Maleic hydrazide

112.09

112.09

112223

204-619-9

TQ7L3FCV66

48832|13892|8823

3082|3077

DTXSID9020792

Crystals from water|COLORLESS CRYSTALLINE SOLID

29339990

58.2

-1.96at pH=7;-2.41at pH=9

Maleic hydrazide is an odorless white solid. Sinks in water. (USCG, 1999)

1.60 g/cm³ @ Temp: 25 °C

298-300 °C

Decomposes (NTP, 1992)

300°C

1.640

H2O: 6 g/L

0-6°C

7.5X10-8 mm Hg at 25 deg C

Oral-Rat LD50: 3000 mg/kg

Combustion produces toxic nitrogen oxide gas

Combustible

Odorless

Henry's Law constant = 8.1X10-9 atm-cu m/mol at 25 °C and pH 7

pKa = 5.62 at 20 °C

Decomposes @ 260 °C|Forms water-soluble alkali-metal and amine salts, but, in hard water, the calcium salt is precipitated.|Hydroxyl radical reaction rate constant 1.3X10-11 cu cm/molec-sec at 25 °C /Estimated/

Insoluble in water.

Amides and Imides

MALEIC HYDRAZIDE can be decomposed by oxidizing agents. It can also be decomposed by strong acids. It forms water-soluble alkali-metal and amine salts. It is slightly acidic and may be titrated as a monobasic acid. Mild oxidation produces a compound which reacts instantly with dienes at -107° F to form crystalline derivatives. This chemical is slightly corrosive to iron and zinc. It is incompatible with pesticides that are highly alkaline in reaction. In the presence of heavy metal and iron, zinc, calcium and magnesium ions, sparingly-soluble salts are formed. (NTP, 1992)

-8,200 BTU/LB= -4,500 CAL/G= -190X10+5 J/KG (EST)

Liquid formulated products are corrosive to brass nozzles if sprayed undiluted.

UN 3077 9/PG 3

2

36/37/38-40-R40-R36/37/38-68

26-36-45-36/37/39-S45-S36/37/39-S26

UR5950000

Xi,Xn

The warehouse is ventilated, low temperature and dry; stored and transported separately from food materials

Degraded by light.

P261-P281-P305 + P351 + P338

H315-H319-H335-H341

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U148, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.|Maleic hydrazide is a potential candidate for rotary kiln incineration with a temperature range of 820 to 1600 °C and residence times of seconds for liquids and gases, hours for solids. Also, a potential candidate for fluidized bed incineration range of 450 to 980 °C with residence times of seconds for liquids and gases, longer for solids.|This product is relatively stable to hydrolysis but decomposes in presence of strong acids and oxidizing agents.

If in presence of strong acid, maleic hydrazide acid may precipitate. Do not use concentrate through brass nozzles as the amine content may cause erosion.|Incompatible with pesticides which are highly alkaline in reaction.|Stable to hydrolysis but decomposed by concentrated oxidizing acids with the evolution of nitrogen.|In the presence of heavy-metal and iron, zinc, calcium and magnesium ions, sparingly-soluble salts are formed.

DOLNICKI A; WIAD BOT 23 (2): 59-72 (1979). A REVIEW WITH APPROX 200 REFERENCES ON TAUTOMERIC FORMS OF MALEIC HYDRAZIDE AND THEIR ACTION ON PLANTS.|USEPA/Office of Pesticide Programs; Reregistration Eligibility Decision Document - Maleic Hydrazide EPA 738-R-94-010 June 1994. The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of July 1, 2004: http://www.epa.gov/pesticides/reregistration/status.htm]|California Environmental Protection Agency/Department of Pesticide Regulation; Toxicology Data Review Summaries. Available from: http://www.cdpr.ca.gov/docs/toxsums/toxsumlist.htm on Maleic Hydrazide as of July 21, 2004

