UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

MEMORANDUM 

Date: May 8, 2013 

SUBJECT: Aluminum Phosphide, Magnesium Phosphide and Phosphine: 

Review of Human Incidents 

PCCode:066501,066504, 066500 

Decision No.: 476795 

Petition No.: NA 

DP Barcode: 0411384 

Registration No.: NA 

Regulatory Action: NA 

Risk Assessment Type: NA Case No.: NA 

TXRNo.: NA 

MRIDNo.:NA 

CAS No.: 20859-73-8, 12057-74-8,7803-51-2 

40 CFR: NA 

FROM: Shanna Recore, Industrial Hygienist . II (}. /1. 11 Toxicology and Epidemiology Branch \}LJI\...YU/; 

Health Effects Division (7509P) 

and 

Elizabeth Evans, Environmental Protection Specialist 

Toxicology and Epidemiology Branch 

Health Effects Division (7509P) 

THROUGH: David J. Miller, Acting Branch Chief a) J!l/£.. 

Toxicology and Epidemiology Branch 

Health Effects Division (7509P) 

TO: Thurston Morton, Risk Assessor 

Risk Assessment Branch IV 

Health Effects Division (7509P) 

and 

Dana Friedman, Chemical Review Manager 

Risk Management & Implementation Branch 2 

Pesticide Re-evaluation Division (7508P) 

Summary and Conclusions 

Yer.Apr.08 

For magnesium phosphide and phosphine there is relatively low frequency and severity of 

incident cases reported both IDS and NIOSH SENSOR-Pesticides, there does not appear to be a 

concern at this time that would warrant further investigation. The Agency will continue to 

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monitor the incident information and if a concern is triggered, additional analysis will be 

included in the risk assessment. 

Although aluminum phosphide had a low frequency of incidents in IDS, there was one incident 

that resulted in two deaths. In NO ISH SENSOR-Pesticides, aluminum phosphide had a 

moderately high frequency of incidents that were mostly moderate or low in severity. EPA has 

recently (20 1 0) expanded and clarified the outdoor use restrictions for all phosphine products 

used against burrowing rodents. Considering the newly required safety measures, the Agency 

will continue to monitor the incident information and provide an updated review of incidents 

during registration review. 

The Agricultural Health Study (AHS) is also a potential source of information associated with 

human health effects associated with certain pesticides. Magnesium phosphide and phosphine 

are not included in the AHS. Aluminum phosphide is included in AHS; however, because 

fumigant use is rare in the AHS population, there are no studies published that include aluminum 

phosphide. Therefore AHS does not provide information for this report. 

Detailed Review 

I. ACTION REQUESTED 

This review is intended to fulfill our requirement to docket summaries of incident data that were 

reported to the Agency, as well as to ensure human incident data and the Agricultural Health 

Study (AHS) are part of the problem formulation phase of registration review. Reports of 

adverse health effects allegedly due to a specific pesticide exposure (i.e., an "incident") are 

largely self-reported and therefore, generally speaking, neither exposure to a pesticide or 

reported symptom (or the connection between the two) is validated or otherwise confirmed. 

Typically, causation cannot be determined based on incident data. However, incident 

information can be an important source of feedback to the Agency: incidents of severe outcome, 

or a suggested pattern or trend among less severe incidents, can signal the Agency to further 

investigate a particular chemical or product. Observational epidemiology studies relate the risk 

of disease, e.g., cancer, and exposure to an agent such as a pesticide product in the general 

population or specific sub-groups like pesticide applicators. 

II. BACKGROUND 

Aluminum phosphide and magnesium phosphide liberate phosphine gas and are therefore 

clustered with phosphine for registration review. Phosphine is formulated as a pressurized gas. 

Aluminum and magnesium phosphide are formulated as impregnated materials, pellets/tablets, 

and granules which release phosphine gas upon exposure to atmospheric moisture. Phosphine 

fumigants are highly toxic pesticides that are restricted to use only by specially trained pesticide 

applicators. 

Phosphine is an insecticide/rodenticide labeled for use on numerous stored raw commodities (i.e. 

tree nuts, dried fruits, cereal grains), animal feed and feed ingredients, and processed foods (i.e. 

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candy, bakery mixes, crackers, cheese, meat products). Phosphine is also labeled for use on 

numerous non-food commodities and other non-food items. These include tobacco, cloth fibers, 

feathers, hair, wood and wood products, paper, tires, and beehives. Aluminum/magnesium 

phosphide pellets/tablets are used for rodent control, especially burrowing pests. Pellets or tablets 

are placed into the rodent burrows. However, these products may not be used in burrows that are 

within 100 feet of a building that is, or may be, occupied by humans and/or domestic animals. 

