Planetary Health thematic web collection

Planetary health as a formal field of research has gained momentum since the landmark publication “Safeguarding human health in the Anthropocene epoch: report of The Rockefeller Foundation–Lancet Commission on planetary health”.¹ The basis for the Commission’s report will be familiar to most readers of Environmental Science: Processes & Impacts (ESPI), namely that human population and the activities that sustain civilization (providing sustenance, shelter, and energy) have expanded rapidly since the mid-20^th century, and these activities are so pervasive now that they drive global-scale changes to the Earth’s ecological, geological, and atmospheric processes. Perhaps the most prominent example is climate change forced by greenhouse gas emissions, but other aspects of the Earth system also are vulnerable to disruption by human activity, such as biogeochemical cycling of nutrients and regulation of stratospheric ozone. These changes in Earth systems are reflected in metrics such as the total flux of fixed nitrogen to the coastal zone and the percent of tropical forests that have been lost to harvest and land clearing, which when considered together are so prominent that it has become widely accepted that a new geological epoch, the Anthropocene, has replaced the Holocene. This reclassification reflects the profound influence that humans have had on the natural world^2,3 and foreshadows future challenges to planetary health.

At its core, planetary health postulates that human wellbeing—and its gradual improvement—have largely been sustained by the stable environmental conditions of the Holocene, and that progress in modern society has been enabled by the relatively unconstrained exploitation of Earth’s natural resources. However, mounting evidence suggests that Earth system responses are approaching thresholds that might become planetary-scale tipping points after which system functions will change dramatically.⁴ Crossing these thresholds could result in widespread collapse of the ecosystem services and environmental conditions that modern civilization requires. This alarming assessment of the state of the planet has attracted the attention of researchers from a wide range of disciplines, not only in climate science, but across the whole range of natural sciences and fields such as public health, engineering, economics, and political science. The goals of this research are unified under the planetary health theme, which aims to reframe well-known environmental concerns in the context of human health, environmental justice, and global health. A transdisciplinary perspective such as planetary health is needed to evaluate and prioritize societal changes that could reduce the risk of crossing planetary thresholds.

ESPI, like its predecessor the Journal of Environmental Monitoring, is a multidisciplinary publication that reports peer-reviewed research on environmental science, especially environmental chemistry, including natural atmospheric and biogeochemical processes, the effects of human activities on these processes, and the occurrence, risk, and control of environmental stressors such as chemical and microbial contaminants. Many of the journal’s articles address Earth system science or planetary-scale environmental processes that fit well under the theme planetary health research. It is useful to link these articles in a thematic web collection on planetary health for several reasons. First, it is likely that the authors of these publications did not know the term planetary health when they published their study, but in hindsight it clearly is applicable. Second, by highlighting the connections between diverse research topics from a new perspective we hope to encourage a more holistic appreciation of how the individual research papers featured here contribute to a common goal. Third, being one of the first collections of papers with a planetary health theme in an established environmental journal, we hope to help define the theme from an environmental chemistry perspective. Finally, we aimed to make this web collection a useful reference for those outside of the field of environmental science, for example global health advocates and social scientists, so they can easily access quality papers in planetary health without having to navigate the whole breadth of the ESPI research community.

To achieve these goals, we began by searching ESPI papers for keywords related to the nine planetary boundaries originally described in Rockström et al.⁴ and updated in Steffen et al.⁵ The boundaries are climate change, novel entities (formally chemical pollution), stratospheric ozone depletion, atmospheric aerosol loading, ocean acidification, biochemical flows of nitrogen and phosphorus, freshwater use, land system change, and biosphere integrity. The resulting list of roughly 70 papers included topics relevant to nearly all the planetary boundaries, the only exceptions being ocean acidification and ozone depletion. From this list we selected roughly 20 papers for scientific significance with direct application to some aspect of human health, environmental justice, or environmental stewardship. For example, a series of papers focused on the Ganges–Brahmaputra–Meghna delta system (Kay et al. 2015, Lázár et al. 2015, Whitehead et al. 2015, Jin et al. 2015; see Table 1) addresses the vulnerability of the region to sea level rise, climate change, nitrogen and phosphorus pollution, and land use change. Other papers clearly address the novel entities boundary, addressing important topics in chemical pollution for which very little is known regarding severity and effects on human health at the global scale (Sobek et al. 2016, McLachlan et al. 2018, Wannaz et al. 2018, Exley 2013; see Table 1). Still other papers featured here group into freshwater use with a focus on water quality (Malham et al. 2014, de la Cruz et al. 2013, Julian 2016; see Table 1).

