BHIMS tool to aid risk assessment of exposure to multiple chemicals

Implementation of the basic hazard index screening for health risks associated with simultaneous exposure to multiple chemicals using a standardized target organ and systems framework

Evaluating the level of danger to human health from exposure to multiple chemicals in contaminated sites is a complex task. To address this difficulty, researchers have developed a new screening tool that can be incorporated into public health risk assessment, which may include polluted former industrial plants, waste dumps, or even land where pesticides have been used. This ‘hazard index’ approach indicates when risk to health is high, which organs are most affected, and where further evaluation should be conducted in the context of environmental or occupational exposure at such sites.

2017 Study Abstract

Environmental health risk assessments often involve assessing the potential health effects of exposure to multiple chemicals at once (i.e., complex mixtures). Because the possible number of chemical combinations is very large, few controlled in vivo toxicological studies with chemical mixtures are relevant or practical. In lieu of specific mixture toxicity data, the segregated hazard index (HI) approach has been used to determine whether simultaneous exposures may warrant further investigation due to their combined adverse effects. Each chemical is assigned to one or more target organs based on critical effects; HIs for each target organ are generated by summing the individual hazard quotients for each of the chemicals assigned to that organ or organ system. To conduct this phased risk assessment approach in a consistent manner, a comprehensive, systematized list of toxicity targets for implementing this approach is needed. We present a comprehensive and standardized list of toxicity target organs and systems (TTOS), with example data sets, for consistent implementation of the segregated HI method. This method is designed to facilitate the standardization of the widespread use of the basic segregated HI approach. The basic hazard index mixtures screening (BHIMS) tool allows for rapid identification of exposure concerns that may warrant further and more sophisticated assessment. Integr Environ Assess Manag 2017;13:852–860. Published 2017. This article is a US Government work and is in the public domain in the USA.

More Information
  • New hazard index tool to aid risk assessment of exposure to multiple chemicals, Science for Environment Policy, Issue 498, 6 December 2017.
  • Implementation of the basic hazard index screening for health risks associated with simultaneous exposure to multiple chemicals using a standardized target organ and systems framework, Society of Environmental Toxicology and Chemistry, March 2017.

Assessing the environmental safety of manufactured nanomaterials

Science for Environment Policy, IN-DEPTH REPORT, August 2017

Engineering at the nanoscale (one million to ten thousand times smaller than a millimetre; i.e. 1 to 100 nanometres) brings the promise of radical technological development — clean energy, highly effective medicines and space travel. But technology at this scale brings its own safety challenges.

This – Assessing the environmental safety of manufactured nanomaterialsIn-depth Report shows that, despite early fears, nano-sized particles are not inherently more toxic than larger particles; however, differences between them may be notable and new insights are still being provided by research.

The effects of nanoparticles on humans and the environment are complex and vary based on particle properties as well as chemical toxicity. This report brings together the latest science on environmental safety considerations specific to manufactured nanoscale materials, and the possible implications for policy and research.

  • Featured image Possible impacts of MNMs (manmade nanomaterials) on the aquatic environment (Geppert, 2015),, PDF page 54.
Related articles from Science for Environment Policy
  • Nanomaterial alternatives assessment: a powerful tool for identifying safer options, (June 2017).
  • Nanomaterial risk assessment frameworks and tools (March 2017).
  • Nanoparticles’ ecological risks: effects on soil microorganisms, (June 2016).
  • Collecting data to explore the ecological threat of (October 2015).

‘Emerging risks’ identified as first of four key stages in a risk cycle

Assigning risk ownership is not always simple, especially where the risk sits across different areas of responsibility

Risk governance tends to be adapted to routine risks, rather than emerging risks, which can evolve rapidly, affecting multiple stakeholders across geo-political boundaries. For example, unforeseen events such as the 2007 financial crisis and 2011 Fukushima disaster have highlighted how the world can quickly change without warning, with no set procedures in place for managing the effects.

Despite this awareness, the literature review found no unified, usable definition of emerging risks that could help policymakers with a framework for managing them. For example, in some definitions, an emergent risk is simply one that a stakeholder has failed to recognise so far, therefore preventing the calculation of probabilities and expected loss. Others emphasise that the risk will have an impact in the next one to five years, making them a priority for action over longer-term risks.

Some organisations highlight the dynamic nature of a risk portfolio, due to new technology, processes, discoveries or behaviours. For example, the European Food and Safety Agency (EFSA) connects emerging risks to newly identified hazards or increased exposure to known hazards. Uncertainty and magnitude of consequences also feature in definitions, yet these can also be associated with risks that are not emerging — thus they are not unique characteristics.

