Pires, Ana FilipaAguiar, FátimaRosa, NunoCano, Manuela2019-02-282019-02-282018-10-25http://hdl.handle.net/10400.18/6001Poor risk assessment is one of the emerging issues related with the occupational exposure to biological agents. The Directive 2000/54/EC lays down the principles for the management of biological risks, however, in order to protect workers, the state of knowledge on biohazards still needs improvement. Employers are responsible for ensuring the management of biological risks, but the correct approach is difficult due to the lack of information on the biological agents present in each workplace, lack of validation and harmonization of detection methods for those agents. In wastewater treatment plants the exposure to biological agents is indirect, as an unintended result of the work processes. Correct risk assessment, based on the nature, degree and duration of exposure, is necessary in order to lay down adequate measures to protect workers’ health. Due to the lack of adequate analytical methods and the variability of biological agents present in a wastewater, it is impossible to identify the whole spectrum. However, gathering all the available information on the potentially present agents (risk group) and data on exposure, is possible to assess the risk. Aiming to establish the risks associated with routine tasks in wastewater treatment plants, culturable microorganisms were collected using a MAS-100 impactor with Trypticase Soy Agar, MacConkey Agar and Malt Extract Agar as culture media for total bacteria, Gram-negative bacteria and fungi, respectively. As expected, the higher concentrations were obtain in the plant facilities were the wastewater is agitated (screening and aeration tank) and sludge areas. Once the assessment is complete, it is essential to adjust the control measures in order to minimize the health effects on workers.engOccupational ExposureBiological AgentsWastewater TreatmentÁgua e Soloconference object