methamidophos

H300: Fatal if swallowed [Danger Acute toxicity, oral]

H311: Toxic in contact with skin [Danger Acute toxicity, dermal]

H330: Fatal if inhaled [Danger Acute toxicity, inhalation]

H400: Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

P260, P262, P264, P270, P271, P273, P280, P284, P301+P316, P302+P352, P304+P340, P316, P320, P321, P330, P361+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

H300 (100%): Fatal if swallowed [Danger Acute toxicity, oral]

H310 (48.1%): Fatal in contact with skin [Danger Acute toxicity, dermal]

H311 (51.9%): Toxic in contact with skin [Danger Acute toxicity, dermal]

H330 (100%): Fatal if inhaled [Danger Acute toxicity, inhalation]

H400 (100%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

Aggregated GHS information provided per 79 reports by companies from 3 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

H310: Fatal in contact with skin [Danger Acute toxicity, dermal]

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

H371: May cause damage to organs [Warning Specific target organ toxicity, single exposure]

H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

P260, P262, P264, P264+P265, P270, P271, P280, P284, P301+P316, P302+P352, P304+P340, P305+P351+P338, P308+P316, P316, P319, P320, P321, P330, P337+P317, P361+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

Remove immediately from exposure. Fresh air, rest. Half-upright position. Refer immediately for medical attention.

Wear protective gloves when administering first aid. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer immediately for medical attention.

Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention.

Rinse mouth. Give a slurry of activated charcoal in water to drink, but NOT if convulsions occur. Rest. Refer immediately for medical attention.

Note: Methamidophos is a cholinesterase inhibitor.

Signs and Symptoms of Acute Methamidophos Exposure: Acute exposure to methamidophos may produce the following signs and symptoms: pinpoint pupils, blurred vision, headache, dizziness, muscle spasms, and profound weakness. Vomiting, diarrhea, abdominal pain, seizures, and coma may also occur. The heart rate may decrease following oral exposure or increase following dermal exposure. Chest pain may be noted. Hypotension (low blood pressure) may be noted, although hypertension (high blood pressure) is not uncommon. Respiratory symptoms include dyspnea (shortness of breath), respiratory depression, and respiratory paralysis. Psychosis may occur.

Emergency Life-Support Procedures: Acute exposure to methamidophos may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.

Inhalation Exposure:

1. Move victims to fresh air. Emergency personnel should avoid self-exposure to methamidophos.

2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.

3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

4. Transport to a health care facility.

Dermal/Eye Exposure:

1. Remove victims from exposure. Emergency personnel should avoid self- exposure to methamidophos.

3. Remove contaminated clothing as soon as possible.

4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.

5. Wash exposed skin areas three times with soap and water.

6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

7. Transport to a health care facility.

Ingestion Exposure:

1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.

2. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.

3. Vomiting may be induced with syrup of Ipecac. If elapsed time since ingestion of methamidophos is unknown or suspected to be greater than 30 minutes, do not induce vomiting and proceed to Step

4.Ipecac should not be administered to children under 6 months of age.Warning: Ingestion of methamidophos may result in sudden onset of seizures or loss of consciousness. Syrup of Ipecac should be administered only if victims are alert, have an active gag-reflex, and show no signs of impending seizure or coma. If ANY uncertainty exists, proceed to Step

4.The following dosages of Ipecac are recommended: children up to 1 year old, 10 mL (1/3 oz); children 1 to 12 years old, 15 mL (1/2 oz); adults, 30 mL (1 oz). Ambulate (walk) the victims and give large quantities of water. If vomiting has not occurred after 15 minutes, Ipecac may be readministered. Continue to ambulate and give water to the victims. If vomiting has not occurred within 15 minutes after second administration of Ipecac, administer activated charcoal.

4. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.

5. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.

6. Transport to a health care facility. (EPA, 1998)

(Non-Specific -- Organophosphorus Pesticide, n.o.s.) Stay upwind; keep out of low areas. Move containers from fire area if you can do it without risk. Fight fire from maximum distance. Dike fire control water for later disposal; do not scatter the material. Wear positive pressure breathing apparatus and special protective clothing.

(Non-Specific -- Organophosphorus Pesticide, n.o.s.) This material may burn, but does not ignite readily. For small fires, use dry chemical, carbon dioxide, water spray, or foam. For large fires, use water spray, fog, or foam. (EPA, 1998)

Use water spray, powder, alcohol-resistant foam, carbon dioxide.

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. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic/

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

Excerpt from ERG Guide 152 [Substances - Toxic (Combustible)]:

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 the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank 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, 2024)

Personal protection: complete protective clothing including self-contained breathing apparatus. Do NOT let this chemical enter the environment. Sweep spilled substance into covered sealable containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

Environmental considerations: Air spill: Apply water spray or mist to knock down vapors. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

Environmental considerations: Water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

Environmental considerations: 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. /Organophosphorus pesticides, liquid, flammable, toxic; Organophosphorus pesticides, liquid, toxic; Organophosphorus pesticides, solid, toxic/

Do NOT wash away into sewer. Sweep spilled substance into sealable containers; if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place. (Extra personal protection: complete protective clothing including self-contained breathing apparatus).

