Incidencia de las rutas del transporte público en la contaminación ambiental microbiana en los asideros de los buses urbanos de la ciudad de Ambato

Abstract

EXECUTIVE SUMMARY Urban transport units in suitable environmental conditions are an ideal site for the growth of bacteria. The research was based on the exploratory study with the validation of the problem of microbiological environmental contamination by qualitative and quantitative analysis of the inert surfaces of the buses that are in direct contact with the hands of the people. The methodology included the use of validated methods for the collection and analysis of samples, such as, swabbing of surfaces, culture of microorganisms in general and specific media, Microgen ID A +B and petrifilm plates for confirmation and quantification of a specific microorganism. The results showed that 9 of 10 units have some type of bacterium. Also, there is a prevalence of Staphylococcus aureus with 57.69%, then the quantitative analysis was performed, which showed that the most contaminated place of the bus is the vertical handle of the stop button, followed by the handle and the seat base (391.76, 333.46, 228.18 UFC/cm#), respectively. The incidence of variables was determined e.g. number of passengers per trip, opening or closing of windows, sampling site, sites where the transport unit crosses in increasing pollution levels, etc. The proposal determined that the following materials are not recommended for use in bus handles: stainless steel AISI 304, aluminum AA 6061, and steel with polymer. On the other hand, alloys with copper percentages greater than 65% are ideal for these applications.