Health & Safety

Analysis of The Impact of the Federal Worker Protection Standard and 

Recommendations for Improving California's Worker Protection Program 

Regarding Field Posting 

Janet R. Spencer, Associate Environmental Research Scientist 

November 2, 2001 

CALIFORNIA ENVIRONMENTAL PROTECTION AGENCY 

DEPARTMENT OF PESTICIDE REGULATION 

1001 I STREET SACRAMENTO, CA 95814 

Worker Health and Safety Branch Report

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Table of Contents Page 

Executive Summary 4 

Acronym Glossary 6 

Introduction 6 

Analysis of the Impact of WPS on California Regulations 7 

Background and Definitions 7 

Changes to California Regulations Following WPS 8 

Methods 8 

Results 8 

Analysis of the Impact of WPS on Pesticide-Related Illnesses and Attributes 11 

Methods 11 

Results 12 

 Analysis of Reduced-Protection Pesticides 12

Analysis of Frequency Rates and Task Distribution 13

 Analysis of Episode Rates by Crop 14

 Analysis of Frequency Rates by Pesticide 15 

 Analysis of Priority Episodes 15 

 Analysis of Reentry Violations and Probable Causes of Early Reentry 17 

Summary of Meetings and Workshops with Farmworker Advocate Organizations, CACs, 20 

 California Legislature, Representatives of the Agricultural Production Community 

 and US EPA 

Summary of Recommendations on Posting Requirements from Farmworker 21 

 Advocate Organizations 

Summary of CAC Response to Farmworker Advocate Organizations’ Recommendations 22 

 on Posting Requirements 

Summary of Comments from DPR Workshops with Agricultural Production Stakeholders 23 

WH&S Recommendations 24 

 Issue 1: Identify and evaluate the impact of any reduced-protection pesticides post-WPS 24

 Issue 2: Evaluate and identify trends in PISP data which indicate WPS-related effects on 24 

 illness frequency rate. 

 Issue 3: Identify the probable causes of reentry violations; propose appropriate 25 

 mitigations 

 Issue 4: Evaluate expanding field posting to all pesticides and restricted entry intervals 26

 of any length as an improvement to the current field posting requirements. 

 Issue 5: Identify and evaluate problems in complying with posting requirements 26

References 27 

Index to Tables Page 

Table 1. Restricted Entry Interval (REI) and Posting Requirements Pre-WPS vs. Post-WPS 9 

Table 2. Summary of Illness Episodes 1991 – 1999 with a Definite or Probable Relationship 12 

 to a Pesticide, and Determined to Involve Six Pesticides with Reduced Protections Post-WPS 

 as Causal or Contributory to the Illness 
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Table of Contents, cont. Page

Index to Tables, cont. 

Table 3. Summary by Task for Number of Pesticide Illness Surveillance Program 13 

 Episodes Probably or Definitely Related to Pesticides and Involving Agricultural Workers 

 Exposed to Field Residues, 1991 – 1999, and Number of Persons Involved in Each Episode 

 and Involving Agricultural Workers Exposed to Field Residues, 1991 – 1999

Table 4. Definite and Probable Pesticide-Related Episodes Involving Agricultural Workers 14 

 Exposed to Field Residues, with No Reentry Violations, by Crop and Task, 1991 - 1999 

Table 5. Summary of the Distribution of Priority Illness Episodes, 1991 – 1999 16 

 Number of Episodes and Persons for Definite and Probable Pesticide-Related 

 Episodes Involving Agricultural Workers Exposed to Field Residues 

Table 6. Summary of the Number of Priority Episodes by Task, 1991 – 1999, for Definite 16 

 and Probable Pesticide-Related Episodes Involving Agricultural Workers Exposed 

 to Field Residues 

Table 7. Summary Statistics by Task for 106 Illness Episodes, 1991 – 1999, for Definite 17 

 and Probable Pesticide-Related Episodes Involving Agricultural Workers Exposed to Field 

 Residues: Count of Reentry/Early Entry Restriction Violations, Other Violations 

 and No Violations 

Table 8. Combined Totals for Probable Causes of 47 Illness Episodes 19 

 with Reentry Violations, 1991 – 1999, for Definite and Probable Pesticide-Related 

 Episodes Involving Agricultural Workers Exposed to Field Residues 

Table 9. Number of Compliance and Enforcement Actions Taken in Response to 20 

 47 Illness Episodes with Reentry Violations Which Involved Agricultural Workers 

 Exposed to Field Residues, 1991 – 1999 
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Executive Summary 

The revised federal Worker Protection Standard (WPS), effective since 1995, was modeled 

substantially after California's comprehensive worker protection program (1,2,3). Although the 

California program exceeded the federal standard in several areas, US EPA determined it did not 

meet certain aspects of the federal standard. California thus adopted regulation changes to 

implement the federal WPS in California in December of 1996 (4). These regulations became 

fully effective January 1, 1997. 

WPS sets requirements for employers of both pesticide handlers (those who mix, load or apply 

pesticides) and agricultural workers (those doing hand labor tasks or irrigation). This report 

summarizes the evaluation of specific requirements for agricultural workers (fieldworkers). One 

set of requirements is commonly called “notification requirements”. These specify that 

employers prevent fieldworkers’ unsafe entry into treated fields by notifying them orally of 

recent pesticide applications and, if applicable, the number of days during which entry is 

prohibited (restricted entry intervals or REIs). The REI is intended to allow pesticide residues to 

dissipate to levels which do not pose a health hazard to workers. In addition to oral warnings, 

specific crops treated with certain pesticide products are required to be posted with warning signs 

which prohibit entry for the duration of the REI (field posting). WPS also requires that 

employers provide workers with hazard communication information, pesticide safety training, 

personal protective equipment (PPE), decontamination supplies, and emergency medical 

assistance. 

In 1999, the California Department of Pesticide Regulation (DPR), Worker Health and Safety 

Branch (WH&S) began assessing the worker protection program in response to concerns held by 

both DPR and worker advocate organizations about the adequacy of notification, field posting, 

and hazard communication requirements (5). County agricultural commissioners (CACs) and 

agricultural production groups also participated in this assessment. This report summarizes 

WH&S’ evaluation of the impact of WPS on California regulations and pesticide-related 

illnesses, evaluates the effectiveness of current field posting requirements, and provides 

recommendations to improve California’s worker protection regulations. The notification and 

hazard communication components of California’s worker protection program will be evaluated 

in a separate report. 

While California’s earlier worker protection program (pre-WPS) based requirements for REIs 

and field posting on product toxicity, the federal WPS based these requirements on the toxicity 

of the pesticide’s active ingredient. As a result, incorporating the federal WPS into California 

regulation (post-WPS) changed the REI and/or posting requirements for a number of pesticides. 

WH&S evaluation of California’s worker protection regulations identified six pesticides which 

had less stringent protections post-WPS compared to pre-WPS. For these six pesticides, four 

illness episodes unrelated to early reentry occurred post-WPS. The underlying cause for three of 

the four episodes was related to a change in the pre-harvest interval. The cause of the fourth 

episode was not related to WPS changes. The regulatory changes do not appear to have 

increased the inherent hazard potential of these six pesticides. 
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Evaluation of the impacts of WPS on fieldworker pesticide-related illnesses focused on 

frequency rates by agricultural work task, crop, and pesticide. No WPS-related impacts were 

found. WH&S also evaluated reentry violations involved in pesticide-related illnesses and 

probable causes of early reentry. While no WPS-related impacts were identified, irrigation tasks 

appear to have a greater potential for pesticide-related illness than do other fieldworker tasks. 

Lack of notification and failure to wear required personal protective equipment were identified 

as the leading causes of reentry violations. While data for the most recent years (1997 to 1999) 

show a slight decline in the number of illness related to these two causes, WH&S plans to 

conduct further study of these issues. 