Hydrolysis... /of treated residues/: Alkaline hydrolysis produces methyl phosphoramidoate and methyl mercaptan. Those products are less hazardous. Acid hydrolysis yields... dimethylphosphorathioate and ammonia. ...Containers should be thoroughly drained and rinsed with aqueous alkali. Recommendable method: Incineration. Peer-review: Large amounts incinerate in a unit with effluent gas scrubbing. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

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.

DO NOT GET IN EYES, ON SKIN, OR CLOTHING, DO NOT BREATHE DUST, KEEP CONTAINER CLOSED. USE WITH ADEQUATE VENTILATION ... DO NOT DRINK ANY ALCOHOLIC BEVERAGES BEFORE OR DURING SPRAYING SINCE ALCOHOL PROMOTES ABSORPTION OF ORGANIC PHOSPHATES.

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. /Organophosphorus pesticides, solid, toxic

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. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. /Organophosphorus pesticides, liquid, toxic/

Personnel protection: Avoid breathing dusts, and fumes from burning material. 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. /Organophosphorus pesticides, solid, toxic/

For more Preventive Measures (Complete) data for METHAMIDOPHOS (10 total), please visit the HSDB record page.

(Non-Specific -- Organophosphorus Pesticide, n.o.s.) Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Do not touch spilled material; stop leak if you can do so without risk. Use water spray to reduce vapors.

Small spills: absorb with sand or other noncombustible absorbent material and place into containers for later disposal.

Small dry spills: with clean shovel place material into clean dry container and cover; move containers from spill area.

Large spills: dike far ahead of spill for later disposal. (EPA, 1998)

Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Dry. Keep in a well-ventilated room. Store in an area without drain or sewer access.

...Concentrates... should not be stored in mild steel containers.

...Keep container closed. ...

Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Dry. Keep in a well-ventilated room.

Biological Exposure Indices (BEI) [ACGIH] - Acetylcholinesterase activity in red blood cells = 70% of individual's baseline; Butylcholinesterase activity in serum or plasma = 60% of individual's baseline; Sample at end of shift; [TLVs and BEIs]

AEGL 1: Notable discomfort, irritation, or certain asymptomatic non-sensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure (Unit: mg/m3)

AEGL 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape (Unit: mg/m3)

AEGL 3: Life-threatening health effects or death (Unit: mg/m3)

2.4 mg/m3

4.5 mg/m3

10 mg/m3

1.9 mg/m3

3.6 mg/m3

8.1 mg/m3

1.2 mg/m3

2.3 mg/m3

5.1 mg/m3

0.61 mg/m3

1.1 mg/m3

2.5 mg/m3

NOTE THAT VALUES ARE IN mg/m3, NOT ppm.

AEGLs Status: Proposed

0.11 [mg/m3]

1.2 [mg/m3]

7.1 [mg/m3]

A harmful concentration of airborne particles can be reached quickly when dispersed, especially if powdered.

The substance is irritating to the eyes. The substance may cause effects on the nervous system by a cholinesterase inhibiting effect. This may result in convulsions, respiratory failure, heart failure and death. The effects may be delayed. Medical observation is indicated.

The substance may have effects on the nervous system. Cholinesterase inhibition. Cumulative effects are possible.

Tolerances are established for residues of the insecticide methamidophus (O,S-dimethyl phosphoramidothioate) in or on the following raw agricultural commodities: broccoli, 1.0 ppm; Brussels sprouts, 1.0 ppm; cabbage, 1.0 ppm; cauliflower, 1.0 ppm; cotton, undelinted seed, 0.1 ppm; cucumber, 1.0 ppm; eggplant, 1.0 ppm; lettuce, 1.0 ppm; melon, 0.5 ppm; pepper, 1.0 ppm; potatoe, 0.1 ppm; and tomato, 1.0 ppm.

Tolerances with regional registration, as defined in section 180.1(n), are established for residues of methamidophos in or on the following raw agricultural commodity: celery, 1 ppm.

For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)

... wear full protective equipment at all times. This includes: Neoprene-coated gloves, rubber workshoes or over-shoes, respirator or mask approved for toxic dust and organic vapors, overalls or rubber suit.

Chemical goggles, rubber gloves and impervious protective clothing.

NO open flames.

PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN! FIRST AID: USE PERSONAL PROTECTION. IN ALL CASES CONSULT A DOCTOR!

Use ventilation (not if powder), local exhaust or breathing protection.

Protective gloves. Protective clothing.

Wear face shield or eye protection in combination with breathing protection if powder.

Do not eat, drink, or smoke during work. Wash hands before eating.

Methamidophos is a crystalline solid, technical product is off-white with a pungent odor. Used as an insecticide on a number of vegetables and on cotton. (EPA, 1998)

Colorless crystals with a mercaptan-like odor; [HSDB] Colorless to white solid with a strong odor of mercaptans; Formulated as technical/manufacturing use liquid and emulsifiable concentrate end-use-product; [Reference #2]

COLOURLESS CRYSTALS.

