Predição e priorização de antibióticos para estudos de remoção do meio aquoso empregando biocarvões ativados preparados a partir de resíduos de biomassas
Data
2024-05-27
Autores
Barros, Lucelia Alcantara 
Orientadores
Labuto, Geórgia Christina
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A segurança hídrica planetária tem sido impactada pela inserção de diversos tipos de poluentes emergentes (PE) em ambientes aquáticos. Dentre os PE, os fármacos são particularmente preocupantes devido aos efeitos deletérios à biota e à promoção de resistência antimicrobiana. Monitorar e remover tais poluentes do meio aquoso requer a definição de moléculas prioritárias, dada a complexidade e o alto custo dessas ações. Este estudo utilizou dados de comercialização de fármacos no estado de São Paulo em 2022 associados a dados de saneamento básico, farmacocinéticos e porcentagem de remoção em tratamento de esgoto obtidos pelo software de predição EPI SuiteTM (Estimation Program Interface), para predizer a massa de antibióticos passível de ser inserida no meio ambiente. Para priorização, utilizou-se o software de hierarquização ToxPiTM (Toxicological Priorization Index), definindo um conjunto de 10 antibióticos prioritários baseados em parâmetros para 4 categorias: Destino ambiental, Propriedades físico-químicas, Efeitos ecotoxicológicos e de Exposição (massa predita, PM). Uma vez que a PM está diretamente relacionada à ocorrência dos efeitos sobre os seres vivos, diferentes pesos foram atribuídos à categoria Exposição, para garantir a presença de antibióticos de maior PM no conjunto prioritário, sem ofuscar a contribuição dos demais parâmetros empregados. A correlação de postos de Spearman permitiu constatar ser possível definir um conjunto prioritário pela contribuição de todos os parâmetros empregados, mesmo aplicando diferentes pesos na categoria Exposição. Do conjunto priorizado, três antibióticos selecionados tiveram desenvolvimento e validação de método analítico usando cromatografia líquida com detector DAD (Diode Array Detector): amoxicilina (AMX), cefalexina (CEFA) e ciprofloxacino (CIPRO). O método cromatográfico foi utilizado em estudos de adsorção dos fármacos por biocarvões ativados, preparados a partir de resíduos de biomassas agroindustriais. Os melhores adsorventes para os antibióticos foram os biocarvões ativados C4 e C8, preparados, respectivamente, a partir biomassa de bagaço de cana-de-açúcar (SB) e resíduo de levedura (YW), ativados com CO2 e vapor de água a 800 °C. A cinética de adsorção foi descrita pelo modelo de pseudo primeira e segunda ordem para o C4 e os estudos de isoterma de adsorção competitiva demonstraram que a interação adsorvatos:adsorvente pode ser descrita pelo modelo de isoterma multicomponente de Langmuir-Freundlich. Pelos parâmetros de afinidade de adsorção (b) inferiu-se como ordem preferencial de remoção (CIPRO>CEFA>AMX), corroborando as respectivas porcentagens de adsorção obtidas em água deionizada 9,29±0,05, 8,8±0,4 e 7,6±0,6 mg/L (77±6, 88±4 e 92,9±0,5%). O C4 foi empregado em estudos de remoção competitiva dos antibióticos em água superficial fortificada, mantendo a mesma ordem de capacidade de adsorção. Entretanto, os coeficientes de variação demonstraram forte interferência da matriz sobre a interação adsorvatos:adsorvente, indicada pela redução das porcentagens de adsorção e pelos desvios padrão relativos obtidos para AMX, CEFA e CIPRO, que foram de 4,7±1,7, 5,4±2,2 e 7,6±1,7 mg/L (47±17, 54±22 e 76,05±16,55%), respectivamente.
