# Impact of the Technical Snow Production Process on Bacterial Community Composition, Antibacterial Resistance Genes, and Antibiotic Input—A Dual Effect of the Inevitable

## TL;DR

This study examines how technical snowmaking affects bacteria, antibiotic resistance genes, and antimicrobial levels in water and snow, revealing both positive and negative environmental impacts.

## Contribution

The study provides new insights into the dual environmental effects of technical snowmaking on bacterial communities and antibiotic resistance.

## Key findings

- Culturable bacteria and most antibiotic resistance genes decreased during the snowmaking process.
- Antimicrobial concentrations varied, with some agents like ofloxacin and erythromycin decreasing, while others like cefoxitin appeared only in technical snow.
- Snowmaking altered bacterial community composition and diversity, favoring bacteria that can survive freezing or antimicrobial exposure.

## Abstract

Although climate warming-induced snow cover reduction, as well as the development of ski tourism in hot and dry countries, is shifting industries toward the use of technical snowmaking, its use raises hydrological, health-related, and environmental concerns. This study was aimed at enhancing our current understanding of the impact of technical snowmaking on the environment and human health. Culturable bacteriological indicators of water quality (Escherichia coli, fecal enterococci, Salmonella, and Staphylococcus), the presence and concentration of antimicrobials, genes determining bacterial antibiotic resistance (ARGs), and next-generation sequencing-based bacterial community composition and diversity were examined from river water, technological reservoirs, and technical snow from five ski resorts. The number of culturable bacteria and prevalence of most ARGs decreased during snowmaking. The concentration of antimicrobial agents changed irregularly, e.g., ofloxacin and erythromycin dropped in the snowmaking process, while cefoxitin was quantified only in technical snow. The bacterial community composition and diversity were altered through the technical snowmaking process, resulting in the survivability of freezing temperatures or the presence of antimicrobial agents. Water storage in reservoirs prior to snowmaking allows us to reduce bacterial and ARG contaminants. Frequent and thorough cleaning of snowmaking devices may aid in reducing the negative impact snowmaking can have on the environment by reducing contaminant input and limiting the disturbance of the ecological balance.