Special Hazards of Combustion Products: Toxic nitrogen oxides are produced. (USCG, 1999)

|Warning|H315 (100%): Causes skin irritation [Warning Skin corrosion/irritation]|P201, P202, P261, P264, P271, P280, P281, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, and P501|Aggregated GHS information provided by 76 companies from 5 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above. FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)

SMALL SPILLS AND LEAKAGE: If you spill this chemical, dampen the solid spill material with 5% ammonium hydroxide, then transfer the dampened material to a suitable container. Use absorbent paper dampened with 5% ammonium hydroxide to pick up any remaining material. Your contaminated clothing and the absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Wash all contaminated surfaces with 5% ammonium hydroxide followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned. STORAGE PRECAUTIONS: You should store this material under ambient temperatures, and keep it away from oxidizing materials and strong acids. (NTP, 1992)

Goggles or face shield; dust mask. (USCG, 1999)|Goggles or face shield; NIOSH-certified respirator.|...Vinyl coated hand protection, natural or reclaimed rubber protection, rubber aprons, and plastic eye and face protection... used when working with small quantities. Where possibility of gross splashing exists, full protective clothing made of rubber, neoprene or vinyl-coated materials should be worn. For respiratory protection in situations where recommended tolerance limits... exceeded, respiratory protective equipment... must be used. /Hydrazine and derivatives/

Combustible

Extinguish with water, dry chemicals, foam or carbon dioxide.

Ventilate area of spill or leak. Collect for reclamation, or absorb in vermiculite, dry sand, earth, or a similar material.|Spillages 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/

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.|SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.|Recommended method of cleaning glassware and spray equipment: Formulation completely water soluble, wash and rinse equipment with water.|Personal safety precautions: Remove contaminated clothing and shoes.|Smoking, eating, drinking, /and using toilet facilities/ before washing should be absolutely prohibited when any pesticide of moderate or higher toxicity is being handled or used. /Pesticides/

Dust from or contact with the material is irritating to eyes, nose, throat, and skin.

U148; A toxic waste when a discarded commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or manufacturing chemical intermediate.

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).

U148; As stipulated in 40 CFR 261.33, when maleic hydrazide, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).

Maleic hydrazide has been tentatively identified in advanced waste treatment water from Orange County, CA(1).

PERSISTS IN SOIL FOR PERIOD OF 4-10 WK.

Average maleic hydrazide residues of 50 and 100 ppm were found in tobacco by the Department of Agriculture; in rare cases, residues >500 ppm were found(1).

moderately

Pretreatment of Vicia faba root tip meristems with a nontoxic dose of either hydrazine or N,N'-diformylhydrazine prior to the administration of maleic hydrazide (MH), separated by 2 hr, resulted in a significant reduction of the yield of MH induced chromatid aberrations compared to control treatments (MH only). Pretreatment with the hydrazines induces an error free repair system which reduces MH induced damage and both hydrazines and MH appear able to induce oxidative DNA lesions.|Root tip cells of Allium cepa were exposed to maleic hydrazide (0.0003 M for 2 hr) and post-treated in G2 with caffeine (2.5 mM) and various inhibitors of DNA synthesis. No enhancement of chromosome damage was observed when caffeine was present in G2, but hydroxyurea (5 mM) or 5-fluorodeoxyuridine (1x10-7 M) potentiated the frequencies of chromosome aberrations. A slight additional incr of chromosome aberration frequencies was observed following treatment with Ara C (1x10-5 M) and excess thymidine in G2. When maleic hydrazide damaged cells were pulse treated with caffeine earlier during recovery, the yield of chromosomal aberrations was enhanced. The earlier caffeine was present following maleic hydrazide treatment, the stronger was the potentiation.|Conditioning treatment of Vicia faba root tip meristem cells with nickel chloride prior to challenge treatment with triethylenemelamine or maleic hydrazide triggered protective functions against both these clastogens, i.e., resulted in a significantly reduced yield of metaphases with chromatid aberrations. Protection was prevented by pretreatment with buthionine sulfoximine, an inhibitor of the synthesis of plant phytochelatins, indicating that the nickel chloride triggered phytochelatin synthesis may be involved in the protective functions induced by nickel chloride conditioning treatment. Buthionine sulfoximine (instead of nickel chloride) conditioning treatment triggered protection against maleic hydrazide but not against triethylenemelamine.|Pretreatment of Vicia faba main root meristems with ethidium bromide or nalidixic acid significantly reduced the yield of metaphases with chromatid aberrations induced by maleic hydrazide, ie, triggered clastogenic adaptation to maleic hydrazide. No such protection occurred when the alkylating agent triethylenemelamine was used for challenge treatment. The differential response of pretreated cells to maleic hydrazide on the one hand (protection) and to triethylenemelamine (no protection) on the other supports the conclusion that clastogenic adaptation is due to different inducible (repair) functions, which eventually exert protection against clastogenic impacts.

