Joel Tickner

Health risks posed by use of Di-2-ethylhexyl phthalate (DEHP) in PVC medical devices: a critical review.

BACKGROUND Polyvinyl chloride plastics (PVC), made flexible through the addition of di-2-ethylhexyl phthalate (DEHP), are used in the production of a wide array of medical devices. From the late 1960s, leaching of DEHP from PVC medical devices and ultimate tissue deposition have been documented. METHODS A critical review of DEHP exposure, metabolism, and toxicity data from human and animals studies was undertaken. A brief analysis of alternatives to DEHP-plasticized PVC for use in medical device manufacture was completed. RESULTS DEHP leaches in varying concentrations into solutions stored in PVC medical devices. Certain populations, including dialysis patients and hemophiliacs may have long-term exposures to clinically important doses of DEHP, while others, such as neonates and the developing fetus, may have exposures at critical points in development. In vivo and in vitro research links DEHP or its metabolites to a range of adverse effects in the liver, reproductive tract, kidneys, lungs, and heart. Developing animals are particularly susceptible to effects on the reproductive system. Some adverse effects in animal studies occur at levels of exposure experienced by patients in certain clinical settings. DEHP appears to pose a relatively low risk of hepatic cancer in humans. However, given lingering uncertainties about the relevance of the mechanism of action of carcinogenic effects in rodents for humans and interindividual variability, the possibility of DEHP-related carcinogenic responses in humans cannot be ruled out. CONCLUSIONS The observed toxicity of DEHP and availability of alternatives to many DEHP-containing PVC medical devices presents a compelling argument for moving assertively, but carefully, to the substitution of other materials for PVC in medical devices. The substitution of other materials for PVC would have an added worker and community health benefit of reducing population exposures to DEHP, reducing the creation of dioxin from PVC production and disposal, and reducing risks from vinyl chloride monomer exposure.

Reenergizing Public Health Through Precaution

The precautionary principle has provoked a spirited debate among environmentalists worldwide, but it is equally relevant to public health and shares much with primary prevention. Its central components are (1) taking preventive action in the face of uncertainty; (2) shifting the burden of proof to the proponents of an activity; (3) exploring a wide range of alternatives to possibly harmful actions; and (4) increasing public participation in decision making. Precaution is relevant to public health, because it can help to prevent unintended consequences of well-intentioned public health interventions by ensuring a more thorough assessment of the problems and proposed solutions. It can also be a positive force for change. Three aspects are stressed: promoting the search for safer technologies, encouraging greater democracy and openness in public health policy, and stimulating reevaluation of the methods of public health science.

Late lessons from early warnings for nanotechnology

A new technology will only be successful if those promoting it can show that it is safe, but history is littered with examples of promising technologies that never fulfilled their true potential and/or caused untold damage because early warnings about safety problems were ignored. The nanotechnology community stands to benefit by learning lessons from this history.

Precaution, Environmental Science, and Preventive Public Policy

The Lowell Center for Sustainable Production has sought to engage scientists, policy-makers, advocates, and students in a broad public discussion about whether the tools and methods of environmental science and its integration in policy are adequate to address complex, highly uncertain environmental and health risks. It did so in an International Summit on Science and the Precautionary Principle and a recent collection of analyses stemming from the summit. Here, the author summarizes some summit recommendations to overcome barriers and build momentum for a vision for science and policy that better reflects uncertainty and complexity in natural systems. Appended is a summit statement on the subject.

Community-initiated breast cancer and environment studies and the precautionary principle.

The precautionary principle implies the need for research paradigms that contribute to “strength of the evidence” assessments of the plausibility of health effects when scientific uncertainty is likely to persist and prevention is the underlying goal. Previous discussions of science that inform precautionary decision making are augmented by examining three activist-initiated breast cancer and environment studies—the Long Island, New York, and Cape Cod, Massachusetts, studies and the National Institute of Environmental Health Sciences breast cancer and environment centers. These studies show how the choice of research questions affects the potential of results to inform action. They illustrate a spectrum of public involvement, population- and individual-level epidemiologic study designs, and the crucial importance of developing and applying new exposure assessment methods. The exposure studies are key because they are critical in assessing plausibility (without exposure to a causal agent, there is no health effect), are prerequisite to health studies, and identify preventable exposures that could be reduced by precautionary policies, even in the absence of strong evidence of harm. The breast cancer studies have contributed to environmental and biological sampling programs for endocrine-disrupting compounds in drinking water and household air and dust and the application of geographic information systems for surveillance and historical exposure assessment. They leave unanswered questions about when to invest in large epidemiologic studies, when negative results are sufficient, and how to pursue ambiguous positive results in further research and policy.

