UNITED ST ATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

MEMORANDUM 

Date: November 17, 20 15 

SUBJECT: Strychnine: Tier I (Scoping) Review of Human Incidents and Epidemiology 

PC Code: 076901 OP Barcode: 0430176 

Decision No.: 5111 55 

Petition No.: NA 

Risk Assessment Type: A 

TXR No.: A 

MRID No.: NA 

Registration No.: NA 

Regu latory Action: NA 

Case No.: A 

CAS No.: 57-24-9 

40 CFR: A 

Vcr.Apr.08 

FROM: Shanna Recore, Industrial Hygienist (} ,.. ,. El . /1 . 

Toxi

Hea lth 

cology 

Effect 

and 

Divi

Epidem

sion (7509

iology 

P) 

Branch ~~ ~ 

THROUGH: 

TO: 

and 

Eli zabeth Evans, Environmental Protection Specialist s--· . Toxicology and Epidemiology Branc/Jh 

Health Effects Division (7509P) i#t 

David Miller, Acting Branch Chi ef Y, ;j !flt 

Toxicology and Epidemiology Branch 

Hea lth Effects Division (7509P) 

Jamie D' Agostino, Risk Assessor 

Risk Assessment Branch II 

Health Effects Division (7509P) 

and 

Susan Bartow, Chemical Review Manager 

Risk Management & Implementation Branch 2 

Pesticide Re-evaluation Division (7508P) 

Summary and Conclusions 

(}> / ..!}/Iv./. l. J t.J 

Based on the low frequency of incident cases reported for strychnine in both IDS and SENSORPesticides there does not appear to be a concern at this time that would warrant further 

investigation. The Agency wi 11 continue to monitor the incident information and if a concern is 

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

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Detailed Review 

I. ACTION REQUESTED 

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

reported to the Agency, as well as to ensme 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 

infom1ation 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 

Strychnine is currently registered for use only below-ground as a bait application to control 

pocket gophers. The end-use products are fonnulated as a grain-based bait or a paste. Baiting can 

be done manually, or with the use of application equipment. Typical application equipment 

includes a burrow-builder, which digs artificial tunnels; or an impinger, which "injects" bait into 

the animal's tunnel. 1 

For this evaluation, both the 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 strychnine (pc code: 128997). The 

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

the health effects attributed to strychnine exposure. Strychnine 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. 

1 http://www.epa.gov/pestic ides/reregistration/REDs/factsheets/3 13 3 fact. pdf 

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

o Ma in JDS contai ns 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 inc ludes 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. 

o Aggregate IDS contai ns 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 JDS, from January I, 2010 to May 27, 2015, there were 3 incidents reported for the 

single chemical strychnine only in the database. One incident was involved three teenagers who 

snorted strychnine mistaking it for cocaine. Two of the individuals were classified as major 

severity and the third individual died. The other two incidents were classified as moderate 

severity. There were no additional incidents reported involving than one chemical. 

In Aggregate IDS, from January 1, 20 10 to May 27, 2015, there were 3 incidents reported 

involving strychnine. These incidents were classified as minor severity. Overall, there are few 

incidents reported to IDS involving strychnine. 

b. SENSOR-Pesticides 

The SENSOR-Pesticides database covers 12 states from 1998-201 1, 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. The 

state coordinator at each of the 12 respective state Departments of Health conducts case followup activities such as obtaining medical records to verify symptoms and severity. Using 

standardized protocol and case definitions derived from poison center reporting, the state 

SENSOR-Pesticide coordinator enters the incident information into the state-based system which 

is sent to NIOSH annuall y to be aggregated. 

A query of SENSOR-Pesticides 1998-2011 identifies ten cases involving strychnine, nine of 

which involve a single a i. One case was fa tal as a result of suic ida l ingestion. Of the remaining 

e ight single ai cases, one case was high severity, three cases were moderate in severity and four 

cases were low in severity. Little information is provided for the high severity case, but this case 

was admitted to a hospital and experienced renal failure. The high severity case activity at the 

time of exposure is unknown. Five cases were work-related. Four of the five work-related cases 

were mixing/loading or handling the product. 

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Six cases reported various neurological symptoms primarily dizziness (n=3). Four cases 

reported gastrointestinal symptoms, three cases reported dermal symptoms and three cases 

reported respiratory symptoms. 

c. Agricultural Health Study (AHS) 

The ABS is a high quality, prospective epidemiology study evaluating the link between pesticide 

use and various health outcomes including cancer. The ABS includes private and commercial 

pesticide applicators and their spouses. If there are ABS 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 AHS includes information on use of 80 different pesticide 

active ingredients commonly used in agriculture. Strychnine is not included in the AHS, and 

therefore this study does not provide information for this report. 

IV. CONCLUSION 

Based on the low frequency of incident cases reported for strychnine in both IDS and SENSORPesticides there does not appear to be a concern at this time that would wanant further 

investigation. The Agency will continue to monitor the incident info1mation and if a concern is 

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

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