The Environment and Lifestyle Epidemiology Branch (ENV) is at the forefront of identifying modifiable cancer risk factors and protective factors to support the IARC vision of a world where fewer people develop cancer. Environmental and lifestyle factors are considered by IARC and ENV to comprise potentially carcinogenic substances in any medium – including soil, water, food, and air – that expose humans in their workplace, at home, and in the general environment. These factors include all types of radiation (ionizing, optical, and non-ionizing), as well as lifestyle factors such as habits or behaviours that are due to individual choice and to life circumstances within a socioeconomic and cultural context.
Environmental and lifestyle factors have already been established and identified as contributors to about 50% of the global cancer burden, and this group of factors are expected to be among the contributors to the remaining 50% of the burden, for which the causes are currently unknown. Knowledge of these factors is critical for primary prevention of cancer, because most of them are modifiable; exposure to modifiable factors can be totally avoided or at least reduced to less harmful levels. Such factors are also among the drivers of social disparities in the cancer burden, very often affecting the weakest and most vulnerable in societies, both within and across countries. There are an almost unlimited number of unanswered questions and, even more challenging, unanswered questions that have not yet been identified, on environment and lifestyle and cancer. In its strategy to set priorities, ENV is highly dedicated to IARC’s mission of cancer research that matters. This mission informs the selection of the Branch’s projects, which aim to generate a stronger and sustainable public health impact.
The Branch’s main programme of work centres around environmental, occupational, lifestyle, and radiation-related cancers. Over the course of the past seven years, ENV has developed two further strong lines of research: on cancer survival and on knowledge translation research. Specifically, for common cancer types that are less amenable to prevention but have the potential for good prognosis, ENV conducts research on cancer survival in low- and middle-income countries (LMICs). In the domain of knowledge translation, ENV conducts research into the implementation and dissemination of cancer prevention targeted to the general population, health professionals and promoters, and policy-makers. Each of these research programmes holds global relevance; thus, in ENV’s selection of priority study settings and populations, it focuses these endeavours on four main areas of research:
- research in settings where populations are exposed at high levels to putative or established carcinogens in the environment, in the workplace, or in common lifestyles;
- studies of common cancer types and of specific environmental, occupational, or lifestyle exposures that occur in settings where etiological research has been lacking;
- for cancer types with the potential for good prognosis, in settings where survival lags behind, studies evaluating the role of broader social and biological factors throughout the course of the disease and its prognosis;
- translating and catalysing knowledge on lifestyle, environmental, occupational, and radiation-related risk factors, and on screening and vaccination with the respective collaborators, into recommendations at the individual and population level.
For example, the Branch’s involvement often facilitates international collaboration, overcomes political barriers, and increases the local visibility of and trust in the work of local collaborators. ENV is also a strong leader at IARC in the initiation of new studies through assisting local collaborators with specific expertise, not only in ENV but also across IARC and across its wider international network.
With a strong focus on environmental – including occupational and radiation-related – and lifestyle risk factors, ENV fills a major research gap to further identify factors and to understand the cancer burden attributed to these factors. ENV has steered its research focus to LMICs in particular, a direction that is consistent with the Agency’s international remit and is warranted because in these settings, levels of environmental pollution are often higher and protection measures for workers and residents are less developed. Another focus of ENV is to identify and investigate previously unstudied lifestyle habits and exposures unique to LMICs and other settings that may affect carcinogenesis.
ENV also contributes extensively to IARC’s core and long-standing activities to invest in individual, infrastructure, and institutional capacity-building. This ethos is at the heart of how the Branch conducts research and is critical in ENV’s research in LMICs, so that the benefits of the research extend beyond the individual research project. ENV also plays a key role in the translation of research findings into applied cancer prevention. For example, research findings are used to inform the respective international and national authorities on worker protection, especially against radiation. More directly, ENV is coordinating cancer prevention research through the World Code Against Cancer initiative. ENV also chairs the newly established Cancer Prevention Europe platform, which had an influential role in shaping Europe’s Beating Cancer Plan and the European Union Cancer Mission.