The precautionary principle and risk‐risk tradeoffs

In this paper we examine cases commonly characterised as risk‐risk tradeoffs (i.e., creating new risks while solving existing ones), in an attempt to learn lessons that can be valuable for future regulatory decision‐making. A broad range of environmental and health literature was reviewed and numerous cases of proclaimed risk‐risk tradeoffs were analysed in order to determine: 1) why regulatory measures were initially taken, 2) why these measures caused a countervailing risk to emerge, 3) how tradeoffs could have been avoided, and 4) whether the case is a good example of a risk‐risk tradeoff. The analysis reveals that only a small number of these cases can actually be considered risk‐risk tradeoffs. In a large number of cases safer alternatives are and were available at the time decisions were made. In some cases the proclaimed risk‐risk tradeoff simply did not exist or occur, and in some cases countervailing risks were ignored for reasons unknown. In many cases, the countervailing risks could have been anticipated and avoided by proactively seeking safer alternatives, completing a tradeoff and impact assessment, or increasing stakeholder input in the decision‐making process. We conclude that concerns about risk‐risk tradeoffs are not a reasonable argument against future application of the precautionary principle. Indeed, sound decision‐making processes in the face of uncertainty should always consider and attempt to mitigate reasonable risk‐risk tradeoffs.

Alternatives Assessment Frameworks: Research Needs for the Informed Substitution of Hazardous Chemicals

Background Given increasing pressures for hazardous chemical replacement, there is growing interest in alternatives assessment to avoid substituting a toxic chemical with another of equal or greater concern. Alternatives assessment is a process for identifying, comparing, and selecting safer alternatives to chemicals of concern (including those used in materials, processes, or technologies) on the basis of their hazards, performance, and economic viability. Objectives The purposes of this substantive review of alternatives assessment frameworks are to identify consistencies and differences in methods and to outline needs for research and collaboration to advance science policy practice. Methods This review compares methods used in six core components of these frameworks: hazard assessment, exposure characterization, life-cycle impacts, technical feasibility evaluation, economic feasibility assessment, and decision making. Alternatives assessment frameworks published from 1990 to 2014 were included. Results Twenty frameworks were reviewed. The frameworks were consistent in terms of general process steps, but some differences were identified in the end points addressed. Methodological gaps were identified in the exposure characterization, life-cycle assessment, and decision–analysis components. Methods for addressing data gaps remain an issue. Discussion Greater consistency in methods and evaluation metrics is needed but with sufficient flexibility to allow the process to be adapted to different decision contexts. Conclusion Although alternatives assessment is becoming an important science policy field, there is a need for increased cross-disciplinary collaboration to refine methodologies in support of the informed substitution and design of safer chemicals, materials, and products. Case studies can provide concrete lessons to improve alternatives assessment. Citation Jacobs MM, Malloy TF, Tickner JA, Edwards S. 2016. Alternatives assessment frameworks: research needs for the informed substitution of hazardous chemicals. Environ Health Perspect 124:265–280; http://dx.doi.org/10.1289/ehp.1409581

The Sustainability Solutions Agenda

Progress toward a more sustainable society is usually described in a “knowledge-first” framework, where science characterizes a problem in terms of its causes and mechanisms as a basis for subsequent action. Here we present a different approach—A Sustainability Solutions Agenda (SSA)—which seeks from the outset to identify the possible pathways to solutions. SSA focuses on uncovering paths to sustainability by improving current technological practice, and applying existing knowledge to identify and evaluate technological alternatives. SSA allows people and organizations to transition toward greater sustainability without sacrificing essential technological functions, and therefore does not threaten the interests that depend on those functions. Whereas knowledge-first approaches view scientific information as sufficient to convince people to take the right actions, even if those actions are perceived as against their immediate interests, SSA allows values to evolve toward greater attention to sustainability as a result of the positive experience of solving a problem.

The precautionary principle and democratizing expertise: A US perspective

Democratizing expertise carries many implications for application of the precautionary principle. It can extend the amount and types of information incorporated into decisions, empower citizens, and ensure that experts alone are not charged with making value-laden decisions. It can also expose uncertainties in science and decision-making, and bring forth unrecognized alternative solutions to problems. In this article, we outline the implications of democratizing expertise on implementation of the precautionary principle in a US context, as well as barriers and opportunities. We argue that initiatives to democratize expertise and implement precaution in the United States will occur first at the local and regional level as a result of grassroots momentum for change. Copyright , Beech Tree Publishing.

Children's Environmental Health: A Case Study in Implementing the Precautionary Principle

Abstract The plausible threat to children from environmental exposures and uncertainty as to the magnitude and nature of potentially harmful effects provide a rationale for taking precautionary measures to prevent such exposures. The authors present principles for applying precaution to childrens environmental health, and policy tools for implementing them. A stronger focus on primary prevention and a better understanding of the risks are needed.