Chemicals are all around us
No matter where we live, we are surrounded by environmental substances. They are in the air we breathe, in the water we drink, in the food we eat, the products we use, and in the clothes we wear. Most of these substances occur naturally in the environment, but others are produced by men. Their presence in our bodies and the interactions they create remain, to a large extent, unknown.
What is Human Biomonitoring?
Human Biomonitoring (HBM) is a scientific technique that allows us to assess whether and to what extent these environmental substances have entered our bodies and how exposure may be changing over time. By measuring the concentration of natural and synthetic compounds in body fluids (blood, urine, and breast milk) or tissues (hair, nails, fat, and bone), biomonitoring can provide valuable information on environmental exposures and, in some cases, help, identifying potential health risks.
One of the strengths of HBM is that it can give very precise information on the total internal exposure of an individual at a given time, as it adds together exposure from multiple sources and routes (e.g. air, water, food). Yet, the risks these exposures may pose to human health, in which combination and at what levels, remain difficult to evaluate. A combination other methods is needed for this.
Collecting and analyzing samples
Human biomonitoring involves collecting samples from human volunteers – blood, hair, saliva or urine – and measuring the levels of indicators of chemicals uptake (known as biomarkers) that are of interest. The aim of HBM is to collect information on the exposure of a sample of the population which can then form the basis for further action at collective and at individual level.
Asking the right questions
HBM is much more than undertaking many chemical analyses. As well as quantitative chemical data, health professionals and policy-makers need to know where the chemicals come from, how they enter our bodies and what the possible health effects might be. For this, depending on the aims of the particular study, sample collection from volunteers is accompanied by carefully designed interviews and by questionnaires that investigate a range of factors that can reveal sources and pathways for exposure, such as: lifestyle (e.g. smoking, use of personal care products, living surroundings) and diet (food preferences) and other personal characteristics such as gender, age and medical history.
Creating a basis for policy-making
For a given chemical, HBM surveys can highlight spatial trends, help uncover cultural and lifestyle contributing factors, and indicate specific at-risk groups, such as given age cohorts. Surveys can also be repeated to reveal which chemical levels are increasing or decreasing with time and thus provide a focus for policy driven action or for policy evaluation. So far, HBM surveys have been conducted on a national or lower scale. And these have led to informed policy-making – which demonstrates the potential of HBM.
- In Germany, HBM has been used and applied to Health Policy for several purposes. Examples are the reduction of the risk associated with amalgam fillings, especially in children, and the decline of heavy metal contamination via drinking water by revision of the German Drinking Water Ordinance.
- In Spain, the program (2008-2010) BIOAMBIENT.ES represents the first Human Biomonitoring study at national level. The first results revealed that mercury is higher in the Spanish population and similar to the levels found in other European populations in which consumption of fish and other marine products is high.
- In Belgium, the Flanders biomonitoring program was part of a health survey network and was carried out in 8 different regions. The results of the last decade led the Public Waste Agency to boost the collection of pesticide waste after having observed elevated levels of banned pesticides in the blood of rural populations.
The vital importance of HBM lies in its preventative nature and its ability to track the results of policy initiatives. Daily, Europe’s citizens are exposed to a huge range of chemicals, both natural and man-made, which enter the human body. And although the amounts may be small, and their effects sometimes poorly understood, continuous exposure to a mix of these chemicals over long periods measured could have consequences for the health and well-being of individuals and society as a whole.
The challenge: A harmonised EU-lever HBM
National HBM surveys have shown that important information can be systematically collected on chemical exposure. When combined with information on possible sources, the way chemicals enter our bodies, and how they are metabolised this is vital information for the authorities concerned to take preventive actions on a scientific base. However, the differences in procedures used in national HBM surveys– for example, in the way samples are collected and stored, and the analytical techniques used - make it difficult to compare national data and aggregate information at European scale.
The twin projects COPHES/DEMOCOPHES aim to demonstrate that harmonised procedures will enhance the comparability of HBM surveys and are leading the creation of a European HBM infrastructure and, eventually, an EU-wide database. This will enable national authorities to draw on survey results done in other Member States with confidence, and use this science-based evidence to shape environmental health policy-making and refine national HBM surveys. Furthermore, common procedures will allow EU-wide HBM surveys to support the European Environment and Health Strategy and Action Plan. Comparable HBM surveys can also provide support to REACH that regulate the safety of chemicals in products put on EU markets, as well as to other risk assessment legislation concerning, for example, cosmetics, food safety, pesticides or biocides.