Multi-antibiotic resistant bacteria in landfill bioaerosols: Environmental conditions and biological risk assessment.

Landfills, as well as other waste management facilities are well-known bioaerosols sources. These places may foment antibiotic-resistance in bacterial bioaerosol (A.R.B.) due to inadequate pharmaceutical waste disposal. This issue may foster the necessity of using last-generation antibiotics with extra costs in the health care system, and deaths. The aim of this study was to reveal the multi-antibiotic resistant bacterial bioaerosol emitted by a sanitary landfill and the surrounding area. We evaluated the influence of environmental conditions in the occurrence of A.R.B. and biological risk assessment. Antibiotic resistance found in the bacteria aerosols was compared with the AWaRE consumption classification. We used the BIOGAVAL method to assess the workers' occupational exposure to antibiotic-resistant bacterial bioaerosols in the landfill. This study confirmed the multi-antibiotic resistant in bacterial bioaerosol in a landfill and in the surrounding area. Obtained mean concentrations of bacterial bioaerosols, as well as antibiotic-resistant in bacterial bioaerosol (A.R.B.), were high, especially for fine particles that may be a threat for human health. Results suggest the possible risk of antibiotic-resistance interchange between pathogenic and non-pathogenic species in the landfill facilities, thus promoting antibiotic multi-resistance genes spreading into the environment.

Assessment of the NO2 distribution and relationship with traffic load in the Caribbean coastal city.

NO2 ambient concentrations were measured in a coastal Caribbean city. Barranquilla is a Caribbean city located in the North of Colombia that has approximately 1.200.000 inhabitants and possesses a warm, humid climate. In order to obtain the concentration of the contaminant in an adequate resolution, 137 Passive diffusion tubes from Gradko© were installed. Tubes prepared with 20% Triethanolamine/De-ionised water were located at the roadside between 1 and 5 m from the kerb edge. The sampling period was two weeks, from 3/16/2019 to 3/30/2019. Samples were analyzed on the UV CARY1 spectrophotometer by Gradko©. Results showed an average of 19.92 ±â€¯11.50 µg/m3, with a maximum and minimum value of 70.27 and 0.57 µg/m3, respectively. NO2 correlation with load traffic load was higher than with maximum traffic. The expected results include the analysis of the areas of the city with high concentrations of this pollutant that exceed the limit values established by the WHO in six (6) points; however, they never exceed the local legal limit for annual exposure, which is significantly less restrictive. Overall, the multiregression analysis is a very effective method to enrich the understanding of NO2 distributions. It can provide scientific evidence for the relationship between NO2 and traffic, beneficial for developing the targeted policies and measures to reduce NO2 pollution levels in hot spots. This research may subsidize knowledge to serve as a tool for environmental and health authorities.