1-Methylcyclopropene

54.09

54.09

J6UJO23JGU

DTXSID2035643

Gas

2902199011

0

2.03 (est)

0.8±0.1 g/cm3

75-76 °C

8 °C

-72.5±6.6 °C

1.474

In water, 725.8 mg/L at 25 deg C (est)

570 mm Hg at 25 deg C (est)

Henry's Law constant = 4.44X10-12 atm-cu m/mol at 25 °C (est)

Hydroxyl radical reaction rate constant = 8.70X10-11 cu cm/molec-sec at 25 °C (est)

P210, P260, P271, P284, P304+P340, P310, P320, P377, P381, P403, P403+P233, P405, P410+P403, P501

H220

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.

Not Classified

Applicators of this product must wear: Long-sleeved shirt and long pants, Shoes plus socks, Chemical-resistant gloves made of any waterproof material.|AGRICULTURAL USE REQUIREMENTS. Use this product only in accordance with its labeling and with the Workers Protection Standard, 40 CFR Part 170. ... The requirements in this /entry/ only apply to uses of this product that are covered by the Worker Protection Standard. Do not enter or allow worker entry into treated areas prior to venting the volatile active ingredient from the treatment room. PPE required for early entry to treated areas that is permitted under the Worker Protection Standard and that involves contact with anything that has been treated, such as plants, soil or water, prior to venting the volatile active ingredient from the treatment room is: Coveralls, Chemical-resistant gloves made of any waterproof material, Shoes plus socks, Respirator.

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.|Applicators and handlers must follow manufacturer's instructions for cleaning and maintaining PPE. If no such instructions exist for washables, use detergent and hot water. Keep and wash PPE separately from other laundry.|Causes slight eye irritation. Harmful if absorbed though skin. Avoid contact with eyes, skin or clothing. Avoid breathing vapor. Wash thoroughly with soap and water after handling. Remove contaminated clothing and wash before reuse.|FIRST AID. IF IN EYES: Flush with plenty of water for at least 15 minutes. Call a physician if irritation persists. IF ON SKIN: Wash with plenty of soap and water. Get medical attention. IF INHALED: Remove victim to fresh air. If not breathing, give artificial respiration ... . Get medical attention. IF SWALLOWED: Dilute by drinking 1 or 2 glasses of water and call a physician.

Causes slight eye irritation.

LD50 Rat (albino) oral >5000 mg/kg /EthylBloc, powdered product/|LD50 Rabbit (albino) dermal >2000 mg/kg /EthylBloc, powdered product/|LC50 Rat (albino) inhalation (4hr) >165 ppm /1-MCP gas/

1-Methylcyclopropene's production may result in its release to the environment through various waste streams; its use as a plant growth regulator to extend the life of cut and potted flowering, and other greenhouse plants(1) may result in its direct release to the environment(SRC) although this use is in confined spaces(1).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 43(SRC), determined from a structure estimation method(2), indicates that 1-methylcyclopropene is expected to have very high mobility in soil(SRC). Volatilization of 1-methylcyclopropene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.4X10-2 atm-cu m/mole(SRC), using a fragment constant estimation method(3). 1-Methylcyclopropene is expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 570 mm Hg(SRC), determined from a fragment constant method(4). Biodegradation data were not available(SRC, 2007).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 42(SRC), determined from a structure estimation method(2), indicates that 1-methylcyclopropene is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected to be an imporant environmental fate process(3) based upon an estimated Henry's Law constant of 4.4X10-2 atm-cu m/mole(4)(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2 hours and 3 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 7(SRC), from an estimated log Kow of 2.03(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data were not available(SRC, 2007).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1-methylcyclopropene, which has an estimated vapor pressure of 570 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a gas in the ambient atmosphere. Gas-phase 1-methylcyclopropene 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 4 hours(SRC), calculated from its rate constant of 8.7X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Gas-phase 1-methylcyclopropene is degraded in the atmosphere with ozone(SRC); the half-life for this reaction is 38 minutes, calculated from its rate constant of 4.3X10-16 cu cm/molecule-sec at 25 °C(SRC) that was dervied using a structure estimation method(3). 1-Methylcyclopropene does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of 1-methylcyclopropene with photochemically-produced hydroxyl radicals has been estimated as 8.7X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 4 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of 1-methylcyclopropene with ozone has been estimated as 4.3X10-16 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(1). This corresponds to an atmospheric half-life of about 38 minutes at an atmospheric concentration of 7X10+11 ozone molecules per cu cm(2). 1-Methylcyclopropene is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 1-Methylcyclopropene does not contain chromophores that absorb at wavelengths >290 nm(3) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 7 was calculated in fish for 1-methylcyclopropene(SRC), using an estimated log Kow of 2.03(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), provided the compound is not metabolized by the organism(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 1-methylcyclopropene can be estimated to be 43(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1-methylcyclopropene is expected to have very high mobility in soil.

