UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

MEMORANDUM 

Date: February 20, 2013 

SUBJECT: Abamectin: Review of Human Incidents 

PC Code: 122804 DP Barcode: 0409003 

Decision No.: 473543 

Petition No.: NA 

Risk Assessment Type: NA 

TXRNo.:NA 

MRIDNo.:NA 

FROM: 

Registration No.: NA 

Regulatory Action: NA 

Case No.: NA 

CAS No.: 65195-55-3, 65195-56-4 

40CFR:NA 

Ver.Apr.08 

Shanna Recore, Industrial Hygienist A J /1 • • . 

Toxicology 

Health Effects 

and 

Division 

Epidemiology 

(7509P) 

Branch ~ 

and ~ 

Elizabeth Evans, Environmental Protection Specialist ~ L:. '--- ) 

Toxicology and Epidemiology Branch -~ 

THROUGH: 

TO: 

Health Effects Division (7509P) IJ ~ ;t{)- 6,6. lot$ 

David J. Miller, Acting Branch Chief ;j ~ilL ?" 

Toxicology and Epidemiology Branch 

Health Effects Division (7509P) 

Nancy Dodd, Risk Assessor 

Risk Assessment Branch III 

Health Effects Division (7509P) 

and 

K. Nguyen, Chemical Review Manager 

Risk Management & Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

Summary and Conclusions 

Based on the relatively low frequency and severity of incident cases reported for abamectin in 

both IDS and NIOSH SENSOR-Pesticides, there does not appear to be a concern that would 

warrant further investigation at this time. It is important to note that there were three incidents 

that occurred due to allergic reactions to the peanut products in the RAID Ant Baits (004822-

004 72 and 004822-00529). The Agency will continue to monitor the incident information, 

Page 1 of6 
particularly incidents involving allergic reactions to RAID Ant Baits II and III, and if a concern 

is triggered, additional analysis will be included in the risk assessment. 

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

human health effects associated with certain pesticides. Abamectin is not included in the AHS, 

and therefore this study 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 

Abamectin is an insecticide/miticide used to control mites, leaf miners, and other insects on 

various use sites including, but not limited to, citrus, cotton, grapes, strawberries, corn, soybeans, 

ornamentals, Christmas trees, and lawns. Abamectin acts as an insecticide by interfering with the 

nervous system of the insect, causing the insect to become paralyzed. 

It should be noted that Ivermectin (Abamectin) is also an anti-parasitic drug useful for treatment 

of internal (e.g. lymphatic filariasis, ascariasis, hook worms and cutaneous larva migrans) and 

external parasites (e.g. head lice, scabies) in human. It can be given orally or by injection 

(Ottesen and Campbell, 1994 ). The side effects of abamectin are related to the depression of the 

nervous system; particularly in children who have not developed a sufficient blood brain barrier. 

Therefore it is not indicated for children less than 5 years of age. Therapeutic dose is 150-200 

microgram/kg. Ingestion of2.5 -12 grams of abamectin has resulted in serious toxicity (Rumack 

BH Poisindex, 2013). 

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) databases were 

consulted for pesticide incident data on the active ingredient abamectin (PC Code: 122804). The 

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

the health effects attributed to abamectin exposure. 

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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. Abamectin is not included in the AHS, and therefore 

this study 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 it;1gredient (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. 

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. 

For the Main IDS, from January 1, 2007 to December 11,2012, there were 25 incidents reported 

for single chemical only in the database. There were 11 additional incidents reported involving 

more than one chemical. All of these incidents were classified as moderate severity. Overall, 

there are few incidents involving abamectin reported to IDS; however, it is important to note that 

there were three incidents that occurred due the cases having allergic reactions to the peanut 

products in the RAID Ant Baits II and III (004822-00472 004822-00529). These exposures 

occurred while handling or being exposed to products placed in the home (see Table 1 for more 

details). 

In Aggregate IDS, from January 1, 2007 to December 11,2012, there were 120 reported 

incidents involving abamectin. 

Page 3 of6 
T a bl e 1 M . . am IDS I nc1 "d enS t I nvo I VID2 . All Cr2IC . R eac ti on t o RAID A n t B a1 "t s 

Human Incidents Chemical: Abamectin PC Code: 122804 i •. 

, If I' 

"' Incident ~, ,·r 

,..,. 

