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Simazine groundwater

Atrazine and simazine arose principally as a result of their use in amenity situations but, since their ban for non-agriciiltiiral purposes, concentrations are generally declining. Fiowever, atrazine and simazine still have some agricultural uses (atrazine on maize and simazine on a wide range of crops), so the risk of pollution still exists when these pesticides are applied in either groundwater or surface water drinking water supply catchments. [Pg.49]

In several AT studies, pesticide levels in the Ebro were found to be high. Hildebrandt et al. [50] found a homogeneous contamination pattern from atrazine (and also from simazine from May 2000) in intensive Rioja cultivation areas throughout the Ebro. Nearer to the delta, Barata et al. [72] found high levels of bentazone, methyl-4-chlorophenoxyacetic acid, propanil, molinate and fenitrothion in water, while Kuster et al. [71] found low concentration levels of atrazine and simazine at the delta, but high levels of other pesticides used in rice cultivation. Importantly, Hildebrandt et al. [50] found that levels of pesticides in groundwater... [Pg.318]

Groundwater contamination by agrochemicals from non-point sources has been well documented in a number of countries [26-28, 30-32], The pesticides that have been detected in regional council groundwater surveys include 2,4-D, Amitrole, Picloram, Simazine and Atrazine [20]. [Pg.470]

Fig. 9a, b. Chromatograms obtained after pre-concentration of a 100 ml groundwater sample spiked at 1 p.g 1 1 through a a CP-cartridge b a cartridge filled with a polymer imprinted with terbuthylazine. Peaks 1 = deisopropylatrazine, 2 = deethylatrazine, 3 = simazine, 4 = atrazine, 5 = propazine, 6 = terbuthylazine, I.S. = internal standard (diuron). Reprinted with permission from Ferrer I, Lanza F, Tolokan A, Horvath V, Sellergren B, Horvai G, Barcelo D (2000) Anal Chem 72 3934. Copyright 2000 American Chemical Society... [Pg.143]

Groundwater. According to the U.S. EPA (1986) simazine has a high potential to leach to groundwater. [Pg.1612]

In spite of the legislative measures that have progressively been adopted, many different pesticide substances are detected in Europe s groundwater at levels sometimes greater than the Directive 2006/118/EC maximum allowable concentration, and the pesticides most commonly found in groundwater appear to be atrazine, simazine and lindane [3, 13]. [Pg.379]

In the Ebro river zone (NE Spain), pesticide concentrations in groundwater were much higher than in the Llobregar river area. Hildebrandt et al. [18, 19] found in groundwater samples collected in 2000-2001 very high levels of metolachlor (10-2000 ng/L) and triazines (2460, 1980, 1270, 790 and 540 ng/L for atrazine, DEA, terbuthylazine, DIA and simazine, respectively). However, 3 years later (2004), triazines concentrations decreased dramatically, whereas metolachlor presented levels even higher (from 2,000 to 5,370 ng/L). [Pg.388]

Another example of the potential pernicious effects of pesticides upon human health is the study conducted at the University of Colorado where researchers have found that higher concentrations of four pesticides - atrazine, simazine, alachlor and metolachlor - in groundwater are significantly associated with higher levels of Parkinson disease. For every 10 pg/L increase of pesticide levels in the drinking water, they found that the risk for Parkinson disease increased by 3% and their water samples had pesticide concentrations ranging from 0.0005 to 20 pg/L [38]. [Pg.391]

Pesticide levels often exceed the requirements posed by the Ground Water Directive (2006/118/EC), thus constituting a serious threat to ground water quality. This becomes especially relevant in those cases in which groundwater are used as human supply source. Of particular concern is the fact that the commercialisation of formulations containing some of the most commonly found pesticides, such as triazines (atrazine, simazine, etc.), lindane have been aheady banned in Europe. [Pg.391]

A population-linked database was developed to assess exposure to the herbicides atrazine and simazine in the drinking water of community water systems (CWS) fed by groundwater and surface water sources in 32 major-use states. These states represent about 99% of the annual atrazine and simazine use in the United States. Herbicide concentration and population data from 1993 through 2000 were paired for each water system and then aggregated to construct state and multistate exposure profiles. [Pg.439]

Beginning in 1993, the USEPA initiated compliance monitoring of finished water for atrazine, simazine, and several other chemicals. Surface water supplies were monitored quarterly, and groundwater supplies were monitored once or twice annually. The purpose was to assess annual running mean concentrations of atrazine and simazine for each CWS for compliance with their respective MCLs (Table 29.1). [Pg.441]

