Pesticide contamination

The documented occurrence of pesticides in surface water is indicative that mnoff is an important pathway for transport of pesticide away from the site of appHcation. An estimated 160 t of atra2ine, 71 t of sima2ine, 56 t of metolachlor, and 18 t of alachlor enter the Gulf of Mexico from the Mississippi River annually as the result of mnoff (47). Field appHcation of pesticides inevitably leads to pesticide contamination of surface mnoff water unless mnoff does not occur while pesticide residues remain on the surface of the soil. The amount of pesticides transported in a field in mnoff varies from site to site. It is controUed by the timing of mnoff events, pesticide formulation, physical—chemical properties of the pesticide, and properties of the soil surface (48). Under worst-case conditions, 10% or more of the appHed pesticide can leave the edge of the field where it was appHed. 

McConnell R, Pacheco F, Wahlberg K, et al. 1999. Subclinical health effects of environmental pesticide contamination in a developing country Cholinesterase depression in children. Environ Res A81 87-91. 

Balinova AM, Mondesky M. 1999. Pesticide contamination ground and surface water in Bulgarian Danube Plain. J Environ Sci Health B 34(l) 33-46. 

Begum, S., Begum, Z., and Alam, M.S. (1992). Organochlorine pesticide contamination of rainwater, domestic tap-water and well-water of Karachi-City. Journal of the Chemical Society of Pakistan 14, 8-11. 

Newton, I. and Wyllie, I. (1992). Recovery of a sparrowhawk population in relation to declining pesticide contamination. Journal of Applied Ecology 29, 476 84. 

The bulk of this paper will be concerned with the prospects of Ji-nitroso compound formation in the environment, and with environmental behaviors of selected nitroso compounds, as best we can describe or predict them from experimental work completed thus far. Obviously, once in the environment, a compound will to a large extent be subject to the same conditions whether it was formed there or introduced as a pesticide contaminant, and in this manuscript no attempt to differentiate between the two modes of introduction has been made. Such distinctions could, however, influence the location of a compound in the environment—say on a plant or soil surface if sprayed with a pesticide, admixed with soil if transported by leaching, etc., and some of the experiments cited will have been conceived with one or the other of the introduction modes in mind. 

For the above reasons, EPA s Office of Pesticide Programs has proposed a policy on the procedures for regulating pesticides contaminated with N-nitroso compound 0. Comments from the public and involved parties were invited and will be considered when EPA is preparing its final policy on N-nitroso compounds in pesticides, later in 1981 or early 1982. It is the intent of this paper to discuss l) the proposed policy by EPA 0 the important issues raised during the public comment period and (3) suggest what the final policy might look like. 

EPA "Pesticides Contaminated with N-Nitroso Compounds, Proposed Policy", Fed. Reg., June 25, 1980, U285U. 

Lagadec AJM, DJ Miller, AV Lilke, SB Hawthorne (2000) Pilot-scale subcritical water remediation of polycyclic aromatic hydrocarbon- and pesticide-contaminated soil. Environ Sci Technol 34 1542-1548. 

Pesticides are used to control pests in agriculture and animal breeding. It has been known since the 1950 s that pesticide contamination occurs worldwide (e.g. DDT). 

S.Z. Cohen, S.M. Creeger, R.F. Carsel, and C.G. Enfield, Potential for pesticide contamination of ground water from agricultural uses, in Treatment and Disposal of Pesticide Wastes, ed. R.F. Krueger and J.N. Seiber, ACS Symposium Series No. 259, American Chemical Society, Washington, DC, Chapter 18, pp. 318-319 (1984). 

A system for monitoring and controlling pesticide contamination of the environment and, in particular, of the soil, began within the USSR State Committee for Hydrometeorology (Gosgidromet) only in 1974 [17]. In the beginning, they worked with only a very tiny number of the pesticides... 

Pesticide storehouses were examined in five regions of the Astrakhan Oblast because of the rise in the Caspian sea level and the possibility of flooding in 1993-95. Only eight of 39 storehouses were standard however, even they did not meet construction standards, and most were in terrible condition. Residual pesticides contaminated the land surrounding many of these storehouses. In the Volodarsk Region, the maximal values for contamination were atrazine at 1330 times MPC DDT at 53 times MPC, methyl parathion at 1330 times MPC, trifluraline at 8000 times MPC, and phosalone at 107 times MPC. 

More than 80% of Moldavia s bodies of water in 1985-86 were dangerously contaminated with pesticides. The level of pesticide contamination was high in the main rivers of Ukraine the concentrations of DDT and its metabolites in the Dnepr reached 0.384 mkg/l [23]. 

