USE OF BIOSOLIDS IN AGRICULTURE: CRITICAL ANALYSIS OF THE RESOLUTION CONAMA Nº 498/2020

Abstract

This document presents a critical-comparative analysis of the current Brazilian Resolution CONAMA nº 498/2020 in relation to the previous Resolution CONAMA nº 375/2006 and emblematic international regulatory documents, namely Norm 503 (USA) and Sludge Regulations (United Kingdom). The main changes in the Resolution CONAMA nº 498/2020 refers to a certain ‘flexibility’ regarding microbiological standards (laboratory monitoring and/or operational control), as well as uses and restrictions of biosolids Classes A and B. Additionally, more detailed information about sewage sludge treatment (production of biosolids) and operating parameters of Process to Significantly Reduce Pathogens (PRSP; Class B biosolids) and Process to Further Reduce Pathogens (PFRP; Class A biosolids), as well as the implementation of Classes I and II biosolids regarding chemical parameters. Despite the changes, Resolution CONAMA nº 498/2020 can be considered safe in terms of public health, essentially because it was, in theory, based on the concept of double barrier protection and the quantitative microbial risk assessment (QMRA) approach. Therefore, it is believed that the current legislation, along with public acts and policies as well as other legal instruments to encourage the use of biosolids in agriculture, can leverage the production and agricultural application of biosolids in Brazil. It is important to highlight, however, the relevance of future improvements (sewage sludge treatment; biosolids quality criteria; biosolid uses and restrictions) through research and scientific methodologies that prove and support decision-making processes.