4-(2-メチル-4-クロロフェノキシ)酪酸

Store in original container separate from other pesticides, fertilizers, food and feed. /Technical MCPB/

Store in original container in a dry secured storage area. Keep container tightly closed when not in use. Protect from freezing. If allowed to freeze, hold in warm temperature for several days and remix before using. /Sodium MCPB/

Do not discharge effluent containing this product into lakes, streams, pond, estuaries, oceans or waters unless in accordance with the requirements of a National Pollutant Discharge Elimination System (NPDES) permit and the permitting authority has been notified in writing prior to discharge. Do not discharge effluent containing this product to sewer systems without previously notifying the local sewage treatment plant authority. ... Do not contaminate water, food or feed by storage, disposal, or cleaning of equipment. Open burning and dumping is prohibited. Do not re-use empty container. Wastes resulting from use of this product may be disposed of on site or at an appropriate waste disposal facility. ... Completely empty drum and triple rinse. Offer for recycling or reconditioning or dispose in a sanitary landfill or by other State and local procedures. /Technical MCPB/

Pesticide Disposal: Do not contaminate water, food or feed by storage or disposal. Wastes resulting from the use of this product may be disposed of on site or at an approved waste disposal facility. Container Disposal: Triple rinse (or equivalent). Then offer for recycling or reconditioning, or puncture and dispose of in a sanitary landfill, or incineration, or, if allowed by state and local authorities, by burning. If burned, stay out of smoke. /Sodium MCPB/

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.

If swallowed call a poison control center or doctor immediately for treatment advice. Have person sip a glass of water if able to swallow. Do not induce vomiting unless told to do so by a poison control center or doctor. Do not give anything by mouth to an unconscious person. If inhaled move person to fresh air. If person is not breathing, call 911 or an ambulance, then give artificial respiration ... if possible. Call a poison control center or doctor for further treatment advice. /Technical MCPB/

Wash thoroughly with soap and water after handling and before eating, drinking, chewing gom, or using tobacco. Remove and wash contaminated clothing before reuse. /Sodium MCPB/

Do not contaminate water, food, or feed by storage or disposal of this chemical.

Cleaning glassware and spray equipment: Thoroughly flush with detergents, dilute alkali, and water.

For more Preventive Measures (Complete) data for 2-METHYL-4-CHLOROPHENOXYBUTYRIC ACID (7 total), please visit the HSDB record page.

Wear protective eyewear (goggles, face shield, or safety glasses). Wear long-sleeved shirt and long pants, socks, shoes, and chemical resistant gloves (such as Natural Rubber)... When handlers use closed systems, enclosed cabs, or aircraft in a manner that meets the requirements listed in the Worker Protection Standard (WPS) for agricultural pesticides (40 CFR 170.240 (d) (4-6)), the handler PPE requirements may be reduced or modified as specified in the WPS. /Sodium MCPB/

Agricultural Use Requirements. Use this product only in accordance with its labeling and with the Worker Protection Standard (WPS), 40 CFR part 170. ... Do not enter or allow worker entry into treated areas during the restricted-entry interval (REI) of 12 hours. ... PPE required for early entry to treated areas that is permitted under the WPS and that involves contact with anything that has been treated, such as plants, soil, or water, is: coveralls, waterproof gloves, and shoes plus socks./Sodium MCPB/

LC50 Rainbow trout 4.3 mg ai/L/96 hrs; flow through. /Sodium MCPB/

LC50 Colinus virginianus (Northern bobwhite) oral >5000 ppm (No mortality at 2236 ppm, 10% at 5000 ppm), age 14 days

LC50 Phasianus colchicus (Ring-necked pheasant) oral >5000 ppm (No mortality to 5000 ppm), age 14 days

LC50 Anas platyrhynchos (Mallard duck) oral >5000 ppm (No mortality at 5000 ppm), age 10 days

