Polychlorobiphenyls and persistent organochlorine pesticides in sea water at the pg 1 −1 level. Sampling apparatus and analytical methodology

Abstract

A sampling apparatus has been constructed for the collection and filtration of up to 28 1 of water at sea. The apparatus has been designed to minimise possible contamination from both the sampling equipment and the ship's environment. The apparatus has been utilised in the analysis of chlorinated biphenyls (CBs), persistent organochlorine pesticides (OCs), and pentachlorophenol (PCP), in both the aqueous and particulate phases. The apparatus is suitable for collection of estuarine and coastal waters where the levels of dissolved CBs, OCs and PCP are above the limit of determination of 15 pg l −1. The efficiency of the recovery of these compounds and variance of the extraction and analysis have been estimated by analysis of filtered sea water spiked at a range of concentrations from pg l −1 ng l −1. Recoveries ranged from 66.5 to 97.3% with coefficients of variation for the complete method from 7.2 to 29.9%. The contribution of the extraction to the variance of the complete method has been estimated utilising on-going laboratory quality control data.