LD50 Rat oral >5000 mg/kg|LD50 Rabbit percutaneous >5000 mg/kg|LD50 Rat oral 5800 mg/kg bw /Maleic hydrazide, sodium salt/|LD50 Rat oral 3900 mg/kg /Maleic hydrazide, potassium salt/|For more Non-Human Toxicity Values (Complete) data for MALEIC HYDRAZIDE (7 total), please visit the HSDB record page.

/AQUATIC SPECIES/ No mortality at 10.0 ppm to bluegills and fatheads.

Biological half-lives were significantly different among the three acetylation phenotypes (analysis of variance, P < 0.05): 3.94+/-1.70 hours for slow acetylators, 2.25+/-0.37 hours for intermediate acetylators, and 1.86+/-0.67 hours for rapid acetylators. /Hydrazine/

Maleic hydrazide is not known to occur as a natural product(1).

Maleic hydrazide's production may result in its release to the environment through various waste streams; it's use as an herbicide and sprout inhibitor(1) will result in its direct release to the environment(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), measured Koc values of 264 for a clay soil, and 23 for a sandy loam(2), indicate that maleic hydrazide is expected to have very high to moderate mobility in soil. Maleic hydrazide exists in equilibrium with its tautomer 6-hydroxy-3(2H)-pyridazinone that has a pKa of 5.62(2), which indicates that this compound will primarily exist as an anion in moist soils and anions do not volatilize. The neutral species of maleic hydrazide is not expected to volatilize based on a Henry's Law constant of 8.1X10-9 atm-cu m/mole(2). Maleic hydrazide is not expected to volatilize from dry soils(SRC) based on a vapor pressure of 7.5X10-8 mm Hg at 25 °C(2). Biodegradation has been shown to be an important environmental fate process for maleic hydrazide in soils(2). The half-life of maleic hydrazide was reported as 2-3 days in a sandy loam used for growing potatoes, 6 days in a turfed sandy loam, and 7 days in a tobacco growing loam(2).|AQUATIC FATE: Based on a classification scheme(1), measured Koc values of 264 for a clay soil, and 23 for a sandy loam(3), indicates that maleic hydrazide is not expected to adsorb to suspended solids and sediment(SRC). Maleic hydrazide exists in equilibrium with its tautomer 6-hydroxy-3(2H)-pyridazinone that has a pKa of 5.62(2), which indicates that this compound will primarily exist as an anion in water and anions do not volatilize. The neutral species of maleic hydrazide is not expected to volatilize based on a Henry's Law constant of 8.1X10-9 atm-cu m/mole(3). According to a classification scheme(4), an estimated BCF of 3(SRC), from a log Kow of -1.96(3) and a regression-derived equation(5), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Maleic hydrazide is stable to hydrolysis, but may undergo photochemical decomposition in sunlit surface waters(6). Maleic hydrazide (as the potassium salt) was irradiated with simulated sunlight in aqueous solutions at pH 5, 7 and 9 with calculated half-lives of 58, 58 and 34 days, respectively(6). The major product was maleate(6). Based on the rapid rate of biodegradation in soil(7), maleic hydrazide is expected to biodegrade in water under aerobic conditions.|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), maleic hydrazide, which has a vapor pressure of 7.5X10-8 mm Hg at 25 °C(2), is expected to exist primarily in the particulate phase. Particulate-phase maleic hydrazide may be removed from the air by wet and dry deposition(SRC). Although maleic hydrazide absorbs light greater than 290 nm and photolyzes in aqueous solution(3), it exists primarily in the particulate phase in the atmosphere and it is unclear whether direct photolysis will be an important environmental fate process(SRC).

