NEWS

A glassful of carcinogenic agents

Drinking water that contains ever larger amounts of dangerous and carcinogenic nitrates. Water sources with arsenic in them. Water tables contaminated by fertilizers. Whole areas where tap water is not drinkable. Clearly, the whole issue of the stuff of life in Greece is set to become a central one in the not-so-distant future, especially at a time the European Union lowering permissible limits of contaminants in water and works to monitor and improve drinking water are still, in most cases, at a preliminary stage. It is not a complete exaggeration to say that sometimes the water people drink is literally sheer poison. In areas of the prefecture of Thessaloniki and northern Greece, large amounts of arsenic have been found in drinking water – admittedly in its natural, oxide form. But that does not mean it’s harmless. On the contrary, as Triandafyllos Albanis, assistant professor in the Chemistry Department of the University of Ioannina, said, it is a particularly toxic compound. According to a recent research note by the Quality of Life Directorate of the Prefecture of Thessaloniki, there is a serious problem with the quality of drinking water in the municipalities of Axios and Halastra due to the high arsenic content. In these areas, the water contains a number of contaminants, including, apart from arsenic, manganese and nitrates in amounts many times greater than permitted. Unfortunately, these areas are not exceptions. In a report on the program monitoring surface water quality in Macedonia and Thrace, which was produced by a research team headed by Efthymia Papadopoulou-Mourkidou of Thessaloniki University, a number of boreholes were found to have concentrations of arsenic much higher than the then (2002) permissible limits. Examples of «poisoned» boreholes are those of Baki in Orestiada, in Feres (up to 25 times higher than current permissible limits) and in Komotini. As of the beginning of this year, EU limits on arsenic levels are five times as stringent, with permissible concentrations lowered from 50 micrograms per liter to 10 micrograms per liter. But arsenic is not the whole story. According to research by Thessaloniki University’s pollution-monitoring laboratory, drinking water shows dangerous concentrations of carcinogenic nitrate ions in a number of areas. It is no coincidence that these areas all have intensive agriculture and the heavy use of agrochemicals, as is the case with the Axios River Valley and around the lakes of Volvi and Koroneia. The human factor Increasing contamination of ground and drinking water is to a large extent the result of human activity. A typical example is that of Ioannina. Since the protection zone around water sources has been encroached upon by every type of economic activity (from animal husbandry to industry), as well as by housing (with little forethought for the protection of the subsoil), the water table of the Ioannina plateau is dangerously polluted. Water pollution varies according to the crops in each area, due to the use of agrochemicals, which unfortunately lead to undesirable and long-term effects. Typical examples are those areas where citrus fruits are cultivated, such as in Arta, Argolida and Crete. Spraying with the herbicide Atrazol leaves behind traces of the carcinogenic substance atrazine. Concentrations at levels hazardous to human health have been found in the drinking water in these areas. The ground water in Attica is also heavily polluted. The water source management scheme carried out by the National Technical University of Athens (NTUA) for the Development Ministry, found concentrations of nitrates that are much higher than the highest permissible limits. Especially in urban areas that are heavily built up, or in areas with a dense concentration of industrial and agricultural activities, nitrates can reach 400-500 micrograms per liter. In some locations, water tables are polluted with waste and sewage, while in industrial areas that lack proper measures, high levels of heavy metals have been observed. It should be noted that the actual dangers posed by toxic substances are not fully known. Only last year, in August, did a Greek research team reveal the carcinogenic properties of atrazine. However, the problem is not the effect of each substance separately. Albanis explained that the simultaneous existence of many different toxic substances, even if each is below permissible limits, can cause toxicity in synergy. In other words, toxicity is multiplied due to the interactions between the various toxic substances. In these cases, toxicity can increase in geometric progression, which highlights how fluid legal limits actually are. Moreover, Albanis said, limits on agrochemicals are the same for each substance (1 microgram per liter), despite variable levels of toxicity. Nevertheless, there has been a steady trend, worldwide, to make these limits more stringent, which means that concentrations of pollutants need to be kept below present-day ones. Causes Natural causes for the existence of toxic substances in the ground of course exist. But economic development, and more specifically, intensive, chemical-based agriculture, has aggravated the problem over the last few years. Pollution from agrochemicals is exceptionally dangerous. It can reach great depths and penetrate the water table. For example, the Thessaloniki area has two water tables, the first 70 meters below the surface and the second 150 meters below the surface. A few years ago, pollution was found in the upper water table. Recently, traces of agrochemicals have appeared in the deeper water table. Moreover, agrochemicals lie around for a long time. Research in Denmark, mentioned by Papadopoulou-Mourkidou, has found such substances remain in the soil even three years after they have ceased to be used. But pollution has dramatically worsened because of delays in works to upgrade the water supply. In the shadow of the large highways and the Olympic Games, a number of dramatically necessary works have fallen by the wayside. Often, the delay is due to the pressure brought by those who object to changes in land use. Most municipalities, whose responsibility it is to carry out small-scale works, are literally stuck. It’s not by chance that those of Halastra and Axios mentioned above, whose water poses hazards to public health, have pleaded for more time, despite the fact that the prefecture’s department of health and safety has stressed the «imperative need for measures, given the degree to which permissible limits have been exceeded and the direct danger posed to human health.» Inspection of the quality of water is carried out by the National Laboratories Network, which belongs to the Ministry of the Environment, Planning and Public Works. But even at this level, fragmentation and division of power are not lacking. The network does not use the laboratories of the ministries of Agriculture and Development, nor university laboratories. The absence of a coordinating body to monitor water quality has led to a plethora of studies. Anyone wanting to act in a certain area would have to wade through them, a researcher pointed out. But while there are all together too many studies, there are far too few actual works.