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Drinkable water supplied by aqueducts undergoes preliminar potabilization which, in Italy, is mainly accomplished by chlorine addition. The bactericidal action involved in this process is always accompanied by chlorination and oxidation of organic species (mainly humic and fulvic acids) naturally present in treated waters, so that many disinfection by-products (DBPs) are formed, such as trihalomethanes (THMs) and halo-acetic acids (HAA), which can represent a chemical risk for public health. The aim of this study was the monitoring of DBPs in drinking water disinfected by chlorination, supplied by four different aqueducts of Central Friuli (Italy). DBP evaluations were performed in water samples consisting of both input and output of disinfection plants. The results of analytical determinations were worked out to provide the THM and HAA parameters for disinfected waters, while in feeding waters the following different conventional parameters were adopted: (i) trihalomethanes formation potential (THMFP), (ii) halo-acetic acids formation potential (HAAFP) and (iii) UV absorbance at 254 nm (UV254). The quite moderate content of chlorinated products found in all samples considered highlighted the excellent quality of potabilized waters available in Central Friuli. Moreover, our results confirmed that the majority of DBPs formed when chlorine is used for water disinfection consists of THMs, while chlorites and chlorates prevailed when potabilization is accomplished by using chlorine dioxide. Finally, simple UV254 monitoring turned out to be a profitable approach for the determination of chlorinated by-products only when THMs prevail among DBPs.

Residues of organochlorine compounds in human fat, liver, brain, kidney, and spleen were determined by gas chromatography. All the samples were obtained from residents of Ferrara Province, Italy, of both sexes and of ages ranging from 1 to 80 years who had no special exposure to insecticides. The following compounds were found: p,p'-DDE, o,p'-DDT, p,p'-DDT, HEOD, and heptachlor epoxide. DDT and its derivatives was found more frequently and at higher concentrations than the other compounds; the average weighted percentage ratio of DDE (as DDT) to total equivalent DDT in fat was 73.7%. The concentrations of residues in nonfatty tissues were considerably lower than in fatty tissue; in liver, and to a smaller extent in kidney, the average concentrations were higher than in other organs (brain and spleen). From comparisons of these results with those from other countries it appears that higher levels of chlorinated compounds are generally present in the Ferrara population.