The rate that agricultural civil penalties (fines) were proposed in response to illness episodes 

involving reentry violations has risen steadily over the nine-year period, from 20 percent in 

1991 – 1994, to 53 percent during 1995 – 1996, to 70 percent in 1997 - 1999. During this time, 

DPR and the CACs have worked together closely to improve communication and program 

coordination. While we will continue efforts to deal vigorously and consistently with those 

responsible for reentry violations associated with documented illness, these data signal that DPR 

and the CACs are committed to fulfilling key health and safety components of their enforcement 

programs. 

WH&S recommendations for improving the worker protection regulations include stricter 

enforcement of existing regulations, evaluation of compliance with current posting requirements, 

review of compliance and enforcement actions related to reentry violations, evaluation of the 

adequacy of CAC enforcement guidelines, training and outreach to improve compliance with 

current posting requirements, and evaluation of ways to improve field posting sign availability 

and durability. DPR plans to address these recommendations by the following work plan: 

! Fall 2001: Present the findings to the CACs. Emphasize the importance of conducting 

outreach/training on the notification and posting requirements and enforcing reentry 

violations. 

! Fall 2001: Meet with worker advocate organizations to discuss the findings, and send an 

enforcement letter to the CACs identifying notification and posting requirements as a high 

priority for outreach/training and inspection activity. 

! Winter 2001: Meet with agricultural production groups to discuss the findings. 

! Winter 2001: Develop and distribute compliance assistance materials on notification and 

posting requirements. 

! June 2002: Complete evaluation of notification and hazard communication requirements. 

! December 2002: Establish a compliance baseline to determine whether outreach/training and 

enforcement actions improve compliance trends. 

! January – June 2003: Complete evaluation of the impact of the above steps on compliance 

with notification and posting requirements and/or reduced illnesses associated with reentry 

violations. Consider regulatory changes if trends remain unchanged. 
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Acronym Glossary 

3 CCR California Code of Regulations, Title 3, Division 6, which contains the state’s 

worker protection regulations 

a.i. Pesticide active ingredient 

ACP agricultural civil penalty, an enforcement action which DPR and the County 

Agricultural Commissioners can take in response to violations of 3 CCR and/or 

the California Food and Agriculture Code 

CAC California County Agricultural Commissioner(s), DPR’s local enforcement agents 

DPR California Environmental Protection Agency, Department of Pesticide Regulation 

FAC California Food and Agriculture Code 

PISP Pesticide Illness Surveillance Program, California Department of Pesticide 

Regulation, Worker Health and Safety Branch 

PPE Personal protective equipment 

REI Restricted entry interval 

VN violation notice, a compliance action which DPR and the CAC 

 can take in response to violations of 3 CCR and/or the California FAC 

WH&S California Department of Pesticide Regulation, Worker Health and Safety Branch 

WPS federal Worker Protection Standard 

US EPA United States Environmental Protection Agency 

Introduction 

The revised federal Worker Protection Standard (WPS) regulation was issued by the U. S. 

Environmental Protection Agency (US EPA) in 1992, and became fully effective on January 1, 

1995 (1). The WPS was put in place to reduce the occupational risk of pesticide poisonings and 

injuries among agricultural workers on farms, and in forests, nurseries and greenhouses. The 

WPS contains requirements for pesticide safety training, notification of pesticide applications, 

use of personal protective equipment (PPE), decontamination supplies, and emergency medical 

assistance. The WPS was modeled substantially after California's comprehensive worker 

protection program (2,3). Although the California program exceeded the federal standard in 

several areas, US EPA determined it did not meet certain aspects of the federal standard. In 

December of 1996, California adopted regulation changes to implement the federal WPS in 

California (4). These became fully effective January 1, 1997. 

In 1999, the California Department of Pesticide Regulation (DPR), Worker Health and Safety 

Branch (WH&S) began assessing the worker protection program in response to concerns held by 

both DPR and worker advocate organizations about the adequacy of notification, field posting, 

and hazard communication requirements (5). The assessment effort gained visibility and 

momentum in 2000, when the California Assembly Agricultural Committee requested that DPR 

evaluate the adequacy of California’s field posting regulations (6). 

The US EPA began a national assessment of the WPS program in 2000. DPR participated in the 

federal stakeholder workshop held in Sacramento in December 2000. In February 2001, the 

WH&S assessment of the worker protection program was incorporated by amendment into the 

US EPA/DPR Federal Work Plan as the Pesticide Illness Surveillance Program (PISP) Data 
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Analysis Project (7). Findings from the WH&S assessment will be shared with the US EPA 

Office of Pesticide Program representatives working on the national assessment. 

This report summarizes WH&S’ evaluation of the impact of WPS on California regulations and 

pesticide-related illnesses and attributes. It also evaluates the effectiveness of current field 

posting requirements. While the data analyses are specific to California, recommendations for 

improving the regulations apply to both the California and federal WPS. The WH&S assessment 

includes the following components: 

! Analysis of the impact of WPS on California regulations, 

! Analysis of the impact of WPS on pesticide-related illnesses, 

! Summary of comments and recommendations from WH&S workshops and meetings with 

worker advocate organizations, agricultural production stakeholders, and county agricultural 

commissioners, and 

! Recommendations for improving California and federal field posting protections and 

regulations. (Notification and hazard communication requirements will be evaluated at a later 

date in a separate report.) 

Analysis of the Impact of WPS on California Regulations, 1991 –1999 

Background and Definitions 

In the 1970’s, California adopted worker protection regulations which DPR has expanded and 

refined in a continual effort to mitigate the hazards of workplace exposure to pesticides (2,3). 

One program component set longer restricted entry intervals (REIs) than specified on the 

pesticide product label, following certain pesticide applications. The REI is intended to allow 

pesticide residues to dissipate to levels which will not pose a health hazard to workers. Thus, 

most work activities are prohibited during the REI. Permitted activities may be subject to 

additional restrictions such as maximum time allowed in the treated field or require wearing 

personal protective equipment (PPE). Another WPS regulatory component, worker notification, 

required that workers be orally warned of pesticide applications to areas which they were 

anticipated to enter during an application, or during the REI. 

In addition to oral warnings, specific crops treated with certain pesticide products were required 

to be posted with warning signs for defined time periods following application (field posting). 

Prior to 1986, “long-term” field posting applied to all crops following application of a pesticide 

with an REI greater than 7 days. In 1986, California established additional “short-term posting” 

regulations for 13 crops. This regulation was based on crop-specific factors including illness 

frequency rates per acre, amount of pesticide applied, type and time periods of hand cultural 

practices, high numbers of systemic illnesses or dermatitis cases, use of pesticides with a high 

acute dermal toxicity, and time periods of high pesticide use (8). 

Pesticide registrants evaluate every pesticide product as meeting criteria for toxicity category I, II 

or III (category I is the most toxic) and display the category’s corresponding signal words 

(danger, warning or caution, respectively) on the pesticide label (1). For eight of the thirteen 

crops, “short-term” field posting was required when any pesticide product in toxicity category I, 

with an REI of two days or more, was applied (8). The same requirement applied to the 

remaining five crops following applications from April 15 through harvest. Existing regulations 
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specifying longer REIs following certain pesticide applications and requiring a minimum oneday REI following applications of pesticide products in toxicity category I were retained. The 

previous requirement for long-term field posting also remained in effect. 

