Atrazine groundwater

Deladedova, P., Sesana, G., Bersani, M., Riparbelli, C., Maroni, M., 1996 Atrazine groundwater contamination in an intensive agricultural area west of Milan - Italy., Period 1986-1994. Proceedings of the X Symposium Pesticide chemistry, Piacenza, 669-73. 

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. 

With the acceptable concentrations of herbicides in drinking water being taken to very low levels by some regulatory authorities (e.g., the EC), there has been interest in very low levels of atrazine present in some samples of groundwater and in drinking water. This finding illustrates the point that mobility of pesticides becomes increasingly evident as sensitivity of analysis improves. 

Phytodegradation Soils, groundwater, landfill leachate, land application of wastewater Herbicides (atrazine, alachlor) Aromatics (BTEX) Chlorinated aliphatics (TCE) Nutrients (NO, NH4+, PO3) Ammunition wastes (TNT, RDX) Phreatophyte trees (poplar, willow, cottonwood, aspen) Grasses (rye, Bermuda, sorghum, fescue) Legumes (clover, alfalfa, cowpeas)... 

Porter W P, Jaeger J W and Carlson I H (1999). Endocrine, immune, and behavioral effects of aldicarp (carbamate), atrazine (triazine) and nitrate (fertilizer) mixtures at groundwater concentrations . Toxicology and Industrial Health, 15,133-150. 

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... 

Wilson, M.P, E.P. Savage, D.D. Adrian, M.J. Aaronson, T.J. Keefe, D.H. Hamar, and J.T. Tessari. 1987. Groundwater transport of the herbicide, atrazine, Weld County, Colorado. Bull. Environ. Contam. Toxicol. 39 807-814. 

Carlson, Ian H., James W. Jaeger, and Warren P. Porter, 1999. Endocrine, Immune, and Behavioral Effects of Aldicarb (Carbamate), Atrazine (Triazine) and Nitrate (Fertilizer) Mixtures at Groundwater Concentrations. Toxicology and Industrial Health, Volume 15, No. 1-2, Janu-ary-March 1999, p. 133-50. 

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]. 

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... 

Groundwater. According to the U.S. EPA (1986) atrazine has a high potential to leach to groundwater. 

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]. 

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). 

Outside Spain, the profile of pesticide contamination is fairly similar. For instance, Kolpin et al. [28] analysed pesticides in groundwater samples from the United States and found, in samples taken in 2001, triazine concentrations between 50 and 620 ng/L. In groundwater samples collected in Portugal between 2005 and 2008, atrazine and terbuthylazine were also detected [16]. 

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]. 

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. 

The persistence (half-life) of atrazine in the subsurface is governed by chemically and biologically mediated transformations. Because the solubility of atrazine is relatively high ( 30mg/L) compared to its toxicity level in water (5 Lig/L), atrazine has become a hazard to groundwater quality. Atrazine has been detected in groundwater more than any other crop protection chemical two examples of atrazine persistence-transformation in aquifer environments are discussed next. 

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