,


### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460
OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION



### MEMORANDUM Date: December 3, 2013 SUBJECT: MCPA (2-methyl-4-chlorophenoxyacetic acid): Tier I Review ofHuman Incidents PCCode:030501,030502,030516,030563,030564 Decision No.: 483034 Petition No.: NA DP Barcode: D415940 Registration No.: NA Regulatory Action: NA CaseNo.:NA RiskAssessment Type: NA TXRNo.:NA CAS No.: 94-74-6,3653-48-3,2039-46-5,26544-20-7, 29450-45-1 MRIDNo.:NA


### FROM:

THROUGH:

TO: 40CFR:NA


### Shanna Recore, Industrial Hygienist Toxicology and Epidemiology Branch Health Effect Division (7509P) and ElizabethEvans, Environmental Protection Specialist Toxicology and Epidemiology Branch HealthEffects Division (7509P) /\ 

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# / 7/ David Miller, Acting Branch

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1/v'i , Toxicology and Epidemiology Branch Health Effects Division (7509P) Alexandra LaMay, Risk Assessor Risk AssessmentBranchVII Health Effects Division (7509P) and K. Nguyen, Chemical Review Manager Risk Management & 

### Implementation Branch 1 Pesticide Re-evaluation Division (7508P) Summary and Conclusions Ver.Apr.08



### Based onthe low severity and relatively low frequency ofincident cases reported for MCPA (2- methyl-4-chlorophenoxyacetic acid), there does not appear to be a concern at this time that would warrant further investigation. However; due to the disproportionate amount and severity
Page 1of5ofWeed-B-GonMax Ready Spray (RegNo 000228-00424-000239) incidents the Agency will evaluate this product further during inthe Preliminary Risk Assessment.

Detailed Review I. ACTION REQUESTED This review is intended to fulfill ourrequirementto docket summaries ofincident datathat were reported to the Agency, as well as to ensure human incident data andthe Agricultural Health Study (AHS) are partofthe problem formulation phase ofregistration review. Reports of adverse health effects allegedly due to a specific pesticide exposure 

### (i.e., an "incident") are largely self-reported andtherefore, generally speaking, neither exposure to a pesticide or reported symptom (orthe connectionbetweenthe two) is validated or otherwise confirmed. Typically, causation cannotbe determined based onincident data. However, incident information canbe an important source offeedback to the Agency: incidents ofsevere outcome, or a suggested pattern ortrend among less severe incidents, can signal the Agency to further investigate a particular chemical orproduct. Observational epidemiology studies relate the risk ofdisease, 

### 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 MCPA is anherbicide inthe phenoxy orphenoxyacetic acid family that is usedpost-emergence for selective control ofbroadleafweeds. MCPA is registered for use on alfalfa, barley, clover, flax, lespedeza, oats, pasture and rangeland grass, peas, rye, trefoil, triticale, andwheat, as well as grass grown for s.eed, to control a wide spectrum ofbroadleafweeds. MCPA is also registered for use onturf, lawns, vines, rights-of-way, and forestry applications. Residential homeowners may use MCPA onlawns. 1 Forthis evaluation, boththe OPP Incident Data System (IDS) andthe Centers for Disease Control and Prevention/National Institute for Occupational Safety and Health (CDC/NIOSH) SentinelEventNotification Systemfor Occupational Risk-Pesticides (SENSOR) databases were consulted for pesticide incident data onthe active ingredient MCPA (PC codes: 030501, 030502, 030516, 030563, 030564). The purpose ofthe database search is to identify potential patterns in the frequency and severity ofthe health effects attributedto MCPA exposure. MCPA is not included in the AHS, and therefore this study does notprovide information for this report. III. RESULTS/DISCUSSION

a. IDS (Incident Data System) OPP's IDS includes reports ofalleged humanhealth 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

1Excerpt from MCPAFactsheet, found online at: http://www.epa.gov/ oppsrrd1/REDs/factsheets/mcpa red fs.pdf Page 2 of5 

### '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 informationrecorded. Reports submitted to the IDS represent anecdotal reports or allegations only, unless otherwise stated in the report. IDS records incidents in one oftwo modules: Main IDS and Aggregate IDS:



### o Main IDS contains incidents resulting inhigher severity outcomes andprovides more detail with regard to case specifics. This system stores incident data for death, major and moderate incidents, and itincludes information aboutthe location, date and nature ofthe 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 aboutthe potential effects ofexposure from the pesticide.



### o Aggregate IDS contains incidents resulting in less severe human incidents (minor, unknown, orno effects outcomes). These are reported byregistrants only as counts inwhat are aggregate summaries.

