described three overlapping domains within the exposome: a general external environment including the urban environment, education, climate factors, social capital, stress, a specific external environment with specific contaminants, radiation, infections, lifestyle factors (e.g. tobacco, alcohol), diet, physical activity, etc. an internal environment to include internal biological factors such as metabolic factors, hormones, gut microflora, inflammation, oxidative stress. In late 2013, this definition was explained in greater depth in the first book on the exposome. In 2014, the same author revised the definition to include the body's response with its endogenous metabolic processes which alter the processing of chemicals. More recently, evidenced by metabolic exposures in and around the time of pregnancy, the maternal metabolic exposome includes exposures such as maternal obesity/overweight and diabetes, and malnutrition, including high fat/high calorie diets, which are associated with poor fetal, infant and child growth, and increased incidence of obesity and other metabolic disorders in later life. Measurement For complex disorders, specific genetic causes appear to account for only 10-30% of the disease incidence, but there has been no standard or systematic way to measure the influence of environmental exposures. Some studies into the interaction of genetic and environmental factors in the incidence of diabetes have demonstrated that "environment-wide association studies" (EWAS, or exposome-wide association studies) may be feasible. However, it is not clear what data sets are most appropriate to represent the value of "E". Research initiatives As of 2016, it may not be possible to measure or model the full exposome, but several European projects have started to make first attempts. In 2012, the European Commission awarded two large grants to pursue exposome-related research. The HELIX project at the Barcelona-based Centre for Research in Environmental Epidemiology was launched around 2014, and aimed to develop an early-life exposome. A second project, Exposomics, based at Imperial College London, launched in 2012, aimed to use smartphones utilising GPS and environmental sensors to assess exposures. In late 2013, a major initiative called the "Health and Environment-Wide Associations based on Large Scale population Surveys" or HEALS, began. Touted as the largest environmental health-related study in Europe, HEALS proposes to adopt a paradigm defined by interactions between DNA sequence, epigenetic DNA modifications, gene expression, and environmental factors. In December 2011, the US National Academy of Sciences hosted a meeting entitled "Emerging Technologies for Measuring Individual Exposomes." A Centers for Disease Control and Prevention overview, "Exposome and Exposomics", outlines the