Maleic hydrazide is stable to hydrolysis(1,2), but can undergo photochemical decomposition(2,4). Aqueous solutions (in the presence of oxygen) of maleic hydrazide were destroyed completely after approximately 48 hours irradiation through a Pyrex filter with UV light at >290 nm(4,5). The volatile products of this photolysis reaction were nitric acid (12.5% yield) and formic acid (7.5% yield)(4). More than 15 other non-volatile products were observed, including succinic acid (11.8% yield), maleic acid (8.3% yield), and fumaric acid (22.6% yield)(4). Maleic hydrazide, in water, strongly absorbs UV light in the environmentally significant range (wavelength >290 nm) and has an absorption maximum at approximately 300 nm(3). Maleic hydrazide was stable to simulated sunlight at pH5 and 7 at 25 °C over a 30-day exposure period. It degraded slowly at pH 9 and 25 °C, with a calculated half-life of 15.9 days and a rate constant of 0.0435 day-1(6). At pH 7 and 9, the maleic hydrazide would be present largely as the anion. The degradation products at pH 9 were maleate and succinate. Starting with potassium maleic hydrazide salt, photolysis of aqueous solutions at pH 5, 7 and 9 produced calculated half-lives of 58, 58 and 34 days, respectively. The major product was maleate(6).|IN PRESENCE OF OXYGEN, MH UNDERGOES PHOTOLYSIS TO FORM SUCCINIC, MALEIC AND NITRIC ACID; AND IN ABSENCE OF OXYGEN ... SUCCINIC ACID.|MALEIC HYDRAZIDE APPLIED TO TOBACCO UNDERGOES THERMAL DEGRADATION TO ISOCYANIC ACID. IN MODEL PYROLYSIS STUDIES, ETHANOL & METHANOL REACT WITH ISOCYANIC ACID TO GIVE ETHYL & METHYL CARBAMATES /WHICH ARE MUTAGENIC/.|Pyrolysis of maleic hydrazide at 900 °C produced a variety of organic compounds: carbon monoxide, carbon dioxide, benzene, acrylonitrile, acetonitrile, propionitrile, toluene, cyanopropene(s), cyanobutadiene(s), styrene, 2-vinylpyridine, pyrrole, indene, benzonitrile, dicyanoethylene, cyanotoluene(s), aniline, naphthalene, quinoline, benzylcyanide, 2-methylnaphthalene, 1-methylnaphthalene, and pyridine.|The rate constants for the vapor-phase reactions of maleic hydrazide with photochemically produced hydroxyl radicals and ozone have been estimated to be 1.33X10-11 cu cm/molec sec and 1.75X10-16 cu cm/molec sec at 25 °C(SRC) using a structure estimation method(1). These rate constants correspond to half-lives of 29 hrs, and 6.5 days, respectively for these processes at an atmospheric concn of 5X10+5 hydroxyl radicals/cu cm and 7X10+11 ozone molecules/cu cm(2,3). These vapor-phase reactions may not be major removal pathways in the atmosphere; however, since the compound will be expected to be almost entirely in the particulate phase based upon its very low vapor pressure(SRC).

