Atrazine Europe

Several hundred-pesticide compounds of diverse chemical structures are widely used in the United States and Europe for agricultural and non-agricultural purposes (Fig. 10). Some are substitutes for organochlorines, which were banned due to their toxicity, persistence, and bioaccumulation in environmental matrices. According to a report published by the US-EPA, a total of 500,000 tons of pesticides was used in 1985 [144, 145, 148]. As far as specific pesticides are concerned, worldwide consumption of Malathion and Atrazine in 1980 amounted to 24,000 and 90,000 tons, respectively [149,150]. In the Mediterranean countries, 2100 tons of Malathion (active ingredient) were sprayed during the same period compared to 9700 tons in Asia [150]. 

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]. 

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. 

Groundwater. Atrazine dominated the world herbicide market in the 1980s, and contamination of groundwater has been reported in several locations in the U.S., Europe, and South Africa. Successful biodegradation has been achieved with indigenous organisms in laboratory mesocosms after a lag phase, and once activity was found, it remained, It is clear that intrinsic remediation is likely to lead to the disappearance of atrazine from groundwaters. 

GS-13529, terbuthylazine A chlorotriazine similar to atrazine and simazine, terbuthylazine was first introduced to the scientific community in 1966. Terbuthylazine also provided broad-spectrum weed control in com. Studies comparing efficacy showed that generally atrazine was more effective than terbuthylazine on both broadleaf and grassy weeds. Since terbuthylazine was less efficacious than atrazine in weed control trials conducted in the United States in the late 1960s, it was not commercially developed for com in the United States. However, development for use in corn and vines continued for Europe and other countries where the weed control needs differed and the weed control differences between atrazine and terbuthylazine were not limiting. 

By the end of the 1950s, atrazine was introduced for weed control on railroad tracks and rights-of-way and in com production in Europe. The initial federal approval in the United States occurred in December 1958 when the US Department of Agriculture (USDA) registered Geigy Atrazine 50W for use in com and for nonselective weed control in noncrop areas. In 1959 Atrazine 80 W was registered, which in 1970 was trademarked as AAtrex and quickly became a leading herbicide in the United States. 

While it is difficult to determine an accurate total for the amount of atrazine previously used in com in Europe, Table 5.3 describes atrazine use in forage com in the United Kingdom. The crop expanded rapidly there during the late 1990s due to changes in the method of price support. 

Terbuthylazine is another novel chloro-.v-triazinc that has found very important uses in Europe for control of weeds in corn, as well as vineyards and orchards. It was introduced at lower application rates than the early atrazine rates and was not registered for use in roads, railways, and noncropland. Terbuthylazine is used in combination with other herbicides and has continued to help replace some uses of atrazine and simazine in many countries of Europe. 

Weed resistance to the triazine herbicides was first identified in the late 1960s, with a biotype of common groundsel that was resistant to simazine (Ryan, 1970). Since then, resistance to triazine herbicides has been reported in many weed species (Holt and LeBaron, 1990 LeBaron and McFarland, 1990 Gronwald, 1994). Most cases of triazine resistance have been reported in the US, Canada, and Europe, where triazine herbicides have been used extensively in corn monocultures (LeBaron and McFarland, 1990 Stephenson et al., 1990 LeBaron, 1991). Most of the. v-triazinc-resistant weed species have been selected against atrazine and usually show a high level of cross-resistance to other. v-triazine herbicides. In most cases, these weeds also show a low level of resistance to as-triazinones (e.g., metribuzin). Triazine-resistant weeds are often less vigorous than nonresistant weeds, which facilitates their management. 

Within North America and a few other countries, most triazine-resistant weed biotypes have been reported after repeated use of atrazine in com and sorghum. In some areas of Western Europe and other countries, triazine-resistant weeds have been reported after repeated use of simazine in orchards and along roadsides. A few triazine-resistant weeds (e.g., kochia, cheatgrass, and common groundsel) have biotypes with triazine resistance in nurseries and perennial tree crops, as well as along railways and roadsides. 

