Development of Testing Methods for Water Quality by Flow Analysis

"Flow analysis" is a generic term for continuous flow analysis (CFA) and flow injection analysis (FIA), which has been evolving into sequential injection analysis (SIA), stopped-in-loop flow analysis (SILFA), simultaneous injection effective mixing flow analysis (SIEMA) etc. Among them, CFA and FIA have been adapted into the Japanese Industrial Standard (JIS) K 0170 "Testing methods for water quality by flow analysis" in 2011. The JIS K 0170 consists of 9 parts, e.g. "part 1: Ammonium nitrogen", "part 3: Total nitrogen", "part 5: Phenol index". The Japanese Ministry of the Environment has adopted the JIS K 0170 as several national official methods in 2014. In addition, SIA has been finally adopted into the JIS K 0126 "General rules for flow analysis" in 2019, which eventually contains FIA, CFA and SIA. The recent movement toward standardization proves that flow analysis has been recognized as an analytical technique that can support industry. In the present paper, recent progress in the development of flow analysis methods (FIA, SIA, SILFA, SIEMA) for the determinations of several substances as environmental index in wastewater, drinking water and/or environmental water is reviewed.