Table 1 Selected papers included in the ESPI Planetary Health collection

Authors	Title	DOI
Kay et al.; 2015	Modelling the increased frequency of extreme sea levels in the Ganges–Brahmaputra–Meghna delta due to sea level rise and other effects of climate change	DOI: 10.1039/c4em00683f
Lázár et al.; 2015	Agricultural livelihoods in coastal Bangladesh under climate and environmental change – a model framework	DOI: 10.1039/c4em00600c
Whitehead et al.; 2015	Dynamic modeling of the Ganga river system: impacts of future climate and socio-economic change on flows and nitrogen fluxes in India and Bangladesh	DOI: 10.1039/c4em00616j
Jin et al.; 2015	Assessing the impacts of climate change and socio-economic changes on flow and phosphorus flux in the Ganga river system	DOI: 10.1039/c5em00092k
Sobek et al.; 2016	The dilemma in prioritizing chemicals for environmental analysis: known versus unknown hazards	DOI: 10.1039/c6em00163g
McLachlan et al.; 2018	Predicting global scale exposure of humans to PCB 153 from historical emissions	DOI: 10.1039/c8em00023a
Wannaz et al.; 2018	Source-to-exposure assessment with the Pangea multi-scale framework – case study in Australia	DOI: 10.1039/c7em00523g
Exley; 2013	Human exposure to aluminium	DOI: 10.1039/c3em00374d
Malham et al.; 2014	The interaction of human microbial pathogens, particulate material and nutrients in estuarine environments and their impacts on recreational and shellfish waters	DOI: 10.1039/c4em00031e
de la Cruz et al.; 2013	A review on cylindrospermopsin: the global occurrence, detection, toxicity and degradation of a potent cyanotoxin	DOI: 10.1039/c3em00353a
Julian; 2016	Environmental transmission of diarrheal pathogens in low and middle income countries	DOI: 10.1039/c6em00222f

We encourage readers to explore the full breadth of planetary health relevant papers in this web collection, and check back over time for new papers that are added. We hope that this web collection will serve as a hub of scientific publications that are relevant to planetary health much in the same way that the recently launched journals GeoHealth and The Lancet Planetary Health are intended to bring together diverse topics for the broad audience interested in planetary health.

References

1. S. Whitmee, A. Haines, C. Beyrer, F. Boltz, A. G. Capon, B. F. de Souza Dias, A. Ezeh, H. Frumkin, P. Gong and P. Head, et al., Safeguarding human health in the Anthropocene epoch: report of The Rockefeller Foundation–Lancet Commission on planetary health, Lancet, 2015, 386, 1973–2028.
2. P. J. Crutzen, Geology of mankind, Nature, 2002, 415, 23.
3. W. Steffen, W. Broadgate, L. Deutsch, O. Gaffney and C. Ludwig, The trajectory of the Anthropocene: the great acceleration, The Anthropocene Review, 2015, 2, 81–98.
4. J. Rockström, W. Steffen, K. Noone, Å. Persson, F. S. Chapin III, E. F. Lambin, T. M. Lenton, M. Scheffer, C. Folke and H. J. Schellnhuber, et al., A safe operating space for humanity, Nature, 2009, 461, 472–475.
5. W. Steffen, K. Richardson, J. Rockström, S. E. Cornell, I. Fetzer, E. M. Bennett, R. Biggs, S. R. Carpenter, W. de Vries and C. A. de Wit, et al., Planetary boundaries: Guiding human development on a changing planet, Science, 2015, 347, 1259855.

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