' l'i, Pac!(age lpcident Registration Product Incident 

Report ,, Date Location Number Name Exposure Severity* Description . ~ 

A 7 year old 

female had an 

allergic reaction 

to the product in 

RAID the evening. Her 

DOUBLE mother had 

CONTROL placed the 

019835- 004822- ANT BAITS II product earlier 

00032 6/22/2008 GILBERT, AZ 00472 USA HC that day. 

A 5 year old 

female had 

allergic reaction 

to the peanut 

RAID ANT butter in the 

BAITS Ill traps that were 

019835- 3/29/2011 004822- USA (NON- set out in her 

00032 FRESNO,CA 00529 SPECIFIC HC home. 

A 30 year old 

female placed 

ant baits in her 

home. She has a 

peanut allergy 

and had an 

RAID ANT allergic reaction 

BAITS Ill to the bait which 

023313- 8/28/2011 NORTH 004822- USA(4 contains 

00028 PORT, FL 00529 COUNT) HC derivatives. 

Page 4 of6 
b. NIOSH SENSOR 

The SENSOR-Pesticides database covers 11 states from 1998-2009, 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 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 SENSOR data system 

is accessible to participating states and EPA. 

A query of SENSOR-Pesticides 1998-2009 identifies 147 cases stemming from 43 events. 

Ofthe 147 cases, 18 involved the single active ingredient abamectin and the remaining 129 cases 

involved exposure to multiple active ingredients. 137 cases (93%) were exposed at their 

workplace. One case was classified as high severity, 19 cases were classified as moderate 

severity and 127 were classified as low severity. The one high severity case was occupational 

and occurred in Washington in 2002. This exposure event is described as follows, "A 55 y/o 

male construction worker developed respiratory and dermal allergic reaction after he alleged 

contact from insecticide." 

A breakdown of symptoms for all abamectin cases reported is provided in the Table 2 below. 

Table 2. SENSOR-Pesticides 1998-

2009: Reported Health Effects for 

Abamectin Cases* 

Dermal 30 

Ocular 102 

Respiratory 94 

Gastrointestinal 121 

Renal 8 

Nervous System 125 

Cardiovascular 17 

Misc. 15 

* Cases may report multiple health 

effects 

Multiple case events 

Page 5 of6 
In Louisiana in 2003, 58 cases were reported following one work-related event. In this event a 

building was evacuated following an application of multiple products. The individuals went to 

the ER complaining of nausea, upper respiratory irritation and ocular pain. 

In California in 1998, 41 cases were reported following one work-related event involving 

exposure to multiple pesticide products. This event occurred in Fresno County where a crew of 

field workers became ill while weeding in a cotton field sprayed with pesticides 2 hours earlier. 

They were taken to a medical clinic complaining of symptoms (including neurological, 

gastrointestinal, cardiovascular, dermal, and ocular). Violations were recorded pertaining to 

early reentry and 'other misuse.' 

c. Agricultural Health Study (AHS) 

The AHS is a high quality, prospective epidemiology study evaluating the link 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 formulationlscoping phase of the process and, if appropriate, fully reviewed in the risk 

assessment phase of the process. The AHS includes information on use of 50 different pesticide 

active ingredients commonly used in agriculture. 

Abamectin is not included in the AHS, and therefore this study does not provide information for 

this report. 

IV. CONCLUSION 

Based on the relatively low frequency and severity of incident cases reported for abamectin in 

both IDS and NIOSH SENSOR-Pesticides, there does not appear to be a concern that would 

warrant further investigation at this time. It is important to note that there were three incidents 

that occurred due to allergic reactions to the peanut products in the RAID Ant Baits (004822-

004 72 and 004822-00529). The Agency will continue to monitor the incident information, 

particularly incidents involving allergic reactions to RAID Ant Baits II and III, and if a concern 

is triggered, additional analysis will be included in the risk assessment. 

References: 

Rumack BH POISINDEX(R) Information System Micromedex, Inc., Englewood, CO, 2013; 

CCIS Volume 156, edition expires May, 2013. HallAH & Rumack BH (Eds): TOMES(R) 

Information System Micromedex, Inc., Englewood, CO, 2013; CCIS Volume 156, edition 

expires May, 2013 

(http:/ /toxnet.nlm.nih. gov I cgi -bin/sis/ search/ a? dbs+hsdb: @term+@DOCN 0+6941) 

Ottesen EA, Campbell WC. Review Ivermectin in human medicine. Journal of Antimicrobial 

Chemotherapy. 1994:(34 ): 195-203. 

(ftp://ftp.puce.edu.ec/Facultades/CienciasExactas/PE/Helminths/Ivermectin%20in%20human%2 

Omedicine.pdt) 

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