Changes to California Regulations Following WPS 

The federal WPS became fully effective in 1995 (1). From 1995 through December 1996, both 

the WPS and existing California regulations were in effect. The adoption of the federal WPS into 

California regulation in 1997 expanded prior California restrictions on worker notification, field 

posting and REIs. Instead of specifying long- or short-term field posting based on pesticide 

product toxicity, the new regulations based field posting requirements on the toxicity of the 

pesticide product’s active ingredient(s) (a.i.). WPS requires “dual notification” (both oral 

notification and posted warning signs) of workers following application of a pesticide product 

whose a.i. meets toxicity category I criteria for acute dermal toxicity, eye irritation effects or skin 

irritation effects (dermal/eye/skin). As a result, field posting requirements were increased for 

some pesticides (increased protection pesticides), but reduced for a few toxicity category I 

products whose a.i. did not meet toxicity category I dermal/eye/skin criteria (reduced protection 

pesticides). For pesticide applications not subject to dual notification, employers are required to 

provide workers either oral or posted notification. For all pesticide applications, worker 

notification was expanded to include any employee likely to be walking within one-quarter mile 

of the treated field during the application or the REI. 

The WPS also established new regulations for REIs, setting these on an interim basis until the 

scientists completed further evaluation of each pesticide. If a pesticide product contains a single 

a.i. which meets toxicity category I dermal/eye/skin criteria, then the REI is 48 hours. If, in 

addition, the a.i. is an organophosphorous ester that inhibits cholinesterase, and is applied 

outdoors, then the REI is 72 hours. If the pesticide product’s single a.i. meets toxicity category 

II or III dermal/eye/skin criteria, the REI is 24 hours and 12 hours, respectively. Other criteria 

apply for pesticides containing multiple a.i. As noted above for the impact of WPS on field 

posting regulations, many REIs increased (enhanced protections), while some were reduced 

(reduced protections). 

Methods 

WH&S analyzed the California worker protection regulations pre-WPS (1991 – 1994) and postWPS (1997 – 1999) to ascertain whether changes in posting, notification and REI resulted in any 

reduced protections compared to the pre-WPS regulations (2). WH&S examined pesticides 

previously subject to short-term posting regulations, those with longer REIs than specified on the 

pesticide product label, organophosphate pesticides, toxicity category I pesticide products, 

pesticides typically involved in illness episodes, and pesticides among the top 100 used statewide 

(9 - 14). Pesticide labels on file with DPR were also examined. 

Results 

Table 1 displays the results of WH&S analyses. The majority of pesticides examined (27 a.i.) 

had either more restrictions or no change following WPS. However, six pesticides were 

identified as having reduced protections post-WPS. Methidathion and methomyl now require 

posting only for REIs greater than 7 days, while prior California short-term posting regulations 
Table 1. Restricted Entry Interval (REI) and Posting Requirements Pre-Worker Protection Standard1 (W

 Toxicity Category OP Restricted Entry Interval 

Change2

+/0/- Active Ingredient3,4

Product 

Label5

Dermal/ 

Eye/Skin (a.i.)6

Current 6772(b) 

specifies crop(s) 

ChE Inhib7 Pre-1995 Post-1995 P

+ acephate II/III <I No Yes 

<1 day 1 day 

+ aldicarb I I No No 1 day 2 days 

0 azinphos-methyl9 I I all crops Yes >14 days >14 days 0 bifenthrin I <I No No no products 1⁄2 day no 

+ carbofuran I I No No 1-14 days 2-14 days Ye

>

0 chlorpyrifos9 II <I citrus Yes <2 days <2 days 

- cyfluthrin I <I No No 1 day 1/2 day 

0 diazinon9 II <I >2 crops Yes <5 days <5 days 

+/- dimethoate I/II/III <I No Yes 

<2 days 2 days Yes

an

0 diquat II <I No No 1 day 1 day 

+ disulfoton I I corn Yes 2 days 3 days + endosulfan9 I I all crops No 2 days 2 days + ethephon I I No Yes 1 day 3 days + fenamiphos I <I No Yes 1 day 2 days + fenbutatin-oxide I <I flowers No 1 day 2 days 

0 glyphosate II/III <I No No <1⁄2 day <1⁄2 day 

+ malathion II/III <I >2 crops Yes 

<1 day 1-3 days 

+ methamidophos I I No Yes 2 days 3 days 

- methidathion9 I <I citrus Yes 2-30 days 2-30 days Ye

>

+/- methomyl9 I <I grapes No 1-21 days 2-21 days Ye

>

+ naled I <I No Yes 1 day 1-3 days 
Table 1. Restricted Entry Interval (REI) and Posting Requirements Pre-Worker Protection Standard1 (W

cont. 

 Toxicity Category OP Restricted Entry Interval 

Change2

+/0/- 

Active Ingredient3,4 Product 

Label5 

Dermal/ 

Eye/Skin (a.i.)6

Current 6772(b) 

specifies crop(s) 

ChE Inhib7 Pre-1995 Post-1995 

- oxamyl I <I No No >1 day 2 days Y

+ oxydemeton-methyl II <I >2 crops Yes 1 day 3 days 

0 paraquat I <I No No < 2 days <2 days 0 parathion-methyl9

(non-encapsulated) 

II <I >2 crops Yes 14-21 days 14-21 days Y

- phorate9 I <I corn Yes 2-7 days 2-7 days Y

+ phosmet9 II <I >2 crops Yes 1-5 days 1-5 days 

0 propargite9 I I >2 crops No 3-42 days 3-42 days 

+ sodium 

tetrathiocarbamate 

I <I No No 2-4 days 4 days 

+ sulfotep I I No Yes 

< 2 hours 1 – 2 days 

+ sulfur9 II/III <I grapes No 

<1-3 days 1 –3 days 

+ tribufos I <I No Yes 

>4 days 7 days10 

1 In 1992, labeling provisions were put in place in Title 40 Code of Federal Regulations, part 156; in 1995, regulations w

implemented in Title 40, Code of Federal Regulations, Part 170 

2 Column 1 indicates increased (+), reduced (-) or no change (0) in protection (reentry and posting requirements) since 1

3 Pesticides with increased protections since 1995 are shaded, with the enhanced protection criteria in bold italic. 

4 Pesticides with reduced protection since 1995 are bolded, with the reduced protection criteria italicized. 

5 A single a.i. may be formulated as several products with different toxicity categories (i.e., II and III) 6 a.i. dermal/eye/skin toxicity category not specified on label. Category I is implied if dual notification is required by lab

category is assumed to be less than I (<I, i.e., II or III) 

7 Organophosphorous cholinesterase inhibitor 8 “Yes” for posting requirements pre-1995 was for Toxicity Category I products with an REI of 2 days or more when app

specified in 3 CCR 6776. Post-1995 posting requirements apply 1) when required by label, or 2) for all crops with REI

9 Indicates current reentry interval restrictions per 3 CCR 6772(b) 10 REI set by permit conditions 
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required posting for REIs of two days or more. Pre-WPS, oxamyl and phorate were required to 

be posted for REIs of two days or more; post-WPS, posting was no longer required following 

any application. The REI for cyfluthrin was reduced from 1 day to 1⁄2 day. Dimethoate and 

methomyl were identified as having both reduced and enhanced protections post-WPS: the 

minimum REI was increased, but posting was no longer required. For the 12 pesticides currently 

listed in Title 3, Division 6, California Code of Regulations (3 CCR) at Section 6772(b), 

restrictions post-WPS do not differ from pre-1995 restrictions (2). 

