RESUMEN
Pesticide use increases annually, and Brazil is the world's largest consumer. However, unlike the European Union (EU), there is no established limit value for pesticide mixtures in drinking water, and therefore the concentration of pesticides can reach 3354 times the EU limit. Thus, determining the risk of exposure to pesticide mixtures and their main metabolites is challenging and requires the use of alternative methods. In the present study, the Common Carp Brain (CCB) cell line was used to evaluate the in vitro toxicity of relevant pesticide mixtures (glyphosate, 2,4-D, atrazine, and mancozeb) and their main metabolites after 72 h of exposure. The tested concentrations were based on the Acceptable Daily Intake (ADI) defined by Brazilian legislation. The results showed that cells exposed to lower concentrations of the pesticide mixtures and the pesticide + metabolite mixtures were affected by a decrease in cell confluence, resazurin metabolism, and wound healing capacity. The IBR index showed that lower concentrations had more severe effects, suggesting the absence of safe concentrations of these pesticide and metabolite mixtures for the CCB cell line within the tested concentration range. These findings raise concerns about the effects of exposure to these substances on animal and human health.
RESUMEN
BACKGROUND: Silver nanoparticles (AgNP) are largely used in nanotechnological products, but the real risks for human and environment are still poorly understood if we consider the effects of mixtures of AgNP and environmental contaminants, such as non-essential metals. METHODS: The aim of the present study was to investigate the cytotoxicity and toxicological interaction of AgNP (1-4 nm, 0.36 and 3.6 µg mL-1) and cadmium (Cd, 1 and 10 µM) mixtures. The murine macrophage cell line RAW 264.7 was used as a model. RESULTS: Effects were observed after a few hours (4 h) on reactive oxygen species (ROS) and became more pronounced after 24 h-exposure. Cell death occurred by apoptosis, and loss of cell viability (24 h-exposure) was preceded by increases of ROS levels and DNA repair foci, but not of NO levels. Co-exposure potentiated some effects (decrease of cell viability and increase of ROS and NO levels), indicating toxicological interaction. CONCLUSION: These effects are important findings that must be better investigated, since the interaction of Cd with AgNP from nanoproducts may impair the function of macrophages and represent a health risk for humans.
Asunto(s)
Nanopartículas del Metal , Plata , Animales , Cadmio/toxicidad , Cloruro de Cadmio , Línea Celular , Supervivencia Celular , Humanos , Macrófagos , Nanopartículas del Metal/toxicidad , Ratones , Especies Reactivas de Oxígeno , Plata/toxicidadRESUMEN
Murine melanoma cells B16F1 were exposed to the flame retardant and wood preservative chemical 2,4,6-tribromophenol (TBP) during 24 and 48â¯h, at the concentrations found in human diet. TBP-exposed cells had increased MTT and Alamar blue® metabolism and ABCB5 mRNA levels (qPCR), but the cells had decreased proliferation (crystal violet assay), migration (scratch assay), and drug-effux transporters activity (rhodamine B efflux assay). Exposure to TBP did not affect the cell viability (neutral red and annexin V-PI assays), colony formation (colony number, clonogenic assay), and the levels of reactive oxygen species (DCF probe) or P53 mRNA (qPCR). The tested TBP concentrations had low toxicity to melanoma cells B16F1. However, dual effect on metastatic profile and chemoresistance suggests that the increase of ABCB5 positively modulates the cell chemoresistance, but decreases cell migration and proliferation. These findings may be explored in cancer therapy.