Biological research is now focusing more intensively on causal relationships between illnesses and environmental factors by assessing exposure levels.

Towards Personalised Predictive Medicine

Exposure to the environment – such factors as toxic chemical substances, ionising radiation, germs, microbes, parasites, etc – has an effect on our health throughout our lives. Harmful exposure may be linked to our homes or working environment and may involve such environmental pollution as general dirt, water contamination, air pollution, climate change impacts, or even noise. However, measuring these harmful factors is very complex and presents a number of challenges. The vast number of environmental components, variations in space and time, plus a lack of accurate measuring tools, all make it extremely difficult to obtain a precise analysis. A range of tools does already exist: mathematical models, questionnaire-based surveys and biomarkers based on measurements from blood, urine and hair. However, biomarkers which do not take into account all ‘exposures’ including lifestyle factors, cannot deliver a fully informed result. Now however, with increasing research into molecular epidemiology, new areas are opening up. The concept of the ‘exposome’, first put forward in a 2005 article by cancer epidemiologist Dr Christopher Wild, offers a more comprehensive approach to the effects on people’s health of exposure to chemical, physical and infectious agents. A number of research initiatives are up and running in Europe and the United States, among them the EU-supported, twelve-partner EXPOsOMICS* project, coordinated by researchers at Imperial College London, whose basic aim is to use smartphone technology to help assess environmental exposures.

Smartphone as monitoring tool

The ‘exposome’ discipline combines biological methods with tools from the bio-technology and bio-informatics fields, taking an epidemiological approach. The EXPOsOMICS consortium includes two small companies – one a specialist in sensors and development of smartphone technologies; the other specialising in integrating complex data. The tools developed under the project will collect exposure data – notably on air and water pollutants – for each person. This data can then be compared with biochemical and molecular changes taking place inside the body which may cause acute or chronic illness. The idea is to draw on the functionality available in smartphones, such as sensors and satellite-based geo-location, to build a system of ‘Personal Exposure Monitoring’ (PEM). Used in conjunction with existing measurements such as biomarkers, PEM will provide invaluable help to scientists seeking to estimate the role played by environmental factors in human illnesses.

Advances in public health

At the moment there are no precise measurements of links between environmental exposures and illness. It is therefore very difficult to forecast disease or deaths arising from such exposure. Moreover, in developed countries exposure occurs in small doses over time, which makes accurate analysis even more difficult. In addition, low exposure is often wrongly taken to mean low risk, which may lead to errors in the statistics, and the erroneous conclusion that there is no link between the environment and the illness being studied. This is where precise exposure analysis becomes an essential issue in the field of public health. An approach based on complementing personal genome data with the individual ‘exposome’ – encompassing the totality of human exposure to environmental (i.e. non-genetic) factors from conception onwards – allows us to envisage the possibility of a personalised preventative diagnosis.

*‘Enhanced exposure assessment and omic profiling for high priority environmental exposures in Europe’