Survey Experiment of Contamination Control with Field Sampling Protocols in Freshwater Ecology Studies

Abstract

Contamination control is a foundational pillar of modern freshwater ecology, particularly as analytical techniques advance to detect trace substances such as environmental DNA and microplastics. Despite the existence of rigorous laboratory standards, sample collection in the field remains highly vulnerable to human-mediated contamination and protocol drift. This study assesses the determinants of field sampling protocol compliance using a randomized survey experiment conducted with a diverse cohort of four hundred and fifty environmental scientists, field technicians, and academic researchers. By employing factorial vignettes, we systematically manipulated environmental stressors, time constraints, institutional oversight, and physical discomfort to observe their effects on self-reported compliance and contamination risk-recognition. The empirical findings reveal that adverse weather conditions and acute time pressure significantly increase the likelihood of protocol drift, with environmental factors having a compounding negative effect on compliance. Surprisingly, years of professional experience did not linearly correlate with higher compliance; instead, mid-career professionals exhibited the highest rates of protocol deviation, suggesting an overconfidence effect. Conversely, formal training in contamination control and the presence of active field supervisors significantly mitigated these risks. These results underscore the critical need to design field protocols that account for human cognitive limits and physical constraints. We propose institutionalizing simplified physical checklists, developing user-centered sampling equipment, and implementing mandatory peer-monitoring systems to safeguard data integrity in freshwater monitoring campaigns.