W niniejszym artykule omówiono: - charakterystykę i podział środków ochrony roślin, - formę użytkowa, krążenie pestycydów w przyrodzie, ich występowanie w środowisku oraz źródła zanieczyszczeń pestycydowych.
EN
This article contains: - characteristics and division of pest control products, - form of use, pesticides’ circulation and occurrence in environment and sources of pesticides’ pollutants.
Investigated were the reactions that occur in the water between the free available chlorine (FAC) and uracil over the FAC/uracil ratio varying from 0.25 to 10 mol/mol and pH ranging from 6 to 9. The course of the reaction was related to the pH of the water, as well as to the presence of bromide, iodide and fluoride ions. It was found that when the FAC/uracil ratio was low, 5-chlorouracil was the only chlorination product. At FAC/uracil ratios greater than 10, dichlorouracil and nitrogen trichloride were present in the chlorination products, whereas chlorouracil was absent. In the presence of iodides and bromides in the investigated water, chlorination also accounted for the formation of 5-iodouracil and 5-bromouracil.
A method was developed, in which HANs in potable water are determined by solid phase microextraction (SPME). The analytical procedure is relatively quick and simple, yielding satisfactory recoveries, which range between 80% and 90%. The detection limit was evaluated as 0.04 to 0.08 mg/m[3]. The method is very sensitive with a relative standard deviation lower than 10%. A major advantage is its remarkable sensitivity, which makes it possible to limit the matrix effect. The analytical method proposed was made use of to determine HANs concentrations in the treated water from the Northern and Central Waterworks of Warsaw. HANs content was found to be insignificant (totalling up to 5 mg/m[3]). Determined were predominantly dichloroacetonitrile, bromochloroacetonitrile and dibromoacetonitrile. Brominated HANs detected in the water intake for the Northern Waterworks occurred at slightly lower concentrations.
Polychlorinated p-dibenzodioxines and polychhrinated dibenzofuranes (PCDD/F) belong to a widespread group of longlived chlorinated polycyclic aromatic compounds which are hazardous to the environment because of their toxic, mutagenic and carcinogenic character. Under natural conditions, PCDD/F originate during volcano eruption, forest fire and non-industrial low-temperature combustion. But these proces-ses contribute only slightly to the presence of PCDD/F in the natural environment. The main source of their origin is in the side reactions concomitant with the manufacture of chlorinated organic compounds. The largest portions of PCDD/F come from coal and liquid fuel combustion, from solid waste disposal and high-temperature industrial processes (metallurgy, cement manufacture, incineration of chemical wastes). PCDD/F enter the environment together with flue gases or solid wastes. In the 1940s, PCDD/F concentrations were low, but they increased rapidly in the next decades to reach a maximum in the 1980s. PCDD/F content in vegetation measured in 1980 was 7 to 8 times as high as in 1900. In rough estimates, the overall CDD/F deposition on land and oceans today amounts to 12,500 kg/a and 610 kg/a, respectively. Their lipophilic properties make PCDD/F accumulate in the adispose tissue. In the 1980, PCDD/F concentration in humans averaged 53.2 mgI-TEQ/kg. The largest PCDD/F portions (99.3%) are taken in by digestion (milk, 65.8%; meat, 26.1%; leaf-vegetables, 7.4%). The half life of PCDD/F in human organisms varies from 7 to 11 years. It has been anticipated that a harmless PCDD/F dose to humans ranges between 0.01 and 0.1 mgI-TEQ/kg day, the daily intake averaging 150pgI-TEQ/body.The carcinogenic index was found to be 1.5x10[5] ngI-TEQ/kg day. Modem solid waste incinerators meet the allowable PCDD/F concentration in the flue gas, which is below 0.1 ngI-TEQ/m3. Under such conditions, the carcinogenosis risk approaches 5x10[-8] incidents in a population with very high exposure to PCDD/F.
Dioxins are halogenated aromatic chemical compounds which have been the subject of much concern and debate over last years. A review of structures, chemical properties, sources, pollution and the occurrence in the marine environment is presented. Dioxins are two groups of tricyclic aromatic compounds polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and also related aromatic compounds; like mono- and non-orto-polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) (sometimes called "dioxin-like" compounds). Dioxins are formed in numerous sources like chemical, thermal, photochemical and enzymatic reactions, primarily in incineration and industrial processes. These very persistent halogenated aromatic compounds have been found throughout the world in practically all compartments of abiotic and biotic systems, including air, soil, water, fish, animals. A large number of these compounds have been observed to have toxicological effects at very low concentrations. PCDDs, PCDFs non-orto-PCBs have been found to have very similar biological and physicochemical properties. Consequently, sophisticated analytical methods should allow identifying and quantiffying multitude related compounds which are present in biological environmental matrix has been described. Nondestructive analytical method for suitable biological samples of marine environment. Many different compounds can be analyzed from the same sample using these methods, even if the amount of sample is limited.
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