Colorless crystals

Crystals from ether

Mercaptan-like odor

Decomposes (EPA, 1998)

Decomposes on heating without boiling

112 °F (EPA, 1998)

MP: 20-25 °C /Technical/

Melting point: 39-41 °C.

Soluble in aliphatic chlorinated hydrocarbons, alcohols; slightly soluble in ether.

Solubility (g/l) at 20 °C in: isopropanol: >200; dichloromethane: >200; hexane: 0.1-1; toluene: 2-5

Readily sol in n-hexane, dichloromethane, 2-propanol, toluene

Miscible in water

Solubility in water: good

1.31 at 112.1 °F (EPA, 1998) - Denser than water; will sink

1.27 g/cu cm at 20 °C

Relative density (water = 1): 1.3

1.31 @ 44.5°C

0.0003 mmHg at 86 °F (EPA, 1998)

0.000035 [mmHg]

4.7 mPa (3.5X10-5 mm Hg) at 25 °C

Vapor pressure, Pa at 20 °C: 0.002

0.0003 [mm Hg] @25 °C

log Kow = -0.8 @ 20 °C

STABLE AT AMBIENT TEMP... .

Stable at pH 3-8. Hydrolyzed in acids and alkalis.

When heated to decomposition it emits very toxic fumes of /nitrogen, phosphorous and sulfur oxides/.

...50% is decomposed in 140 hr at 40 °C and pH 2, in 120 hr at 37 °C and pH 9.

Slightly corrosive to mild steel and copper-containing alloys.

Positive

Agilent XCT

Electrospray ionization

formic acid (5.3nM)

MeCN (80%)

DOI:10.1038/s41598-020-62573-z

Index of refraction: 1.5092 @ 40 °C/D

123.4 Ų [M+H]+ [CCS Type: DT; Buffer gas: N2; Ionization: ESI+; Dataset: Pesticides]

123.2 Ų [M+H]+ [CCS Type: DT; Method: single field calibrated]

No rapid reaction with air. No rapid reaction with water.

Esters, Sulfate Esters, Phosphate Esters, Thiophosphate Esters, and Borate Esters

Acids, Weak

Organophosphates, such as METHAMIDOPHOS, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides. Avoid strong acids or alkalis. [EPA, 1998].

Attacks mild steel and copper-containing alloys (technical grade).

... Incompatible with alkaline materials.

(±)-Methamidophos is a cholinesterase or acetylcholinesterase (AChE) inhibitor. A cholinesterase inhibitor (or 'anticholinesterase') suppresses the action of acetylcholinesterase. Because of its essential function, chemicals that interfere with the action of acetylcholinesterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses, followed by muscle spasms and ultimately death. Nerve gases and many substances used in insecticides have been shown to act by binding a serine in the active site of acetylcholine esterase, inhibiting the enzyme completely. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop. Among the most common acetylcholinesterase inhibitors are phosphorus-based compounds, which are designed to bind to the active site of the enzyme. The structural requirements are a phosphorus atom bearing two lipophilic groups, a leaving group (such as a halide or thiocyanate), and a terminal oxygen.

Methamidophos

5 x 10 ^-5 mg/kg-day

Pesticide

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

Cancer Classification: Not Likely to be Carcinogenic to Humans

No indication of carcinogenicity to humans (not listed by IARC).

Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Certain reproductive effects in fertility, growth, and development for males and females have been linked specifically to organophosphate pesticide exposure. Most of the research on reproductive effects has been conducted on farmers working with pesticides and insecticdes in rural areas. In females menstrual cycle disturbances, longer pregnancies, spontaneous abortions, stillbirths, and some developmental effects in offspring have been linked to organophosphate pesticide exposure. Prenatal exposure has been linked to impaired fetal growth and development. Neurotoxic effects have also been linked to poisoning with OP pesticides causing four neurotoxic effects in humans: cholinergic syndrome, intermediate syndrome, organophosphate-induced delayed polyneuropathy (OPIDP), and chronic organophosphate-induced neuropsychiatric disorder (COPIND). These syndromes result after acute and chronic exposure to OP pesticides.

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

Dizziness. Pupillary constriction, muscle cramp, excessive salivation. Sweating. Laboured breathing. Weakness. Abdominal cramps. Diarrhoea. Nausea. Vomiting. Muscle twitching. Convulsions. Unconsciousness.

MAY BE ABSORBED! Further see Inhalation.

Redness. Pain. Blurred vision.

See Inhalation.

Symptoms of low dose exposure include excessive salivation and eye-watering. Acute dose symptoms include severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Hypertension, hypoglycemia, anxiety, headache, tremor and ataxia may also result.

Neurotoxin - Predominantly motor

Other Poison - Organophosphate

FAO/WHO ADI: 0.004 mg/kg

Oral RfD: 0.00005 mg/kg/day (UF: 1000, MF: 1)

IRIS Current

Children

General Population

Human Health Benchmarks for Pesticides - 2021 Update

LC50 (rat) = 162 mg/m3/4hr

LD50 Rat male dermal 94 mg/kg

LD50 Rat female dermal 85 mg/kg

LD50 Rabbit oral 10 mg/kg

LD50 Rat percutaneous 50-110 mg/kg

For more Non-Human Toxicity Values (Complete) data for METHAMIDOPHOS (13 total), please visit the HSDB record page.