Analysis of the Impact of WPS on Pesticide-Related Illnesses and Attributes 

Methods WH&S’ Pesticide Illness Surveillance Program (PISP) maintains a database of 

pesticide-related illnesses and injuries. Medical reports are received from physicians and 

Workers’ Compensation records. Circumstances of exposure are investigated by the local county 

agricultural commissioner (CAC). The medical records and investigative findings are entered 

into an illness registry which provides an important resource for evaluating trends in pesticiderelated illness. The following definitions and restrictions apply for the PISP data used in 

analyses for this report (13,14): 

1. WH&S selected the years 1991 – 1999 for analyses. These data are examined for three 

discrete time periods: 

! four years’ data prior to the federal WPS (1991 – 1994), 

! two years’ data (1995 – 1996) during the transition period between implementation of the 

federal WPS and adoption of the federal WPS into California regulations. During this 

time period, the regulated community was subject to both federal WPS and pre-existing 

California worker protection regulations. 

! three years’ data (1997 – 1999) following adoption of the federal WPS into California’s 

worker protection regulations. 

2. Data were restricted to agricultural reentry workers exposed to field residues. 

3. A PISP case number is assigned for each person exposed to one or more pesticides. The 

terms “person”, “worker” and “case” are used interchangeably in this report. 

4. Cases were restricted to those having a “definite” or “probable" relationship to one or more 

pesticides. “Possible” cases were excluded because their tenuous relationship to pesticide 

exposure was unsuitable for rigorous cause-and-effect analyses. 

5. The basic unit of analysis was illness “episode”. An episode can involve a single case or 

multiple cases. 

The following questions drove the data analyses: 

1. Did the number or kind of illness episode change following WPS? 

2. Was there a change in illnesses related to the six pesticides noted as providing reduced 

protections post-WPS? 

3. Was there a change in illness occurrence related to any particular pesticides or crops? 

4. If changes were noted, were they related to the 13 crops for which California had short-term 

posting regulations pre-WPS? 

5. How many episodes were related to early entry violations? Why were fields entered early? 

6. Some cases are identified as meeting “priority criteria for human effects”, which involves 

one or more of the following: death, hospitalization for 24 hours or more with treatment 

rendered, or five or more symptomatic people seeking medical treatment (priority episodes) 

(15). These serious episodes warrant special attention to determine their causes. Did the 

nature, number or any other aspect of priority episodes change after WPS? 
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Results 

Analysis of Reduced-Protection Pesticides 

Table 1 identified six pesticides with reduced protections post-WPS: cyfluthrin, dimethoate, 

methidathion, methomyl, oxamyl, and phorate. The reduced protection under WPS for cyfluthrin 

was a decrease in REI from one day to 1⁄2 day. For the other five pesticides, those in toxicity 

category 1 pre-WPS, application to specific crops required posting for any REI > 2 days. After 

WPS, the posting requirement for methidathion and methomyl applied to all crops, but only for 

REIs > 7 days and dimethoate, oxamyl and phorate no longer required posting. We examined 

the PISP data for episodes involving these six pesticides, restricting analysis to episodes in which 

these pesticides were determined to be either the primary causal agent or one of several 

contributing pesticides. 

Table 2 summarizes data for episodes related to these six pesticides. Five episodes occurred 

pre-WPS and eight episodes occurred post-WPS. Altogether, 105 workers were affected. Seven 

of the 13 episodes involved reentry violations and seven were priority episodes. The small 

number of episodes involved precluded analysis by task. Methidathion and phorate were not 

involved in any episodes. Examination of the primary causes for reentry violations included one 

episode related to violation of posting regulations and three episodes each related to willful 

ignorance and lack of notification. For those episodes without reentry violations, contributory 

causes were unknown or related to either odor detection or allergy. The reductions in protection 

following WPS do not appear to have increased the hazard potential of these six pesticides. 

There was no increase in the number of episodes related to the WPS. 

Table 2. Summary of Illness Episodes 1991 – 1999 with a Definite or Probable Relationship to a 

Pesticide, and Determined to Involve Six Pesticides1

 with Reduced Protections Post-WPS as 

Causal or Contributory to the Illness 

 Number of Episodes per Interval Number of Priority Number of REI 

Active Ingredient 1991-1994 1995-1996 1997-1999 Episodes2

 Violations3

Cyfluthrin 0 0 34 2 0 

Dimethoate 1 1 1 0 3 

Methomyl 35

 1 25 4 4 

Oxamyl 1 0 0 1 0 

 Total 5 2 6 7 7 

1 No episodes related to methidathion or phorate were found 

2 Episodes meet “priority criteria for human effects”, which involves one or more of the 

following: death, hospitalization for 24 hours or more with treatment rendered, or five or 

more symptomatic people seeking medical treatment. 

3 Restricted entry interval 

4 Episodes related to reduction in pre-harvest interval from 150 days to day of harvest (1997) 

and were unrelated to WPS changes reducing the REI from 1 day to 1⁄2 day. Episodes 

occurred in 1997 with orange harvesters entering treated fields 3 – 11 days post-application. 

5 One episode with no reentry violations
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Post-WPS, cyfluthrin was identified as the causal agent in three illness episodes, which occurred 

between 3 and 11 days post-application; the REI is 12 hours. All three episodes occurred in 

Tulare County in 1997 and no episodes occurred pre-WPS. WH&S conducted two studies in 

1997 and determined that a recent change in product registration allowing cyfluthrin applications 

up to day of harvest, compared to a former pre-harvest interval of 150 days, was the most likely 

cause of the illness episodes (16,17). Cyfluthrin is currently under re-evaluation (18). 

Preliminary data suggest that exposures in the three illness episodes exceeded acceptable safe 

levels. 

Analysis of Frequency Rates and Task Distribution 

WPS establishes standards for an array of reentry situations by task. Specific criteria are set for 

field workers, irrigators, nursery workers, greenhouse workers and tractor drivers. Each PISP 

case was reviewed and categorized by task to evaluate related impacts. Table 3 presents 

summary statistics by task for PISP episodes, 1991 – 1999. These data are grouped into the three 

time periods described previously, of pre-WPS (1991 – 1994), the transition years between 

federal WPS and adoption of the WPS into California regulations (1995 – 1996), and full 

implementation of WPS into California regulations (1997 – 1999). Since the time periods differ 

in length, an annual frequency rate, the average number of episodes per year, is presented for 

overall comparison among intervals. 

Table 3. Summary by Task for Number of Pesticide Illness Surveillance Program Episodes (E) 

Definitely or Probably Related to Pesticides and Involving Agricultural Workers Exposed to 

Field Residues, 1991 – 1999, and Number of Persons (P) Involved in Each Episode 

Task 1991-1994 1995-1996 1997-1999 Totals 

 E P E P E P E P 

Fieldworker 22 63 11 111 22 158 55 332 

Greenhouse Worker 6 6 4 4 0 0 10 10 

Irrigator 13 18 9 13 4 7 26 38 

Nursery Worker 3 3 4 7 1 1 8 11 

Tractor Driver 5 5 1 2 1 1 7 8 

Grand Totals 49 95 29 137 28 167 106 399 

Avg. Episodes/Persons 

per Year 

12 24 15 69 9 56 12 44 

Overall annual episode frequency rates ranged from 9 – 15 per year. While 1997 – 1999 shows 

the lowest rate, a trend cannot be confirmed from these data. During all time periods, 

fieldworkers had more total illness episodes than did other work tasks and showed no trends. 

The number of episodes for all tasks other than fieldworker showed a steady decline over time. 

Overall, fieldworker episodes accounted for approximately 50% of all episodes and 80% of total 

ill persons exposed to field residues. Irrigators accounted for approximately 25% of all episodes 

and about 10% of all ill persons. Greenhouse workers, nursery workers and tractor drivers each 

comprised 6 - 10% of total episodes. As these tasks more typically involved a single individual, 

they accounted for only a few percent of the total number of ill persons and, combined, 

represented 7% of all ill persons. Since PISP data identified fieldworkers and irrigators as 
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having a greater potential for becoming ill compared to greenhouse workers, nursery workers 

and tractor drivers, these tasks received particular scrutiny in subsequent analyses. 

