Continued on Page 2 

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FIELD FUMIGATION EMERGENCY RESPONDER GUIDE: 

CHLOROPICRIN 

THIS GUIDE IS FOR VAPOR EXPOSURES TO AIRBORNE EMISSIONS OF CHLOROPICRIN 

FOLLOWING SOIL INJECTION TO AGRICULTURAL FIELDS. CHLOROPICRIN MAY BE 

APPLIED ALONE OR IN COMBINATION WITH METHYL BROMIDE, 1,3-DICHLOROPROPENE, 

IODOMETHANE, OR DIMETHYL DISULFIDE. SEE FIELD POSTING FOR ACTUAL PRODUCT 

APPLIED. SEE EMERGENCY RESPONDER GUIDE FOR EACH CHEMICAL APPLIED. 

SEE PESTICIDE LABEL FOR EXPOSURE TO LIQUID OR SPILLS. 

POTENTIAL HAZARDS

HEALTH Chloropicrin behaves as a mild irritant at concentrations between 75 ppb 

and 150 ppb and is usually detected through odor and eye sensation, within 

5 minutes of exposure. At concentrations of about 75 ppb, eye sensation 

(prickliness or pinching) can be felt in about 20 minutes. Symptoms are 

temporary and reversible at concentrations up to 150 ppb. At levels above 

150 ppb headache, nausea and vomiting may occur. At levels above 580 

ppb for 8 hours or 2000 ppb for 10 minutes, life-threatening effects 

including pulmonary edema or death can occur 

The OSHA 8-hour TWA is 100 ppb. 

The NIOSH IDLH is 2000 ppb. 

Chloropicrin has been shown to not cause cancer in animal studies 

following long-term inhalation. Laboratory testing showed that at 

inhalation exposures below levels which produced permanent respiratory 

injury, birth defects or decrement in reproductive function did not occur. 

Chloropicrin is not expected to accumulate in human tissue. 

CHEMICAL 

PROPERTIES 

Chloropicrin is injected into the soil as a liquid where it becomes a vapor. 

Vapors are heavier than air, and will collect in low areas. Chloropicrin is 

volatile and concentrations may increase under still or low wind conditions. 

Vapors are not flammable or explosive. 

PUBLIC SAFETY 

FIRST AID Remove exposed persons to fresh air. Treat symptoms. Personal 

decontamination is not necessary for bystander exposure. 

CONTACT Contact certified applicator (24 hour telephone number is posted at the 

field). 

EVACUATION If the health symptoms of chloropicrin are present downwind of the 

application field, evacuate all bystanders and workers without respiratory 

protection in the downwind areas first. Evacuate a minimum of 1⁄4 mile or if 

the treated field is larger than 10 acres, evacuate 1⁄4 mile for every 10 acres 

of treated field. Evacuate upwind areas if winds are calm, variable or if 

atmospheric inversion conditions are present. If evacuation may increase 

exposures, Shelter In Place in all occupied structures until it is safe to 

evacuate. 

In general, Shelter in Place includes the following steps: 

1. Bring children and pets indoors immediately. If children are at 

school, do not try to bring them home unless told to. The school will shelter 
Page 2 of 2 

FIELD FUMIGATION EMERGENCY RESPONDER GUIDE: 

CHLOROPICRIN 

them. 

2. Turn off the heating, ventilation or air conditioning system. Turn off 

all fans, including bathroom fans operated by the light switch. 

3. Close the fireplace or woodstove damper 

4. If instructed to seal the room, use duct tape and plastic sheeting, 

such as heavy-duty plastic garbage bags, to seal all cracks around the door 

into the room. Tape plastic over any windows. Tape over any vents and seal 

electrical outlets and other openings. As much as possible, reduce the flow 

of air into the room. 

5. When told that the emergency is over, open windows and doors, turn 

on ventilation systems and go outside until the building's air has been 

exchanged with the now clean outdoor air. Follow any special instructions 

given by emergency authorities. 

These recommendations were excerpted from the American Red Cross and 

Centers For Disease Control and Prevention website for Shelter-in-Place 

During a Chemical or Radiation Emergency. The website address is: 

http://www.redcross.org/preparedness/cdc_english/Sheltering.asp#howdo.

DETECTION Use direct reading colorimetric detection devices such as Kitagawa Toxic 

Gas Detection Kit using tube No. 8014-172S, Drager kit using tube No. 

8103421, or Sensidyne Kit using tube No. 172S. Contact certified 

applicator for detection devices and tubes. 

PPE Wear loose fitting clothing. For concentrations above 150 ppb, a full face 

respirator fitted with organic vapor cartridges is required. For 

concentrations of 2,000 ppb or more, a self-contained breathing apparatus 

(SCBA) is required. 

MITIGATION 

FIELD Reduce emissions by applying water to all or part of the field via sprinklers, 

water truck, or flood irrigation. Potassium thiosulfate (KTS) may be added to 

water at concentrations up to 50% to increase effectiveness of water seal. 

STRUCTURES Ventilate all structures within evacuation area. Prior to allowing occupants 

to return to structures, no person should experience sensory irritation and 

air monitoring is required to confirm that chloropicrin concentrations are 

less than 150 ppb. 