If the compound has been ingested, rapid gastric lavage should be performed using 5% sodium bicarbonate. For skin contact, the skin should be washed with soap and water. If the compound has entered the eyes, they should be washed with large quantities of isotonic saline or water. In serious cases, atropine and/or pralidoxime should be administered. Anti-cholinergic drugs work to counteract the effects of excess acetylcholine and reactivate AChE. Atropine can be used as an antidote in conjunction with pralidoxime or other pyridinium oximes (such as trimedoxime or obidoxime), though the use of '-oximes' has been found to be of no benefit, or possibly harmful, in at least two meta-analyses. Atropine is a muscarinic antagonist, and thus blocks the action of acetylcholine peripherally.

Because different classes of enzymes may be inhibited, the effects of organophosphorus pesticide poisoning may be complex and potentially at least could involve interactions with drugs as well as with other pesticides or chemicals. Potentiation may also involve solvents or other components of formulated pesticides. Certain drugs such as phenothiazines, antihistamines, CNS depressants, barbiturates, xanthines (theophylline), aminoglycosides and parasympathomimetic agents are to be avoided because of increased toxicity. /Organophosphorus pesticides/

Airway protection. Ensure that a clear airway exists. Intubate the patients and aspirate the secretions with a large-bore suction device if necessary. Administer oxygen by mechanically assisted pulmonary ventilation if respiration is depressed. Improve tissue oxygenation as much as possible before administering atropine, so as to minimize the risk of ventricular fibrillation. In severe poisonings, it may be necessary to support pulmonary ventilation mechanically for several days. /Organophosphate pesticides/

Atropine sulfate. Administer atropine sulfate intravenously, or intramuscularly if intravenous injection is not possible. ...The objective of atropine antidotal therapy is to antagonize the effects of excessive concentrations of acetylcholine at end-organs having muscarinic receptors. Atropine does not reactivate the cholinesterase enzyme or accelerate disposition of organophosphate. Recrudescence of poisoning may occur if tissue concentrations of organophosphate remain high when the effect of atropine wears off. Atropine is effective against muscarinic manifestations, but it is ineffective against nicotinic actions, specifically muscle weakness and twitching, and respiratory depression. ...However, lack of response, with no evidence of atropinization (atropine refractoriness) is typical of more severe poisonings. The adjunctive use of nebulized atropine has been reported to improve respiratory distress, decrease bronchial secretions, and increase oxygenation. ...Do not administer atropine or pralidoxime prophylactically to workers exposed to organophosphate pesticides. Prophylactic dosage with either atropine or pralidoxime may mask early signs and symptoms of organophosphate poisoning and thus allow the worker to continue exposure and possibly progress to more severe poisoning. Atropine itself may enhance the health hazards of the agricultural work setting: impaired heat loss due to reduced sweating and impaired ability to operate mechanical equipment due to blurred vision. This can be caused by mydriasis, one of the effects of atropine. /Organophosphate pesticides/

Glycopyrolate has been studied as an alternative to atropine and found to have similar outcomes using continuous infusion. Ampules of ...glycopyrolate were added to ...saline and this infusion was titrated to the desired effects of dry mucous membranes and heart rate above 60 beats/min. During this study, atropine was used as a bolus for a heart rate less than 60 beats/min. The other apparent advantage to this regimen was a decreased number of respiratory infections. .../Organophosphate pesticides/

Pralidoxime. Before administration of pralidoxime, draw a blood sample (heparinized) for cholinesterase analysis (since pralidoxime tends to reverse the cholinesterase depression). Administer pralidoxime (Protopam, 2-PAM), a cholinesterase reactivator, in cases of severe poisoning by organophosphate pesticides in which respiratory depression, muscle weakness, and/or twitching are severe. When administered early (usually less than 48 hours after poisoning) pralidoxime relieves the nicotinic as well as the muscarinic effects of poisoning. Pralidoxime works by reactivating the cholinesterase and also by slowing the "aging" process of phosphorylated cholinesterase to a non-reactivatable form. ... Dosage of pralidoxime may be repeated in 1-2 hours, then at 10-12 hour intervals if needed. In very severe poisonings, dosage rates may be doubled. Repeated doses of pralidoxime are usually required. In cases that involve continuing absorption of organophosphate (as after ingestion of large amounts), or continuing transfer of highly lipophilic organophosphate from fat into blood, it may be necessary to continue administration of pralidoxime for several days beyond the 48 hour post-exposure interval usually cited as the limit of its effectiveness. ... Blood pressure should be monitored during administration because of the occasional occurrence of hypertensive crisis. Administration should be slowed or stopped if blood pressure rises to hazardous levels. Be prepared to assist pulmonary ventilation mechanically if respiration is depressed during or after pralidoxime administration. If intravenous injection is not possible, pralidoxime may be given by deep intramuscular injection. /Organophosphate pesticides/

For more Antidote and Emergency Treatment (Complete) data for METHAMIDOPHOS (17 total), please visit the HSDB record page.

