Environmental Risks, Their Characteristics, and Sustainability Implications

Environmental risks are defined as risks with the potential to fundamentally disrupt the stability of the Earth's systems (IGBP 2012), while risk itself is defined as the combination of the probability of an event and its negative consequences (Nadim 2011). The destabilization of the Earth's systems could trigger environmental changes that would be deleterious or even catastrophic for human beings (Rockström et al. 2009). Such environmental risks encompass a wide range of areas such as climate change, water scarcity, deforestation, land degradation, biodiversity loss, ozone depletion, and chemical pollution. By their nature, environmental risks are characterized by (1) spatial propagation, (2) time-lag occurrence, (3) multiplier effects, (4) accumulation, and (5) irreversibility (Zhang et al. 2010). However, the most striking characteristic of environmental risks is their interconnectedness (IGBP 2012). For instance, excessive logging causes deforestation and destructs wild life habitats, thereby depleting biodiversity. Deforestation not only accelerates soil erosion but prompts the emission of greenhouse gases and their concentration in the atmosphere, thereby increasing the likelihood of climate change and destabilizing the water cycle. A negative change in one of the areas can aggravate another area and vice versa.

Risk management decisions often need to take into account the various trade-offs associated with environmental risks (Power and McCarty 2000). Environmental risks and their countermeasures always entail positive and negative environmental, economic, and social trade-offs (Table 1.1). For instance, rapid reforestation with a newly-introduced species of exotic fast-growing tree may be effective in increasing forest cover and sequestrating carbons, however it may also make the long-term integrity and autonomy of the forest ecosystem uncertain. It would reduce the space for endemic/indigenous tree species and wildlife habitats and would also hinder the access of local villagers to diverse forest resources such as leaves, fodder, fuel woods, and other non-timber products. It is therefore vital to ensure that reforestation would damage neither the environment nor people (Peskett and Todd 2013). We need to safeguard the overall environmental value of forest areas and the interests of local and indigenous people even as we pursue the goals of carbon sequestration, reduction of greenhouse gas emissions, and climate change mitigation (WRI 2012). Environmental risk trade-offs also need to take into account differing local conditions. DDT (dichloro-diphenyl-trichloroethane) and its application is a classic case often cited to describe environmental risk trade-offs and the complexity involved in assessing and making decisions about such trade-offs (Pfau 2011).

Table 1.1 Environmental risks and their trade-offs

Malaria is one of the most lethal diseases in the world. Although the total number of infections is declining gradually, it is estimated that in 2010 there were 219 million cases of infection, of which 79 % occurred in Africa. A total of 660,000 people were killed, with the death toll in Africa accounting for 90 % of these (WHO 2012). DDT is considered to be the most cost-effective insecticide for containing malaria (Pedercini et al. 2011). However, it is known that DDT may have a variety of human health effects, including reduced fertility, genital birth defects, breast cancer, diabetes, and damage to developing brains. In addition, its metabolite DDE (dichlorodiphenyl-dichloroethylene) can block male hormones (Cone 2009). DDT's stigma was made known to the world by Rachel Carson's “Silent Spring,” published in 1962 (Dugger 2006). DDT and DDE stay in the environment long-term and their bio-magnification threatens animals at higher trophic levels. Despite being banned in many countries during the 1970s on the grounds of its adverse effect on human health and ecosystems, DDT has been used particularly in developing countries to control malaria (Secretariat of the Stockholm Convention 2013). The Stockholm Convention on Persistent Organic Pollutants, adopted in 2001 and enforced in 2004, lists DDT as one of the “persistent organic pollutants” to be banned or regulated. On the other hand, in 2006, the World Health Organisation (WHO) reversed nearly 30 years of policies restraining the use of DDT and instead endorsed DDT use for indoor residual spraying (IRS) in epidemic areas as well as in areas with constant and high malaria transmission (WHO 2006; Boddy-Evans 2006).

As people have different perceptions of malaria risk, the use of DDT remained contentious, while associated measures to tackle malaria were carried out in ways that outraged communities. In one case in Uganda the government decided to start spraying, but did not give any advance warning to the communities, let alone consulting with them beforehand. Houses were sprayed even when people were not at home and food and cotton harvests had been left exposed. People were complaining that after the DDT spraying women suffered miscarriages and cattle died, but those who refused DDT spraying were imprisoned. Meanwhile, their cotton produce was rejected in the ecological market on the grounds of marginal DDT traces. It was rumored that corruption between the government and the chemical industry was involved, and that malaria risks had been exaggerated, and false claims made that alternatives to DDT were unavailable (Den Berg 2010). In fact, alternatives to DDT were promoted in a global program launched by the Global Environment Facility, WHO, and the United Nations Environment Programme in 2008. The program advocated integrated vector management including use of a mosquito-net, repellent, and mosquito coils (UNEP and WHO 2008).

The example of malaria risk management reveals the variability and complexity involved. Clearly, risk management must move beyond the assessment of a single risk to mobilize multi-disciplinary expertise in assessing multiple scientific and social risks (Pfau 2011) (Fig. 1.1). Moreover, stakeholder involvement is pivotal in developing and implementing long-term and self-reliant measures for managing risks and promoting sustainability. Public access to information, communication of risks, and stakeholder participation in decision-making are all fundamental to the process of determining countermeasures.

Fig. 1.1 Integrated approach to risk management (developed from Pfau 2011)

Effective measures for managing risks and promoting sustainability call for trans-disciplinary, multi-partnership, multi-dimensional research (Dedeurwaerdere 2013; Earth System Governance Project (ESGP) 2012). Spearheaded by the International Council for Science (ICSU) and others, the newly launched Future Earth sustainability research initiative is expected to play a key role in providing a reinforced, overarching framework for sustainability science (Yasunari 2013). The platform for enhancing the science-policy interface needs to be bolstered by building upon the prototype recently provided by the Intergovernmental Platform on Biodiversity and Ecosystem Services (Takeuchi 2013). Sciences that address risks and sustainability are changing to involve multiple actors in addressing issues from a trans-disciplinary perspective across a wider range of temporal and spatial scales (Benn et al. 2008). Universities must be pivotal players in transforming the platform of trans-disciplinary science to support risk management and the promotion of sustainability.