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Chemical Fact Sheet

Chemical Abstract Number (CAS #) 72559
CASRN 72-55-9
Synonyms4,4'-DDE
Benzene, 1,1'-(dichloroethenylidene)bis[4-chloro-
p,p'-DDE
Analytical Methods EPA Method 508
EPA Method 608
EPA Method 617
EPA Method 625
EPA Method 8081
Molecular FormulaC14H8Cl4

Link to the National Library of Medicine's Hazardous Substances
Database for more details on this compound.

Consumption Patterns NOT USED COMMERCIALLY IN USA
Apparent Color WHITE, CRYSTALLINE SOLID
Melting Point 88.4 DEG C
Molecular Weight 318.0
Environmental Impact DDE is an impurity in DDT as well as a biodegradation product of DDT and therefore occurs in the environment as a result of the use of DDT as an insecticide. If released to soil it will adsorb very strongly to the soil and will not be expected to leach through soil to groundwater. It will not hydrolyze under normal environmental conditions and will probably not significantly biodegrade. Evaporation from the surface of soils with low organic content (such as sandy soils) may be significant, but adsorption of DDE to soils may reduce the rate of evaporation. If released to water it will adsorb very strongly to sediment, bioconcentrate in aquatic organisms, and be subject to photolysis with half-lives of 15-26 hrs for photodegradation by environmentally significant wavelengths of light. It will not appreciably hydrolyze or biodegrade in water. Evaporation from water may be important with half-lives of 5.6-6.4 hrs predicted for evaporation from a river 1 m deep, flowing at 1 m/sec with a wind velocity of 3 m/sec; however, the expected adsorption of DDE to sediments may retard the evaporation process. If DDE is released to the atmosphere it may be subject to direct photolysis. The estimated vapor phase half-life in the atmosphere is 4.63 hrs as a result of reaction with photochemically produced hydroxyl radicals. The major translocation mechanisms for DDE in air is fallout and washout since DDE should adsorb to particulate matter. General human exposure will mainly be from consumption of contaminated food. Minor exposure may also occur through the manufacture and use of DDD as an insecticide.
Environmental Fate AQUATIC FATE: The observed persistence of DDE in the environment is partially due to its being sorbed to sediments or biota where no light for photolysis is available, but photolysis of DDE is likely to be an important fate in the ultimate transformation of DDE in aquatic systems. AQUATIC FATE: Pesticides can be spread by major rivers & by ocean currents. A study of the distribution of DDT residues along coastal California was made by using an indicator organism, the common surf-zone sand crab, Emerita analoga, which is a nonmigrating common particulate filter-feeder species in that area. It was found that the animals near the Los Angeles County sewer outfall contained over 45 times more DDT (mostly in the form of DDE) derivatives than animals near major agricultural drainage areas. This was attributed to the nearby Montrose Chemical plant, which was the sole DDT manufacturer in the US at that time. The farthest transport of DDT along the shore was 3573 km. It is likely that the higher residues toward the north represented the work of ocean currents. This finding is supported by evidence that DDE/DDT ratios were lower on the northern side of the peak contamination area; that is, "fresh" contaminants are expected to have a lower DDE/DDT ratio than older sewage samples. While biological transport cannot be neglected from biological & health standpoints, its relative contribution to the globial movement of pesticides (in terms of quantity) is small. ATMOSPHERIC FATE: That the residues of pesticides & industrial organic chemicals are transported in the atmosphere over long distances is now well established. Dieldrin, p,p'-DDT, & p,p'-DDE were detected in air samples collected over Bantry Bay in Southwest Ireland, a place remote from areas of use of organochlorine compounds. ATMOSPHERIC FATE: Under simulated atmospheric conditions, both DDT and DDE decompose to form carbon dioxide and hydrochloric acid. TERRESTRIAL FATE: If DDE is released to soil, it will adsorb very strongly to the soil and should not leach to the groundwater. It will not appreciably hydrolyze under normal environmental conditions and will not significantly biodegrade. Evaporation from the surface of soils with low organic content may be significant. AQUATIC FATE: If DDE is released to water, it will adsorb very strongly to sediment and will bioconcentrate in aquatic organisms. It will not appreciably hydrolyze or biodegrade. It will be subject to direct photolysis with a half-life of 1.1 days and 15-26 hrs reported for photolysis of DDE by sunlight in San Francisco Bay water and wavelengths >310 nm in water, respectively . Evaporation may be important with a half-life of 5.6-6.4 hrs predicted for evaporation from a model river 1 m deep, flowing at 1 m/sec with a wind velocity of 3 m/sec; however, the expected adsorption of DDE to sediments may retard the evaporation process. ATMOSPHERIC FATE: If DDE is released to the atmosphere, it may be subject to direct photolysis. The estimated vapor phase half-life in the atmosphere is 4.63 hrs as a result of reaction with photochemically produced hydroxyl radicals . The major translocation mechanisms for DDE in air is fallout and washout since DDE should adsorb to particulate matter.
