A Holistic Passive Sampling Calibration For Alkylated Phenols
As part of our ongoing work studying the effects of operational discharges from the oil and gas industry in the North Sea we present results from a study to calibrate passive samplers for alkylated phenols (AP). The uptake characteristics of Semipermeable membrane devices (SPMD) and both types of commercially available polar organic chemical integrative sampler (POCIS) were determined for 30 AP. Samplers were exposed in a flow through system at concentrations of 100ng L-1 for a period of up to one month. The most polar AP were not accumulated in SPMDs in quantifiable amounts with significant uptake only occurring for compounds with log Kow > 3. Sampling rates ranged from 0.02 - 4 L-d, being highest for the most hydrophobic compounds. Sampling rates were < 1 L-d for POCIS with some considerably higher than those reported in the literature for other compounds. These sampling rates allow, for the first time, the calculation of time weighted water concentrations of these compounds. This will hopefully afford a more complete risk assessment of offshore discharges and also aid the study of the degradation products of alkylphenol ethoxylates from land based effluents. Results are discussed in terms of, physico-chemical properties of analytes, differences between sampler types, limitations of the experimental and analytical methods and the relevance to offshore monitoring.