Measurement of whole blood-AChE is the most widely adopted method for monitoring the effects of occupational exposure to organophosphorus insecticides. Physiological variations in blood ChE levels occur in a healthy person and are seen among a population. It has been estimated that the coefficient of variation for AChE activity in samples from an individual is 8-11%, and that a decrease of 23% below pre-exposure level may, therefore, be considered significant. If the average of several pre-exposure values were available, then a decrease of 17% would be significant. It has been recommended that, if measured activity is reduced by 30% or more of the pre-exposure value, AChE measurements should be repeated at appropriate intervals to confirm the results. Depressions of AChE or ChE in excess of 20-25% are considered diagnostic of exposure but not, necessarily, indicative of hazard. Depressions of 30-50% or more are considered indicators for removal of an exposed individual from further contact with pesticides until levels return to normal. /Organophosphorus Pesticides/

...Organophosphorus pesticides may undergo hydrolysis in vivo to yield substituted phosphoric acids that are subsequently excreted in urine. Advances in gas chromatography and combined gas chromatography/mass spectrometry (GC/MS) have made it possible to analyse the urine of exposed persons for the presence of appropriate metabolites. It is usually necessary to preserve the sample by the addition of chloroform, to concentrate or extract the metabolite(s), and to convert them to suitably-volatile derivatives that can be detected by GC. Obviously, access to a well-equipped analytical laboratory, capable of the quick processing of samples, is a necessary factor if monitoring by urine analysis is proposed. However, in some cases, simpler and sensitive colorimetric tests are available for screening the urine of exposed persons. Thus, 4-nitrophenol can be measured directly in the urine of workers exposed to parathion. Consideration of the concentration of metabolite(s) in the urine can be helpful in determining patterns of exposure, and these concentrations can be calibrated against the effects on AChE for a particular pesticide. However, the time-course and peak of excretion of metabolites appears to vary according to dose, so that serial sampling and analyses of urine are desirable. Levels of metabolite alone cannot be considered a guide to hazard. This is obvious when it is realized that pesticides that have very different toxicities may yield identical acidic metabolites. Thus, the level of metabolites in urine, after exposure to sufficient amounts of the very toxic parathion-methyl to depress blood-AChE to 50%, will be much lower than that of the identical metabolites, following exposure to the related fenitrothion, which is about 40 times less toxic. /Organophosphorus Pesticides/

SRP: Workers should undergo an annual medical exam. Contraindications for work with organophosporous pesticides are organic diseases of the CNS, mental disorders and epilepsy, and pronounced endocrine disorders. Blood cholinesterase, both plasma and RBC, must be determined before work starts. In the event of prolonged work periods, this activity should be determined at intervals of 3-4 days. Persons exhibiting a fall in cholinesterase activity of 25% or more must be transferred to other work where they are not exposed until cholinesterase activity is restored. /Organophosphorous pesticides/

/HUMAN EXPOSURE STUDIES/ Delayed neuropathies in occupationally exposed workers have been reported for only a few of the many currently used organophosphorus insecticides. For one pesticide, methamidophos, the syndrome has not been reproduced in experimental animals. There is no specific treatment for neuropathy, though physiotherapy may limit the degree of muscle wasting that follows denervation. In mild cases, some slow improvement can occur, but, in more severe cases, the defects are permanent.

/HUMAN EXPOSURE STUDIES/ Signs and symptoms of acute intoxication by organophosphorus insecticides include muscarinic, nicotinic, and central nervous system (CNS) manifestations. Symptoms may develop rapidly, or there may be a delay of several hours after exposure before they become evident. The delay tends to be longer in the case of more lipophilic compounds, which also require metabolic activation. Symptoms may increase in severity for more than one day and may last for several days. In severe cases, respiratory failure is a dominant effect.

LC50 Rainbow trout 25 ppm/96 hr, static

LC50 Bluegill sunfish 34 ppm/96 hr, static

LC50 Penaeus stylirostris naupliae (Shrimp larvae) 160 ng/l/12 hr; 10 ng/l/24 hr; 0.6 ng/l/36 hr /Conditions of bioassay not specified/

LC50 Penaeus stylirostris (Shrimp larvae) 300 ng/l/12 hr; 85 ng/l/24 hr; 2.4 ng/l/36 hr /Conditions of bioassay not specified/

For more Ecotoxicity Values (Complete) data for METHAMIDOPHOS (16 total), please visit the HSDB record page.

/BIRDS and MAMMALS/ The effects in avian reproduction testing included reduced egg thickness. In Northern bobwhite quail the NOEC for reproductive effects was 3 ppm and the LOEC was 5 ppm based on egg thickness. In a study with the Mallard duck, the NOEC was >15 ppm and the LOEC was also >15 ppm (no effect). /from table/

/AQUATIC SPECIES/ Groups of 200 larvae were ...exposed to 0, 0.01, and 0.10 ng/l Monitor in aerated glass carboys for 33 days. Experiments were conducted at salinities of 15 g/l for larvae and 2 g/l for early postlarvae, in algae free water (clearwater) as well as phytoplankton rich water (greenwater) Increasing concn of Monitor reduced survival and slowed development. In clearwater, concn of 0.01 and 0.10 ng/l Monitor decr survival by 13 and 15% respectively, and postlarvae production by 35 and 48%, when compared with clearwater controls. In greenwater, concn of 0.01 and 0.10 ng/l also decr survival by 24 and 16%. After 33 days, greenwater reared larvae showed an avg of 5.6% higher survival and 46.3% higher production of postlarvae than clearwater reared larvae.