The majority (78%) of the CWS in the 32 states use groundwater as the raw water source (Table 29.2). Thus, the two herbicides databases contain more groundwater (four to five times) than surface water samples (Tables 29.3 and 29.4). The most frequently used limits of quantification (LOQ) for the analysis of atrazine were equal to or less than 0.5ppb (1/6 of MCL) in 28 states, 0.6ppb in one state, and l.Oppb and 2.5ppb in the other two states, respectively. Prior to 1997, two states had an LOQ at the MCL of 3 ppb. The LOQs were lowered in 1997 and subsequent years to less than 1 ppb. The LOQs for simazine were equal to or less than 0.8ppb (—1/5 of MCL) in 27 of the 31 states. LOQs of l.Oppb (1/4 of MCL) and 2.0ppb (1/2 of MCL) were used in the other four states. By 2005, almost all CWS in the United States used LOQs of 0.1 ppb or lower. [Pg.442]

Simazine was detected less frequently than atrazine in the quarterly samples from CWS. It was not detected in 98.8% of the samples (Table 29.6). Again, groundwater samples had more nondetections than surface water. [Pg.444]

Private wells were not included in the PLEX database. Persons receiving potable water from private wells were not quantitatively assessed, but represent approximately 6% of the US population (USEPA, 1993). National groundwater studies of private wells have shown that more than 98% have nondetectable atrazine concentrations or concentrations <0.02ppb (Holden et al., 1992 USEPA, 1992b), and more than 99.8% have simazine concentrations that are either... [Pg.447]

Fig. 15.6. LC/DAD chromatogram at 220 nm obtained after preconcentration of 100 mL of groundwater sample spiked at 1 /rg/L through (a) a blank cartridge prepared using a non-imprinted control polymer and (b) a cartridge prepared using a polymer imprinted with ter-butylazine. Peaks 1 = /eisopropylatrazine, 2 = feethylatrazine, 3 = simazine, 4 = atra-zine, 5 = propazine, 6 = terbutylazine and I.S. = diuron (internal standard). Fig. 15.6. LC/DAD chromatogram at 220 nm obtained after preconcentration of 100 mL of groundwater sample spiked at 1 /rg/L through (a) a blank cartridge prepared using a non-imprinted control polymer and (b) a cartridge prepared using a polymer imprinted with ter-butylazine. Peaks 1 = /eisopropylatrazine, 2 = feethylatrazine, 3 = simazine, 4 = atra-zine, 5 = propazine, 6 = terbutylazine and I.S. = diuron (internal standard).
A California groundwater survey in 1982 showed no pesticides (i.e., DBCP, EDB, carbofuran, or simazine) in the Santa Maria or Salinas Valley groundwater basins (76). DBCP was present in 6 of 23 wells in the Upper Santa Ana basin (0.1-8 ppb), and in 21 of 166 wells in the San Joaquin basin (0.1-10 ppb). The authors were unable to correlate well characteristics with DBCP concentration in water. Simazine was also found in 5 wells, carbofuran in 1 well, and EDB in 2 wells. [Pg.37]

Zalkin, F. Wilkerson, M. Oshima, R. J. Pesticide Movement to Groundwater. Vol. II. Pesticide Contamination in the Soil Profile at DBCP, EDB, Simazine and Carbofuran Application Sites" Calif. Dept. Food and Agric. Sacramento, Calif. Final Rep., EPA Grant E009155-79 1984. [Pg.42]

The triazine herbicides, atrazine and simazine have recently been encountered in groundwater in Northern California and in the Los Angeles Basin at levels ranging from 0.4 to 2.0 ppb (2J5). The chemical structures of these two compounds are shown below ... [Pg.430]

For example, simazine is involved in a groundwater issue. Simazine has an LDbU of approximately 5,000 mg/kg [13]. This is less acutely toxic than table salt, which has an LD q of approximately 4,000 mg/kg [14]. Simazine can be fed in the diets of rodents for their lifetime at 3,000 ppm without any remarkable effect [15] or administered daily at 215 mg/kg/day in an National Cancer Institute (NCI) bioassay without oncogenic effect [16]. [Pg.436]


See other pages where Simazine groundwater is mentioned: [Pg.415]    [Pg.425]    [Pg.428]    [Pg.441]    [Pg.477]    [Pg.142]    [Pg.375]    [Pg.380]    [Pg.387]    [Pg.154]    [Pg.62]    [Pg.57]    [Pg.57]    [Pg.61]    [Pg.245]    [Pg.359]    [Pg.439]    [Pg.440]    [Pg.440]    [Pg.440]    [Pg.441]    [Pg.442]    [Pg.446]    [Pg.453]    [Pg.456]    [Pg.467]    [Pg.236]    [Pg.2082]    [Pg.382]    [Pg.174]   
See also in sourсe #XX -- [ Pg.6 , Pg.454 ]




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