[Environmental surveillance of the steel industry by the people: the experiences of Piquiá de Baixo (MA) and Santa Cruz (RJ)].

Environmental surveillance by the people fosters the protagonism of individuals in a situation of environmental vulnerability to generate and evaluate data regarding the pollution to which they are exposed. The scope of this work was to analyze such experiences in two areas impacted by the steel industry: Santa Cruz/RJ and Piquiá de Baixo/MA. At these sites, community environmental monitoring (CEM) activities were conducted to measure 2.5 micrometer particulate matter (PM2.5) levels in the atmosphere, between November/2016 and July/2017. Such activities were conducted using a low-cost and easy-to-operate air quality monitor. Monthly averages of PM2.5 levels in Piquiá and Santa Cruz were high, depending on the period assessed, since they surpassed the annual average recommended by the World Health Organization (WHO) of 10 µg/m3, and, on several occasions, the recommended daily average of 25 µg/m3. The main idea of this monitoring proposal was to establish a process capable of presenting a counterpoint to official information on local atmospheric pollution scenarios, with the involvement of affected communities. The pollution data produced enable these communities to participate in public debates and decision-making processes in a more informed way.