Dalapon

Pesticide -> EPA IRIS

Herbicides

Active substance -> EU Pesticides database: Not approved

Pesticides -> Herbicides, Other

Pesticide (Dalapon) -> USDA PDB

log Kow= 0.78

0.76

1.34

1.4 (NIOSH, 2024) - Denser than water; will sink

1.4014 at 20 °C

Relative density (water = 1): 1.40

1.40

1.40

Liquid

Colorless liquid [Note: A white to tan powder below 46 degrees F. The sodium salt, a white powder, is often used].

50 % (NIOSH, 2024)

Very soluble in alcohol. Soluble in ether

Very soluble in alkali solvents.

In water, 502,000 mg/L at 25 °C

Solubility in water, g/100ml at 25 °C: 90

50%

Corrosive to iron

Formulations are ... corrosive to equipment.

374 °F at 760 mmHg (USCG, 1999)

190 °C

190 °C

374 °F

374 °F

When heated to decomposition it emits toxic fumes of /hydrgen chloride/.

Decomposes >191 °C

Danger

H315: Causes skin irritation [Warning Skin corrosion/irritation]

P264, P264+P265, P273, P280, P302+P352, P305+P354+P338, P317, P321, P332+P317, P362+P364, and P501 (click each P-code to see the statement)

Danger

H302 (14%): Harmful if swallowed [Warning Acute toxicity, oral]

P264, P264+P265, P270, P273, P280, P301+P317, P302+P352, P305+P354+P338, P317, P321, P330, P332+P317, P362+P364, and P501 (click each P-code to see the statement)

Hazard Traits - Nephrotoxicity and Other Toxicity to the Urinary System

Dalapon: Does not have an individual approval but may be used under an appropriate group standard

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

Combustible. Irritating fumes of hydrochloric acid may form in fire. Volatilizes with steam. (USCG, 1999)

Gives off irritating or toxic fumes (or gases) in a fire.

California State Dept Food and Agriculture. Pesticide Use Report Annual 1984, pp.31-32.

Shore FL et al; Report Iss EPA/600/4-85/060 PB86-108484/GAR p 136 (1985). Hazardous waste detection of chlorinated herbicides.

Hill EF, Camardese MB; US Fish Wildl Serv Fish Wildl Tech Rep 2: 1-147 (1986). The report provides the most comprehensive data base available for avian subacute dietary toxicity tests and is primarily intended for use in ranking toxicities by a standard method that has a reasonable degree of environmental relevance.

Folmar LC; Tech Pap US Fish Wildl Serv 88: 1-16 (1977). Toxicity of dalapon, dichlobenil and endothall to aquatic organisms is discussed.

For more Special Reports (Complete) data for DALAPON (6 total), please visit the HSDB record page.

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Dalapon is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0274; Pesticide type: herbicide; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Dalapon; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

These organic compounds donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acids dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in it to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

In case of fire in the surroundings, use appropriate extinguishing media.

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse skin with plenty of water or shower.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Give one or two glasses of water to drink. Do NOT induce vomiting. Refer for medical attention .

Excerpt from NIOSH Pocket Guide for 2,2-Dichloropropionic acid:

(General first aid procedures)

Extinguish with dry chemical, alcohol foam or carbon dioxide.

If material on fire or involved in fire: extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use water spray to knock-down vapors.

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. /Organochlorine pesticide, liquid/

If material on fire or involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Use "alcohol" foam, dry chemical or carbon dioxide. /Organochlorine pesticides, solid, toxic/

Spills of pesticides at any stage of their storage or handling should be treated with great care. Liquid formulations may be reduced to solid phase by evaporation. Dry sweeping of solids is always hazardous: These should be removed by vacuum cleaning or by dissolving them in water or other solvent in the factory environment. In the field, they may be washed away with water into a suitable soak-hole. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with a impermeable flexible membrane liner./ /Pesticides/

Environmental considerations: air spill: Apply water spray or mist to knock down vapors.