Instead of a type of risk, the study proposes that emerging risks in fact describe a stage in the risk cycle prior to full recognition at the scientific or societal level; at some point, every risk has been ‘emerging’. To deal with the real and socially constructed challenges posed by emerging risks — to mitigate or prevent their consequences — policymakers need to develop capabilities in signal detection and foresight.

The path of risk emergence can go through one or all of three states before reaching full emergence:

  • Ontological
    when combinations of activities and stakes (societal values) with potentially negative outcomes are modified, or when new combinations occur. These risks can be totally hidden from human perception (‘unknown unknowns’) until a change occurs. For example, asbestos has been used for at least 2 000 years, but the first death related to it was only officially recorded in 1906.
  • Epistemological
    when science highlights that an activity poses a threat, although the risk is uncertain and long-term studies are needed to gather evidence of the risk. For example, scientific literature recognises the risk of cancer from exposure to electromagnetic fields, but the extent of this risk is subject to conflicting evidence and only acknowledged by the World Health Organization as a possible carcinogen.
  • Societal
    where a risk is officially recognised, as well as the necessity for dedicated policies, responsibilities and acceptability levels. This stage does not necessarily follow ontological or epistemological emergence, but can be the result of social pressure or the application of the precautionary principle. For example, following the latter, France banned the endocrine disruptor Bisphenol A in 2012, although the EFSA states that exposure levels do not present a health risk.
  • Fully emerged
    where both scientific communities and policymakers agree there is a need to deploy appropriate risk policies, and scientific evidence continues to confirm the need to take action. The researcher argues that public debate on risks in the societal state are not necessarily influenced by scientific knowledge, but ‘fully emerged risks’, e.g. climate change, are confirmed by scientific evidence.

Risk ownership is highlighted at both the epistemological and societal stages. Insurance contracts and court decisions can set precedents with regards to responsibility, even where risks are scientifically controversial. For example, a French court awarded damages to a victim of electro hypersensitivity syndrome in 2015, for the first time. This sends a clear signal that there is a need for regulators and stakeholders to adopt a position on emerging risks even at the scientifically controversial stage. To base governance on scientific evidence, policymakers should make decisions on who holds responsibility for the risks related to novel activities and substances, e.g. nanoparticles, before the debate reaches the societal stage.

This approach invites policymakers to focus on risks at the ontological and epistemological stage in order to manage outcomes. Successfully detecting and interpreting early signals of change can even prevent negative effects of hidden risks. Moreover, the development of foresight capabilities can provide valuable analysis of risks and opportunities that may appear in the future. Both these techniques are fundamental for policymakers when defining the appropriate strategies for managing emerging risks.

Assigning risk ownership is not always simple, especially where the risk sits across different areas of responsibility. With such risks, when no single entity is officially in charge, the risk can be ‘orphaned’, resulting in no action. Governing the risks of global warming and other cross-boundary environmental issues requires going beyond national governance structures. For policymakers, this means long-term planning, co-ordination and collaboration across managerial levels.

Sources and More Information
  • (Re) Defining Emerging Risks, wiley online library, DOI: 10.1111/risa.12759, 2017-03-21.
  • ‘Emerging risks’ identified as first of four key stages in a risk cycle, Science for Environment Policy, Issue 495, 14 September 2017.
  • Featured image credit cerasis.

(Re) Defining Emerging Risks

‘Emerging risks’ identified as first of four key stages in a risk cycle

The phrase ‘emerging risk’ has been widely used in scientific and business communities, but without consensus on how to define and govern such a risk. A new study proposes that risk emergence goes through four states, from ‘unknown unknowns’ to risks that are fully in the public domain. Understanding emergence as a process can help decision makers detect and manage risks on the basis of scientific evidence.

Study Abstract

The concept of emergence in risk management can be seen as a revealing symptom of the increasing need for organizations to update their portfolio of risks and opportunities in a rapidly changing and highly competitive environment. Accordingly, the concept of emerging risks has been widely discussed in both scientific and business communities, with, however, a lack of agreement as to whether we should distinguish these risks from others and, if so, what should be the adopted approach for their governance. After reviewing a large set of definitions and conceptions of emerging risks, this article aims at exploring the existence of distinctive features allowing the characterization of a risk as emerging or not. First, we will demonstrate that the features used in the various definitions are ineffective to achieve this distinction. Furthermore, we will argue that all events and consequences associated with risks are or have been states of nature that emerged from complex interactions involving combinations of hazardous activities and stakes. Accordingly, emerging risks are no longer a specific category of risks; they are rather an early step in every risk life cycle that deserves specific governance approaches.

Sources and More Information
  • (Re) Defining Emerging Risks, wiley online library, DOI: 10.1111/risa.12759, 2017-03-21.
  • ‘Emerging risks’ identified as first of four key stages in a risk cycle, Science for Environment Policy, Issue 495, 14 September 2017.
  • Featured image credit insurancejournal.