Attention: The information set forth above is intended to be a summary of general information only. It is 

not intended to be a substitute for the emergency response and precautionary instructions provided on a 

government-approved product label or MSDS. It is the responsibility of persons intending to use this 

guide to read and follow the label and MSDS, and to comply with all applicable federal, state and local 

laws and regulations when responding to an emergency. 


0280.007 / 4 / 00073206.DOC 1

FIELD FUMIGATION EMERGENCY RESPONDER GUIDE: 

METAM SODIUM/METAM POTASSIUM AND MITC 

THIS GUIDE IS FOR VAPOR EXPOSURES TO AIRBORNE EMISSIONS OF METHYL 

ISOTHIOCYANATE (MITC) FOLLOWING APPLICATION OF METAM SODIUM OR METAM 

POTASSIUM TO AGRICULTURAL FIELDS. METAM SODIUM OR METAM POTASSIUM MAY 

BE APPLIED ALONE OR IN COMBINATION WITH 1,3-DICHLOROPROPENE OR 

CHLOROPICRIN. SEE FIELD POSTING FOR ACTUAL PRODUCT(S) APPLIED. SEE THE 

APPLICABLE EMERGENCY RESPONDER GUIDE FOR EACH CHEMICAL APPLIED. SEE 

PESTICIDE LABEL FOR EXPOSURE TO LIQUID OR SPILLS. 

POTENTIAL HAZARDS

HEALTH MITC, the conversion product of metam sodium and metam potassium 

application, behaves as a mild irritant at concentrations between 0.2 ppm 

and 0.8 ppm and is usually detected through eye sensation, within 5 

minutes of exposure. The odor threshold is 1.7 ppm. At levels above 0.8 

ppm, headache, nausea, and vomiting may occur. These symptoms are 

temporary and reversible following termination of exposure. 

US EPA AEGL (proposed and may be updated when final) 

 MITC AIR CONCENTRATION (ppm) 

Exposure Duration 

10 min 30 min 60 min 4 hr 8 hr 

AEGL-1 

(Notable discomfort) 0.8 0.8 0.8 0.8 0.8 

AEGL-2 (Disabling, 

irreversible damage) 43 29 23 9.0 4.3 

AEGL-3 

(Death) 130 88 70 27 13 

CHEMICAL 

PROPERTIES 

Metam sodium or metam potassium is injected into the soil in solution 

where it is converted into the vapor MITC. MITC is volatile and 

concentrations may increase under still or low wind conditions. MITC vapor 

is not flammable or explosive. 

PUBLIC SAFETY 

FIRST AID Remove exposed persons to fresh air. Treat symptoms. Personal 

decontamination is not necessary for bystanders with inhalation exposure. 

CONTACT Contact certified applicator (24-hour telephone number is posted at the 

field). 

EVACUATION If the health symptoms of MITC exposure are present downwind of the 

application field, evacuate all bystanders and all workers without 

respiratory protection in downwind areas first. Evacuate a minimum of 1⁄4 

mile, or if the treated field is larger than 10 acres, evacuate 1⁄4 mile for every 

10 acres of treated field. Evacuate adjacent areas around the field if winds 

are calm, variable, or if atmospheric inversion conditions are present. If 

evacuation may increase exposures, Shelter In Place all occupied structures 

until it is safe to evacuate. 

EPA has asked for specific instruction to accompany the “Shelter in Place” 

recommendation. In general, Shelter in Place includes the following steps: 

1. Bring children and pets indoors immediately. If children are at school, 

do not try to bring them home unless told to. The school will shelter 

them. 

2. Turn off the heating, ventilation or air conditioning system. Turn off all 

fans, including bathroom fans operated by the light switch. 

3. Close the fireplace or woodstove damper. 

4. If instructed to seal the room, use duct tape and plastic sheeting, such 
0280.007 / 4 / 00073206.DOC 2

as heavy-duty plastic garbage bags, to seal all cracks around the door 

into the room. Tape plastic over any windows. Tape over any vents and 

seal electrical outlets and other openings. As much as possible, reduce 

the flow of air into the room. 

5. When told that the emergency is over, open windows and doors, turn on 

ventilation systems and go outside until the building's air has been 

exchanged with the now clean outdoor air. Follow any special 

instructions given by emergency authorities. 

These recommendations were excerpted from the American Red Cross and 

Centers For Disease Control and Prevention website for Shelter-in-Place 

During a Chemical or Radiation Emergency. The website address is: 

http://www.redcross.org/preparedness/cdc_english/Sheltering.asp#howdo.

DETECTION Use direct reading colorimetric detection devices for MITC such as a Draeger 

kit using tube No. 8103485. Contact certified applicator for detection 

devices and tubes. 

PPE Wear loose fitting clothing. If odor is detected, face-sealing goggles and a 

respirator fitted with a pre-filter approved for pesticides and an organic 

vapor cartridge are required unless a full-face respirator with a pre-filter 

approved for pesticides organic vapor cartridges is worn. 

MITIGATION 

FIELD Reduce emissions by applying water to all or part of the field via sprinklers, 

water truck, flood irrigation, or other appropriate method. 

STRUCTURES Air monitoring is required to confirm that MITC concentrations are less than 

0.2 ppm, and no sensory irritation may be experienced for occupants to 

return to the structures. 

This document is intended as guidance to aid emergency responders. It should be considered 

as supplemental to information on the product label and MSDS and not as a replacement for 

that information.