Environmental consideration: land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents.

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Use water spray to knock-down vapors. Neutralize spilled material with crushed limestone, soda ash, or lime.

For more Cleanup Methods (Complete) data for DALAPON (10 total), please visit the HSDB record page.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Dalapon-sodium can be incinerated in a unit with effluent gas scrubbing. Recommendable methods: Incineration, alkaline hydrolysis. /Dalapon sodium/

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. If liquid: collect leaking liquid in sealable containers as far as possible. If solid: sweep spilled substance into containers. Carefully collect remainder. Then store and dispose of according to local regulations.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Smoking, eating, drinking /and the use of toilet facilities/ before washing should be absolutely prohibited when any pesticide of moderate or higher toxicity is being handled or used. /Pesticides/

Handling and storage cautions: Do not contaminate water, food or feed by storage or disposal. Do not reuse spray equipment for any purpose unless thoroughly cleaned with a suitable cleaner. Do not reuse container; destroy when empty.

Personnel protection: Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. ... Do not handle broken packages unless wearing appropriate personal protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water.

For more Preventive Measures (Complete) data for DALAPON (12 total), please visit the HSDB record page.

Investigation of several derivatives ... has failed to reveal any with greater biological activity than sodium salt. ... Activity ... enhanced by changing pH or by adding any of several suitable surfactants. Latter alters physiologically important ionic & polar properties of dalapon solution.

Urinary

Eyes, skin, respiratory system, gastrointestinal tract, central nervous system

LC50 Daphnia pulex 11.0 mg/L/48 hr (95% confidence limit, 8.2-14.7) @ 15 °C; first instar. Static bioassay without aeration, pH 7.2-7.5, water hardness 40-50 mg/L as calcium carbonate and alkalinity of 30-35 mg/L.

LC50 Lepomis macrochiris (Bluegill) 105 mg/L/96 hr @ 24 °C; 1.0 g. Static bioassay without aeration, pH 7.2-7.5, water hardness 40-50 mg/L as calcium carbonate and alkalinity of 30-35 mg/L.

LC50 Pteronarcys >1,000 mg/L/96 hr @ 15 °C; first year class. Static bioassay without aeration, pH 7.2-7.5, water hardness 40-50 mg/L as calcium carbonate and alkalinity of 30-35 mg/L.

LC50 Simocephalus 16.0 mg/L/48 hr (95% confidence limit, 11.4-22.4) @ 15 °C; first instar. Static bioassay without aeration, pH 7.2-7.5, water hardness 40-50 mg/L as calcium carbonate and alkalinity of 30-35 mg/L.

For more Ecotoxicity Values (Complete) data for DALAPON (17 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), a reported Koc range of 1-2(2), indicates that dalapon is expected to have very high mobility in soil(SRC). The pKa of dalapon is 1.74(3), which indicates that this compound will exist predominantly as an anion in moist soils. Volatilization from moist soil surfaces will not occur since anions do not volatilize(SRC). Volatilization from dry soil surfaces is not expected to be an important environmental fate process(SRC) based on an estimated vapor pressure of 0.19 mm Hg determined from a fragment constant method(4). Biodegradation is expected to occur for dalapon at varying rates depending upon the conditions of the soil. The resultant average persistence of dalapon at recommended rates of application has been reported to be two to four weeks in most agricultural soils during the growing season(5). Under greenhouse conditions (28 °C), dalapon applied at a rate of 6 lbs/A persisted only 4-8 days in muck soil, 8-16 days in loam and silty loam soils, 16-32 days in sandy loam soil, and 32-64 days in silt clay soil(3). The half-life of dalapon in soil from Italy was reported as 30 days(6).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 1-2 in soil(2), indicate that dalapon is not expected to adsorb to suspended solids and sediment(SRC). The pKa of dalapon is 1.74(3), which indicates that this compound will exist primarily as an anion in water. Volatilization from water surfaces will not occur since anions do not volatilize(SRC). According to a classification scheme(4), a BCF of 3 measured in fish(3), suggests that bioconcentration in aquatic organisms is low(SRC). Hydrolysis is not expected to be an important fate process under environmental conditions since it has been concluded that dalapon and its salts have chemical hydrolytic half-lives of several months at temperatures less than 25 °C(3). Photolysis in sunlit surface waters may be possible since dalapon absorbs light greater than 290 nm(3); however, the rate of this potential reaction is not known in water. Dalapon has been shown to biodegrade in soils and sewage sludge under aerobic conditions(3), which suggests that it may also biodegrade in aerobic aquatic systems. The half-life of dalapon in anaerobic river sediment was 42 days, with complete degradation occurring at approximately 70 days(5).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dalapon, which has an estimated vapor pressure of 0.19 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase dalapon is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 29 days(SRC), calculated from its rate constant of 5.5X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). The UV absorption spectrum for dalapon shows absorbance in the range between 290 to 350 nm(4) which indicates that direct photolysis is possible, but the kinetics of this reaction are not known(SRC).