The Henry's Law constant for 1-methylcyclopropene is estimated as 4X10-2 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 1-methylcyclopropene is expected to volatilize rapidly from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 2 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 3 days(SRC). 1-Methylcyclopropene's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 1-Methylcyclopropene is expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 570 mm Hg(SRC), determined from a fragment constant method(3).

Occupational exposure to 1-methylcyclopropene may occur through inhalation and dermal contact with this compound at workplaces where 1-methylcyclopropene is produced or used(SRC). 1-Methylcyclopropene's use is in confined spaces(1).

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.)

1-MCP has a mode of action in plants which is a non-persistent and non-toxic mode of action. 1-MCP prevents the natural chemical, ethylene, from binding to ethylene receptors in plants. This mode of action is not relevant in animals, since ethylene receptors are not present in animal tissues.|It was first noted that 2, 5-norbornadiene seemed to counteract ethylene. Studies showed it was a competitive inhibitor of ethylene responses, and knowledge that ethylene antagonists like ethylene agonists bound to silver in the same order as they were active as inhibitors was obtained. Ring strain appeared to be a primary factor that led to trans-cyclooctene then to diazocyclopentadiene. This same concept allowed for the use of chemical concepts that lead to cyclopropenes. More recent work indicates additional factors can come into play in the development of ethylene antagonists at the receptor level and these are now being utilized to find additional and improved antagonists. 1-MCP is likely to remain a primary means of controlling ethylene responses for the immediate future.|Volatile esters are major aroma components of apple, and an alcohol acyltransferase (AAT) catalyzes the final step in ester biosynthesis. The gene MdAAT2, which encodes a predicted 51.2 kDa protein containing features of other acyl transferases, was isolated from Malus domestica Borkh. (cv. Golden Delicious). In contrast to other apple varieties, the MdAAT2 gene of Golden Delicious is exclusively expressed in the fruit. The MdAAT2 protein is about 47.9 kDa and mainly localized in the fruit peel, as indicated by immunoblot and immunolocalization analysis. Northern blot and immunoblot analysis showed that the transcription and translation of MdAAT2 have a positive correlation with apple AAT enzyme activity and ester production, except in the later ripening stage, suggesting that MdAAT2 is involved in the regulation of ester biosysthesis and that a post-translation modification may be involved in regulation of AAT enzyme activity. Tissue disk assays of fruit peel revealed that using extraneous alcohols can recover the corresponding ester formation. Transcription and translation of MdAAT2 were both depressed by 1-methylcyclopropene (1-MCP) treatment and subsequent ester production was also prevented. These results suggest that: (1) ester production is mainly regulated by MdAAT2; (2) ethylene is also involved in this regulatory progress and (3) ester compounds rely principally on the availability of substrates.|By screening for ethylene response mutants in Arabidopsis, a novel mutant, eer2, was isolated which displays enhanced ethylene responses. On a low nutrient medium (LNM) light-grown eer2 seedlings showed a significant hypocotyl elongation in response to low levels of 1-amino-cyclopropane-1-carboxylate (ACC), the precursor of ethylene, compared with the wild type, indicating that eer2 is hypersensitive to ethylene. Treatment with 1-MCP (1-methylcyclopropene), a competitive inhibitor of ethylene signalling, suppressed this hypersensitive response, demonstrating that it is a bona fide ethylene effect. By contrast, roots of eer2 were less sensitive than the wild type to low concentrations of ACC. The ethylene levels in eer2 did not differ from the wild type, indicating that ethylene overproduction is not the primary cause of the eer2 phenotype. In addition to its enhanced ethylene response of hypocotyls, eer2 is also affected in the pattern of senescence and its phenotype depends on the nutritional status of the growth medium. Furthermore, linkage analysis of eer2 suggests that this mutant defines a new locus in ethylene signalling.|Auxin, which has been implicated in multiple biochemical and physiological processes, elicits three classes of genes (Aux/IAAs, SAURs and GH3s) that have been characterized by their early or primary responses to the hormone. A new GH3-like gene was identified from a suppressive subtraction hybridization (SSH) library of pungent pepper (Capsicum chinense L.) cDNAs. This gene, CcGH3, possessed several auxin- and ethylene-inducible elements in the putative promoter region. Upon further investigation, CcGH3 was shown to be auxin-inducible in shoots, flower buds, sepals, petals and most notably ripening and mature pericarp and placenta. Paradoxically, this gene was expressed in fruit when auxin levels were decreasing, consistent with ethylene-inducibility. Further experiments demonstrated that CcGH3 was induced by endogenous ethylene, and that transcript accumulation was inhibited by 1-methylcyclopropene, an inhibitor of ethylene perception. When over-expressed in tomato, CcGH3 hastened ripening of ethylene-treated fruit. These results implicate CcGH3 as a factor in auxin and ethylene regulation of fruit ripening and suggest that it may be a point of intersection in the signaling by these two hormones.

