Thessaloniki – High concentrations of agricultural chemicals have been found in rainwater in three areas of Greece in measurements made by Thessaloniki University scientists. The experts are not yet in a position to assess the possible consequences on humans and their environment, according to findings presented at a recent meeting in Thessaloniki held by the Panhellenic Federation of Agronomists’ Associations at the Agrotica fair. Measurements over the past few years by the university’s Agricultural Pharmaceuticals Laboratory detected traces of chemicals in rainwater far higher than those in surface water. Results of surveys in the Axios River valley, Naoussa, Sindos, the Thessaly plain, the Arda River in the Evros prefecture and the rivers and lakes of northern Greece were presented by Professor Efthymia Papadopoulou-Mourkidou. Due to climatic conditions in Greece at the time of year in which agricultural chemicals are used, some of these do not end up in the soil or on plants but evaporate into the atmosphere and return to the earth in rainfall. In certain cases, air masses can transport traces of pesticides up to 100 kilometers (62 miles) from where they were used. In analyses of rain samples from the Axios catchment area, 47 active substances were found, out of the total 160 sought. «It is a very large number,» commented Papadopoulou-Mourkidou, «but only to be expected in Greek farming, given the wide variety of crops grown and the broad range of chemicals used, something which is not so common in central and northern Europe.» The most commonly found chemicals were Lindane and methyl parathion in 44 percent and 38 percent of samples, respectively. From the rainwater samples analyzed in the town of Naoussa, it was found that the greatest concentrations appeared in spring, when these chemicals were used. Thessaly and Evros Measurements on the plain of Thessaly and in the northern Evros prefecture were taken in 2001-2002. On the Thessaly plain, at least one active substance was found in about 80 percent of 250 rain samples, even in places where there was heavy rainfall last year and, in some areas, frost before the rain, and in others where the chemicals were not used. The highest concentrations of weed-killer were observed in spring rainfall. A similar situation was observed in Evros. Among the chemicals found were traces of DDT, banned for many years but still found where erosion has occurred. In one case, an active substance was found which was possibly imported from Turkey and which is used in rice fields. Concentrations of agricultural chemicals are far higher when there is less rain, observed Papadopoulou. On the basis of limits set by the European Union for the presence of chemical traces in water (0.1 microgram per liter), 73 percent of rainwater samples were found to be unsuitable for drinking. Their effects on the environment and on humans are unknown and hard to evaluate, since they have mingled to form a cocktail. Nowhere in the literature is there any information that could help contribute to drawing conclusions about having traces of so many chemicals in a particular environment. Such conclusions could be very important, for example, for the reservoirs in many areas, particularly the on islands, where there are severe water shortages. Most of these reservoirs were built for irrigation purposes but many are now used to store water supplies. Professor Papadopoulou-Mourkidou emphasized the need for a general inspection of rainwater during spring rains in many areas of the country. Samples of surface water in rivers and lakes in northern Greece showed that the heaviest concentrations of chemicals were in the Pineios, Loudias, Axios and Evros rivers, although the quality of water in the Ardas, Strymonas and Nestos rivers is relatively good. Traces, well below permissible levels however, were found in the Vegoritis, Zazari, Prespes, Petres and Doirani lakes.