Analysis of Episode Frequency Rates by Crop 

To pinpoint potential deficiencies of WPS compared to California's prior regulations, nonreentry violation episodes were evaluated further. Table 4 displays, by work task, the crops 

associated with each non-reentry violation episode during the three time intervals pre-WPS 

(1991 – 1994), the transition years of 1995 – 1996, and following adoption of WPS into 

California regulations (1997 – 1999). 

Table 4. Definite and Probable Pesticide-Related Episodes Involving Agricultural Workers 

Exposed to Field Residues, with No Reentry Violations, by Crop and Task, 1991 - 1999 

(Number of Priority Episodes in Parentheses) 

Task Crop1 1991-1994 1995-1996 1997-1999 Total 

Fieldworker Apples 0 0 1 1 

 Cotton 0 0 1 (1) 1 (1) 

 Grapefruit 1 (1) 0 0 1 (1) 

Grapes2 8 (1) 6 (1) 9 (2) 23 (4) 

 Mushrooms 1 0 0 1 

 Oranges 1 (1) 0 33 (2) 4 (3) 

Peaches 0 1 0 1 

Plums 1 (1) 0 0 1 (1) 

 Sugarbeets 1 0 0 1 

 Tomatoes, 

 Processing 

0 0 1 (1) 1 (1) 

Greenhouse Worker Ornamentals 4 (1) 4 0 8 (1) 

Irrigators Cotton 2 0 0 2 

 Open Field 1 0 0 1 

Oranges 0 0 1 1 

 Spinach 0 0 1 (1) 1 (1) 

Nursery Worker Celery 0 0 1 1 

 Citrus4 0 2 (1) 0 2 (1) 

Ornamentals 2 1 0 3 

Tractor Driver Grapes 2 0 0 2 

Peaches 2 0 0 2 

 Tomatoes, 

 Processing 

1 0 0 1 

Total 26 (5) 13 (2) 17 (6) 59 (13) 

Avg. episodes per year 6.5 (1) 7 (1) 6 (2) 6 (1.5) 

1 Bolding indicates crop was one of the 13 with posting required pre-1995 for REIs 

of >2 days per 3 CCR Section 6776 

2 Grape episodes, by year, ranged from 2 – 5. No significant trend noted in examining the annual data 

by statistical process control. 

3 All episodes related to 1997 change in the pre-harvest interval for cyfluthrin 

4 Crop not specified
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Overall, the average annual illness frequency rate has remained constant across all nine years. 

Grapes are associated with the largest number of episodes, with 23 occurring in the 9-year 

period. The apparent 50% increase in episode frequency associated with grapes (8 episodes preWPS vs. 15 episodes during the transition years and post-WPS) was analyzed by a statistical 

process control program (SPC) (19). No significant trend was found. Annually, the number of 

grape illnesses was within historical variation, with between 2 and 5 episodes occurring each 

year. Oranges, grapefruit and unspecified citrus account for a total of eight episodes. Five were 

priority episodes, which involved a total of 85 persons. As discussed earlier in Analysis of 

Reduced-Protection Pesticides, the three post-WPS episodes in orange harvesters were related to 

cyfluthrin exposure, and were unrelated to WPS changes. Eight episodes were related to 

ornamental crops in greenhouses; none were priority episodes. No episodes were noted for 

tractor drivers after 1994. 

Analysis of Frequency Rates by Pesticide

For this analysis, the PISP illness data were restricted to episodes in which a specific pesticide 

was determined to be the primary causal agent. Sixty-four episodes, involving 24 pesticides, met 

this criteria. No pesticide-specific trends were noted pre- vs. post-WPS. Overall, from 

1991 – 1999, 13 pesticides were identified as causal in one episode each, 6 pesticides identified 

in two episodes each, two identified in 3 episodes each and one pesticide identified in four 

episodes. 

Only propargite (11 episodes, 5 pre-WPS and 6 post-WPS) and sulfur (18 episodes, 9 each preWPS and post-WPS) were associated with a significant number of episodes. Seven of these 29 

episodes were priority illness episodes which involved a total of 106 workers; the remaining 22 

episodes involved one worker each. WH&S has long recognized the potential hazard of these 

two pesticides and placed more stringent restrictions on their use than required by product 

labeling. WPS did not change the posting requirements for either propargite or sulfur, but the 

minimum label REI for sulfur was increased from less than one day to one day. California 

regulation already required a minimum one-day REI following sulfur applications. Additional 

sulfur and propargite use restrictions apply in California (3 CCR 6772) (2). WH&S continues to 

evaluate effective strategies to reduce illnesses related to propargite and sulfur. 

Analysis of Priority Episodes 

There were a number of episodes included in Table 3 which met priority criteria for human 

effects (priority episodes) (15). Summary data for the number of priority episodes and persons 

involved are provided in Table 5. Average annual frequency rates have remained stable over the 

nine years. 

The annual average number of persons involved in priority illness episodes quadrupled during 

1995 – 1996 (59 persons/year), compared to 1991 – 1994 (15 persons/year) and fell only slightly 

in 1997 – 1999 (50 persons/year). Unfortunately, while this increase is notable and disturbing, it 

is not amenable to further analysis, nor are there any obvious regulatory mitigations. The 

considerable number of workers who may be affected in a single priority episode underscores the 

need to continually examine potential solutions to prevent their occurrence. Table 6 provides a 

breakdown of priority episodes by task and indicates a similar frequency rate for each time 

period examined. 
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Table 5. Summary of the Distribution of Priority Episodes, 1991 – 1999 

Number of Episodes and Persons for Definite and Probable Pesticide-Related Episodes 

Involving Agricultural Workers Exposed to Field Residues 

Year Number of Episodes Number of Persons 

1991 3 12 

1992 6 18 

1993 2 6 

1994 2 26 

Sub-total 13 62 

Avg. per year 3 15 

 

1995 5 81 

1996 5 36 

Sub-total 10 117 

Avg. per year 5 59 

 

1997 7 96 

1998 3 39 

1999 2 16 

Sub-total 12 151 

Avg. per year 4 50 

 

Total 351

 330 

Avg. per year 4 37 

1 Includes 22 episodes with reentry violations and 13 episodes 

with no reentry violations. 

Table 6. Summary of the Number of Priority Episodes by Task, 1991 – 1999, for Definite and 

Probable Pesticide-Related Episodes Involving Agricultural Workers Exposed to Field Residues 

 Number of Episodes/Task Total 

Task 1991 – 1994 1995 - 1996 1997 - 1999 1991 - 1999 

Fieldworker 8 4 11 23 

Greenhouse Worker 1 0 0 1 

Irrigator 4 3 1 8 

Nursery worker 0 2 0 2 

Tractor Driver 0 1 0 1 

Total 13 10 12 35 

Average Frequency 

(per year, all tasks) 

3 5 4 4 
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Analysis of Reentry Violations and Probable Causes of Early Reentry 

WH&S analyzed the types and frequency of reentry violations/early entry restrictions violations 

pre- and post-WPS to determine why regulations were violated, and to evaluate any impacts 

WPS may have had on these underlying causes. Table 7 summarizes the overall episode 

statistics for reentry/early entry restriction violation status, by task, for the three time periods 

examined, 1991 - 1999. Overall violation frequency rates were similar among all time periods. 

The greatest variation in frequency rate over time was noted for fieldworker illnesses related to 

REI violations. The largest decrease was seen in the frequency rate for 1997 – 1999 irrigator 

illnesses related to REI/early entry restrictions violations. Overall, no discernable impacts were 

identified due to WPS. 