The substance can be absorbed into the body by inhalation and by ingestion.

inhalation, ingestion, skin and/or eye contact

... FED TO ANIMALS ... DALAPON RESIDUES REPORTED IN MILK WERE MUCH LESS THAN 1% OF AMT INGESTED IN FEED ... .

WHEN DAIRY COWS WERE FED DALAPON, LESS THAN 1% OF INGESTED DOSE APPEARED AS RESIDUES IN MILK, MAINLY AS UNCHANGED DALAPON BUT WITH TRACES OF DALAPON GLYCERIDES.

... /IT WAS/ FOUND ... IN MILK FROM COW WHOSE FEED CONTAINED (36)CHLORINE LABELED DALAPON.

/AQUATIC SPECIES/ Dalapon was among the compounds found to cause <10% mortality in catfish @ rate of 1 or 10 ppm.

/AQUATIC SPECIES/ Toxic concentrations of certain pesticides to mollusk Cerastoderma lamarcki are tabulated. Maximum permissible concentration of Dalapon is 0.01 mg/L.

/AQUATIC SPECIES/ In a comparative toxicology study on two fish species, Cyprinus carpio and Barbus sharpeyi, dalapon was nontoxic and no mortalites were detected up to 10,000 ppm.

/AQUATIC SPECIES/ Goldfish mortality at the end of 24 hr exposure to Dalapon was 0% at 100 ppm and 100% at 500 ppm and above.

For more Ecotoxicity Excerpts (Complete) data for DALAPON (6 total), please visit the HSDB record page.

Burning sensation. Cough. Sore throat.

Redness. Pain.

Redness. Pain. Blurred vision.

Burning sensation. Diarrhoea. Nausea. Vomiting.

irritation eyes, skin, upper respiratory system; skin burns; lassitude (weakness, exhaustion), loss of appetite, diarrhea, vomiting, slowing of pulse; central nervous system depression

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Dalapon is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA, as amended in 1988. Case No: 0274; Pesticide type: herbicide; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Dalapon; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5,000 lb or 2,270 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

2,2-Dichloropropionic acid is designated as a hazardous substance under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of this substance. This designation includes any isomers and hydrates, as well as any solutions and mixtures containing this substance.

(AZ) ARIZONA 560 ug/l

(ME) MAINE 200 ug/l

Two types of action: acute toxicity ... and slower growth inhibition. Acute toxicity ... due to its action as acid and protein precipitant which causes drastic permeability changes in plasma membranes and nonselective, localized destruction of cellular constituents. ... Toxic effects of dalapon at high rates are typical of those of strong acids, disrupting lipoidal membranes.

... the strongest inhibitors of NADH oxidase of the SMP are chloro-derivatives of aromatic hydrocarbons (DDT and its analogs DDD and DDE). Derivatives of propionic and acetic acids (propinate, dalapon, MCAA, DCAA, and TCAA) did not exhibit any appreciable inhibiting effect under the experimental conditions.

