Strategy for Monitoring Organic Pollutants in Waste Water with Focus on Improved Sample Preparation

Abstract: Strategy and methodology is presented for the analysis of organic pollutants, with the purpose of evaluating treatment procedures for landfill leachate. Today, many investigations of treatment procedures are focusing on the measurement of water quality parameters such as chemical and biochemical oxygen demand, (COD and BOD), and total organic carbon, (TOC) when assessing the organic compounds in waste waters. These parameters give an unclear picture of the actual organic constituents. A developed analytical protocol, the Laqua protocol, covers several classes of organic contaminants, including both polar and non-polar markers, as well as inorganic parameters. As markers for polar compounds some phenols are selected and for non-polar markers polychlorinated biphenyls (PCB) and polybrominated diphenylethers (PBDE) are used. Unidentified markers are also followed to back up trends. The monitoring of individual compounds gave valuable information in understanding the processes in the treatment procedures. A toxicity test suitable for leachate water based on the crustacean Artemia Salina was also developed and included in the evaluation protocol. Combined with a simple fractionation of the leachate water, this test gave valuable information about the origin of the toxicity, which mainly originated from ammonium. The protocol was implemented and tested on a pilot plant for different treatment procedures in Kristianstad, Sweden. The bottle neck in the complicated analysis of organic pollutants is the expensive and resource demanding sample preparation step. In this thesis focus has been on developing automated, cost effective analytical procedures with sample preparation based on membrane technology. For PCBs, phthalates and organochlorine pesticides (OCP), automated procedures have been based on membrane-GC methodology, and for phenols an automated system, based on membrane-LC methodology, has been developed. A simple very efficient method based on disposable hollow fibre has been developed for the analysis of PBDE with GC-MS for final determination. All the developed methods dramatically decrease the time and effort spent on sample preparation, and demand only a very small fraction of organic solvents compared to conventional methods. The developed methods have very good performance, and as an example PCB extracted from 1 ml sample in 10 minutes gave detection limits of 2 - 3 ng/l, and relative standard deviations (RSD) at 0.1 µg/l of 1.6 - 5.0 % for all ten PCB congeners investigated.