United States
                             Environmental Protection
                             Agency
                     Office of Water
                     4601
            EPA811-F-95-003k-T
                   October 1995
                              National  Primary Drinking
                             Water Regulations
                              Dinoseb
  CHEMICAL/ PHYSICAL PROPERTIES

  CAS NUMBER: 88-85-7

  COLOR/ FORM/ODOR:
    Yellow/orange crystals; pungent odor

  M.P.:  38-42° C B.P.: N/A

  VAPOR PRESSURE: 1 mm Hg at 151.1° C

  OCTANOL/WATER PARTITION (Kow):    N/A

  DENSITY/SPEC. GRAV.: 1.26 at 45° C
SOLUBILITY: 0.052 g/L of water at 25° C;
  tends to form salts which are highly
  soluble in water

SOIL SORPTION COEFFICIENT:
  Koc =124 (measured); high mobility in
  soil

ODOR/TASTE THRESHOLDS:  N/A

BlOCONCENTRATION FACTOR:
  BCF = 68 (est.); not expected to
  bioconcentrate in aquatic organisms.
HENRY'S LAW COEFFICIENT:
  5.04x10-* atm-cu m/mole (est.)

TRADE NAMES/SYNONYMS:
  2,4-dinitro-6-(1 -methyl-propyl) phenol;
  Dinitrobutylphenol; Aatox; Chemox;
  Gebutox; Knox-weed; Basantte; BNP
  20; Butaphene; Dibutox; Dinitrall;
  Dinitro; Desicoil; Dow Selective Weed
  Killer; Hivertox; Ladob; Laseb;
  Nitropone C; Dytop; Premerge; Hel-fife;
  Caldon; Kiloseb; Sinox General;
  Subitex.
DRINKING WATER STANDARDS
  MCLG:      0.007 mg/L
  MCL:       0.007 mg/L
  HAL(child):  1 to 10 day: 0.3 mg/L
             Longer-term: 0.01 mg/L

HEALTH EFFECTS SUMMARY
  Acute: EPA has found dinoseb to potentially cause the
following health effects from acute exposures at levels
above the MCL: sweating, headache, mood changes.
  Drinking water levels which are considered "safe" for
short-term exposures: For a 10-kg (22 Ib.) child consum-
ing 1 liter of water per day, a one- to ten- day exposure to
0.3 mg/L or tip to a 7-year exposure to 0.01  mg/L.
  Chronic:   Dinoseb has the potential to cause the
following health effects from long-term exposures at
levels above the MCL: decreased body and thyroid
weight, degeneration of testes; thickening of intestinal
lining.
  Cancer: There is inadequate evidence to state whether
or not dinoseb has the potential to cause cancer from
lifetime exposure in drinking water.

\JSAGE PATTERNS
  Dinoseb is a contact herbicide used as the ammonium
oramine salt for post-emergence weed control in cereals,
undersown cereals, seedling lucerne and peas.
                 Oil solutions of dinoseb are used for pre-emergence
               control of annual weeds in beans, peas and potatoes, for
               pre-harvest dessication of hops, leguminous seed crops,
               potatoes and for control of runners and suckers in straw-
               berries and raspberries.
                 Dinoseb is also used as a com yield enhancer and an
               insecticide and miticide.
                 1982 production of dinoseb was reported as 6.2 million
               Ibs., with consumption estimates as follows: as an herbi-
               cide for soybeans, 32%;  vegetable, 23%; deciduous
               fruits and  nuts, 11%; peanuts, 8%; citrus, 3%; grain
               crops, 2%; other field crops, 6%; industrial/commercial
               uses, 15%.

               RELEASE PATTERNS
                 Release of dinoseb has resulted primarily from its use
               as an herbicide on a variety of weeds.
                 Since dinoseb is not a listed chemical in the Toxics
               Release Inventory, data on releases during its manufac-
               ture and handling are not available.

               ENVIRONMENTAL FATE
                 Dinoseb is expected to biodegrade in slowly and bind
               weakly to soil. Therefore, leaching in soil is possible and
               dinoseb has been detected in groundwater. However, it
               may bind more strongly to clay soils, especially at acidic
               pH. Photolytic degrdration of dinoseb from soil surface
               may be important. Volatilization is not expected to be
               significant. The laboratory-measured evaporation half-
October 7995
         Technical Version
             Printed on Recycled Paper

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life for dinoseb from a soil surface was 26 days. In the
absence of volatilization, the half-life of dinoseb in the
vadose zone sandy loam soil was estimated to be about
100 days.
   Dinoseb may photodegrade in surface  water with a
half-life of 14-18 days. The estimated Henry's Law con-
stant of 5.04X10-4 atm cu m/mol suggests that volatiliza-
tion of dinoseb from water will be slow.  It  is unlikely to
undergo significant biodegradation in most natural wa-
ters. Volatilization from water is expected to be slow.   .
   The half-life for the reaction  of vapor phase dinoseb
with photochemically generated hydroxyl radicals in the
atmosphere was estimated to be 14.1 days. Wet deposi-
tion may remove some of the compound from air.
   Bioconcentration is expected to be insignificant. A
bioconcentration  factor  (BCF)  of 68 for dinoseb  was
estimated from its water solubility (50 mg/L).
   Exposure to dinoseb in humans is expected to occur
primarily in workers using the herbicide.
                                                          OTHER REGULATORY INFORMATION
                                                         MONITORING:
                                                         FOR GROUND/SURFACE WATER SOURCES:
                                                           INITIAL FREQUENCY-  4 quarterly samples every 3 years
                                                           REPEAT FREQUENCY- If no detections during initial round:
                                                                          2 quarterly per year if serving >3300 persons;
                                                                          1 sample per 3 years for smaller systems
                                                         TRIGGERS - Return to Initial Freq. if detect at > 0.0002 mg/L


                                                         ANALYSIS:
                                                         REFERENCE SOURCE             METHOD NUMBERS
                                                         EPA 600/4-88-039             515.1; 515.2; 555


                                                         TREATMENT:
                                                         BEST AVAILABLE TECHNOLOGIES
                                                         Granular Activated Charcoal


                                                         FOR ADDITIONAL INFORMATION:
                                                         * EPA can provide further regulatory and other general information:
                                                         • EPA Safe Drinking Water Hotline - 800/426-4791

                                                         4 Other sources of lexicological and environmental fate data include:
                                                         • Toxic Substance Control Act Information Line - 202/554-1404
                                                         • Toxics Release Inventory, National Library of Medicine - 301/496-6531
                                                         • Agency for Toxic Substances and Disease Registry - 404/639-6000
                                                         • National Pesticide Hotline - 800/858-7378
October 1995
Technical Version
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