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/|Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... Monitor for shock and treat if necessary ... Anticipate seizures and treat if necessary ... For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) 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 ... Cover skin burns with dry sterile dressings after decontamination ... /Poisons A and B/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

/OTHER TOXICITY INFORMATION/ The overall toxicological risk from human exposure to 1-MCP is considered negligible.

1-MCP

ETHYLBLOC Active Ingredient 0.140% Cyclopropene,1-methyl|ETHYLBLOC SACHET Active Ingredient 0.014% Cyclopropene,1-methyl-|MANUFACTURING-USE-PRODUCE - SF Active Ingredient 4.50% Cyclopropene,1-methyl-|SMARTFRESH SMARTTABS Active Ingredient 0.63% Cyclopropene,1-methyl-|For more Formulations/Preparations (Complete) data for 1-METHYLCYCLOPROPENE (6 total), please visit the HSDB record page.

Use Sites: Ornamental plants; cut flowers; and harvested fruits and vegetables in enclosed indoor sites, such as coolers, truck trailers, greenhouses, storage facilities, and shipping containers. Application Methods: For use as a plant regulator active ingredient, 1-MCP is combined with other materials. When mixed with a specific amount of water or other appropriate solution, the 1-MCP gas is released to the air. Plants, flowers, fruits and vegetables must be treated for several hours in an enclosed space for the 1-MCP to be effective. 1-MCP is applied post harvest to fruits and vegetables. It is best used immediately after harvest in combination with chilling. It can be applied immediately after harvest, prior to storage, prior to shipment, or just prior to sale. It is applied in enclosed areas so the volatile active ingredient can be effective. Workers are not allowed into the treatment area until at least 30 minutes after the room has been vented.|The recent availability of the inhibitor of ethylene perception, 1-methylcyclopropene (1-MCP), has resulted in an explosion of research on its effects on fruits and vegetables, both as a tool to further investigate the role of ethylene in ripening and senescence, and as a commercial technology to improve maintenance of product quality. The commercialization of 1-MCP was followed by rapid adoption by many apple industries around the world, and strengths and weaknesses of the new technology have been identified. However, use of 1-MCP remains limited for other products ...

Agrochemicals -> Plant Growth Regulators|Plant growth regulators