Presencia de formas parasitarias de importancia zoonótica en arena de playas que inciden en el Parque Nacional Sistema Arrecifal Veracruzano

Background. The Veracruz coastal zone in Mexico has a vast coastline where different tourist (use of beaches), economic (urban-port, commercial, and gastronomic), social, cultural, and sports activities are carried out. In Mexico, the only regulation that refers to the quality of beaches is NMX-AA-120-SCFI-2016, in which the absence of fecal matter is determined as an indicator of its sanitary quality. However, the inadequate management of fecal material in recreational beaches compromises public health and contributes to water and sand quality deterioration. Objective. To evaluate the presence of parasitic forms of zoonotic importance in the sand of the beaches of the Veracruz-Boca del Río metropolitan area that affect the Veracruz Reef System National Park. Methods. A total of 100 samples of beach sand and 19 samples of fecal matter were taken in the period from June to October 2021. The analyzes were carried out at the Boca del Río Technological Institute/Aquatic Resources Research Laboratory by the Willis flotation technique and cup sedimentation. The presence of helminths was identified and quantified as bioindicators of fecal matter contamination. Results. Of the sand samples, 28 % were positive for parasitic forms with a recovery of 112 parasitic forms, of which 67.85 % correspond to parasites of the genus Strongyloides sp. and Hookworms. 32.35 % corresponds to non-pathogenic parasites for humans. Of the fecal matter samples collected, only 42.1 % showed positivity to the parasitized forms mentioned above. Conclusions. The presence of parasitic pathogenic forms in the sand samples indicates fecal contamination, which compromises the sanitary and environmental quality of the beach sand of the Veracruz-Boca del Río metropolitan area and the Veracruz Reef System National Park.Antecedentes. La zona costera de Veracruz cuenta con un amplio litoral en donde se realizan diferentes actividades turísticas (uso de playas), económicas (urbano-portuario, comercial y gastronómico), sociales, culturales y deportivas. En México, la única norma que hace referencia a la calidad de playas es la NMX-AA120-SCFI-2016, en la cual se determina la ausencia de materia fecal como indicador de su calidad sanitaria; sin embargo, el inadecuado manejo de la materia fecal canina en playas recreativas compromete la salud pública y contribuye al deterioro de la calidad del agua y arena. Objetivo. Evaluar la presencia de formas parasitarias de importancia zoonótica en arena de playas de la zona conurbada Veracruz-Boca del Río que inciden en el Parque Nacional Sistema Arrecifal Veracruzano. Métodos. Se tomaron en total 100 muestras de arena de playa y 19 muestras de materia fecal en el período comprendido de junio a octubre de 2021. Los análisis se realizaron en el Instituto Tecnológico de Boca del Río/Laboratorio de Investigación de Recursos Acuáticos, por la técnica de flotación de Willis y sedimentación en copa. Se identificó y cuantificó la presencia de helmintos como bioindicadores de contaminación por materia fecal. Resultados. 28 % de las muestras fueron positivas a formas parasitarias con una recuperación de 112 formas parasitarias, de las cuales el 67.74 % corresponden a parásitos del género Strongyloides sp. y anquilostomídeos. El 32.35 % corresponde a parásitos no patógenos para el hombre. De las muestras de materia fecal recolectadas solo 42.1 % mostraron positividad a formas parasitadas mencionadas anteriormente. Conclusiones. La presencia de formas parasitarias patógenas en las muestras de arena es un indicio de contaminación fecal que pone en riesgo la calidad sanitaria y ambiental de las playas arenosas de la zona conurbada Veracruz-Boca del Río y del Parque Nacional Sistema Arrecifal Veracruzano

Determining water quality of the lower basin of the Usumacinta River in Tabasco, Mexico: Determinación de la calidad del agua de la cuenca baja del Río Usumacinta en Tabasco, México

Objective: The objective of this study was to determine the water quality of the lower basin of the Usumacinta River, based on its physicochemical and microbiological characteristics. Design/methodology/approach: There were taken 11 monthly samplings of surface water during the rainy season, from June to December, 2017 and in the dry season, from April to May, 2018, in three different sites. The parameters of temperature, pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), total phosphorus (TP) and Nitrogen nitrate (N-nitrate) were evaluated. Significant statistical differences (p≤0.05) between seasons and between sites were determined. Results: The results obtained were compared with Mexican regulations and Ecological Criteria for water quality. The parameters such as EC, TDS, TSS and total phosphorus showed substantial differences among seasons. The temperature, pH, EC and N-nitrate, did not exceed the maximum permissible limits for the use of irrigation water, urban public use and protection of aquatic life. However, the presence of E. coli and total coliforms from 530 to> 24 196 MPN/100 ml was recorded throughout the study period. Findings/conclusions: Parameters under study did not show significant differences between sites. The rainy season had an important effect on the increase in concentrations of TSS, TP, N-nitrate and total coliforms. Also, that maximum concentrations were recorded during the study period in the sampling sites of Boca del Cerro (R1) and Puente Chablé (R2).Objective: To determine the water quality of the lower basin of the Usumacinta River (Tabasco, Mexico), based on its physicochemical and microbiological characteristics. Design/methodology/approach: There were taken 11 monthly samplings of surface water during the rainy season, from June to December, 2017 and in the dry season, from April to May, 2018, in three different sites. The parameters of temperature, Hydrogen potential (pH), Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), total phosphorus (TP) and Nitrogen nitrate (N-nitrate) were evaluated. Significant statistical differences (p ≤ 0.05) between seasons and among sites were determined. Results: The results obtained were compared with Mexican regulations and Ecological Criteria for water quality. The parameters such as EC, TDS, TSS and TP showed substantial differences among seasons. Values for temperature, pH, EC and N-nitrate, did not exceed the maximum permissible limits for the use of irrigation water, urban public use and protection of aquatic life. However, the presence of E. coli and total coliforms from 530 to > 24,196 MPN 100 mL-1 were recorded throughout the study period. Findings/conclusions: Parameters under study did not show significant differences among sites. The rainy season had an important effect on the increase in concentrations of TSS, TP, N-nitrate and total coliforms. Also, maximum concentrations were recorded during the study period in the sampling sites of Boca del Cerro (R1) and Puente Chablé (R2)