For more Ecotoxicity Values (Complete) data for 2-METHYL-4-CHLOROPHENOXYBUTYRIC ACID (12 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc value of 780 from a log Kow of 2.79(2), and a regression derived equation(3),indicates that 2-methyl-4-chlorophenoxybutyric acid is expected to have low mobility in soil(SRC). 2-Methyl-4-chlorophenoxybutyric acid is a weak acid with pKa of 4.84(4), which indicates that it will exist primarily as an anion in moist soils and anions will not volatilize(SRC). 2-Methyl-4-chlorophenoxybutyric acid is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure of 4.3X10-7 mm Hg(2). Half-lives of less than 7 days were determined for 2-methyl-4-chlorophenoxybutyric acid at an initial concn of 2 ug/g in a clay loam, heavy clay, and a sandy loam kept at about 85 percent field capacity moisture and 20 °C(5).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 780(SRC) from a log Kow of 2.79(2), and a regression derived equation(3)indicates that 2-methyl-4-chlorophenoxybutyric acid is expected to adsorb to suspended solids and sediment(SRC). 2-Methyl-4-chlorophenoxybutyric acid is a weak acid with pKa of 4.84(2), which indicates that it will exist primarily as an anion in water surfaces and anions will not volatilize(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from its log Kow(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation half-lives of less than 7 days measured in soils(7), suggest that 2-methyl-4-chlorophenoxybutyric acid may also be susceptible to biodegradation in natural waters. Photolysis half-lives of 2-3 days were observed for 2-methyl-4-chlorophenoxybutyric acid in aqueous solutions exposed to sunlight(8), indicating photolysis in sunlit surface waters may be important(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-methyl-4-chlorophenoxybutyric acid which has a vapor pressure of 4.3X10-7 mm Hg at 25 °C(2), is expected to exist in both the vapor and particulate-phases in the ambient atmosphere(SRC). Vapor-phase 2-methyl-4-chlorophenoxybutyric acid 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 19 hours(SRC), calculated from its rate constant of 2.0X10-11 cu cm/molecule-sec at 25 °C(SRC), that was derived using a structure estimation method(3). Particulate-phase 2-methyl-4-chlorophenoxybutyric acid will be removed from the atmosphere by wet or dry deposition(SRC). 2-Methyl-4-chlorophenoxybutyric acid underwent photolysis in aqueous exposed to sunlight(4) suggesting that photolysis in air may be possible(SRC).

/AQUATIC SPECIES/ In a 96-hour flow-through test, MCPB sodium was determined to be moderately toxic to rainbow trout with an LC50 of 4.3 mg ai/L. The NOEC was determined to be 1.0 mg ai/L. ... Study design: Six concentrations of chemical and dilution water control were used, each with two replicates of ten fish. Observations for mortality and sublethal effects were made daily throughout the exposure period. Reported results: The mean measured concentrations of MCPB NA were: 0(control), 8.0, 4.9, 2.8, 1.8, 1.0, and 0.60 mg ai/L. Sublethal effects (eg. Loss of equilibrium and darkening) were observed in surviving fish at the 4.9, 2.8, and 1.8 mg ai/L; there were no other abnormal effects at any other test levels. There was 100% mortality at the 8.0 mg ai/L level within 48 hours, 70% mortality at 4.9 mg ai/L level by 96 hours, and 5% at 2.8 mg ai/L at 96 hours. /Sodium MCPB/

/AQUATIC SPECIES/In a 96-hour flow-through test, MCPB sodium was determined to be slightly toxic to bluegill sunfish with an LC50 of 14 mg ai/L. The NOEC was determined to be 8.9 mg ai/L. ... Study design: Six concentrations of chemical and dilution water control were used, each with two replicates of 10 fish. Observations for mortality and sublethal effects were made daily throughout the exposure period. Reported results: The mean measured concentrations of MCPB NA were: 0(control), 29, 16, 8.9, 56.4, 3.5 and 2 mg ai/L. Sublethal effects (eg. Loss of equilibrium and darkening) were observed in surviving fish at the 16 mg ai/L level; There were no other sublethal abnormal effects at any other test levels. There was 100% mortality at the 25 mg ai/L within 72 hours, and 75% mortality at the 16 mg ai /L level by 96 hours. There was a single mortality at the 3.5 mg ai/L level, but this was not considered treatment related as there were no mortalities at the next highest level (8.9 mg ai/L). /Sodium MCPB/

/AQUATIC SPECIES/ Aquatic Plant Algae: Blue-green algae...In a Tier I toxicity test with blue-green algae, the EC50 for cell density was >2.1 mg ai/L. Tier II testing was not required for this species because the NOEC exceeded the maximum label rate of 1.5 lb ai/acre...Green algae...In a Tier I toxicity test with green algae, the 120-hour EC50 for cell density was 0.42 mg ai/L. ...Marine diatom... In a Tier I and II toxicity test with the marine diatom, the 120-hour EC50 for cell density was 1.5 mg ai/L... Diatom... In a Tier I and II toxicity test with the diatom, the 120-hour EC50 for cell density was 0.71 mg ai/L with a 95% confidence limit of (0.11 - 4.6), The NOEC was .048mg ai/L.

