Ecological Risk Assessment for the Recent Case of DDT Pollution in Lake Maggiore (Northern Italy)

Abstract

Contamination by DDT of industrial origin was detected in 1996 in Lake Maggiore (Northern Italy) causing concern for wildlife and human health. Starting from 1998 a monitoring programme involving different research laboratories was undertaken to establish the pollution level of the lake. In assessing the ecological risk to Lake Maggiore wildlife during this period, the present study integrates information provided by the Commission for the Protection of Italian and Swiss Waters with further analysis and ecotoxicological tests carried out on some autochthonous target species for this insecticide. Sediments collected at the end of 1997 in the most contaminated bay (total DDT 860.2 ng g −1 dry weight) caused a decrease in fertility and growth of benthic oligochaetes and chironomids, while the 48 h IC 50 for Daphnia galeata (0.76 µg L −1 , c.i. 0.43-1.34) was much higher than the DDT concentration in the lake water. The risk of acute effects on zooplankton should therefore be excluded, while transfer through the trophic web and bioconcentration in fish and fish-eating birds are the most adverse consequences of DDT contamination in Lake Maggiore.

The Dynamics of Macroinvertebrate Assemblages in Response to Environmental Change in Four Basins of the Etueffont Landfill Leachate (Belfort, France)

“…The number of species of Beatidae was lower in the polluted basins (B1 and B2) ( Table 2), whereas the density and relative (Fabela et al 2001;Bouallam and Nejmeddine 2001;Bettinetti et al 2005).…”

Ecological effects of multiple stressors on a deep lake (Lago Maggiore, Italy) integrating neo and palaeolimnological approaches

“…Detailed distribution maps for macro and trace elements have been drawn up based on the core data (Baudo et al 1981;Viel and Damiani 1985;Rossi et al 1993;Baudo et al 2002;Bettinetti et al 2005;Guzzella et al 2007) and the total burdens of metals and POPs in sediments have been esti- mated (Cenci et al 1991;Provini et al 1995;Guzzella, unpublished data). All work to date shows mercury (and other trace metals not shown) and DDT at highest concentrations in sediments deposited during northern Italy's industrial and economic boom of the 1960s (Fig.…”

Zooplankton as an early warning system of persistent organic pollutants contamination in a deep lake (lake Iseo, Northern Italy)

“…The zooplankton community, instead, seemed to be much more affected because it is mainly composed by herbivores. However, although heavily contaminated, zooplankton organisms may have not been subject to direct negative effects (Bettinetti et al, 2005). The general decrease in DDT levels measured in 2010 could probably depend on the diminishing loads of these contaminants accumulated in the past in the ice of glaciers; therefore a gradual depletion of the accumulated contaminants can be reasonably expected.…”