Pure (36)chlorine dalapon in aq stock solution was metabolized over a period of several mo in refrigerator by ... possibly Alternaria sp, which produced 5 new (36)chlorine labeled substances. Two of the substances were tentatively identified as inorganic (36)chlorine & (36)chlorine monochloropropionate.

Early labeled metabolic degradation products of 2-(14)carbon dalapon in presence of pure cultures of arthrobacter sp grown under aerobic conditions were pyruvate & alanine.

... Enzyme from Arthrobacter sp that removed organic bound chlorine from dalapon. ... Product resulting from enzymic dehalogenation ... was pyruvate. ... immediate precursor of pyruvate in this system is probably 2-chloro-2-hydroxypropionate.

Comparison of 1-(14)carbon dalapon and 2-(14)carbon dalapon metabolism /in mixed bacterial populations/ ... showed rapid evolution of (14)CO2 from carboxyl-labeled dalapon, whereas labeled carbon from 2 position ... was found primarily in lipid, nucleic acid, protein ... fractions of organisms. Study of soluble labeled products extracted from microorganisms incubated with (14)carbon dalapon showed activity in ... Alanine and glutamic acid.

...Dalapon is degraded in the environment or metabolized by organisms through dechlorination, dehydrochlorination, and oxidation to chloride ion, pyruvic acid (pyruvate), alanine, carbon dioxide, and other minor or intermediate transitory compounds.

In varying degrees, organochlorines are absorbed from the gut and also by the lung and across the skin. /Soild Organochlorines/

...Fed to animals... quickly excreted (nonmetabolized) in herbicidal concentrations in urine. ...Dalapon residues reported in milk were much <1% of amount ingested in feed... .

... /It was/ found... in milk from cow whose feed contained (36)chlorine labeled Dalapon.

When dairy cows were fed dalapon, <1% of ingested dose appeared as residues in milk, mainly as unchanged dalapon but with traces of dalapon glycerides.

For more Absorption, Distribution and Excretion (Complete) data for DALAPON (12 total), please visit the HSDB record page.

Selective herbicide; growth regulator; [HSDB]

No longer produced or used in the USA; [HSDB]

Farming (Pesticides) [Category: Industry]

The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

For dalapon (USEPA/OPP Pesticide Code: 028901) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./

In non-crop areas such as roadsides, railways, ditches. Also in certain established crops such as alfalfa, asparagus, flax, potatoes, rape seed, sugar beets.

... 2,2-Dichloropropionic acid can be made by chlorination of propionic acid, propionaldehyde, or propanol.

Dichloropropionic acid is produced by the direct chlorination of propionic acid in the presence of catalysts. Alkali salts are prepared by contacting 2,2-dichloropropionic acid with an essentially dry alkali compound of an alkali metal in a liquid chlorinated hydrocarbon as a reaction medium, and thereafter separating in its solid phase an alkali salt of 2,2-dichloropropionic acid.

The acid itself is not used directly. Commercial products usually contain 85% sodium salt or mixed sodium and magnesium salts of dalapon.

Dowpon C contains 46.7% dalapon sodium salt plus 7.8% dalapon magnesium salt plus 30.6% TCA (sodium salt) (discontinued by Dow). Chloropon is a mixture with 2,4-d. Revenge contains 46.7% dalapon sodium salt plus 7.8% dalapon magnesium salt plus 30.6% TCA sodium salt.

Dowpon C Improved Grass Killer: 46.7% 2,2-Dichloropropionic acid, sodium salt; 7.8% 2,2-Dichloropropionic acid, magnesium salt; 30.6% Trichloroacetic acid, sodium salt; 14.9% inert ingredients.

Dowpon Grass Killer; 85% sodium 2,2-dichloropropionate.

For more Formulations/Preparations (Complete) data for DALAPON (7 total), please visit the HSDB record page.

Propanoic acid, 2,2-dichloro-: ACTIVE

Dalapon ... should be used within 24 hr after mixing with water ... .