/AQUATIC SPECIES/In a 48-hour flow-through test, MCPB sodium was determined to be slightly toxic to daphnids with an EC50 of 55 mg ai/L (95% confidence interval of 49 - 63 mg ai/L). The NOEC was determined to be 20 mg ai/L. ... Study design: Five concentrations of chemical and dilution water control were used, each with two replicates of 20 daphnids. Observations for mortality and sublethal effects were made daily throughout the exposure period. Reported results: The mean measured concentrations of MCPB NA were: 0 (control), 87, 51, 33, 20, and 12 mg ai/L. Sublethal effects (e.g. lethargy an carapace) were observed in all surviving daphnids at 87 and 51 mg ai/L, and in 15% of the daphnids at 33 mg ai/L. There was 95% mortality at the 87 mg ai/L and 45% mortality at 51 mg ai/L by the end of the test period.

4-(2-Methyl-4-chlorophenoxy) butyric acid (MCPB)

Hepatic

1 x 10 ^-2 mg/kg-day

The Koc of 2-methyl-4-chlorophenoxybutyric acid is estimated as 780(SRC), using a log Kow of 2.79(1)and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2-methyl-4-chlorophenoxybutyric acid is expected to have low mobility in soil.

/SIGNS AND SYMPTOMS/ Severe eye irritant. Harmful or fatal if swallowed. /MCPB Technical/

/SIGNS AND SYMPTOMS/ Corrosive. Causes irreversible eye damage. Harmful if swallowed or inhaled. Avoid contact with skin or clothing. /Sodium MCPB/

/SIGNS AND SYMPTOMS/ Not particularly irritating to skin ... . Causes pain and irritation on eyes and mucous membranes.

/EPIDEMIOLOGY STUDIES/ The possible role of agricultural chemicals in the etiology of biliary tract cancer was investigated in rice farming regions of Japan. Mortality data on biliary tract cancers were obtained from the vital statistics of the Ministry of Health and Welfare of Japan. An environmental pollution index ... was derived by dividing the total amount of agricultural chemicals used annually within each prefecture by the area of the prefecture. Prefectures polluted with either of the herbicides 4-chloro-2-methyl-phenoxyacetic acid or 4-(4-chloro-2-methylphenoxy)butyric acid had the highest biliary tract cancer mortality rates. This effect was observed in males with 4-chloro-2-methyl-phenoxyacetic acid and in both sexes with 4-(4-chloro-2-methylphenoxy)butyric acid. These compounds were also associated with cancers of the pancreas in males and of the stomach in both sexes. There was a strong correlation between environmental pollution indices of 4-chloro-2-methyl-phenoxyacetic acid and deaths from biliary tract cancer within 5 to 9 years.

For more Human Toxicity Excerpts (Complete) data for 2-METHYL-4-CHLOROPHENOXYBUTYRIC ACID (6 total), please visit the HSDB record page.

A tolerance is established for the herbicide 4-(2-methyl-4-chlorophenoxy) butyric acid in or on the following food commodity: [Table#3515]

The Agency has completed its review of submitted data and its assessment of the human and ecological risks associated with the use of pesticide products containing the active ingredient MCPB. Based on a review of these data, the Agency has sufficient information on the human health and ecological effects of MCPB to make decisions as part of the tolerance reassessment process under FFDCA and the reregistration process under FIFRA, as amended by FQPA. The Agency has determined that MCPB-containing products are eligible for reregistration provided that: (i) required product-specific data are submitted; (ii) the risk mitigation measures outlined in this document are adopted; and (iii) label amendments are made to reflect these measures.

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. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. 4-(2-methyl-4-chlorophenoxy)butyric acid is found on List B. Case No: 2365; Pesticide type: herbicide; Case Status: OPP is reviewing data from the pesticide's producers regarding its human health and/or environmental effects, or OPP is determining the pesticide's eligibility for reregistration and developing the Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): 4-(2-methyl-4-chlorophenoxy)butyric acid; Data Call-in (DCI) Date(s): 07/10/91; AI Status: The producers of the pesticide have made commitments to conduct the studies and pay the fees required for reregistration, and are meeting those commitments in a timely manner.