Herbicides, detection

Sergeyeva TA, Piletsky SA, Brovko AA, Slinchenko EA, Sergeeva LM, El skaya AV. Selective recognition of atrazine by molecularly imprinted polymer membranes. Development of conductometric sensor for herbicides detection. Anal Chim Acta 1999 392 105-111. 

Table 30.2 shows that atrazine was detected most frequently with a maximum concentration of 2.1 pg/L, which is less than the health standard of 3ppb set by USEPA. In fact, the majority of the detections for atrazine had a concentration range of 0.05-0.2 pg/L. DEA was detected in 32.1% of the samples and the highest concentration of DEA was 0.59 pg/L. Table 30.2 shows the maximum concentration of triazine herbicides detected. 

During the summer of 1997, water samples were collected and analyzed for herbicides from 32 Playa Lakes of the High Plains that receive drainage from both cotton and corn agriculture in West Texas (Figure 30.1). The major cotton herbicides detected in the water samples were diuron, fluometuron, metolachlor, norflurazon, and prometryn. Atrazine and propazine also were routinely detected in samples from the Playa Lakes. 

Herbicide concentrations exhibited distinct geographic and seasonal patterns. The highest concentrations occurred in midwestem Com Belt states following herbicide application to cropland. Table 30.4 presents a summary of the occurrence and concentrations of triazine herbicides detected in 5 297 samples collected during the study period by immunoassay (ELISA). A confirmation by GC/MS was made of 2085 of the precipitation samples (Pomes et al., 1998). 

The lowest concentration of herbicide detectable in the atmosphere depends on the sample volume and the collection time. For an absorption sample volume of 5.0 ml. n-decane and a collection time of 24 hours, the lowest detectable atmospheric concentration is 1.0 /xgram/cu. meter for methyl MCP, 0.14 /xgram/cu. meter for the 2,4-D esters, and 0.03 /xgram/cu. meter for methyl 2,4,5-T. 

Pandard P, Rawson DM. An amperometric a al biosensor for herbicide detection employing a carbon cathode oxygen electrode. Environ Toxicol and Water Quality 1993 8 323-333. 

Laberge D, Rouillon R, Carpentier R. Comparative study of thylakoid membranes sensitivity for herbicide detection after physical or chemical immobilization. Enzyme Microb Tech 2000 26 332-336. 

Environmental pollution by toxic chemicals has become one of the worlds most serious problems. Among the most widespread pesticides is photosynthesis inhibiting herbicides, such as atrazine, metribuzin, diuron, bromacil, ioxynil and dinoseb. They all beloi to different families but have a common mode of action binding specifically to the chloroplast D1 protein with subsequent intetmption of the electron and proton flow through Photosystem II. The goal of this chapter is to evaluate the possibility of application of the natural receptor properties of D1 protein in various biosensor systems for herbicide detection. 

Great attention has been paid to the application of thylakoid membranes and photosynthetic microorganisms in environmental pollution control. The biorecognition system based on the binding of certain herbicides to the photosynthetic reaction center of plants and microorganisms seems to be the most direa and simple method for herbicide detection. These systems used as sensor s recognition elements allow the detection of a broad range of herbicides. Unfortunately, their stability and sensitivity are insufficient in the most cases. From this point of view, the DI protein, which binds specifically... 

The basic idea was to monitor the loss of trans-membrane proton gradient, which happens due to Dl protein-herbicide interaction, and to use it for herbicide detection. 

In order to avoid the steric hydrance, herbicide was immobilized covalently on the gold surface through 17-carbohydrate spacer contained thiol group. In order to accelerate the binding, the plastoquinone was extracted by hexane fiom Dl protein before the experiment. For herbicide detection the solution of D1 protein was incubated with different concentrations of the metribuzin. The SPR... 

The calibration curves of the amperomettic sensor for atrazine, simazine and metribuzin (measured at potential -400 mV) in Figiue 21 demonstrate the possibility of the herbicide detection in the range concentration 10 -10 M (standard deviation is about 5 %). 

Piletska E, Piletsky S, Lavrik M et al. Development optical system for herbicide detection based on D1 protein. Agtoecol Biotechnol 1998 74-79. 

These four herbicides have been detected in aquifers throughout the United States (2). The amount of each herbicide detected in lakes, streams, resevoirs, and aquifers has been estimated to be not more than 1.5% of the total amount applied annually (3,4). The percentage of ground water samples containing these herbicides range from 0.09 for acetochlor to 30% for atrazine (2,5). The maximum concentrations for individual detections range from 0.02 ug/L for acetochlor to 5.4 ug/L for metolachlor (2). 

At the St. 1, any herbicides were not detected through the period. At the St. 2, fourteen kind of herbicides were detected. The herbicides included cafenstrole, dimepiperate, dimethametryn, esprocarb, mefenacet, pentoxazone, pretilachlor, pyributicarb, pyriminobac-methyl, simetryn, bensulfuronmethyl, daimuron, imazosulfiiron and pyrazosulfuronethyl. The herbicides detection period of this... 

For most rice herbicides detected in Sakura R. and L. Kasumigaura, the maximum detected concentration levels were below low ppb lebel. Recently, the concentration level of individual herbicide detected in surface water tend to decrease in Japan, the probable reasons are the reduction of rice cultivation areas and increase in number of active ingredient in the market. 

---