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Alexandria, VA, United States

Moghissi A.A.,Microbiology and Immunology | Moghissi A.A.,George Mason University | Moghissi A.A.,Institute for Regulatory Science | Moghissi A.A.,Potomac Institute for Policy Studies | And 4 more authors.
Critical Reviews in Biotechnology | Year: 2016

Historically, agricultural development evolved in three phases. During the first phase the plants were selected on the basis of the availability of a plant with desirable properties at a specific location. The second phase provided the agricultural community with crossbreeding plants to achieve improvement in agricultural production. The evolution of biological knowledge has provided the ability to genetically engineer (GE) crops, one of the key processes within genetically modified organisms (GMO). This article uses golden rice, a species of transgenic Asian rice which contains a precursor of Vitamin A in the edible part of the plant as an example of GE/GMO emphasizing Chinese experience in agricultural evolution. It includes a brief review of agricultural evolution to be followed by a description of golden rice development. Golden rice was created as a humanitarian project and has received positive comments by the scientific community and negative voices from certain environmental groups. In this article, we use the Best Available Science (BAS) Concept and Metrics for Evaluation of Scientific Claims (MESC) derived from it to evaluate claims and counter claims on scientific aspects of golden rice. This article concludes that opposition to golden rice is based on belief rather than any of its scientifically derived nutritional, safety or environmental properties. © 2015 Informa Healthcare USA, Inc. Source

Ricci P.F.,Holy Names University | Ricci P.F.,Xiamen University | Ricci P.F.,University of Massachusetts Amherst | Straja S.R.,Institute for Regulatory Science
Dose-Response | Year: 2012

Both the linear (at low doses)-no-threshold (LNT) and the threshold models (Sshapes) dose-response lead to no benefit from low exposure. We propose three new models that allow and include, but do not require - unlike LNT and S-shaped models - this strong assumption. We also provide the means to calculate benefits associated with bi-phasic biological behaviors, when they occur and propose: 1. Three hormetic (phasic) models: the J-shaped, inverse J-shaped, the min-max, and 2. Method for calculating the direct benefits associated with the J and inverse J- shaped models. The J-shaped and min-max models for mutagens and carcinogenic agents include an experimentally justified repair stage for toxic and carcinogenic damage. We link these to stochastic transition models for cancer and show how abrupt transitions in cancer hazard rates, as functions of exposure concentrations and durations, can emerge naturally in large cell populations even when the rates of cell-level events increase smoothly (e.g., proportionally) with concentration. In this very general family of models, J-shaped doseresponse curves emerge. These results are universal, i.e., independent of specific biological details represented by the stochastic transition networks. Thus, using them suggests a more complete and realistic way to assess risks at low doses or dose-rates. © 2012 University of Massachusetts. Source

Alan Moghissi A.,Institute for Regulatory Science | Alan Moghissi A.,George Mason University | Alan Moghissi A.,Potomac Institute for Policy Studies | McBride D.K.,Institute for Regulatory Science | And 3 more authors.
Health Physics | Year: 2014

This paper starts by describing the historical evolution of assessment of biologic effects of ionizing radiation leading to the linear non-threshold (LNT) system currently used to regulate exposure to ionizing radiation. The paper describes briefly the concept of Best Available Science (BAS) and Metrics for Evaluation of Scientific Claims (MESC) derived for BAS. It identifies three phases of regulatory science consisting of the initial phase, when the regulators had to develop regulations without having the needed scientific information; the exploratory phase, when relevant tools were developed; and the standard operating phase, when the tools were applied to regulations. Subsequently, an attempt is made to apply the BAS/MESC system to various stages of LNT. This paper then compares the exposure limits imposed by regulatory agencies and also compares them with naturally occurring radiation at several cities. Controversies about LNT are addressed, including judgments of the U.S. National Academies and their French counterpart. The paper concludes that, based on the BAS/MESC system, there is no disagreement between the two academies on the scientific foundation of LNT; instead, the disagreement is based on their judgment or speculation. © 2014 Health Physics Society. Source

Alan Moghissi A.,Institute for Regulatory Science | Love B.R.,Institute for Regulatory Science | Straja S.R.,Institute for Regulatory Science
Dose-Response | Year: 2012

The Linear Non-Threshold (LNT) process is used by virtually all governmental agencies to compute incidence of cancer as a consequence of exposure to a carcinogen. This comment applies the concept of Best Available Science (BAS) Metrics for Evaluation of Scientific Claims (MESC) derived from BAS to issues related to reliability of LNT hypothesis. This paper identifies the level of maturity of the LNT hypothesis and the associated uncertainties. Copyright © 2012 University of Massachusetts. Source

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