An estimated BCF of 3 was calculated for maleic hydrazide(SRC), using a log Kow of -1.96 (1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

2.82 L/kg|The reported Koc of maleic hydrazide was 264 for a clay soil, and 23 for a sand(1). Based on a classification scheme(2), these Koc values suggest that maleic hydrazide has very high to moderate mobility in soil(SRC). In a field experiment in which 5 and 10 kg/ha of maleic hydrazide were applied, the hydrazide did not migrate below a depth of 10 cm(3). This may be due to extensive biodegradation of maleic hydrazide(3). Maleic hydrazide was shown to bind to the clay component in Aiken clay loam where anion exchange is the predominant process(4). In a study of the adsorption of maleic hydrazide in 22 different soils, adsorption was most significantly correlated to specific surface area, clay content, and pH(5). The lack of correlation of adsorption with organic content of the soils may have been partly caused by the low organic content of the soils studied (<2%)(5). Adsorption of the herbicide ranged from high to low(5). Based upon the above information, maleic hydrazide may generally be expected to be mobile in soils with low clay content and relatively immobile in soils with high clay content. The mobility also may be affected by pH and specific surface area of the soils(SRC).

Maleic hydrazide, which exists in equilibrium with its tautomer 6-hydroxy-3(2H)-pyridazinone, has a pKa of 5.62(1), which indicates that this compound will primarily exist as an anion in water and moist soil surfaces and anions do not volatilize. The Henry's Law constant for maleic hydrazide is 8.1X10-9 atm cu m/mol at 25 °C , pH 7(1). This Henry's Law constant indicates that the neutral species of maleic hydrazide is expected to be essentially nonvolatile from water and moist soil surfaces(2). Maleic hydrazide is not expected to volatilize from dry soils(SRC), based a vapor pressure of 7.5X10-8 mm Hg at 25 °C(1).

DRINKING WATER: Maleic hydrazide has been tentatively identified in drinking water from Cincinnati OH(1).

Maleic hydrazide was detected in 14.2% of onion samples tested, with a max concn of 0.559 ppm during a survey of foods in Belgium(1). Maleic hydrazide was detected in approximately 25% of commercially purchased potato chips, at a max concn of 0.3 ug/g(2). Maleic hydrazide was identified, not quantified, in unspecified food items during a 1978-1982 FDA monitoring study of domestic and imported food commodities(3).

HUMAN POPULATIONS MAY BE EXPOSED TO MALEIC HYDRAZIDE BY INHALATION WHEN SUBSTANCE IS SPRAYED FOR AGRICULTURAL & HORTICULTURAL PURPOSES, & BY INTAKE WITH FOOD ... .|NIOSH (NOES Survey 1981-1983) has statistically estimated that 1442 (none are female) workers are exposed to maleic hydrazide in the USA(1). This survey does not include pesticide applicators and harvesters so actual exposure potential may be greater(SRC). The general population is exposed to maleic hydrazide through ingestion of food items and inhalation of tobacco smoke containing this compound(SRC). In the field, two groups of workers, the applicators and harvesters, were exposed to maleic hydrazide(2). Dermal exposure rates to maleic hydrazide at various body locations on applicators averaged between 105-711 ug/hr for 4 operators of high-clearance tractors and 324-4332 ug/hr for 3 operators of low clearance tractors(2). The average rate of respiratory exposure was 0.74 ug/hr and 10 ug/hr for high clearance and low clearance operators, respectively(2).

Average levels of maleic hydrazide in urine samples of 7 applicators, 0-36 hours following exposure, ranged from <0.03 to 0.28 ppm(1).

Pesticides used to destroy unwanted vegetation, especially various types of weeds, grasses (POACEAE), and woody plants. Some plants develop HERBICIDE RESISTANCE. (See all compounds classified as Herbicides.)|Any of the hormones produced naturally in plants and active in controlling growth and other functions. There are three primary classes: auxins, cytokinins, and gibberellins. (See all compounds classified as Plant Growth Regulators.)