The Lyonnaise des Eaux in France [4.116] has developed a process for the denitrification of underground waters in order to produce drinking water. This process combines a bioreactor with adsorption by powdered activated carbon, together with a hollow-fiber UF unit. This process allows the elimination of nitrates, nitrites, pesticides, and herbicides (atrazine, diethylatrazine, simazine, metabenzthiazuron, and urea derivatives, etc.) as well as taste and odor compounds. These molecules are frequently present in underground waters in Europe, as a result of past intensive agricultural practices. The UF membrane unit also disinfects the water by removing protozoa, bacteria, and viruses. 

Herbicides are the most used pesticides in the world for more than 40 years, with 45% of the total market value in 1993. Among the top ten herbicides used in the world, atrazine and glyphosate are used worldwide, and interesting differences appear between the U.S.A and Europe regarding this top ten list. Urea herbicides belong to this list in Europe and contaminate many water sources whereas in the U.S.A these are not used at all. More than 80% of the herbicide use is concentrated in three agriculture areas North America, western Europe, and east Asia. 22% of the total herbicides are also found for nonagricultural uses with a lot of triazines and ureas in Europe. ... 

Chloroacetanilide herbicides (e.g., alachlor, metolachlor, and acetochlor) are of an important class of herbicides used to control grass weeds in various crops. Alachlor and metolachlor have been widely used (both in the U.S.A and in Europe) for more than 20 years. Acetochlor, a herbicide used for maize, has been on the United States market since 1994, following approval by the U.S. Environmental Protection Agency. This approval will be renewed, however, only if the total quantity of other herbicides used on this crop, including atrazine, decreases. Acetochlor was approved in France in 2000 and is now used in substitution programs. 

Despite the use of this policy over a period of almost 30 years, there is none the less a problem of pesticide contamination in groundwater across Europe. In many European countries the concentration levels of specific pesticides (e.g. atrazine) have breached the EU set standard. 

BW daily for a 60-kg person. Both TRMC estimates are substantially below the proposed limit of 0.0375 mg/kg BW daily. Lifetime exposure to drinking water concentrations of 2.3 (xg atrazine/L poses negligible risk to human health, as judged by the no adverse effect level of 7.5 xg/L when 1% of the allowable daily intake is obtained from this source. Higher allowable concentrations are proposed over short periods 123.0 xg/L for adults and 35.0 jig/L for children, over a 10-day period. The proposed drinking water criterion to protect human health in Western Europe is <0.1 Jig/L. In the United States, it should not exceed 3.0 jig atrazine/L drinking water, although some authorities recommend less than 3.6 jig atrazine/L. 

Atrazine failed to get reregistration in Europe in October 2002 because of suggestions that it could be linked to increased cancer risks. The US-EPA concluded that there have been no studies confirming increased risk... 

The class of urea herbicides is widely being eliminated in Europe, but, more distinctively, the important class of triazine herbicides is disappearing from the EU herbicide market. None of their some ten representatives in Europe where sales can be recorded have made it into Annex 1, except terbutylazine, which is still pending for the time being. The traditionally most important triazine representatives, atrazine and simazine, have not passed the EU Review Program and will have to be replaced by new chemistry in the EU, while both substances, particularly atrazine, still represent a significant importance in the US market, e.g., atrazine sales in the US accounted for some 165 Mio Euro in 2004, since this compound is widely and efficiently used in the US corn market, also in combination with Roundup-Ready. 

This is photostable and complete mineralisation was not observed. In some countries restrictions on the use of s-triazines, such as atrazine, have been implemented, while in others, these have even been banned. Atrazine has, however, been detected above the recommended levels (0.1 ppb or pg dm ) throughout Europe and the United States and is considered as a priority toxic substance by the EC. Considerable efforts are being made to eliminate it from water. 

So, should we still use atrazine All decisions involve tradeoffs, and the answer is rarely obvious. Does the benefit of increased food production outweigh possible health risks of a pesticide Do the beneficial effects of a new drug outweigh a potentially dangerous side effect in a small number of users Different people will have different opinions, but an honest evaluation of facts is surely the best way to start. At present, atrazine is approved for continued use in the United States because the EPA believes that the benefits of increased food production outweigh possible health risks. At the same time, though, the use of atrazine is being phased out in Europe. 

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