Ecotoxicity testing: science, politics and ethics

Animal welfare organisations have long been concerned about the use of animals for ecotoxicity testing. Ecotoxicity testing is a necessary part of the statutory risk assessment of chemicals that may be released into the environment. It is sometimes also carried out during the development of new chemicals and in the investigation of pollution in the field. This review considers the existing requirements for ecotoxicity testing, with particular reference to practices in the European Union, including the recent REACH system proposals, before discussing criticisms that have been made of existing practices for environmental risk assessment. These criticisms have been made on scientific and ethical grounds, as well as on questions of cost. A case is made for greater investment in the development of alternative testing methods, which could improve the science, as well as serving the cause of animal welfare. It has frequently been suggested that the statutory requirements for environmental risk assessment are too rigid and bureaucratic. A case is made for flexibility and the greater involvement of scientists in the risk assessment procedure, in the interests of both improved science and improved animal welfare.     

Stem cell plasticity, cell fusion, and transdifferentiation

One of the most contentious issues in biology today concerns the existence of stem cell plasticity. The term "plasticity" refers to the capacity of tissue-derived stem cells to exhibit a phenotypic potential that extends beyond the differentiated cell phenotypes of their resident tissue. Although evidence of stem cell plasticity has been reported by multiple laboratories, other scientists have not found the data persuasive and have remained skeptical about these new findings. This review will provide an overview of the stem cell plasticity controversy. We will examine many of the major objections that have been made to challenge the stem cell plasticity data. This controversy will be placed in the context of the traditional view of stem cell potential and cell phenotypic diversification. What the implications of cell plasticity are, and how its existence may modulate our present understanding of stem cell biology, will be explored. In addition, we will examine a topic that is usually not included within a discussion of stem cell biology--the direct conversion of one differentiated cell type into another. We believe that these observations on the transdifferentiation of differentiated cells have direct bearing on the issue of stem cell plasticity, and may provide insights into how cell phenotypic diversification is realized in the adult and into the origin of cell phenotypes during evolution.     

International research ethics: progress, but not perfection

To the uninitiated researcher, bioethics can be a confusing and sometimes bureaucratic process. The recent debates in international research ethics have both increased understanding of contentious issues while extending confusion to the international arena. Here, we attempt to demystify bioethics, or more specifically international research ethics, by defining ethics in the context of morality, reviewing core Western ethical principles, and highlighting challenges in international research ethics.