Table 7. Summary Statistics by Task for 106 Illness Episodes 1991 – 1999, for Definite and Probable 

Pesticide-Related Episodes Involving Agricultural Workers Exposed to Field Residues: Count of 

Reentry/Early Entry Restrictions Violations1

 (RV), Other Violations2 (Other), and No Violations3 (None) 

 1991 - 1994 1995 - 1996 1997 - 1999 

Task RV1

 Other2 None3 RV1 Other2 None3 RV1 Other2 None3 Total 

Fieldworker 9 1 12 4 0 7 7 3 12 55 

Greenhouse Worker 1 1 4 2 0 3 0 0 0 11 

Irrigator 9 0 3 9 0 0 2 1 1 25 

Nursery Worker 1 0 2 1 0 3 0 0 1 8 

Tractor Driver 0 0 5 1 0 0 1 0 0 7 

Total by Violation 20 2 26 17 0 13 10 4 14 106 

Avg. frequency per 

year, by violation 

5 0.5 6 8 0 7 3 1 5 12 

1 34 cases with restricted entry interval (REI) or early entry restrictions violations only; 13 

cases with multiple violations, including REI or early entry restrictions violations 

2 Non-REI/non-early entry restrictions violations which contributed to the episode 

3 No violations found or were non-REI/non-early entry restrictions violations and noncontributory to the episode 

Next, we reviewed all case investigations associated with each episode having REI violations to 

identify probable causes for early field reentry or non-compliance with early entry restrictions. 

All 47 episodes had a clear relationship to at least one underlying cause; two or more causes 

were noted for 31 of the 47 episodes (66% of episodes). Six categories of causes were identified; 

between one and four causes were associated with each episode. A count of 78 causes was noted 

overall for the 47 episodes. Table 8 displays these data, combined by cause category. The data 

in the shaded rows (substantial contact, exceeded 1 hour in field) show the specific early entry 

restriction violation within the broader PISP violation category of “Early Reentry”. They are 

included to evaluate compliance with WPS early entry restrictions which include prohibiting 

entry for at least 4 hours following pesticide applications, prohibiting hand labor tasks and 

substantial contact with treated foliage, requiring specified PPE, and limiting most early entry 

activities to one hour in 24 hours. 

When identified among multiple causes of reentry violations in an episode, posting violations 

were always considered the primary probable cause. This cause was noted in 8 of the 47 
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episodes (17%). The number of posting violations was insufficient for further analysis. Lack of 

notification was noted in 32 of the 47 episodes (68%) and was the most frequent probable cause 

of early entry violations both overall and within each time period. In these 32 episodes, lack of 

notification was noted as either secondary to posting violations or as the primary cause of reentry 

violations. Lack of notification was followed in frequency by “failure to wear required PPE”, 

which was associated with 26 of the 47 episodes (55%). This cause was noted as either the sole 

cause or when workers failed to wear required PPE due to lack of notification, posting violations 

and/or willful ignorance. Lack of hazard communication, while not a probable cause of early 

entry, was noted in 5 of the 47 episodes (11%) as secondary to either lack of notification (4 

episodes) or failure to wear PPE (1 episode). 

Overall, for the most recent time period, 1997 – 1999, it appears there is a decline in the number 

of episodes associated with both “lack of notification” and “failure to wear PPE”. However, 

WH&S is concerned about the number of episodes associated with these violations. Notification 

and hazard communication issues will be evaluated in subsequent WH&S analyses. Similarly, 

episodes noted as violating early entry restrictions for “substantial contact” or “exceeding 1 hour 

in field” should continue to be tracked to assess both their frequency and their potential impacts 

on fieldworker illnesses. 
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Table 8. Combined Totals for Probable Causes of 47 Illness Episodes with Reentry Violations, 

1991 – 1999, for Definite and Probable Pesticide-Related Episodes Involving Agricultural 

Workers Exposed to Field Residues 

 Number of Episodes 

Probable Cause1 1991 – 1994 1995 – 1996 1997 – 1999 

Lack of Notification 12 13 7 

Failure to Wear PPE2 9 12 5 

Posting Violation 2 4 2 

Willful Ignorance3 4 0 1 

Hazard Communication4

 2 3 0 

Sent Worker into Posted Field5 1 0 1 

Average Causes per Year 7.5 16 5.5 

Total Episodes with Reentry Violations 20 17 10 

Early Entry Restriction Violations6

Substantial Contact7 4 4 1 

Exceeded 1 hour in field8 not applicable 2 1 

1 Identified by author’s review of case investigations; data not available in PISP 

2 Failure to wear PPE violated either early entry restrictions or was secondary to 

notification, willful ignorance, and/or posting violations. 

3 Worker was aware of the regulations and/or restrictions, but chose to ignore them. 

4 Not a probable cause; noted secondary to lack of notification or failure to wear PPE 

5 Employer was aware of treated field and restrictions and ordered worker to 

enter the field in violation of FAC section 12984 (20). 

6 Shaded rows not included in cause counts but were noted as causes for over-exposure 

subsequent to reentry violation. 

7 Violations of any of the early entry restrictions, which include waiting at least 4 hours 

after a pesticide application, prohibition of hand labor activities and other substantial 

contact with treated surfaces, requiring specified PPE, and limit most early entry 

activities to one hour in 24 hours. This cause was noted in 5 irrigator episodes, 3 

fieldworker episodes and 1 tractor driver episode. 

8 All workers were performing early entry irrigation tasks. 

Table 9 summarizes the compliance (Violation Notice (VN); infraction documentation) and 

enforcement actions (Agricultural Civil Penalties (ACPs); fines) taken in response to illness 

episodes associated with reentry violations, 1991 – 1999, including priority episodes (15, 21). 

Overall, there was a slight increase in the rate that county agricultural commissioners (CACs) 

took such actions. 

In particular, the rate that ACPs were proposed in response to episodes has risen steadily over the 

nine-year period, from 20% in 1991 – 1994, to 53% during 1995 – 1996, to 70% in 1997 - 1999. 

During this time, DPR and the CACs have worked together closely to improve communication 

and program coordination. These data signal that the CACs and DPR have been increasingly 

successful in fulfilling key health and safety components of their enforcement programs. 
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However, efforts to deal vigorously and consistently with those responsible for reentry violations 

associated with documented illness can be improved. Overall, from 1991 – 1999, VNs were 

issued more frequently than were ACPs, with a total of 20 ACPs issued for the 47 illness 

episodes (43%). Illnesses associated with reentry violations demonstrate the serious human 

health consequences of pesticide over-exposure. Under the Enforcement Guidelines established 

late in 1994, such illnesses are considered grave violations of the worker safety regulations and 

those responsible face an automatic penalty (22). The Enforcement Guidelines’ effectiveness is 

demonstrated by the increased frequency of enforcement actions taken in response to illnesses 

related to REI violations. This analysis focused only on those episodes with the highest 

assurance that the illness was associated with pesticide exposure. That ACPs are not consistently 

proposed for all such violations indicates that DPR must continue their efforts to implement key 

health and safety components of its enforcement program. 

Table 9. Number of Compliance and Enforcement Actions Taken in Response to 47 Illness 

Episodes with Reentry Violations Which Involved Agricultural Workers Exposed to Field 

Residues, 1991 – 1999, and (Number of Priority Episodes) 

Number of Compliance/Enforcement Actions1

Compliance/Enforcement Actions Taken 1991 – 1994 1995 - 1996 1997 - 1999 

Agricultural Civil Penalty (ACP) 4 (2) 9 (4) 7 (4) 

Violation Notice (VN) 15 (5) 8 (4) 4 (2) 

Total Actions Taken 19 17 11 

Unknown Action Taken 

 (records unavailable) 

1 (0) 0 0 

No Action Taken 0 2 (1) 1 (0) 

Total episodes with reentry violations 20 17 10 

Rate of enforcement actions taken per total 

episodes in each time period (%) 

20% 53% 70% 

1 Compliance Action = Violation Notice (VN); Enforcement Action = Agricultural 

Civil Penalty (ACP). Some episodes resulted in both VN(s) and ACP(s). 

