did not pose unacceptable or unforeseen risks to human health or the environment.