UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

MEMORANDUM 

Date: November 7, 2013 

SUBJECT: Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine salt, Dimethylamine-2-(2,4-

dichlorophenoxy) propionate, Isooctyl 2-(2,4-dichlorphenoxy)propionate, 

Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 2,4-DP-p, 2-

ethylhexyl ester: Tier I Review of Human Incidents 

PC Code: 03 140 I ,03 1402,03 1403,031419, 

031463,03 1464,03 1465 

Decision No.: 481240 

Petition No.: NA 

DP Barcode: 0415950 

Registration No.: NA 

Regulatory Action: NA 

Risk Assessment Type: NA Case No.: NA 

TXRNo.: NA CAS No.: 120-36-5, 15165-67-0, 104786-87-0, 53404-32-3, 

28631 -35-8, 79270-78-3 

MRID No.: NA 40 CFR: NA 

Ver.Apr.08 

FROM: Shanna Recore, Industrial Hygienist A . II ~ . • A p- ... /,\ . n 

Toxicology and Epidemiology Branch \...).:t1A.JJJ 'y\ .... t-JJ_;(JJ,C/()A~ 

Health Effect Division (7509P) 

and 

Elizabeth Evans, Environmental Protection Specialist 

Toxicology and Epidemiology Branch 

Health Effects Division (7509P) Iii ;J 

THROUGH: David Miller, Acting Branch Chief . -1..;~/ ~~ Toxicology and Epidemiology Brand( 

Health Effects Division (7509P) 

TO: ldeliz Encarnacion, Risk Assessor 

Risk Assessment Branch V 

Health Effects Division (7509P) 

and 

Kaitlin Keller, Chemical Review Manager 

Risk Management & Implementation Branch 3 

Pesticide Re-evaluation Division (7508P) 

Page 1 of6 
Summary and Conclusions 

Based on the low frequency and severity of incident cases reported for Dichlorprop, 2,4-DP-p, 

2,4-DP-p, amine salt, Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-

dichlorphenoxy) propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 

2,4-DP-p, 2-ethylhexyl ester, 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. 

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

human health effects associated with certain pesticides. Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine 

salt, Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-dichlorphenoxy) 

propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 2,4-DP-p, 2-

ethylhexyl ester are 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 

Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine salt, Dimethylamine-2-(2,4-dichlorophenoxy) 

propionate, Isooctyl2-(2,4-dichlorphenoxy)propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-

, 2-ethylhexyl ester, and 2,4-DP-p, 2-ethylhexyl ester are all considered in this incident memo. 

Dichlorprop, Isooctyl 2-(2,4-dichlorphenoxy) propionate, and Propionic acid, 2-(2,4-

dichlorophenoxy)-, 2-ethylhexyl ester (PC Codes: 031401,031463, 031464) currently have no 

active registrations. These chemicals are herbicides used to control actively growing annual and 

perennial broad leaf weeds, trees, and brush. Their uses include lawns, golf courses, turf, sod 

farms, pasture, roadsides, industrial sites, forest lands, and rights of way. 

Page 2 of6 
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 ingredients Dichlorprop, 2,4-DP-p, 2,4-DP-p, 

amine salt, Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-

dichlorphenoxy)propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 

2,4-DP-p, 2-ethylhexyl ester (pc codes: 031401 ,03 1402,031403,03 1419, 031463,03 1464, 

031465). The purpose of the database search is to identify potential patterns in the frequency 

and severity of the health effects attributed to exposure from this group of chemicals. These 

chemicals are 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. It should be noted there are three incidents reported as lawsuits to IDS that are not 

considered in this 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. 

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, 2008 to June 11, 2013, there were no incidents reported for 

single chemical only in the database. However, there were 22 incidents reported involving more 

than one chemical. 1 One of these incidents was classified as major severity. This incident was 

1 There was also one moderate incident reported that occurred in England. Foreign incidents are not reviewed in 

detail because of the potential differences in the exposure patterns, use practices, and product formulation. 

Page 3 of6 
determined to be appendicitis and not related to active ingredient (further described in Table 1 ). 

Twenty one of these incidents were classified as moderate severity. 

In Aggregate IDS, from January 1, 2008 to June 11, 2013, there were 122 reported incidents. 

Overall, there are few incidents involving Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine salt, 

Dimethylamine-2-(2,4-dichlorophenoxy) propionate, lsooctyl 2-(2,4-dichlorphenoxy)propionate, 

Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 2,4-DP-p, 2-ethylhexyl ester 

reported to IDS. 

