Stewardship challenges abortion: A proposed means to mitigate abortion's social divisiveness.

Since 1973 the legislated constitutional right to abortion has produced a political dichotomy (anti-abortion versus pro-abortion) within the United States, even while witnessing a gradual decline in the rate of abortions. A third paradigm, moral stewardship, is advanced as an effective means to ameliorate this social divisiveness. Incorporating the concept of stewardship into deliberations of pregnancy termination would require recognition, through fact-based education programs, of the life circumstances that prompt the consideration to terminate a pregnancy.

Derivation of a reference dose and drinking water equivalent level for 1,2,3-trichloropropane.

In some US potable water supplies, 1,2,3-trichloropropane (TCP) has been present at ranges of non-detect to less than 100 ppb, resulting from past uses. In subchronic oral studies, TCP produced toxicity in kidneys, liver, and other tissues. TCP administered by corn oil gavage in chronic studies produced tumors at multiple sites in rats and mice; however, interpretation of these studies was impeded by substantial premature mortality.

Human uptake of persistent chemicals from contaminated soil: PCDD/Fs and PCBs.

Trace amounts of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are ubiquitous in the environment. Because of industrial activity, other human activities, and accidents, higher concentrations of these chemicals may be present in soil, in residential and recreational areas. Human uptake of these chemicals from such soils has been assumed by regulators, and people contacting such soils may be concerned about potential adverse health effects.

Estimation of safe dietary intake levels of acrylamide for humans.

Acrylamide (AA), a human neurotoxicant and rat tumorigen, is produced in starchy foods when cooked. AA is also an industrial chemical used in polyacrylamide production. A safety evaluation of ingested AA by humans was conducted using a newly developed, state-of-the-art physiologically-based toxicokinetic (PBPK or PBTK) model to compare internal doses of AA and its metabolite glycidamide (GA) in humans and rats.

Development of a physiologically-based toxicokinetic model of acrylamide and glycidamide in rats and humans.

Physiologically-based toxicokinetic ("pharmacokinetic") (PBPK or PBTK) modeling can be used as a tool to compare internal doses of acrylamide (AA) and its metabolite glycidamide (GA) in humans and rats. An earlier PBTK model for AA and GA in rats was refined and extended to humans based on new data. With adjustments to the previous parameters, excellent fits to a majority of the data for male Fisher 344 rats were obtained.

Derivation of a drinking water equivalent level (DWEL) related to the maximum contaminant level goal for perfluorooctanoic acid (PFOA), a persistent water soluble compound.

Water soluble compounds persistent in humans and the environment pose a challenge for estimating safe levels in tap water. A viable approach to estimate a drinking water equivalent level (DWEL) for perfluorooctanoic acid (PFOA) was applied to its extensive relevant information from human and laboratory animal studies. PFOA has been identified at 3.

Updated weight of evidence for an association between adverse reproductive and developmental effects and exposure to disinfection by-products.

Disinfection by-products (DBP) are produced when water is treated with chemical disinfectants. Some toxicological and epidemiological studies suggest an association between DBP exposure and adverse reproductive and developmental effects. In a previous critical review, [Graves, C.

Harmonization of thresholds for primary skin irritation from results of human repeated insult patch tests and laboratory animal skin irritation tests.

Classification of a chemical or chemical product as a primary skin irritant using laboratory animal tests has been defined rigorously and codified in Consumer Products Safety Commission (CPSC) regulations. However, no regulatory agency, including the CPSC, has defined a primary skin irritant threshold for human repeat insult patch tests (RIPTs) that are typically conducted on products, such as cosmetics, anticipated to come into direct contact with humans. Further more, the protocols for animal and human tests are significantly different, as are the schemes for grading responses.