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This report describes the automation of colorimetric and fluorometric methods for the determination of low levels of formaldehyde and related compounds in drinking water, natural water and industrial effluents.the fluorometric method is based on the reaction of formaldehyde with 2, 4 -pentanedione and ammonia to form a fluorescent product. The colorimetric method utilizes chromotropic acid andThe fluorometric method was found to be much more specific than the colorimetric procedure and both methods are capable of determining formaldehyde down to 10 ugllitre at a rate of 10 -20 samples per hour.The results of a preliminary survey,concerning the occurrance of formaldehyde and related compounds in a wide variety of samples, ranging from drinking waters to industrial effluents, are also reported.The results indicate that considerable quantities of these conpounds are present in some waters receiving industrial wastes and these results 53Copyright01974 by Marcel Dekker, fnc. All Rights Reserved. Neither this work nor any part may b e reproddced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Downloaded by [University of Florida] at 17:03 10 June 2016 AFGHAN ET AL. also show that those samples which contain formaldehyde also indicate the presence of other carbonyl compounds.

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Can. J. Chem. 65, 1086Chem. 65, (1987.Analytical methodology for polychlorinated dioxins and furans (PCDDs and PCDFs) in environmental samples is not standardized. Many variations exist for the extraction, cleanup, quantitation, and confirmation of these compounds and reported detection limits and recoveries vary over several orders of magnitude. This paper describes research carried out at the Canada Centre for Inland Waters over the past seven or eight years to develop reliable methodology at ultratrace levels (10-'2-10-l 5 g/g) applicable to a wide range of environmental samples. Extraction techniques are described for biological tissue (fish, clams, leaches, eggs), fly ash, sediments, and water. Detailed cleanup procedures for the various matrices consist of most or all of the following: gel permeation chromatography liquid/liquid extraction with Na3P04, liquid/liquid extraction with H2S04, basic alumina chromatography, and carbon fibre chromatography. Preliminary screening of the cleaned extracts is achieved by gas chromatography equipped with a mass selective detector and positive identification by gas chromatography /mass spectrometry operated in electron impact and chemical ionization modes and with full scan and multiple ion detection. Custom software permitting the analysis of a wide range of compounds in a single run by gc/ms is reported. The presence of specific isomers of PCDDs and PCDFs is confirmed by high resolution gas chromatography /mass spectrometry. A radioimmunoassay screening procedure for PCDDs in environmental samples is also described. Les mtthodes d'analyse des dioxinnes et des furannes polychlorts (DPC et FPC) ne sont pas standardisees. Plusieurs variations existent pour l'extraction, le nettoyage, la quantification et la confirmation de la prtsence de ces composCs; de plus, les limites de dttection ainsi que les taux de rtcuptration rapportCs varient par plusieurs ordres de grandeur. Dans ce travail, on dtcrit les etudes effectukes au cours des 7 a 8 dernikres anntes au centre canadien des eaux inttrieures dans le but de dtvelopper une mtthodologie applicable a des niveaux d'ultratraces (lo-" h 10-g/g) et a un grand Cventail d'tchantillons prtlevts dans I'environnement. On dtcrit des techniques d'extraction pour des tissus biologiques (poissons, moules, eaux de lessivage et oeufs), des suies, des sediments et des tchantillons d'eau. Les diverses mCthodes dCtaillCes proposCes pour le nettoyage de diverses matrices comportent la plupart ou toutes les techniques suivantes: chromatographie par permCation de gel; extraction liquide/liquide avec du Na3P04; extraction liquide/liquide avec du &So4; chromatographie standards sur de l'alumine ou des fibres de charbon.On a effectut des essais prtliminaires sur des extraits IavCs en faisant appel a la chromatographie en phase gazeuse couplte h un dttecteur sClectif de masses; on a proctdC I'identification positive par chromatographie en phase gazeuse couplCe la spectromCtrie de masse, optrCe soit dans le mode d'impact Clectronique ou d'ionisat...

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