Summary Due to the increasing use of electric and electronic components and devices, and their relatively short life cycle, electronic waste is steadily mounting. To deal with it, the numbers of companies specialized in electronic waste recycling (e-recycling) are on the rise in Québec, as they are in other parts of the world. These companies employ workers who dismantle devices in order to sort through the components that subsequently will be recovered or disposed of safely. However, these tasks can lead to workers becoming exposed to a mix of potentially toxic substances, including dust, metal and fire retardants. Some metals, such as arsenic, cadmium and nickel, are carcinogenic. In addition, cadmium, lead and mercury, as well as several bromated, organophosphate and chlorinated flame retardants, can also act on hormones and are regarded as endocrine disruptors. The objective of this research is to determine workers’ exposure to dust, metals and flame retardants in primary e-recycling companies in Québec and to assess the level of health risk that may arise from it. As part of a transversal study, personal air samples were taken from 85 employees at six electronic recycling companies during two complete work shifts, as well from 15 commercial recycling employees (comparison group). At the end of the shifts, urine and blood samples were also collected from these workers, who answered a short questionnaire about their lifestyles and sociodemographic status. Concentrations of 14 metals and 40 flame retardants were measured in the air samples, while concentrations of nine metals and 27 flame retardants were measured in biological fluids. Ten hormones were measured in the workers’ blood to assess their association with endocrine disruptor exposure levels. Finally, occupational health and safety practices were documented through structured interviews conducted with some 30 workers and managers. In electronic recycling companies, dust concentrations at workstations were, on average, between 4 to 14% of the exposure limit value of 10 mg/m3 in force in Québec. Dust exposure is mainly due to the resuspension of fairly large particles that had previously settled on the floor or work tables when electric or electronic waste is being dismantled, cleaned, thrown around or slammed down, or during the handling of bins or containers. Airborne dust concentration was associated with company size; larger companies with a greater production volume and a more rapid work pace had the highest concentrations. The most frequently detected metals in the air at e-recycling facilities were lead (73 to 100% of samples), cadmium (18 to 94%) and copper (50 to 94%). Airway exposure was partially reflected in the biological fluids of workers, where blood lead values in some workers were as high as half the biological exposure index in effect, and where cadmium was detected in the blood of 86 to 100% of the workers. Air sample analysis also revealed relatively high concentrations of flame retardants, with a higher concentration of decabromodiphenyl ether (BDE209) than all values published to date (geometric mean [GM]: 5100 ng/m3). Baling and dismantling tasks were associated with exposures averaging 1.4 to 2.2 times higher than supervisory tasks, respectively. Finally, blood concentrations of BDE209 (GM: 18 ng/g lipid) among electronic recycling workers were higher than those working in commercial recycling (GM: 1.7 ng/g lipid). The level of health risk associated with metal exposure in e-recycling showed a concomitant exposure to manganese, lead and mercury, indicating potential neurotoxic or nephrotoxic impairment for some workers. With respect to endocrine effects related to exposure to flame retardants and certain metals, a statistically significant decrease in free and total testosterone for a doubling of the concentration of tb-TPhP (a metabolite of organophosphate flame retardants) and a statistically significant increase in estradiol for a doubling of the concentration of o-iPr-DPhP (another metabolite of organophosphate flame retardants) was seen in male workers. Company size was the factor that most influenced workers’ exposure levels to dust, metals and flame retardants. In addition, the tasks of manual dismantling and baler operation exposed workers to a wider range of substances than supervision tasks. Workers and their managers were somewhat aware of occupational health and safety issues pertaining to e-recycling. However, preventive practices varied, depending on the companies’ social mission and recruitment strategy. In particular, the wearing and availability of personal protective equipment was often deficient, as was access to appropriate training upon job entry. Moreover, an often precarious employment relationship, inadequate support networks and material deprivation place most of these workers in a vulnerable position in terms of occupational health and safety. This report makes some recommendations about work conditions, the regulatory aspects of monitoring and research needs in the e-recycling sector. Efforts should be made to reduce employee exposure to airborne dust, both by implementing diligent cleaning procedures and adopting work practices that minimize its displacement, and by utilizing and correctly wearing respiratory protection devices. Furthermore, given the presence of lead in the air and the blood of several workers, annual biological monitoring should be implemented if it is not already in place.