Planetary water security has been impacted by the introduction of various types of emerging pollutants (EPs) into aquatic environments. Among these EPs, pharmaceuticals are particularly concerning due to their deleterious effects on biota and the promotion of antimicrobial resistance. Monitoring and removing such pollutants from aquatic environments require the identification of priority molecules, given the complexity and high cost of these actions. This study utilized pharmaceutical sales data from the state of São Paulo in 2022, combined with basic sanitation data, pharmacokinetics, and sewage treatment removal percentages obtained using the prediction software EPI SuiteTM (Estimation Program Interface), to predict the mass of antibiotics likely to be introduced into the environment. For prioritization, the ToxPiTM (Toxicological Priorization Index) software was used, defining a set of 10 priority antibiotics based on parameters in four categories: Environmental Fate, Physicochemical Properties, Ecotoxicological Effects, and Exposure (predicted mass, PM). Since PM is directly related to the occurrence of effects on living organisms, different weights were assigned to the Exposure category to ensure the inclusion of antibiotics with higher PM in the priority set, without overshadowing the contribution of the other parameters used. Spearman's rank correlation showed that it was possible to define a priority set by the contribution of all parameters used, even when applying different weights to the Exposure category. From the prioritized set, three antibiotics were selected for which analytical methods using liquid chromatography with a DAD detector (Diode Array Detector) were developed and validated: amoxicillin (AMX), cephalexin (CEFA), and ciprofloxacin (CIPRO). The chromatographic method was used in studies of drug adsorption by activated biochars, prepared from agro-industrial biomass residues. The best adsorbents for the antibiotics were the activated biochars C4 and C8, prepared respectively from sugarcane bagasse (SB) and yeast waste (YW), activated with CO2 and steam at 800 °C. The adsorption kinetics for C4 were described by the pseudo-first and second-order model, and the competitive adsorption isotherm studies demonstrated that the adsorbate:adsorbent interaction could be described by the Langmuir-Freundlich multicomponent isotherm model. The adsorption affinity parameters (b) indicated a preferential removal order (CIPRO>CEFA>AMX), corroborating the respective adsorption percentages obtained in deionized water 9.29±0.05, 8.8±0.4 e 7.6±0.6 mg/L (77±6, 88±4 e 92.9±0.5%). C4 was employed in competitive removal studies of the antibiotics in fortified surface water, maintaining the same adsorption capacity order. However, the coefficients of variation demonstrated a strong matrix interference on the adsorbate:adsorbent interaction, indicated by the reduction in adsorption percentages and the relative standard deviations obtained for AMX, CEFA, and CIPRO, which were 4.7±1.7, 5.4±2.2 e 7.6±1.7 mg/L (47±17, 54±22 e 76.05±16.55%), respectively.
Planetary water security has been impacted by the introduction of various types of emerging pollutants (EPs) into aquatic environments. Among these EPs, pharmaceuticals are particularly concerning due to their deleterious effects on biota and the promotion of antimicrobial resistance. Monitoring and removing such pollutants from aquatic environments require the identification of priority molecules, given the complexity and high cost of these actions. This study utilized pharmaceutical sales data from the state of São Paulo in 2022, combined with basic sanitation data, pharmacokinetics, and sewage treatment removal percentages obtained using the prediction software EPI SuiteTM (Estimation Program Interface), to predict the mass of antibiotics likely to be introduced into the environment. For prioritization, the ToxPiTM (Toxicological Priorization Index) software was used, defining a set of 10 priority antibiotics based on parameters in four categories: Environmental Fate, Physicochemical Properties, Ecotoxicological Effects, and Exposure (predicted mass, PM). Since PM is directly related to the occurrence of effects on living organisms, different weights were assigned to the Exposure category to ensure the inclusion of antibiotics with higher PM in the priority set, without overshadowing the contribution of the other parameters used. Spearman's rank correlation showed that it was possible to define a priority set by the contribution of all parameters used, even when applying different weights to the Exposure category. From the prioritized set, three antibiotics were selected for which analytical methods using liquid chromatography with a DAD detector (Diode Array Detector) were developed and validated: amoxicillin (AMX), cephalexin (CEFA), and ciprofloxacin (CIPRO). The chromatographic method was used in studies of drug adsorption by activated biochars, prepared from agro-industrial biomass residues. The best adsorbents for the antibiotics were the activated biochars C4 and C8, prepared respectively from sugarcane bagasse (SB) and yeast waste (YW), activated with CO2 and steam at 800 °C. The adsorption kinetics for C4 were described by the pseudo-first and second-order model, and the competitive adsorption isotherm studies demonstrated that the adsorbate:adsorbent interaction could be described by the Langmuir-Freundlich multicomponent isotherm model. The adsorption affinity parameters (b) indicated a preferential removal order (CIPRO>CEFA>AMX), corroborating the respective adsorption percentages obtained in deionized water 9.29±0.05, 8.8±0.4 e 7.6±0.6 mg/L (77±6, 88±4 e 92.9±0.5%). C4 was employed in competitive removal studies of the antibiotics in fortified surface water, maintaining the same adsorption capacity order. However, the coefficients of variation demonstrated a strong matrix interference on the adsorbate:adsorbent interaction, indicated by the reduction in adsorption percentages and the relative standard deviations obtained for AMX, CEFA, and CIPRO, which were 4.7±1.7, 5.4±2.2 e 7.6±1.7 mg/L (47±17, 54±22 e 76.05±16.55%), respectively.