Systemic Exposure Monitoring

Exposure Verification · Exposure Verification overview

Systemic exposure monitoring uses whole-body biological matrices — urine, blood, exhaled air — to characterise the dose that has crossed the body's barriers and entered systemic circulation. It is the unifying measure across all uptake routes.

Why systemic measurement matters

Once a substance is systemic, it is available to all target organs. Two workers with identical air exposure but different RPE fit and dermal hygiene can have very different systemic doses. Systemic measurement evaluates the harm-relevant quantity — not the upstream hazard concentration.

Matrix choice

Urine for water-soluble metabolites (most VOCs, isocyanate diamines, urinary metals). Whole blood for protein-bound metals (Pb, Hg, Cd) and short-half-life parent compounds (CO as COHb). Exhaled air for very volatile parent compounds (benzene at ppb levels).

Integration with health surveillance

Systemic exposure monitoring sits alongside, not inside, COSHH regulation 11 health surveillance. Systemic dose is the exposure measurement; ill-health screening is the health surveillance question. The two are co-reported by the occupational health provider.