ABSTRACT
Rapid on-site measurements of arsenic (As) are essential for the timely remediation of As-contaminated groundwater for both municipal and emergency response applications. Current field tests either suffer from complicated end-user instructions (e.g., arsine gas generation tests) or a lack of accuracy and specificity (e.g., colourimetric strip tests). The FRED-As system combines genetically modified bacteria that relieve the burden of the end-user with an electrochemical measurement system that provides enhanced accuracy and signal intensity compared to traditional bacterial detection approaches. This system was tested against commercial field kits and gold-standard ICP-MS performed at an off-site third-party analytical laboratory. The FRED-As tests demonstrated excellent specificity and sensitivity down to <2 ppb As under lab conditions, as well as outperforming the commercial field tests. The FRED-As system was then validated in field trials with municipal and emergency response partners, providing on-site data within ±2 ppb of the off-site analytical laboratory.