Table 1. Main IDS Major Incidents for Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine salt, 

Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-dichlorphenoxy)propionate, 

P ropwmc . . act "d , 2 -(2 , 4 -d" IC hl orop h enoxy ) -, 2 h -et y 11 1exy 1 ester, an d 2 , 4 -DP -p, 2 -et h y lh exy I es t er 

Chemical: Dichlorprop, 2,4-DP-p, 2,4-DPp, amine salt, Dimethylamine-2-(2,4-

dichlorophenoxy) propionate, Isooctyl 2-

(2,4-dichlorphenoxy)propionate, Propionic 

acid, 2-(2,4-dichlorophenoxy)-, 2-etbylhexyl PC Codes: 03 1401,031402,031403,031419, 

Human Incident ester, and 2,4-DP-p, 2-ethylbexyl ester 031463,031464.031 465 

Incident Exposure 

Package Incident Reg Severity 

Report Date Location Number Product Name Codes Incident Description 

A 68 year old male got some of the 

product on his hands while applying it. 

The product was on his hands for only 10 

TURF minutes and then it was washed off. The 

KANSAS 000239- BUILDER patient did not have any rubber gloves or 

020813 4/17/2009 CITY, 02640- WITH PLUS 2 HB a mask on when he applied the product. 

-00176 MO 000538 WEED Three hours later he experienced waves 

CONTROL of nausea and stomach cramping. He 

took some charcoal and vomited once. 

He had to have his appendix removed and 

his symptoms were unrelated to the 

product. 

b. SENSOR-Pesticides 

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-Pesticides focuses on 

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

state coordinator at each of the 11 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 annually to be aggregated. 

Page 4 of6 
TX03223 

TX03203 

TX03209 

TX032 10 

TX03213 

TX03219 

TX03225 TX01983 Exposed at work, lawn treaded the previous day, fumes seeped into the building via 

the vent. 

TX03228 

TX03229 

TX03230 

TX0323 1 

TX03232 

TX03218 

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 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 50 different pesticide 

active ingredients commonly used in agriculture. Dichlorprop, 2,4-DP-p, 2,4-DP-p, amine salt, 

Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-dichlorphenoxy)propionate, 

Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 2,4-DP-p, 2-ethylhexyl ester 

are not included in the AHS, and therefore this study does not provide information for this report. 

IV. CONCLUSION 

Based on the low frequency and severity of incident cases reported for Dichlorprop, 2,4-DP-p, 

2,4-DP-p, amine salt~ Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-

dichlorphenoxy)propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, and 

2,4-DP-p, 2-ethylhexyl ester in both IDS and 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. 

Page 6 of6 
A query of SENSOR-Pesticides indentifies 59 cases involving Dichlorprop, 2,4-DP-p; 2,4-DP-p; 

amine salt, Dimethylamine-2-(2,4-dichlorophenoxy) propionate, Isooctyl 2-(2,4-dichlorphenoxy) 

propionate, Propionic acid, 2-(2,4-dichlorophenoxy)-, 2-ethylhexyl ester, or 2,4-DP-p, 2-

ethylhexyl ester, stemming from 20 events, and only one single AI case. Case symptoms are 

summarized in Table 2 below. 

Table 2. SENSOR-Pesticides 1998-2009: Reported 

Health Effects for 2,4-DP Cases (N=59) 

Health Effect # of Times Reported 

Dermal 12 

Ocular 19 

Respiratory 40 

Gastrointestinal 26 

Renal 0 

Nervous System 44 

Cardiovascular 16 

Miscellaneous 2 

* Cases may report multiple health effects 

Ofthe 59 cases, one was high in severity, 16 were moderate in severity, and 42 were low in 

severity. The high severity case was a suicide attempt. Of the 16 moderate severity cases, 13 

cases occurred following one event in Texas in 2000. This event involved a total of 39 cases, 13 

moderate severity and the remaining 26 were low in severity. The case description for these 39 

cases is as follows, "Exposed at work, lawn treated previous day, fumes seeped in building via 

vent." 

The moderate severity cases and event descriptions are provided in Table 3 below. 

Table 3. SENSOR-Pesticides 1998-2009: 

Moderate Severity Case Descriptions for 2,4-DP Cases (N=l6) 

Case lD Event ID Narrative 

Certified applicator, maintenance for schools. No eye or resp. protection. Could be 

Ml00708 MI00630 heat related. Temp in van over 95. 

Man using weed & feed attachment on his hose when plastic on top of container split, 

NY00657 NY00454 drenching him. Tried another and had same result. 

WA0\1 76 WA00964 She said spray hit side of her truck/smelled spray 

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