/OTHER TERRESTRIAL SPECIES/ Product is harmful to bees.

/PLANTS/ No phytotoxicity observed at effective rates when applied to vegetable or field crops but defoliation has occurred when applied as foliar spray to deciduous fruit.

/FIELD STUDIES/ Die-offs of sage grouse (Centrocercus urophasianus) were verified in southeastern Idaho in 1981. Eighty-two apparently healthy grouse were captured to quantify the effects of organophosphorus insecticides and other pesticides on sage grouse in sagebrush (Artemisia species) bordering agricultural lands in July 1985 and 1986. Grouse were fitted with radio collars and tracked through part of each summer. At least 18% of 82 radio-tagged grouse in 1985-86 subsequently occupied fields at the time they were sprayed with organophosphorus insecticide methamidophos. Cholinesterase assays of brains and residue analysis of crop contents indicated that 5 and 16% of the marked sample died from organophosphorus insecticides in 1985 and 1986, respectively. Maximum residues in crop contents of dead grouse were 18 ug/g methamidophos. Intoxicated or dead grouse were observed in or near 6 fields sprayed with methamidophos in 1985-86.

3.20e+00

4.10e+01

1.00e+00

2.00e+00

2.10e-04

Volatile

9.50e+00

1.20e+02

3.00e+00

The substance is very toxic to aquatic organisms. This substance may be hazardous to the environment. Special attention should be given to birds and bees. This substance does enter the environment under normal use. Great care, however, should be taken to avoid any additional release, for example through inappropriate disposal.

Methamidophos' production may result in its release to the environment through various waste streams; its use as an insecticide and acaricide will result in its direct release to the environment. If released to air, a vapor pressure of 3.5X10-5 mm Hg at 25 °C indicates methamidophos will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase methamidophos will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 12 hours. Particulate-phase methamidophos will be removed from the atmosphere by wet and dry deposition. If released to soil, methamidophos is expected to have very high mobility based upon a Koc of 5. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 8.7X10-10 atm-cu m/mole. Volatilization from dry soil surfaces is not expected, base on methamidophos' vapor pressure. Average half-lives in soil under aerobic and anaerobic conditions are 4 and 7.5 days, respectively. If released into water, methamidophos is not expected to adsorb to suspended solids and sediment based upon the Koc. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 3.1 suggests the potential for bioconcentration in aquatic organisms is low. Half-lives for the hydrolysis of methamidiophos at 22 °C and pH 4, 7, and 9 have been reported to be 1.8 years, 120 hours, and 70 hours, respectively. Photolysis rates in water and soil are 0.0079 and 0.210 per day; corresponding to half-lives of 87 and 3.3 days, respectively. Occupational exposure to methamidophos may occur through inhalation and dermal contact with this compound at workplaces where methamidophos is produced or used. Monitoring data indicate that the general population may be exposed to methamidophos via ingestion of food. (SRC)

Methamidophos' production may result in its release to the environment through various waste streams; its use as an insecticide and acaricide(1) will result in its direct release to the environment(SRC).

ORTHENE WAS INTRODUCED INTO A NATURAL STREAM, AND DEGRADATION, INSECTICIDAL AND PISCICIDAL ACTIVITIES, AND CONVERSION OF ORTHENE TO MONITOR WAS FOLLOWED. NO ORTHENE WAS DETECTED 4 DAYS FOLLOWING ITS INTRODUCTION INTO WATER. TRACES OF MONITOR, A METABOLITE OF ORTHENE, WERE FOUND IN THE SEDIMENT. FISH CONVERTED ORTHENE TO MONITOR; HOWEVER, BY 1 DAY POST-APPLICATION ORTHENE AND MONITOR WERE CLEARED FROM THE TISSUES. CONVERSION OF ORTHENE TO MONITOR WAS ALSO FOUND IN THE INSECTS. AT 8 HR POST APPLICATION, INSECTS WERE CLEAR OF ORTHENE AND MONITOR.

Terrestrial Fate: The behavior of (32)P methamidophos was tested in six soils with significant differences in texture, clay composition, and pH. The amt of methamidophos bound in test soils increased with the content of illite in the clay fraction in the order sand < loamy sand < silt loam. Metabolic degradation takes place in sandy soils on an extremely small scale, is higher in loamy sands and reaches the highest rate in silt loam. This trend is related to the microbial activity of the soils. In bog soils, hydrolysis is the major process in degradation.