Drinking Water Impact DRINKING WATER: p,p'-DDE: New Orleans, LA, 3 drinking water plants, 67% pos, identified, not quantified (nq) . US, identified, nq . Ottawa, Canada tap water, < 0.016 ppb . DDE: Potable water, rural South Carolina: Chesterfield County, 29.2% pos, not detected (nd)-200 ppt, avg, 17 ppt, median, nd; Hampton Country, 54.4% pos, nd-30 ppt, avg, 8 ppt, median, nd . California, well water, 54 wells, identified, nq . USA drinking water, 0.05 ppb . SURFACE WATER: p,p'-DDE: Hawaii, 1970-71, 46 samples, not detected (nd)-1.0 ppt, 13 rural areas, 0.1-0.5 ppt, avg 0.3 ppt, 24 urban areas, 0.2-0.8 ppt, avg 0.5 ppt . Illinois waters of Lake Michigan, range (avg) in ppt, 1970, 71, 72: 0.6-1.6 (1.1), 1.7-2.9(2.5), 3.9-20.3(9.2), respectively(8). o,p'-DDE: Illinois waters of Lake Michigan, 1971-72, nd(8). DDE: US, STORET database, 5,333 samples, 48.0% pos, median 0.001 ppb(10). Selected western USA streams, 1965-66, 11 streams, 64% pos, 114 samples, 16% pos, 5-20 ppt (rounded to nearest 5 ppt), avg 9.2 ppt . North Atlantic, 10 sites, 100% pos, 0 m depth (100% pos), < 0.35-18.1 ppt, 50 m depth (70% pos), < 0.35-10.3 ppt, 500 m depth (70% pos), 0.1-15.4 ppt, 1000 m depth (60% pos), 0.8-4.9 ppt . Niagara River, 1979, 6% pos samples, avg < 1 ppt, 1981, total water samples, 60% pos, detected-0.5 ppt, avg 0.2 ppt . USA, 1964-68, 5-year summary, 84 stations, 3.6% pos, 529 damples, max concn 50 ppt . USA, selected western streams: 1966-68, 20 stations, 45% pos, 0.01-0.06 ppb(6); 1968-71, 20 stations, 40% pos, 0.01-0.08 ppb(7). Southern Florida, 1968-72, 362 samples, 4% pos(9). Surface water: In a survey of 11 watersheds in southwestern Ontario, DDT group compounds were present in 93% of the 949 stream water samples analyzed. DDE was the predominant component of DDT. The parent cmpd was frequently found in high concn during high flow conditions & was almost absent in months of low stream flow. High flow rates, higher loads of suspended solids, & higher delivery of DDT to the stream were well correlated. Thus, with a 57 to 66% of the total annual water flow & 66 to 73% of the total suspended particle load from January to April, 58 to 84% of the annually transported DDT was carried in this period. No decline in the quantity of the sum DDT transported from 1975 to 1977 was observed, in comparison with 1971, the year when DDT was deregistered in Canada. Soils were the main source of DDT to these streams. RAINWATER/SNOW: Canadian Network, precipitation, 1977-80, 12 sites, 83% pos, 210 samples, range of pos samples 0-28%, 0.1-5 ppt . Ohio, 3 cities, 21 samples, 0.005-0.05 ppb, avg 0.025 ppb . Rainwater: the presence of DDE in rainwater collected at Cincinnati, Ohio in 1965 has been reported/. Lake water: The top few micrometers layer of the water column in any natural body of water constitutes a separate enity by itself, being characterized by its richness in hydrophobic organic substances. It has been shown that surface slicks act as concentrators of pesticides in the marine environment, several studies have reported the occurrence of high concn of pesticide residues in the surface microlayers that act as a repository & a sink for anthropogenic chemicals. In the surface slicks collected off the Florida coast (all values in ug/l): 0.061 to 9250, p,p'-DDE /has been reported/. If the surface film is est as 5 molecular layers thick (1X10-2 um) & all the chemical constituents were in this layer, the actual concn in this film, relative to the subsurface water, would be 1.5X10 4 times. Wind-generated lake foam & surface layers have been reported to be rich in fatty acids, esters, & alcohols, which are excellent concentrators of PCBs & other chlorinated hydrocarbons. In Lake Mendota, Wisconsin, the concn of the various pollutants observed in the foam were (all values in ng/l): p,p'-DDE, 175 whereas in the lake water, the concn was less than 1 ng/l. The foam acts as a scavenger & a trap for the organic pollutants. EFFL: DDE: US, STORET database, 45 samples, 31.1% pos, median, 0.010 ppb . US, industrial wastewaters, raw (treated): foundries, 14(9) samples, 100%(100) pos, 5-20(5-10) ppb, avg 7.1(5.5) ppb, metal finishing, 37 samples, 11% pos, 10-53 ppb, avg 14 ppb, aluminum forming, (16 samples, 88% pos, <0.01-7 ppb avg <0.76 ppb) .

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