Indoor use of these products is prohibited. 1 

For this evaluation, both OPP Incident Data System (IDS) and the Centers for Disease Control 

and Prevention/National Institute for Occupational Safety and Health (CDC/NIOSH) Sentinel 

Event Notification System for Occupational Risk-Pesticides (SENSOR-Pesticides) databases 

were consulted for pesticide incident data on the active ingredient aluminum phosphide, 

magnesium phosphide and phosphine (PC Codes: 066501, 066504, 066500). The purpose of the 

database search is to identify potential patterns in the frequency and severity of the health effects 

attributed to aluminum phosphide, magnesium phosphide and phosphine exposure. 

In addition, findings from the AHS were reviewed. The Agricultural Health Study (AHS) is a 

high quality, prospective epidemiology study evaluating the link between pesticide use and 

various health outcomes including cancer. Magnesium phosphide and phosphine are not 

included in the AHS. Aluminum phosphide is included in AHS; however, because fumigant use 

is rare in the AHS population, there are no studies published that include aluminum phosphide. 

Therefore AHS does not provide information for this report. 

III. RESULTS/DISCUSSION 

a. IDS (Incident Data System) 

OPP's IDS includes reports of alleged human health incidents from various sources, including 

mandatory Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) Section 6(a)(2) reports 

from registrants, other federal and state health and environmental agencies, and individual 

consumers. Since 1992, OPP has compiled these reports in IDS. IDS contains reports from 

across the U.S. and most incidents have all relevant product information recorded. Reports 

submitted to the IDS represent anecdotal reports or allegations only, unless otherwise stated in 

the report. 

IDS records incidents.in one of two modules: Main IDS and Aggregate IDS: 

o Main IDS contains incidents resulting in higher severity outcomes and provides 

more detail with regard to case specifics. This system stores incident data for 

death, major and moderate incidents, and it includes information about the 

location, date and nature of the incident. Main IDS incidents involving only one 

active ingredient (as opposed to pesticide products with multiple active 

ingredients) are considered to provide more certain information about the 

potential effects of exposure from the pesticide. 

1 Prior to the new mitigation implemented in 20 I 0, pellets or tablets could not be used within 15ft of a building 

occupied by humans or domestic animals. 

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o Aggregate IDS contains incidents resulting in less severe human incidents (minor, 

unknown, or no effects outcomes). These are reported by registrants only as 

counts in what are aggregate summaries. 

Aluminum Phosphide 

For the Main IDS, from January 1, 2008 to February 19,2013, there were 3 incidents reported 

for single chemical only in the database. This incident was classified as major severity. These 

incidents are described further in Table 1. There was 1 additional incident reported involving 

more than one chemical. Overall, there are few incidents involving aluminum phosphide reported 

to IDS. 

In Aggregate IDS, from January 1, 2008 to February 19,2013, there were 6 reported incidents 

involving aluminum phosphide. These incidents were classified as minor severity. 

Table 1. Main IDS Major Incidents for the single chemical Aluminum Phosphide 

Human Incident Chemical: Aluminum Phosohide J PC Code: 066501 

Incident 

Package Reg Exposure 

Report Incident Date Location Number Product Name Severitv* Incident Description 

Four year old and 15 month 

old sisters died after the 

product was misapplied by a 

PCO within about 7 feet of 

the family residence (the 

pellets are not to be used 

within 15 feet of homes). 

The parents and siblings were 

021602- LAYTON, 072959- FUM I TOXIN also treated for flu-like 

00001 2/6/2010 UT 00002 PELLETS HA symptoms. 

Ten employees experienced 

nausea, eye irritation and 

chest discomfort and were 

transported to area ERs. 

They had been trying to 

extinguish a fire within a 

canvas bag that contained 

072959- 2200 lbs of pistachios 

021605- WASCO, 00002- FUMITOXIN undergoing fumigation with 

00005 12/1 0/2009 CA 005857 PELLETS HC the product. 

A male worker applying 

tablets to gopher holes 

experienced numbness on the 

left side of his body and 

became sick to his stomach. 

He was taken to the ER, 

examined and released. He 

was wearing gloves during 

the application and was 

022748 - KERMAN, 070506- WEEVIL-CIDE trained prior to the 

00001 l/20/2011 CA 00013 TABLETS HC application. 