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc value of 5(2), indicates that methamidophos is expected to have very high mobility in soil(SRC). Volatilization of methamidophos from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 8.7X10-10 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Methamidophos is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.5X10-5 mm Hg(4). Average half-lives in soil under aerobic and anaerobic conditions are 4 and 7.5 days, respectively(5). The photolysis rate in soil is reported as 0.210 per day(5), corresponding to a half-life of 3.3 days(SRC).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 5(2), indicates that methamidophos is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 8.7X10-10 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). According to a classification scheme(5), an estimated BCF of 3.1(SRC), from its log Kow of -0.8(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Half-lives for the hydrolysis of methamidiophos at 22 °C and pH 4, 7, and 9 have been reported to be 1.8 years, 120 hours, and 70 hours, respectively(6). The photolysis rate in water is 0.0079 per day(8), corresponding to a half-life of 87 days(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methamidophos, which has a vapor pressure of 3.5X10-5 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase methamidophos 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 12 hours(SRC), calculated from its rate constant of 2.8X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase methamidophos may be removed from the air by wet and dry deposition(SRC).

AEROBIC: Half-lives in Mooretown, NJ loam, Florida sandy loam, and sandy loam were 0.583, 4.8, and 6.1 days under aerobic conditions(1).

ANAEROBIC: Half-lives in loamy sand and sandy loam were 11 and 4 days, respectively, under anaerobic conditions(1).

The rate constant for the vapor-phase reaction of methamidophos with photochemically-produced hydroxyl radicals has been estimated as 2.8X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 12 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Half-lives for the hydrolysis of methamidiophos at 22 °C and pH 4, 7, and 9 have been reported to be 1.8 years, 120 hours, and 70 hours, respectively(2). Photolysis rates in water and soil are 0.0079 and 0.210 per day(3); corresponding to half-lives of 87 and 3.3 days, respectively(SRC).

An estimated BCF of 3.1 was calculated for methamidophos(SRC), using a log Kow of -0.8(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).

A Koc of 5 has been reported for methamidophos(1). According to a classification scheme(2), this Koc value suggests that methamidophos is expected to have very high mobility in soil.

The Henry's Law constant for methamidophos is estimated as 8.7X10-10 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that methamidophos is expected to be essentially nonvolatile from water surfaces(2). Methamidophos' Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Methamidophos is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure of 3.5X10-5 mm Hg(3).

GROUNDWATER: Methamidophos was found in the range of 0.09 to 10.5 ppb in 9 out of 38 wells in Maine sampled for groundwater(1).

GROUNDWATER: According to the U.S. Environmental Protection Agency Office of Pesticide Programs Pesticides in Groundwater Database, which complied monitoring studies for 1971-1991, methamidophos was not detected in 779 wells sampled from California (1984-1989), and was detected in 4 of 35 wells in Maine (1986-1987) at concentrations ranging from trace to 10 ug/l(1).

SURFACE WATER: Methamidophos was found at concentrations ranging from <0.1 to 0.9 ug/l in some of the Andean Highland watercourses, from the Merida Province of Venezuela in 1990(1). These watercourses serve as drainage for a region of farms that cultivate crops such as potatoes, cabbage, and carrots(1). Mean concentrations of methamidophos from 22 sites collected during 1989-1990 from the Guadalquivir River Basin in Spain ranged from 0 to 0.11 ug/l(2).

SEDIMENT: Methamidophos concentrations in sediment collected during 1988-1989 from three sites from the Sarno River, southern Italy were 117, 130, and 200 ng/g dry weight(1). Methamidophos concentrations in sediment from the Volturno River, southern Italy were below the detection limit (<30 pg/g dry weight) for two sites and 130 ng/g dry weight for a third site(1).

Methamidophos was qualitatively identified as residues in food samples tested during the Food and Drug Administration pesticide residue monitoring of various food samples for the test periods of 1978-1982 and 1983-1986(1-2). Methamidophos was qualitatively identified in 1.144% and 0.947% of all food samples tested during the Food and Drug Administration pesticide residue monitoring of various food samples for the test periods of 1988 and 1989, respectively(3). Methamidophos was qualitatively identified in 5% of 1170 food samples tested during the Food and Drug Administration pesticide residue monitoring of various food samples for the test period of 1988(4). Methamidophos was identified at concentrations ranging from 0.05 to 2.0 ppm in 24% of all food and animal feeds tested during the Food and Drug Administration's Los Angeles District Laboratory pesticide residue monitoring of various foods and animal feeds for the test period of 1982-1986(5).

Methamidophos was qualitatively identified in 100%, 13%, 8%, 7%, 33%, 5%, and 53% of beans, broccoli, cabbage, cauliflower, lettuce, potato, and tomato samples tested during the California Department of Food and Agriculture pesticide residue monitoring of various food samples for the test period of 1989, respectively(1).

