Persistence in Soil and Water

Mobility and leachability of diflubenzuron in soils is low, and residues are usually not detectable after 7 days in water half-time persistence (Tbl/2) is usually less than 8 days and 

The presence of sediments in diflubenzuron marine microcosms results in rapid removal from seawater and ultimately a reduction in mortality of larval crustaceans. But marine sediments that exceed 200.0 xg difluben-zuron/kg - levels normally encountered at application rates for control of salt marsh mosquitos - could be detrimental to juvenile and adult crustaceans that consume detritus and organic matter on the surface of the marsh or at the water-sediment interface. 

In Europe and elsewhere, diflubenzuron is used in a variety of ways not permitted in the United States. Eor example, diflubenzuron and other insect growth regulators are fed as admixtures to rations of chickens, cattle, and swine in order to control fly 

Diflubenzuron applied aerially to forest leaves in the spring growing season did not persist when the leaves were placed in sAeam water. Residues on oak leaves decreased 36% in July, and 23% in August within the flrst 

48 h of stream incubation, reaching 90% loss within 3 weeks. However, in December, after 54 days in the stream, there was no significant loss from leaves of red maple, oak, or poplar. The persistence of diflubenzuron to forest leaves under winter conditions is attributed to the increased stability of diflubenzuron at cold temperatures, the greater retention to leaves at low temperatures, and the reduction in microbial degradation. In view of the persistence of diflubenzuron on hardwood leaves at low stream temperatures, nontarget aquatic organisms that consume these leaves may be exposed for extended periods with possible adverse effects. 

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Persistency Very persistent in soil and water and on surfaces. 

Table 17.2 (continued) Diflubenzuron Persistence in Soil and Water... 

Another problem or consideration that may interfere with some aspects of allelopathy (especially in field experiments) has arisen over the past fifty years with the introduction and use of a multitude of xenobiotic compounds as insecticides, fungicides, plant growth regulators, harvest aids, and herbicides. A variety of such compounds have been and continue to be used on a world-wide scale. Some of these chemicals and/or their transformation products are persistent in soils and water. Other such chemicals are routinely applied at various times during a year. These xenobiotics may interfere or interact with naturally occurring allelochemics and thus alter or even mask certain natural allelochemical effects. Researchers will have a more difficult time to find natural areas that do not contain xenobiotic... 

Synonyms TNB a-Hydroxy-a-phenylbenzeneace-tic acid l-Azabicyclo[2,2,2]octan-3-yl ester Agent 15 3-QNB QNB Agent buzz Description BZ is a glycolate anticholinergic chemical related to atropine, scopolamine, and hyoscyamine. It is odorless, nonirritating, and is stable in most solvents. It has a half-life of 3 weeks in moist air and is extremely persistent in soil and water as well as on most surfaces. Agent 15, believed to have been stockpiled in Iraq, is speculated either to be identical to BZ or a closely... 

Triazine herbicides are moderately persistent in soils and water (10-18 months) with atrazine being one of the more persistent of the group. Laboratory and field data have shown that the disappearance of atrazine from soil is influenced by temperature, pH, moisture content, and organic matter content the effect of temperature and pH on the half-life of atrazine in... 

BIOLOGICAL PROPERTIES long term persistence in soil and water sticks strongly to soil particles and does not leach rapidly into underground water soil half-life 2-15 yrs aerobic half-life 2-15.6 yrs anaerobic half-life 16-100 days surface water half-life 7-350 days ground water half-life 16-31.3 days can be detected in water by EPA Method 608 gas chromatography, or EPA Method 625 gas chromatography plus mass spectrometry... 

QNB is extremely persistent in soil and water and on most surfaces with a half-life of 3-i weeks in moist air. 

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