Monitoring and risk assessment of contaminants in Southern Africa: Arusha in Tanzania as a model

The background of the project was increased modernization, urbanization and industrialization in Africa leading to increased pollution of the environment. Intensified farming can lead to increased use of pesticides and contaminate food products for local markets as well as for export. Contaminants distributed by industry, traffic, plastic, garbage and electric waste may contaminate soil, sediment, air, plants, animals and humans. Some contaminants have the ability to accumulate in the environment, have long degradation and can be stored in adipose tissue. Toxic effects include neurological disorders, skin lesions, birth defects, cancer development, hormonal disruption and reproductive problems. In general, there is limited knowledge about the occurrence of hazardous substances in developing countries, including Tanzania. The project hypothesis is that the presence of pollutants in Southern Africa may have adverse effects on human health and the environment. The main objective of the project is to identify the extent of the agricultural and industrial pollution in Arusha in northern Tanzania. Arusha is selected as model region because this region represents other agricultural and urban regions under development in southern Africa. The project is conducting a sociological study and characterize the pollution situation in various districts in Arusha with the intention of risk assessment of pollutants in this region. In autumn 2012, the farmers, agricultural advisors and general population were interviewed to uncover usage, attitudes and knowledge about pesticides. Meanwhile, the agricultural workers and first-time mothers were interviewed about eating habits, work and way of life. The project has collected food samples that include vegetables, milk, eggs, chickens, fish and human samples including blood from agricultural workers and breast milk, blood, placenta, umbilical blood and meconium from first-time mothers and their children. Preliminary results of analyses of foods and human samples indicate the presence of various pesticides, chlorinated hydrocarbons and brominated flame retardants in various concentrations. In some samples, concentrations of pesticides exceeded the EU permitted limit in foods (European Maximum Residue Levels (MRLs)). There were found relatively high levels of various pollutants in mothers and their children. The project revealed findings of substances which have been prohibited for decades. A database is created to collect project results. Research results will be disseminated to the community. The project will contribute expertise interchange between south and north and will transfer knowledge and technology to institutions in Tanzania. The results of a hazard and risk characterization of the research results have been and will be made available to various parts of society and will be available for international monitoring bodies (WHO/UNEP, Stockholm Convention).

In Africa rapid population growth, accompanied by intense urbanization, increase of industrial activities and a higher exploitation of cultivable land have led to a huge increase in the quantity of discharge of various types of environmental pollutants wh ich may adversely affect humans and animals. Of particular concern is the fact that uncontrolled discharge of potential harmful pollutants is still occurring due to low level of awareness of safe pollution handling, utilization and protection. Data to con duct risk assessment and management on pesticide pollution in humans, food and environment is not available. This integrated multidisciplinary project involving experience within epidemiology, social science and environmental toxicology is designed to a ddress the United Nations? Millennium Development Goal number 7 'Ensure Environmental Sustainability'. The main objective of this project is to reveal the status of agro- and industrial chemical contamination in Southern Africa as the bases for risk asses sment and management. To fulfil the aim, the project will use affordable and reliable tools for the detection, monitoring and reporting of contaminants in water, domestic animals, wildlife and humans in Eastern Africa and transfer the technologies and kno w-how to institutions in the South. The results will aid in the managements of hazardous chemicals on an international level. The project will develop important scientific network between relevant national, continental and global institutions, and enhance the knowledge base for achieving sustainable development in less developed countries as well as on a global level.