Environmental monitoring of biocides

In an environmental monitoring programme for biocides, we plan to collect surface-water, sediment and wastewater-effluent samples from 20/30 sites (rivers, lakes and agricultural drains) across a region over 24 months, with quarterly campaigns (≈ 4,000 samples total). Target compounds would include ~30/40 priority biocides (e.g. isothiazolinones, quats, triazines, fungicidal azoles) or biocides of your interest. Samples are pre-concentrated by SPE (typical enrichment ×500) and analysed by LC-MS/MS in MRM mode, with method LODs ≤0.5 ng/L and LOQs ≤1.5 ng/L in water, and 1–5 µg/kg in sediment. Data are stored in a relational database (one row = sample × analyte) with fields for concentration, QA flags, instrument batch, location, land use, flow rate, temperature, pH and DOC; we expect ≈ 160,000 concentration entries (4,000 samples × 40 analytes), of which perhaps 20–40% will be censored (<LOQ). We have a patented AI software that enables this in a fast and efficient manner. To identify and quantify biocide metabolism in animals and plants within environmental monitoring, we would combine targeted and semi-targeted metabolite profiling with controlled exposure studies using proprietary software (MassMetasite). Representative organisms exposed in situ at environmentally relevant concentrations, are sampled over a time series (e.g. 0, 6, 24, 72 h, 7 d). Samples are extracted and analysed by LC-HRMS/MS using both a targeted list of known phase I/II metabolites and semi-target workflows (suspect screening based on predicted biotransformations by MassMetasite). Peak annotation uses exact mass, isotope pattern, MS/MS similarity and, where possible, comparison to authentic metabolite standards; Metabolic conversion is quantified via time-resolved mass balance. Parallel in vitro assays help confirm the enzymatic nature and pathways of transformation, and kinetic parameters from these tests can be linked back to field concentrations using simple PBK/BCF models.