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Chemical Datasheet

METHYLMERCURIC DICYANAMIDE

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 502-39-6
none data unavailable none
NIOSH Pocket Guide International Chem Safety Card
Mercury (organo) alkyl compounds (as Hg) none
NFPA 704
data unavailable
General Description
Crystals. Used as a fungicide; a seed, soil, and turf treatment, especially for cereals, sorghum, sugar beets, cotton, and flax. Not registered as a pesticide in the U.S. (EPA, 1998)

Hazards

Reactivity Alerts
none
Air & Water Reactions
No rapid reaction with air. No rapid reaction with water.
Fire Hazard
(Non-Specific -- Mercury-Based Pesticide, n.o.s.) This material may burn but does not ignite readily. Container may explode in heat of fire. Fire and runoff from fire control water may produce irritating or poisonous gases. When heated to decomposition, it emits very toxic fumes of mercury and nitrogen oxides. (EPA, 1998)
Health Hazard
Methylmercuric dicyanamide is extremely toxic to humans. The probable lethal dose for humans is 5-50 mg/kg of body weight (between 7 drops and one teaspoon for a 150 lb. person). Humans may be poisoned by feeding on the flesh of animals which have ingested this fungicide. Eating treated seeds may also cause poisoning. The poisoning may show delayed manifestations on the nervous system. Patients frequently become gradually worse after their illness is recognized and exposure is stopped. This compound is a strong skin irritant and produces blisters and other dermatitis. (EPA, 1998)
Reactivity Profile
METHYLMERCURIC DICYANAMIDE is incompatible with strong oxidizing agents such as chlorine (NIOSH, 2022).
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbent listed below.

Response Recommendations

Isolation and Evacuation
No information available.
Firefighting
(Non-Specific -- Mercury-Based Pesticide, n.o.s.) Fight fire from maximum distance. Dike fire control water for later disposal. Wear positive pressure breathing apparatus and special protective clothing.

(Non-Specific -- Mercury-Based Pesticide, n.o.s.) This material may burn but will 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)
Non-Fire Response
(Non-Specific -- Mercury-Based Pesticide n.o.s.) Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering. Remove and isolate contaminated clothing at the site. Do not touch spilled material. Use water to reduce vapors. In event of spill or leak: take up with absorbent material and place in containers with covers.

Small dry spill: with clean shovel place material into clean, dry container and cover; move containers from spill area. Dike far ahead of spill if large. (EPA, 1998)
Protective Clothing
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)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Warning: Signs and symptoms of methylmercuric dicyanamide exposure may occur at varying intervals up to several weeks. It is extremely toxic and also a strong skin irritant. Caution is advised.

Signs and Symptoms of Acute Methylmercuric Dicyanamide Exposure: Acute exposure to methylmercuric dicyanamide may include severe pulmonary and renal injury, hypotension (low blood pressure), respiratory distress, salivation, metallic taste, abdominal pain, nausea, vomiting, diarrhea and loss of feeling in lips and tongue. Exposure to the skin may produce blisters. Confusion, irritability, seizures, hallucinations, and loss of memory may also be noted. Mercury vapor may cause severe pulmonary damage and gingivitis if inhaled.

Emergency Life-Support Procedures: Acute exposure to methylmercuric dicyanamide 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 methylmercuric dicyanamide.
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. Rush to a health care facility.

Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self-exposure to methylmercuric dicyanamide.
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. Remove and isolate contaminated clothing and shoes as soon as possible. Speed in removing material from skin is of the extreme importance.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas thoroughly with water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Rush 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 methylmercuric dicyanamide 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 methylmercuric dicyanamide 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 ox); 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 the 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. Rush to a health care facility. (EPA, 1998)

Physical Properties

Chemical Formula:
  • C3H6HgN4
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 313°F (EPA, 1998)
Vapor Pressure: 6.5e-05 mmHg at 95°F (EPA, 1998)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: data unavailable
Molecular Weight: 298.72 (EPA, 1998)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: 2 mg Hg/m3 (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Methylmercuric dicyanamide (502-39-6) 0.045 mg/m3 0.06 mg/m3 3 mg/m3
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Mercury Compounds N458 & 313
Methylmercuric dicyanamide 502-39-6 500/10000 pounds 500 pounds 313c

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names