...After oral doses of 100 mg/kg bw, rabbits excreted 43 to 62% maleic hydrazide unchanged in urine within 48 hr.|(14)C Maleic hydrazide was administered orally to rats. After 3 days, very little (14)C activity was detected in tissues or blood and carbon dioxide accounted for only 0.2% of administered dose. Maleic hydrazide was rapidly excreted via urine unchanged (>90%) and as conjugate (6-8%).|Slowly absorbed over period of 24 hr by quackgrass. Rain within this period will reduce effectiveness. Rate of absorption is function of cell turgidity. Most effective absorption occurs when soil moisture is at field capacity and relative high humidity. Translocates more effectively downward. Once absorbed, maleic hydrazide is freely translocated to active growing points in plant. maleic hydrazide becomes fixed within the plant and is not metabolized.|In white ash and black locust seedlings, most of maleic hydrazide was translocated to leaves and stems of black locust seedlings within 1 day after treatment, but for white ash seedlings it remained in the stem tissue. After 30 days, the (14)C was concentrated in the leaves of the black locust seedlings, but only in the stem and at the injection point of white ash seedlings. Chromatography of the extracts showed no detectable metabolite in black locust seedlings, but 2 metabolites were detected in the white ash seedlings.|For more Absorption, Distribution and Excretion (Complete) data for MALEIC HYDRAZIDE (10 total), please visit the HSDB record page.

When applied to tea, Camelia sinensis, MH /(maleic hydrazine)/ was degraded to lactic acid, succinic acid, maleimide and hydrazine. Extracts of treated wheat seedlings... identified... beta-glycoside of MH. ...In presence of oxygen, MH undergoes photolysis to form succinic, maleic and nitric acid; and in absence of oxygen... succinic acid.|When applied to silver maple... and American sycamore... seedlings, maleic hydrazide translocated to all parts of the plant. In the plant tissue, a metabolite was formed. Hydrolysis products of the metabolite indicated a conjugate of maleic hydrazide and glucose. When applied to tobacco plants, (14)C maleic hydrazide was rapidly translocated to growing tissues. Translocation to roots also occurred. A small amount of (14)CO2 evolved. The major metabolite in foliar tissues was identified as the beta-D-glucoside of maleic hydrazide.|In one radio label experiment in rats, 77% of the administered radioactivity was recovered in urine within 6 days. 90% of the activity was found to be unaltered maleic hydrazide. The remainder was present as a conjugate of MH.|In rats, the urine and feces samples /collected following oral administration of 3,6-dione-labelled 14C-maleic hydrazide/ contained two peaks. Poor chromatographic separation and low levels of radiolabel in the fecal samples precluded reliable identification, but the peaks appeared to represent maleic hydrazide and possibly fumaric acid. The major peak in urine, representing 60% of the urinary radiolabel in males and 80% in females, co-chromatographed with maleic hydrazide. The minor urinary peak was initially found to co-chromatograph with maleimide, fumaric acid, or maleic diamide, depending on the solvent system, but subsequent investigation with deconjugation with a beta-glucuronidase containing sulfatase activity and HPLC showed this peak to be a maleic acid conjugate, probably a sulfate.|For more Metabolism/Metabolites (Complete) data for MALEIC HYDRAZIDE (7 total), please visit the HSDB record page.

Maleic hydrazide inhibits mitosis in actively growing tissues of treated plants and also has profound effects on rate of respiration. ... Maleic acid ... reacts with -SH compounds ... /and/ competes with receptor sites of ... succinic dehydrogenase. ... Inhibition ... may represent site of action ... in plants.

Technical grade maleic hydrazide contains hydrazine as a contaminant.|Products can contain small amount of hydrazide as impurity.

