Chemical safety is recognized in Agenda 21(UNCED - Rio 92), as one of the most serious problems to be faced worldwide being a problem not just of governability, restricted more to the role of states and governments, but of governance at the national and international levels. It poses greater challenges for countries like Brazil where the issues of democracy, security, sustainability and equity, which are fundamental to governance, are merely incipient and still far from solved. Taking as references the analysis of four cases in the Brazilian context, we illustrate the situation from less densely populated areas (as in the cases of mercury use by gold miners in the Amazon and pesticides in agricultural producing areas), through medium-sized towns (as in the accident with cesium 137 in Goiania), to the major urban and industrial centers (as in the cases of lead from battery renovators and benzene in the oil and steel industries and oil refineries). What can be seen is a situation where problems connected with chemical safety have grown in intensity and extent far more than the capacity to deal with them. In industrializing countries, the formulation of chemical safety policies must take into account not only the complexity and uncertainties involved in understanding the problems, but also the aspects relating to the different modes and levels of vulnerability. This is necessary in order to attempt to build better contextualized and more participatory knowledge and decision-making processes at the local and global levels, which we take as basic prerequisites for governance.