Herbicides water pollution from

The first known incidence of pollution from approved herbicides was identified in 1972 in Essex, where tomato plants grown by commercial producers became malformed. The plants had been watered from public water supplies fed from a reservoir. The reservoir in turn abstracted water from a river supplemented by a water transfer scheme, from the River Cam in Cambridgeshire. Pollution from a factory manufacturing 2,3,6-TBA was identified as the cause and the problem was subsequently resolved by treating the effluent. 

Readman JW, Albanis TA, Barcelo D et al (1993) Herbicide contamination of mediterranean estuarine waters - results from a Med Pol pilot survey. Mar Pollut Bull 26 613-619... 

We tried to obtain a herbicide binder from a tetrapeptide library. The herbicides diuron (DCMU) [3-(3,4-dichlorophenyl)-l, 1-dimethylurea] and atrazine (2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine) are widely used for crop protection (Fig. 8.4). However, due to their widespread use, they contribute greatly to water pollution on a worldwide scale.24,25 Many risk characterizations or epidemiological studies on triazine herbicides (i.e., atrazine, simazine, cyanazine) have been reported including the clastogenic potentials of atrazine and simazine to Chinese hamster ovary cells26 or their carcinogenicity.27,28 The standard level of atrazine in... 

Common pollutants include traces of human or animal waste disease organisms radioactive materials toxic metals such as lead or mercury agricultural chemicals such as pesticides, herbicides, or fertifizers and high-temperature water discharged from industrial plants. Polluted water may be dangerous to drink, may harm crops, and may cause eutrophication. 

Markers of water pollution show the presence of pollution sources. These include herbicides indicative of agricultural runoff, fecal coliform bacteria that are characteristic of pollution from sewage, and pharmaceuticals, pharmaceutical metabolites, and even caffeine that show contamination by domestic wastewater. 

Herbicides are applied over millions of acres of farmland worldwide and are widespread water pollutants as a result of this intensive use. A 1994 report by the private Environmental Working Group indicated the presence of herbicides in 121 Midwestern U.S. drinking water supplies. The herbicides named were atrazine, simazine, cyanazine, metolachlor, and alachlor, of which the first three are the most widely used. These substances are applied to control weeds on com and soybeans, and the communities most affected were in the Com Belt states of Kansas, Nebraska, Iowa, Illinois, and Missouri. The group doing the study applied the EPA s strictest standard for pesticides in food to water to come up with an estimate of approximately 3.5 million people at additional risk of cancer from these pesticides in drinking water. 

The preparation of soils for crops, planting, and tilling raises dust as a fugitive emission. Such operations are shll exempt from air pollution regulations in most parts of the world. The application of fertilizers, pesticides, and herbicides is also exempt from air pollution regulations, but other regulations may cover the drift of these materials or runoff into surface waters. This is particularly true of the materials are hazardous or toxic. 

Significant levels of herbicides have also been detected in rivers, although these are usually transitory. Heavy rainfall can move herbicides from agricultural land to nearby ditches and streams due to runoff, and in soils that are high in clay, percolation of water occurs through deep fissures with consequent movement into neighboring water courses. Such events under extreme weather conditions are likely to have contributed to the pulses of herbicide contamination observed in some rivers. Questions have been asked about possible effects of such episodic pollution on populations of aquatic plants. 

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