Inhalation of dust causes irritation of nose and throat. Contact with eyes or skin causes irritation. Ingestion has been observed to cause tremors and muscle spasms in test animals. (USCG, 1999)

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment. INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing. INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Cover skin burns with dry, sterile dressings after decontamination ... . /Hydrazine and Related Compounds/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors for hypotension with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam ... . Monitor for signs of hypoglycemia (decreased level of consciousness, tachycardia, pallor, dilated pupils, diaphoresis, and/or a dextrose strip or glucometer reading less than 50 mg/dl) and administer 50% dextrose if necessary. Draw blood sample before administration ... . Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen. ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Hydrazine and Related Compounds/|Specific treatment for exposure consists of thorough washing of all exposed skin areas with soap and water, copious irrigation of the eyes, and prompt removal of the patient from the source of exposure. /Hydrazines/|After inhalation, observation for progressive respiratory distress is necessary. Chest X-ray and arterial blood gases should be monitored. Administration of oxygen, intubation, and assisted ventilation may become necessary. Pneumonia and bronchitis need to be excluded. /Hydrazines/|For more Antidote and Emergency Treatment (Complete) data for MALEIC HYDRAZIDE (6 total), please visit the HSDB record page.

/HUMAN EXPOSURE STUDIES/ Because maleic hydrazide is used as a herbicide, spray applications were tested to determine the extent of absorption following contact during actual use periods. The authors concluded that the applicators, whether they used high- or low-clearance tractors, were not at risk of developing maleic hydrazide-induced toxicity. Similar conclusions were reached when hand harvesters were studied. The absence of detectable residues in urine, despite established dermal and respiratory exposure, indicates minimal absorption by hand harvesters.

Acid Hydrazide, Maleic

Plant growth regulator for tobacco, 90%; for potatoes & onions, 10% (1983 est)

Maleic hydrazide is available as technical grade material containing 97% min a.i. and less than 1% anionic wetting agent. It is also offered for sale as EC or WP for agricultural uses in form of its potassium salt or its diethanolamine salt. Products can contain small amount of hydrazine as impurity.|MH-30: diethanolamine salt contains 3.5 lb maleic hydrazide/imp gal. Used at 9.5-0.25% maleic hydrazide as herbicide; 0.1-0.5% as growth inhibitor and 0.025% to prevent pollen germination as 4-6 lb/acre for chemical grass mowing.|Combinations: BH 43 (with 2,4-D)|Water-soluble liquids|For more Formulations/Preparations (Complete) data for MALEIC HYDRAZIDE (22 total), please visit the HSDB record page.

3,6-Pyridazinedione, 1,2-dihydro-: ACTIVE|T - indicates a substance that is the subject of a final TSCA section 4 test rule.|... Is not effective through soil application.|All uses of the diethanolamine salt in the United States were suspended on October 31, 1981, but the material may be manufactured for export and growers may use any material still on hand. /Maleic hydrazide diethanolamine salt/

Reduce and hydrolyze to give hydrazine which is distilled off and estimated colorimetrically using p-dimethylaminobenzaldehyde.|Small amounts of hydrazine were detected in maleic hydrazide formulations by a method involving derivative formation with pentafluorobenzaldehyde, extracting the pentafluorobenzaldehyde azine with hexane and determining by glc with ecd. Recoveries of 72-80% were obtained from samples fortified with 1 and 10 ug of hydrazine. Limit of detection was 0.05 mg/kg.|Small amt (less than 1 ppm) of mh /(maleic hydrazine)/ in plant and animal tissues can be estimated photometrically ... . It may also be determined in extracts from tobacco smoke by GC.|Product analysis is by differential titration; residues may be determined by hydrolysis to hydrazine which is determined by colorimetry.|For more Analytic Laboratory Methods (Complete) data for MALEIC HYDRAZIDE (10 total), please visit the HSDB record page.

Agrochemicals -> Plant Growth Regulators|Herbicides, Plant growth regulators|Environmental transformation -> Pesticide transformation products (metabolite, successor)

Maleic hydrazide is a known environmental transformation product of Linuron.