Pesticides contaminate not only surface water, but also ground water and aquifers. By 1990 in the USSR, 15% of all pesticides used were detected in underground water [29]. Pesticides were detected in 86% of samples of underground water in Ukraine in 1986-87 (including DDT and its metabolites, HCH, dimethoate, phosalone, methyl parathion, malathion, trichlorfon, simazin, atrazine, and prometrin). In actual fact, the number of pesticides was apparently larger, but the laboratory was able to determine the content of only 30 of the 200 pesticides used at that time in Ukraine [29]. In the 1960s, in the Tashkent and Andizhan oblasts of Uzbekistan, the methylmercaptophos content in the water of studied well shafts was, by clearly underestimated data, 0.03 mg/l (MPC was 0.01 mg/l), of DDT was 0.6 mg/l (MPC was 0.1 mg/ I), and of HCH was 0.41 mg/l (MPC was 0.02 mg/l) [A49]. 

An analysis of materials on human illness of those people living in zones with varying levels of pesticide contamination permitted us to establish a correlation between the illness and the level of pesticide contamination in elements of the outside environment. 

Blood was studied in a group of virtually healthy adolescents aged 14-17 from two localities in the Ukraine, where pesticide exposure differed by a factor of three, though the pesticide content in food products, drinking water, air and soil in the experimental zone was not higher than public health standards permitted. In Azerbaijan there was a difference of 100 times in the amounts of pesticides used in the experimental and control localities, while the pesticide contamination of elements of the environment and food products in the experimental zone was 2-50 times higher than acceptable levels [A97]. Table 3.6 shows the results. 

In the region with pesticide contamination where subjects contracted viral hepatitis A, the pre-jaundice period was 4.2 days (in the control area, 5.1), the jaundice period lasted 32 days (22.4 in the control area), the liver enlarged more than in the control area and took longer to return to normal size, there was a larger number of patients who also had an enlarged spleen, there was more frequent damage to the nervous and cardiovascular systems (1.5-2 times higher than in the control area), mixed syndrome was observed more often (45% of the time, compared to 12.6% in the control area), and the illness was more frequently serious. 

Inevitably, in the middle of the 1980s the issue of pesticides contaminating food products resurfaced. The organization of this process was initiated by a Resolution of the Council of Ministers of the USSR on April 2, 1984, On... 

Table 3.15 gives some idea of the trends in pesticide contamination of different food products. As should have been expected, fatty dairy products, Table 3.15. Residual Pesticides in agricultural and food products in the USSR exceeding MPLs in 1988-89 [3]...

The data in Table 4.4 show the result of global pesticide contamination. These pesticides were never used in the Arctic nevertheless, they were found in humans. It is notable that pesticide concentrations in human blood were several times higher (and in the case of befa-HCH, 17 times higher) in Russia than in Sweden and Norway. 

Background pesticide contamination of the natural environment affects most animal species, mainly influencing their behavior and physiology [1]. For example, white rats natural resistance to plague is weakened by even the smallest dose of warfarin (0.075 mg per individual over 24 days). There are many such examples [88]. 

Pesticides, and especially OCPs (DDT and its metabolytes, HCH isomers, aldrine, dieldrin, heptachlor, etc.), are seen everywhere in mammals. Table 4.7 gives data on the death of higher vertebrates from causes linked to agricultural production in the USSR. About 40% of the accidental deaths of animals, and about 80% of birds, are due to pesticides. It is difficult to evaluate how many mammals in the environment die from pesticide contamination, since sick and weakened individuals fall prey to predators [6]. 

For example, in Tajikistan in 1980, more than 10% of local fish species were threatened by extinction as a result of poisoned bodies of water [3]. In the Nizhegorodsk oblast, 21 of 57 fish species disappeared by 1980, mainly due to the effects of agricultural run-off. On average, about 30% of the cases of fish death in freshwater reservoirs in the central belt of Russia are due to pesticide contamination of those bodies of water [1]. 

We have never seriously evaluated how dangerous pesticide contamination in bodies of water is for hydro-organisms. Modern knowledge has led us to draw a very important conclusion background environmental concentrations of several pesticides have almost risen to a level that seriously affects several species viability. It seems that we are on the edge of a veritable pesticide catastrophe for hydro-organisms. 

Gonsalves CM, Esteves da Silva JCG, Alpendurada MF (2007) Evaluation of the pesticide contamination of groundwater sampled over two years from a vulnerable zone in Portugal. J Agric Food Chem 55 6227-6235... 

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