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Exposure Severity* 

H-A 

H-B 

H-C 

Human Fatality 

Human M~or 

Human Moderate 

Death (if the person died) 

Major (if the person alleged or exhibited symptoms which may have been life-threatening, or resulted in adverse 

reproductive effects or in residual disability) 

Moderate (if the person alleged or exhibited symptoms more pronounced, more prolonged or of a more systemic 

nature than minor symptoms; and involved some form of treatment, even though symptoms were not life 

threatening and the person returned to his/her pre-exposure state of health with no additional residual disability) 

Magnesium Phosphide 

For the Main IDS, from January 1, 2008 to February 19, 20 13, there was 1 incident reported in 

the database. This incident was classified as minor severity. Overall, there are few incidents 

involving magnesium phosphide reported to IDS. 

In Aggregate IDS, from January 1, 2008 to February 19, 2013, there were no reported incidents 

involving magnesium phosphide. 

Phosphine 

For the Main IDS, from January 1, 2008 to February 19,2013, there was 1 incident reported in 

the database. This incident was classified as moderate severity. This incident is described 

further in Table 2. Overall, there are few incidents involving phosphine reported to IDS. 

In Aggregate IDS, from January 1, 2008 to February 19,2013, there were no reported incidents 

involving phosphine. 

Table 2. Main IDS Major Incidents for the single chemical Phosphine 

Human Incident Chemical: Phosphine I PC Code: 066500 

Incident 

Package Incident Reg Exposure 

Report Date Location Number Product Name Severity* Incident Description 

A male working was in a fumigated silo 

of nut crop and inhaled phosphine gas. 

He was admitted to the hospital and was 

observed for signs and symptoms of acute 

lung injury. An investigation revealed 

that the proper procedure was not 

followed because the sign placed on the 

silo had blown away. The sign should not 

have been removed until the commodity 

was completely aerated (contained 0.3 

VAPORPH30S ppm or less of phosphine gas). The case 

019519 068387- PHOSPHINE was exposed to 15 to 20 ppm of 

-00026 1/29/2008 CA 00008 FUMIGANT HC phosphine gas. 

Exposure Severity* 

Moderate (if the person alleged or exhibited symptoms more pronounced, more prolonged or of a more systemic nature than 

H-C Human Moderate minor symptoms; and involved some form of treatment, even though symptoms were not life threatening and the person 

returned to his/her pre-exposure state of health with no additional residual disability) 

b. SENSOR-Pesticides 

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The SENSOR-Pesticides database covers 11 states from 1999-2009, although reporting varies 

from state to state. Cases of pesticide-related illnesses are ascertained from a variety of sources, 

including: reports from local Poison Control Centers, state Department of Labor workers' 

compensation claims when reported by physicians, reports from State Departments of 

Agriculture, and physician reports to state Departments of Health. Although both occupational 

and non-occupational incidents are included in the database, SENSOR-Pesticides focuses on 

occupational pesticide incidents, and is of particular value in providing that information. A state 

SENSOR contact specialist attempts to follow-up with cases and obtains medical records to 

verify symptoms, circumstances surrounding the exposure, severity, and outcome. Using 

standardized protocol and case definitions derived from poison center reporting, SENSOR 

coordinators at State Departments of Health enter the incident interview description provided by 

the case, medical report, physician and patient into the SENSOR data system. The SENSORPesticides data system is accessible to participating states and EPA. 

Aluminum Phosphide 

A query of SENSOR-Pesticides 1998-2009 identifies 75 cases involving aluminium phosphide, 

stemming from 57 events. Seventy two cases involved a single active ingredient. Of these 

single active ingredient cases, there was one fatality that was resultant from a suicide; two high 

severity cases; 29 moderate severity cases and 50 low severity cases. The case detail for the high 

and moderate severity cases are provided in Table 3. Of the 72 single active ingredient cases, 66 

were work-related. Commonly reported symptoms include headache, dizziness, shortness of 

breath and cough. A breakdown of reported health effects is provided in Table 4. 

Multiple exposure events 

TX02769- In Texas in 2004, 7 warehouse workers were made ill after entering a warehouse 

fumigated with aluminum phosphide (Weevil-Cide pellets) the previous day. The case notes 

indicate the warehouse was not properly ventilated and the applicator failed to post warnings at 

all entrances. Applicator was cited with violations for making an application inconsistent with 

labeling and failure to provide [warning] signs. 

