RESUMO
A growing concern exists over water contamination by veterinary pharmaceuticals from small pig farms in Yucatan, Mexico, where the anaerobic digesters installed as the wastewater treatment system are not operated properly. Therefore, considerable interest exists to develop analytical methods to detect these compounds and characterize their fate in the environment. In this study, the detection of three antibiotics (enrofloxacin, oxytetracycline and sulfamethoxazole) and a ß-agonist (ractopamine) was carried out using fluorescence spectrophotometry, with a semi-quantitative approach and a low environmental impact. Wastewater samples from 10 pig farms were analyzed, detecting concentrations of approximately 0.043 µg mL-1 for enrofloxacin, 1.427 µg mL-1 for oxytetracycline, and 9.748 µg mL-1 for sulfamethoxazole. The detection of these pharmaceuticals in the effluents of treated wastewater from the biodigesters of the pig farms suggests the need to optimize the system and prevent the entry of these compounds into the environment.
Assuntos
Monitoramento Ambiental/métodos , Espectrometria de Fluorescência/métodos , Drogas Veterinárias/análise , Poluentes Químicos da Água/análise , Animais , Antibacterianos , Fazendas , Química Verde , México , Fenetilaminas , Suínos , Águas Residuárias/análise , Águas Residuárias/químicaRESUMO
The cattle production in Brazil has increased considerably in the last years, mainly due to the control of parasite infestation of the animals, which cause loss of productivity to the sector. Fluazuron is an active ingredient (a.i.) of the benzoylurea class used to control ticks in cattle. As this a.i. has been found unchanged in animal feces, which may present a risk to edaphic organisms, this study aimed to assess the effects of fluazuron on survival, reproduction, and behavior of the soil invertebrates Folsomia candida and Eisenia andrei, through ecotoxicological assays. We carried out bioassays in a tropical artificial soil (TAS) spiked with increasing doses of the insecticide. Earthworm mortality was found only at the highest tested fluazuron concentration (LOEC = 160 mg a.i. kg-1 dry soil and NOEC = 80 mg kg-1), while the reproduction of F. candida and E. andrei was reduced at lower fluazuron concentrations (EC50 = 4.48 mg kg-1 and EC50 = 20.8 mg kg-1, respectively). Avoidance behavior was detected for both species at lower concentrations than those that caused impacts on reproduction, indicating that the substance may affect the soil habitat function. Since the possible adverse effects of fluazuron on edaphic fauna are still unknown or neglected, this study also warns about the possible harmful effect of veterinary pharmaceutical products on edaphic fauna.
Assuntos
Artrópodes/fisiologia , Inseticidas/toxicidade , Oligoquetos/fisiologia , Compostos de Fenilureia/toxicidade , Poluentes do Solo/toxicidade , Animais , Bioensaio , Brasil , Ecotoxicologia , Reprodução , Solo , Testes de Toxicidade , Drogas VeterináriasRESUMO
The effects of pig manure, from diets incorporating veterinary pharmaceuticals, on survival and reproduction of Folsomia candida were evaluated. Manures derived from the following diets: corn and soymeal (CS); 85% CS diet+15% wheat meal (TR); CS diet+100ppm doxycycline+50ppm colistin+2500ppm Zn oxide (CSa); TR diet+100ppm doxycycline+50ppm colistin+2500ppm Zn oxide (TRa). Manures were tested in two subtropical soils representative of southern (Oxisol and Entisol). Despite the antibiotics no significant differences were found between the four manures within each soil. However, strong differences were found on the toxicity between soils. In Oxisol, LC50 values were around 100m(3)ha(-1), and EC50 values around 80m(3)ha(-1). In Entisol these were much lower, with LC50 values oscillating around 20m(3)ha(-1) and EC50 values between 10-15m(3)ha(-1). The observed toxicity on both soils was attributed to excess of nitrogen, Cu and Zn in the highest doses. The strong difference between soils could be explained by soil properties, namely CEC, organic matter, and clay contents that were lower in Entisol, indicating a poor ability to retain contaminants increasing their availability in soil. Results suggest that the application of these residues should be regulated not only using a volume-based criterion, but should incorporate data on soil properties, complemented by an ecotoxicological assessment.
Assuntos
Artrópodes/efeitos dos fármacos , Esterco , Poluentes do Solo/toxicidade , Drogas Veterinárias/toxicidade , Animais , Brasil , Cobre/toxicidade , Nitrogênio/toxicidade , Solo , Suínos , Zinco/toxicidadeRESUMO
An environmentally reliable analytical methodology was developed for direct quantification of tetracycline (TC) and oxytetracycline (OTC) using continuous flow injection analysis with spectrophotometric detection. The method is based on the diazo coupling reaction between the tetracyclines and diazotized sulfanilic acid in a basic medium, resulting in the formation of an intense orange azo compound that presents maximum absorption at 434 nm. Experimental design was used to optimize the analytical conditions. The proposed technique was validated over the concentration range of 1 to 40 µg mL(-1), and was successfully applied to samples of commercial veterinary pharmaceuticals. The detection (LOD) and quantification (LOQ) limits were 0.40 and 1.35 µg mL(-1), respectively. The samples were also analyzed by an HPLC method, and the results showed agreement with the proposed technique. The new flow injection method can be immediately used for quality control purposes in the pharmaceutical industry, facilitating monitoring in real time during the production processes of tetracycline formulations for veterinary use.