In the U.S. FDA regulatory monitoring of domestic foods which may be eaten by infants/children (1985-1991), methamidophos was found in the following foods (number of findings, max concentration ppm): apples (2, trace) and oranges (2, 0.17)(1). In the U.S. FDA regulatory monitoring of imported foods which may be eaten by infants/children (1985-1991), methamidophos was found in the following foods (number of findings, max concentration ppm): apple juice (1, trace), apples (1, 0.02), grape juice (1, trace), and pears (7, 0.02)(1). In the Total Diet Study (1985-1991) of infant foods, methamidophos residues were found in the following foods (number of findings, max concentration ppm): oatmeal with applesauce and bananas (1, 0.001), tomatoes, beef, and macaroni (2, 0.001), vegetable with beef (1, 0.002), green beans (21, 0.018), and mixed vegetables (3, 0.001)(1). Methamidophos residues found in the selected Total Diet Study (1985-1991) of adult foods eaten by infants/children were (number of findings, max concentration ppm) in canned apple juice (2, 0.0008), raw apples with the peel (1, 0.0009), and raw pear (1, 0.0007)(1). In an U.S. FDA study (1982-1991), which included 37 market basket studies, each containing 234 food items representing about 5000 food types in American diets covering all age groups, methamidophos was detected 427 times in 49 foods with an average concentrations of 0.0111 ug/g(2). In 1992-1993, the U.S. FDA studied the pesticide residues in domestic and imported pears and tomatoes; methamidophos was detected in 56 and 66% of domestic and imported tomatoes at maximum concentrations of 0.68 and 0.30 ppm, respectively and was not detected in pears(3). Detection of methamidophos was found to occur with a frequency of 3, 5, 6 and 5% in the U.S. FDA Total Diet Study 1982-1984, 1984-1986, 1986-1991 and 1994, respectively(4-6).

Do NOT wash away into sewer. Sweep spilled substance into sealable containers; if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place. (Extra personal protection: complete protective clothing including self-contained breathing apparatus).

Hydrolysis... /of treated residues/: Alkaline hydrolysis produces methyl phosphoramidoate and methyl mercaptan. Those products are less hazardous. Acid hydrolysis yields... dimethylphosphorathioate and ammonia. ...Containers should be thoroughly drained and rinsed with aqueous alkali. Recommendable method: Incineration. Peer-review: Large amounts incinerate in a unit with effluent gas scrubbing. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

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.

/GUIDE 131: FLAMMABLE LIQUIDS-TOXIC/ Health: TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Inhalation or contact with some of these materials will irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. /Organophosphorus pesticide, liquid, flammable, poisonous; Organophosphorus pesticide, liquid, flammable, toxic; Organophosphorus pesticide, liquid, poisonous, flammable; Organophosphorus pesticide, liquid, toxic, flammable/

/GUIDE 131: FLAMMABLE LIQUIDS-TOXIC/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion and poison hazard indoors, outdoors or in sewers. Those substances designated with a "P" may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. /Organophosphorus pesticide, liquid, flammable, poisonous; Organophosphorus pesticide, liquid, flammable, toxic; Organophosphorus pesticide, liquid, poisonous, flammable; Organophosphorus pesticide, liquid, toxic, flammable/

/GUIDE 131: FLAMMABLE LIQUIDS-TOXIC/ Public Safety: CALL Emergency Response Telephone Number ... . As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering. /Organophosphorus pesticide, liquid, flammable, poisonous; Organophosphorus pesticide, liquid, flammable, toxic; Organophosphorus pesticide, liquid, poisonous, flammable; Organophosphorus pesticide, liquid, toxic, flammable/

/GUIDE 131: FLAMMABLE LIQUIDS-TOXIC/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. /Organophosphorus pesticide, liquid, flammable, poisonous; Organophosphorus pesticide, liquid, flammable, toxic; Organophosphorus pesticide, liquid, poisonous, flammable; Organophosphorus pesticide, liquid, toxic, flammable/

For more DOT Emergency Guidelines (Complete) data for METHAMIDOPHOS (16 total), please visit the HSDB record page.

UN 2783; Organophosphorus pesticides, solid, toxic, NOS

UN 3018; Organophosphorus pesticides, liquid, toxic, NOS

UN 2784; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint 23 °C or more

UN 3017; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint less than 23 °C

IMO 6.1; Organophosphorus pesticides, solid, toxic, NOS; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint 23 °C or more; Organophosphorus pesticides, liquid, toxic, flammable, NOS, flashpoint less than 23 °C; Organophosphorus pesticides, liquid, toxic, NOS

49 216 74; Organophosphorus pesticide, liquid, not otherwise specified (compounds and preparations) (insecticides, other than agricultural, NEC)

49 216 75; Organophosphorus pesticide, liquid, not otherwise specified (compounds and preparations) (agricultural insecticides, NEC, liquid)

49 105 44; Organophosphorus pesticide, liquid, not otherwise specified (compounds and preparations) (insecticides, other than agricultural, NEC)

49 105 45; Organophosphorus pesticide, liquid, not otherwise specified (compounds and preparations) (agricultural insecticides, NEC, liquid)

49 216 76; Organophosphorus pesticide, solid, not otherwise specified (compounds and preparations) (insecticides, other than agricultural, NEC)

49 216 77; Organophosphorus pesticide, solid, not otherwise specified (compounds and preparations) (agricultural insecticides, NEC, other than liquid)

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Marine pollutant

Unbreakable packaging. Put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs. Marine pollutant.

Symbol: T+, N; R: 24-26/28-50; S: (1/2)-28-36/37-45-61

UN Hazard Class: 6.1; UN Pack Group: II