Table 3. SENSOR-Pesticides 1998-2009: Aluminum Phosphide Case Detail High and Moderate Severity Cases 

Case ID Severity* Year Narrative 

CA05595 Moderate 1999 Case detail not provided 

CA06456 Moderate 1998 Case detail not provided 

CA07330 Moderate 2000 Case detail not provided 

CA09402 Moderate 2001 Case detail not provided 

CA09874 Moderate 2002 Case detail not provided 

CA13812 Moderate 2004 Exposed when he wrapped up tarps that had chemicals on them 

CA13813 Moderate 2004 Was picking up pallets with his forklift when container burst and spilled 

aluminum phosphide on him 

CAI5341 Moderate 2008 Working with a bin of walnuts that had recently been fumigated, not wearing 

monitoring device, developed symptoms. 

Page 6 of 10 
Table 3. SENSOR-Pesticides 1998-2009: Aluminum Phosphide Case Detail High and Moderate Severity Cases 

Case ID Severity* Year Narrative 

CA17730 Moderate 2009 Exposed to aluminum phosphide fumes while eradicating gophers 

LA02276 Moderate ' 2005 transferring rice from truck to bin, exposed to aluminium phosphide; did not 

wear mask; no PPE worn or training provided; helping on a friend's farm 

OR0 1940 High 2009 Reports to PEST via translation that he applied this pesticide for mole 

extermination (he's not licensed); would drop tablet 

TX03315 Moderate 2001 Deputy heard an explosion at a grain coop, saw cloud of smoke and got out of 

vehicle, smelled strong odor. 

TX03786 Moderate 2003 Case works in a grainery and puts down phofume fumigation pellets every 

Friday to control rats. Concerned about chronic expos 

TX03831 Moderate 2001 Case entered warehouse to work after being fumigated the day before. 

TX03878 High 2004 Case removing pellets from plastic container, placing in 5 gallon barrels. 

Standing over barrels when activated by moisture outside 

TX03893 Moderate 2004 Case had gloves on, cleaned up the ashes of the chemical, was there between 

6:00 and 7:15a.m. 

TX03897 Moderate 2004 Case came to work at 6 a.m. on June I. Walked inside door, no tape, cleaned 

room until 8:30, 2 guys helped him take out signs 

TX04471 Moderate 2005 Fumigating barns w/hands. Breathing heavy, opened a bottle (of substance) 

and inhaled. Working hard for peanut harvest-no intervention 

WA01494 Moderate 2004 Patient inhaled fumes 

WA02288 Moderate 2006 A 75 y/o male was taken to the ER five days post exposure for gastrointestinal, respiratory and neurological symptoms. 

WA03118 Moderate 2009 Flash Explosion 

*SENSOR-Pesticides Severity Index 

Death Human Fatality 

High Life threatening, requires treatment >5 days lost work/time 

Moderate Involves systemic effects 3-5 days lost work/time 

Minor Symptoms typically resolve without treatment 

<3 days lost work/time 

Table 4. SENSOR-Pesticides 1998-2009: Reported Health 

Effects for Aluminum Phosphide Cases (N=72) 

Health Effect # of Times Reported 

Dermal I I 

Ocular 13 

Respiratory 50 

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Gastrointestinal 45 

Renal 1 

Nervous System 56 

Cardiovascular 20 

Misc. 18 

* Cases may report multiple health effects 

Magnesium phosphide 

A query of SENSOR-Pesticides 1998-2009 identifies 2 cases, stemming from 2 events, involving 

the single active ingredient magnesium phosphide. One case occurred in California in 1998 and 

was moderate in severity; however, no case details were recorded. The second case occurred in 

Washington in 2009 and was low in severity. According to the case description, this case was 

employed by a wholesale coffee company and was exposed as he "unloaded merchandise from a 

large container that was fumigated over the weekend. There was improper ventilation when the 

container was closed because of drizzle. He unloaded materials from the container over a 3 day 

period and developed fatigue and gastrointestinal health effects. He sought health care." 

Phosphine 

A query of SENSOR-Pesticides from 1998-2009 identifies 22 cases, stemming from 9 events, 

involving phosphine. Twenty one cases involved a single active ingredient and are further 

discussed below. Ten cases are moderate in severity and 11 are low in severity. All cases are 

work-related. One event in California in 2007 resulted in 14 case reports. The case information 

for these 14 cases reads "Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened." Case details for the 10 moderate severity phosphine 

cases are provided in Table 5. A summary of symptoms reported is provided in Table 6 below. 