Summary of Meetings and Workshops with Farmworker Advocate Organizations, CACs, 

California Legislature, Representatives of the Agricultural Production Community and US EPA 

In 1999, Californians for Pesticide Reform issued a report (“Fields of Poison”) critical of DPR 

and CAC pesticide enforcement (23). In response, DPR met with many worker advocate 

organizations in July 1999 to discuss pesticide enforcement and safety-related issues which 

impact farmworkers (5). The farmworker advocates identified several worker health and safety 

program improvements for DPR to consider. DPR agreed to focus its efforts on the review of 

posting, notification, and hazard communication requirements. At a subsequent meeting in 

November 1999, the advocate organizations provided DPR with recommended modifications to 

these requirements. In February and March 2000, DPR attended five regional CAC meetings to 

discuss the farmworker advocate recommendations and obtain input. A summary of the CAC 

comments was shared at the May 2000, California Agricultural Commissioners and Sealers 
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association (CACASA) conference. Summaries of worker advocate and CAC comments are 

provided below. 

In February 2000, Senate Bill 1523 (Figueroa), sponsored by farmworker advocates, was 

introduced. The bill proposed changes to the field posting requirements. DPR staff conducted 

several queries of pesticide-related illness data for grower and farmworker advocate 

organizations. DPR and CACs coordinated a field tour for persons interested in the posting bill. 

CACs testified at the hearing. The bill was later defeated. 

In December 2000, at the request of the Assembly Agriculture Committee, DPR met with 

Senator Figueroa’s staff to discuss field posting regulations and legislation (6). DPR agreed to 

evaluate the field posting regulations to determine if these requirements were adequate. 

Notification and hazard communication requirements will be evaluated at a later date. 

In October 2000, DPR met with agricultural groups and CAC representatives regarding possible 

changes to the field posting, notification, and hazard communication requirements. Participants 

recommended that DPR hold meetings in several areas of the state to obtain input from 

agricultural production stakeholders. WH&S and CACs held two workshops with members of 

the agricultural production community in February 2001. Meetings were held in Monterey and 

Fresno counties to learn more about their systems for complying with WPS field posting, 

notification, and hazard communication requirements and to solicit their recommendations for 

improvements. A diverse group of about 25 participants attended each workshop, representing 

growers, pest control businesses, labor contractors, packer/shippers, and pest control advisors. 

The US EPA began a national assessment of the WPS program in 2000. DPR attended the first 

workshop in June and a second workshop in December. In February 2001, the WH&S 

assessment of the worker protection program was incorporated by amendment into the US 

EPA/DPR Federal Work Plan as the Pesticide Illness Surveillance Program (PISP) Data Analysis 

Project (7). Findings from the WH&S assessment will be shared with the US EPA Office of 

Pesticide Program representatives working on the national assessment. 

Summary of Recommendations on Posting Requirements from Farmworker Advocate 

Organizations 

1. Field posting should be required for all pesticide applications and REIs of any length. 

2. Increase the number of inspectors assigned to enforce compliance with field posting 

requirements. 

3. Instead of the current system consisting of different signs for short-term vs. long-term 

posting, there should be a single standardized posting sign for all applications to include the 

skull and crossbones, “DANGER/PELIGRO”, the date of application, the expiration of the 

REI, the name and phone number of the applicator, and specific health hazards. 

4. Growers should ensure signs are visible and properly posted. 

5. The sign should be easy to read from a distance and be at least 11⁄2 feet by 2 feet in size. 

6. Signs should be posted every 30 feet instead of the current requirement for every 

600 feet. 

7. There should be mandatory fines for all posting violations. 

8. Farm operators should be held responsible for any violations because they have overall 

control over all work conducted on the property they manage. 
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9. Signs should be removed immediately when the REI is over instead within the current three 

days permitted. 

Summary of CAC Response (in italics) to Farmworker Advocate Organizations’ 

Recommendations on Posting Requirements 

1. Field posting should be required for all pesticide applications and REIs of any length. 

! The benefit of increasing the workload so dramatically is not clear. DPR should analyze 

illness and compliance data related to posting violations and distribute their findings to 

the counties. If a problem currently exists, it must be fully documented. Without 

information on problems or trends, modifications are not justified. 

! Cost/benefit analysis should be conducted prior to implementing additional requirements. 

! Universal posting would dilute the current warning system for a true, immediate hazard, 

to merely an informational sign for hazard communication. (Similar to the ubiquitous 

warnings mandated by Proposition 65). 

! Mistakes that currently happen based on incorrect information would not be prevented. 

! Agricultural production takes place in open, unfenced and unattended rural areas. 

Posting each field with application history would be very vulnerable to vandalism, and 

difficult to establish and monitor. 

! Require posting for all crops which are high-intensity hand labor (peaches, grapes, vine 

seed, etc.) and for crops in which a high number of illnesses occur. 

2. Increase the number of inspectors assigned to enforce compliance with field posting 

requirements. 

Increasing resources for enforcement would help. The prioritization plan should address the 

priority of posting enforcement. 

3. Instead of the current system consisting of different signs for short-term vs. long-term 

posting, there should be a single standardized posting sign for all applications to include the 

skull and crossbones, “DANGER/PELIGRO”, the date of application, the expiration of the 

REI, the name and phone number of the applicator, and specific health hazards. 

This information, except for specific health hazards, might be a good idea. Listing specific 

health hazards should not be necessary since posting is intended to prevent entry and there 

should be no health hazards following expiration of the REI. 

4. Growers should ensure signs are visible and properly posted. 

5. The sign should be easy to read from a distance and be at least 11⁄2 feet by 2 feet in size. 

! Current regulations require readability. 

6. Signs should be posted every 30 feet instead of the current requirement for every 

600 feet. 

! Increasing the frequency of signs to less than 600 feet will dilute the impact as warnings. 

! Current requirement is sufficient to meet the intent to provide a warning to anyone who 

might enter. 

7. There should be mandatory fines for all posting violations. 

! Mandatory fines would create an adversarial atmosphere where education and 

cooperation could fail. 
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8. Farm operators should be held responsible for any violations because they have overall 

control over all work conducted on the property they manage. 

! Farm operators currently share employer responsibility with the farm labor contractor if 

they perform any employer functions such as providing supervision or instruction. 

9. Signs should be removed immediately when the REI is over instead within the current three 

days permitted (2). 

! It should be a serious violation (fine of $401 – $1,000) if posting signs are not removed 

within three days after expiration of the REI as required by regulation. 

Summary of Comments from DPR Workshops with Agricultural Production Stakeholders 

Early in 2001, WH&S and CACs held two workshops with members of the agricultural 

production community in Monterey and Fresno counties to learn more about their systems for 

complying with posting requirements, and to solicit their recommendations for improving these 

requirements. These counties were selected because they are foremost among agricultural 

production regions in the state and because they differ widely in both their cropping patterns and 

their posting regulations. Fresno County, in the middle of California’s Central Valley, grows 

alfalfa, cotton, citrus, and orchard, vine, and row crops. Generally, fields are large, rarely 

smaller than 20 acres, and can range from several hundred to over a thousand acres in size. 

