Aggregate Organic Constituents

As water and wastewater are composed of mixtures of mineral and organic constituents under dissolved, colloidal, or suspended solid forms, the measurement of aggregate parameters is often more adapted than specific analysis for water quality characterisation or monitoring. In this context, biological oxygen demand (BOD5), chemical oxygen demand (COD), dissolved organic carbon (DOC), or total organic carbon (TOC) are important aggregate parameters linked to the presence of organic compounds in water. These parameters can be estimated by UV-visible spectrophotometry and several sensors or field spectrophotometers are now commercially available for online or in situ measurement. However, the most frequent application of UV spectrophotometry for water quality assessment in the last decade is the characterisation of dissolved organic matter in water bodies, parameter linked to the nature and fate of organic compounds mixture in water.