Forthe Main IDS, from January 1, 2008 to September 11, 2013, there were 0 incidents reported for single chemical only inthe database. There were 69 incident reported involving more than one chemical? Two incidents were classified as major severity; however, upon further review these incidents could not be directly linkedto the productused (Table 1 ). The other 67 incidents were classified as moderate severity. In Aggregate IDS, from January 1, 2008 to September 11, 2013, there were 324 reported incidents involving MCP A. Six incidents were classified as unknown orno effects and 318 incidents were classified as minor severity. Weed-B-Gon Max Ready Spray (Reg No 000228-00424-000239) appears to be implicated in a large number ofincidents inbothAggregate (83%) and Main IDS (97%). This product is used on residential lawns for weed control. In additionto MCPA (13.72%), this product contains the active ingredients Triclopyr (1.56%) and Dicamba (1.35%). This maybe potentially attributable to the high use ofthis product by consumers as reported inprivate market research studies and the Agency will considerthis possibilityto the extentpossible in future assessments. It should be noted that this product also appeared to have higher severity incidents than other comparable MCPA containing products.

2 There were also six incidents that occurred in Canada, 9 in England, 4 in Germany and 1in Ireland. Foreign incidents are notreviewed in detail because ofthe potential differences in the exposure patterns, use practices, and product formulation. Page 3 of5T bl 1 M . IDS M . In 'd t D a e am a,]or ct ens 

### 'f escnp11ons £ MCPA or Human Incident Chemical: MCPA PC Codes: 030501, 030502,030516, 030563, 030564**.~** •' Ic • 

## .. 'd _i ,lr '•:**~·** Incident Exposure 

### .. Package Incident Reg Severity RePOrt Date Location Number ProductName Codes IncidentDescription A 63 year old male has usedthis product every year for a few years onthe lawn. Theproduct sometimes gets on him and WEED-B-GON Major he rinses it off. He has experienced 000228- MAX READY urinary urgency, weight loss, and muscle 023382 00424- SPRAY 32 FL weakness. He has been to MDs, who -00030 9/112011 NJ 000239 

## oz cannot determine the cause. An unknown age male used the product outside. He did not wear a mask and he developed pain in his lungs. He was WEED-B-GON Major hospitalized the next day and diagnosed 000228- MAX READY with Multiple Myeloma and blood clots 024580 00424- SPRAY32 FL in his lungs. The MD does not believe it

- 00019 9/13/2012 ME 000239 

## oz is related to the product.


### b. SENSOR-Pesticides The SENSOR-Pesticides database covers 11 states from 1998-2009, although reporting varies from state to state. Cases ofpesticide-related illnesses are ascertained from a variety ofsources, including: reports from local Poison Control Centers, state Department ofLabor workers' compensation claims whenreported byphysicians, reports from State Departments of Agriculture, and physicianreports to state Departments ofHealth. Although both occupational and non-occupational incidents are included inthe database, SENSOR-Pesticides focuses on occupational pesticide incidents, and is ofparticular value inproviding that information. The state coordinator at each ofthe 11 respective state Departments ofHealth conducts case followup activities such as obtaining medical records to verify symptoms and severity. Using standardizedprotocol and case definitions derived from poison center reporting, the state SENSOR-Pesticide coordinator enters the incident information into the state-based system which is sentto NIOSH annually to be aggregated. A query ofSENSOR-Pesticides 1998-2009 finds 47 cases involving MCPA. Six cases involve a single active ingredient and 41 cases involve multiple active ingredients. Ofthe six single active ingredients cases, two were moderate in severity and four were lowin severity. Case symptoms are provided inTable 2.

Table 2. SENSOR-Pesticides 1998-2009: Reported HealthEffects for MCPA Cases

HealthEffect # ofTimes Re rted
Page 4 of5Dermal 3 Ocular 3 Respiratory 2 Gastrointestinal 3 Renal 0 Nervous System 4 Cardiovascular 0 Miscellaneous 2 

### *Cases may report multiple health effects 

### The first moderate severity case occurred in Washington State in 2002, the case is described as follows, "Threeteachers at Whittier Elementary School had symptoms after a strong herbicide odor entered the school ventilation system. The odor was from Superfund clean-up ofchemical manufacturing wastes buried in a nearby landfill. Air sampling data at site monitors detected MCPP. Reported student symptoms were not documented." This is also the case description for a low severity incident from the same event. Presumably only two ofthe three teachers mentioned experienced symptoms because there are only two SENSORcase reports. The second moderate severity case occurred in Texas in 1998 and is described as follows, "Farm hand/licensed applicator, applying pesticides for several years. He did not use protective equipment; developed symptoms."



### c. Agricultural Health Study (AHS) The AHS is a high quality, prospective epidemiology study evaluating the linkbetweenpesticide use and various health outcomes including cancer. The AHS includes private and commercial pesticide applicators and their spouses. Ifthere are AHS findings relevant to a particular pesticide goingthrough registration review, the Agency will ensure they are considered inthe problem formulation/scoping phase ofthe process and, ifappropriate, fully reviewed inthe risk assessmentphase ofthe process. The AHS includes information onuse of50 different pesticide active ingredients commonly used in agriculture. MCPA is not included inthe AHS, and therefore this study does not provide information for this report. 

### IV. CONCLUSION Based onthe low severity and relatively low frequency ofincident cases reported for MCPA in bothIDS and SENSOR-Pesticides, there does not appearto be a concern at this time that would warrant further investigation. However; due to the disproportionate amount and severity of Weed-B-Gon Max Ready Spray (RegNo 000228-00424-000239) incidents the Agency will evaluate this product further during in the Preliminary Risk Assessment.

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