Objective: Open surgical wound is prone to surgical site infection due to contamination of surrounding environment. Therefore, routine air sampling and culture of two operating rooms (OR) was performed from 2018 to 2023 to monitor and evaluate air quality and provide appropriate infection control measures. Method: 2 OR regularly performing prosthetic insertion were selected for routine air sampling every 6 months due to high risk of surgical infection associated with the procedure. Air sampling was performed by collecting 1000 litre of air over 10 minutes using air sampler (MAS-100 Eco, Merck). Collected air was cultured on blood agar plate and Sabourand dextrose agar for 30 days, and pathogen identification and quantification was performed upon positive culture result. This study employed a cut-off point of 17.6 colony forming unit (CFU) as specified by federal standards on biological particles published by National Aeronautics and Space Administration. Results: 12 air samplings was performed from 2018 to 2023. A single case of positive bacterial air culture was reported (20 CFU, coagulase-negative Staphylococcus). Infection control measures were provided upon reporting of positive bacterial air culture, including inspection of positive pressure ventilation system and high efficiency particulate air filter, disinfection of OR and the equipment, and more strict regulation of temperature and humidity. Air sampling was repeated after imposing the measures to evaluate their effectiveness. Cases of surgical site infection caused by the identified pathogen were monitored for 90 days, after which it was determined that there was no surgical site infection related to positive air culture. Conclusion: The six-year monitoring of OR air sampling confirmed that detection of positive air culture in routine sampling was not associated with surgical site infection. Based on this result, the hospital decided to conduct air sampling and culture only in outbreak of surgical site infection as part of epidemiologic evaluation.

Damage to non–dicamba resistant (non-DR) soybean [Glycine max (L.) Merr.] has been frequent in geographies where dicamba-resistant (DR) soybean and cotton (Gossypium hirsutum L.) have been grown and sprayed with the herbicide in recent years. Off-target movement field trials were conducted in northwest Arkansas to determine the relationship between dicamba concentration in the air and the extent of symptomology on non-DR soybean. Additionally, the frequency and concentration of dicamba in air samples at two locations in eastern Arkansas and environmental conditions that impacted the detection of the herbicide in air samples were evaluated. Treatment applications included dicamba at 560 g ae ha−1 (1X rate), glyphosate at 860 g ae ha−1, and particle drift retardant at 1% v/v applied to 0.37-ha fields with varying degrees of vegetation. The relationship between dicamba concentration in air samples and non-DR soybean response to the herbicide was more predictive with visible injury (generalized R2 = 0.82) than height reduction (generalized R2 = 0.43). The predicted dicamba air concentration resulting in 10% injury to soybean was 1.60 ng m−3 d−1 for a single exposure. The predicted concentration from a single exposure to dicamba resulting in a 10% height reduction was 3.78 ng m−3 d−1. Dicamba was frequently detected in eastern Arkansas, and daily detections above 1.60 ng m−3 occurred 17 times in the period sampled. The maximum concentration of dicamba recorded was 7.96 ng m−3 d−1, while dicamba concentrations at Marianna and Keiser, AR, were ≥1 ng m−3 d−1 in six samples collected in 2020 and 22 samples in 2021. Dicamba was detected consistently in air samples collected, indicating high usage in the region and the potential for soybean damage over an extended period. More research is needed to quantify the plant absorption rate of volatile dicamba and to evaluate the impact of multiple exposures of gaseous dicamba on non-targeted plant species.

To identify a cost-effective and practical method for detection of methicillin-resistant Staphylococcus aureus (MRSA) in pig herds, the relative sensitivity of four sample types: nasal swabs, ear-skin (skin behind the ears) swabs, environmental dust swabs and air was compared. Moreover, dependency of sensitivity on within-herd prevalence was estimated. spa-typing was applied in order to study strain diversity. The sensitivity of one air sample was equal to the sensitivity of ten pools of five nasal swabs and relatively independent of within-herd prevalence [predicted to be nearly perfect (99%) for within-herd prevalence ⩾25%]. The results indicate that taking swabs of skin behind the ears (ten pools of five) was even more sensitive than taking nasal swabs (ten pools of five) at the herd level and detected significantly more positive samples. spa types t011, t034 and t4208 were observed. In conclusion, MRSA detection by air sampling is easy to perform, reduces costs and analytical time compared to existing methods, and is recommended for initial testing of herds. Ear-skin swab sampling may be more sensitive for MRSA detection than air sampling or nasal swab sampling.