The most commonly reported symptom was headache (n=14). 

Table 5. SENSOR-Pesticides 1998-2009: Phosphine Case Detail Moderate Severity Cases 

Case ID Severity* Year Case Narrative 

CA13933 Moderate 2004 Exposed to phosphine gas 

CA15346 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CA15354 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CA15402 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CA15406 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CA15713 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CAI5714 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

CA15716 Moderate 2007 Fumigant was trapped in a room that had not been ventilated, case 

exposed when the doors were opened 

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studies published that include aluminum phosphide. Therefore AHS does not provide 

information for this report. 

IV. CONCLUSION 

In 2010, EPA and the primary manufacturers of aluminum and magnesium phosphide pesticide 

products worked together to expedite the process of amending product labels to include the 

expanded use restrictions and reduce the potential for accidental poisonings. The new 

restrictions apply to all phosphine products for use against burrowing rodents. The expanded 

and clarified restrictions for these outdoor use products include prohibition of use in all 

residential areas and increased buffer zones (for a building that is or may be occupied with 

people or animals) from 15 to 100 feet. For more information regarding the expanded use 

restrictions visit: http :1 lwww .epa. gov I oppsrrd 1 /reregistration/ al phosphide/aluminum-magnsmphos-fs.html. 

For magnesium phosphide and phosphine there is relatively low frequency and severity of 

incident cases reported both IDS and NIOSH SENSOR-Pesticides, there does not appear to be a 

concern at this time that would warrant further investigation. The Agency will continue to 

monitor the incident information and if a concern is triggered, additional analysis will be 

included in the risk assessment. 

Although aluminum phosphide had a low frequency of incidents in IDS, there was one incident 

that resulted in two deaths. In NOISH SENSOR-Pesticides, aluminum phosphide had a 

moderately high frequency of incidents that were mostly moderate or low in severity. As stated 

above, EPA has recently (20 1 0) expanded and clarified the outdoor use restrictions for all 

phosphine products used against burrowing rodents. Considering the newly required safety 

measures, the Agency will continue to monitor the incident information and provide an updated 

review of incidents during registration review. 

The Agricultural Health Study (AHS) is also a potential source of information associated with 

human health effects associated with certain pesticides. Magnesium phosphide and phosphine 

are not included in the AHS. Aluminum phosphide is included in AHS; however, because 

fumigant use is rare in the AHS population, there are no studies published that include aluminum 

phosphide. Therefore AHS does not provide information for this report. 

Page 10 of 10 
Table 5. SENSOR-Pesticides 1998-2009: Phosphine Case Detail Moderate Severity Cases 

Case ID Severity* Year Case Narrative 

TX00997 Moderate 1999 Working in a grain elevator when he accidentally inhaled phosphine 

fumigant. Phosphine pellet was left on the floor. 

WA02976 Moderate 2009 A 45 y/o male employee of packing company came into contact with 

fumigant fumes after opening and entering an empty rail car. 

*SENSOR-Pesticides Severity Index 

High Life threatening, requires treatment 

>5 days lost work/time 

Moderate Involves systemic effects 3-5 days lost work/time 

Minor Symptoms typically resolve without treatment 

<3 days lost work/time 

High Life. threatening, requires treatment 

>5 days lost work/time 

Table 6. SENSOR-Pesticides 1998-2009: 

Reported Health Effects for Phosphine Cases 

N=066500 

Health Effect #of Times 

Reported 

Dermal 7 

Ocular 12 

Respiratory 13 

Gastrointestinal II 

Renal 5 

Nervous System 17 

Cardiovascular 6 

Misc. 9 

* Cases may report multiple health effects 

c. Agricultural Health Study (AHS) 

The AHS is a high quality, prospective epidemiology study evaluating potential links between 

pesticide use and various health outcomes including cancer. The AHS includes private and 

commercial pesticide applicators and their spouses. If there are AHS findings relevant to a 

particular pesticide going through registration review, the Agency will ensure they are 

considered in the problem formulation/scoping phase of the process and, if appropriate, fully 

reviewed in the risk assessment phase of the process. The AI-IS includes information on use of 50 

different pesticide active ingredients commonly used in agriculture. 

Magnesium phosphide and phosphine are not included in the AHS. Aluminum phosphide is 

included in AHS; however, because fumigant use is rare in the AHS population, there are no 

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