Fresno County does not have posting regulations separate from those mandated in state 

regulations. Monterey County is coastal, the climate is cool and moist and crops can be grown 

nearly year-round. Monterey grows cole crops, lettuce, artichokes, strawberries, greenhouse 

crops, carrots, and celery. Fields are typically smaller than in Fresno County and may be only 

five to twenty acres in size. Often, small adjacent plots are owned by different growers, rather 

than large contiguous fields being operated by one grower, as is the pattern in Fresno County. In 

Monterey County, the close proximity of different crops, each requiring diverse pest control and 

cultivation techniques, contributed to a series of fieldworker illnesses in the late 1970s and early 

1980s. In response to these episodes, Monterey County developed its own “24-hour posting” 

regulation in 1983, which is more stringent than that required by state regulation (24). In 

Monterey County, posting prohibiting field entry is required for all pesticide applications (except 

for sulfur) to crop foliage that have an REI of 24 hours or longer. This regulation was successful 

in drastically reducing the occurrence of pesticide-related illnesses in Monterey County. 

WH&S wanted to hear from both of these regions in order to fully understand how the field 

posting systems were working throughout the state. A diverse group of about 25 participants 

attended each workshop, representing growers, pest control businesses, labor contractors, 

packer/shippers, and pest control advisors. Discussion focused on field posting, notification and 

hazard communication regulations. This report focuses only on the discussion of field posting 

requirements. 

Posting: All participants strongly believe that field posting prevents workers from early reentry. 

Monterey County participants support their 24-hour posting regulations, even though compliance 

is costly, because field posting prevents both application and reentry errors. 

Participants’ Problems Complying with Posting Requirements (primarily from Fresno County) 

! Warning signs are not durable and do not withstand weather, irrigation, and use around 

farming equipment. 
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! It is difficult to identify posted sub-plots within a field (e.g., lettuce varieties). 

! Signs are not always delivered with the pesticide product. 

! Every 600 feet is too frequent; too many warning signs dilute the message. 

! While warning signs work, they are time-consuming and costly to put up and remove. 

! Application re-scheduling and communication delays and breakdowns can lead to fields not 

being properly posted and fields being entered early. 

! Requiring posting for sulfur applications would result in grapes being permanently posted, 

diluting the intended warning. 

Participants’ Suggested Improvements to Posting Requirements 

! Require signs be plastic or metal. 

! Require signs be delivered with the product. 

! Reduce the number of warning signs to field corners and entry points only or one central 

location per field. Workers are already trained to look for the signs. 

! Make applicators, not growers, responsible for posting signs. 

WH&S Recommendations 

Issue 1: Identify and evaluate the impact of any reduced-protection pesticides post-WPS.

Findings: Six pesticides were identified, no impacts were found. 

Recommendation: No change is needed.

WPS enhanced minimum notification requirements for all pesticides by mandating oral or posted 

notification of all applications for all workers anticipated to walk within one-quarter mile of the 

treated field. For the majority of pesticides, protections were enhanced due to longer REIs or 

expanded field posting requirements. However, WH&S evaluation of the WPS regulations 

identified six pesticides (cyfluthrin, dimethoate, methidathion, methomyl, oxamyl, and phorate) 

as having potentially reduced protections compared to California's pre-1995 short-term posting 

regulations. WPS either eliminated the posting requirement, increased the time interval which 

triggers posting (i.e., from 2 days to more than 7 days), or reduced the REI for the six pesticides. 

Analysis of PISP illness episode data did not demonstrate increased hazard for these six 

pesticides resulting from WPS-related regulation changes. 

Issue 2: Evaluate and identify trends in PISP data which indicate WPS-related effects on illness 

frequency rate. 

Findings: No impacts were found.

Recommendation: No change is needed.

Illness frequency rates were similar pre- vs. post-WPS: episodes were similar in number and by 

task, crop and pesticide, priority episodes occurred within historical frequency and were 

distributed similarly to overall frequency rates, and violations occurred with similar frequency. 

While no WPS-related impacts were found, irrigators appeared to stand out over all three time 

periods as having a greater potential for illness. Irrigators accounted for 25% of all episodes and 

a similar percentage of all priority episodes, with a decline noted only during 1997 – 1999 for 

episodes related to REI violations. WH&S should conduct studies and/or further data analyses to 

evaluate irrigator exposure and activities. 
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Issue 3: Identify the probable causes of reentry violations; propose appropriate mitigations.

Findings: Multiple causes for early reentry/early entry restriction violations applied in 66% of 

episodes (31 of 47 episodes). Lack of notification (68% of episodes) and failure to wear 

required PPE (55% of episodes) were identified as the most frequent causes. Posting violations 

occurred in 17% of the episodes. Hazard communication violations occurred in 11% of the 

episodes but always secondary to either notification, PPE, posting or willful ignorance. 

Recommendations 

! No regulatory change is needed at this time. No WPS-related changes were noted in 

frequency rate for posting violations or other types of reentry violations. The frequency of 

posting violations accounts for a small, stable percentage of the probable causes of illnesses 

related to reentry violations (17%). The number of cases was too small for further analysis (a 

total of 8 episodes or an average of 1 episode per year). Failure to wear required PPE and 

lack of notification were far more commonly associated with reentry violations (combined, 

they comprised 74% of all probable causes) and present a larger problem than do field 

posting violations. Recent data indicates that this situation may be improving. While overall 

frequency rates for illnesses related to reentry violations have remained stable, illness 

frequency rates related to lack of notification and failure to wear required PPE have declined. 

WH&S evaluation of reentry violations contributory to illness does not support DPR 

expanding posting requirements at this time. Recommendations may be proposed pending 

WH&S’ evaluation of notification and hazard communication requirements. 

! DPR should continue to provide guidance to ensure appropriate and consistent enforcement 

actions are taken. The CAC should continue the current trend to take enforcement action for 

reentry violations that result in illness. DPR and the CACs should evaluate existing 

Enforcement Guidelines for proposing penalties in response to re-entry violations, and 

identify and strengthen sections that do not currently provide the CAC with sufficient 

guidance (20). While the overall frequency rate for illnesses related to reentry violations has 

declined in the most recent time period evaluated (1997 – 1999), reentry violations still 

occur. Stricter enforcement of existing regulations and requirements is anticipated to reduce 

their occurrence and should be undertaken prior to adopting more restrictive regulations (2). 

! Subsequent to the above evaluation, DPR should review compliance and enforcement actions 

and assess impacts on illness frequency related to reentry violations. 

! DPR should evaluate current compliance with the requirement to remove posting signs 

within three days of the expiration of the REI. If low compliance is identified, DPR and the 

CACs should develop and implement plans to improve compliance. 

! DPR and CACs should conduct focused training sessions on the requirements for field 

posting and field reentry following pesticide applications. DPR should consider this option 

when making recommendations subsequent to conducting analysis of the notification and 

hazard communication components of the WPS and California programs. 

Issue 4: Evaluate expanding field posting to all pesticides and restricted entry intervals of any length 

as an improvement to the current field posting requirements. 

Findings: Data indicate that current posting requirements are effective in preventing workers 

from entering fields early. Violations are due to failure to post, not failure to obey the posted 

warning. Failure to post required warning signs was the probable cause of reentry violations in 

17% of 47 episodes occurring, on average, once per year. Lack of notification was the most 

frequent cause, identified in 68% of episodes with reentry violations and frequently contributed 

to failure to wear required PPE (a cause in 55% of episodes with reentry violations). 
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Recommendations 

! No regulatory change is needed at this time. While expanding posting requirements is a 

mitigation option, lack of notification was far more frequently identified as causing reentry 

violations which resulted in illness. Since improving the notification process may also 

reduce posting violations, a thorough evaluation of the notification requirements is needed 

before adopting this option. WH&S has begun its evaluation, which includes assessing 

where breakdowns in the notification process occur and which workers may be most affected. 

The evaluation will guide our recommendations for improving the notification requirements. 

! DPR should evaluate ways to increase enforcement of current posting requirements, including 

increasing resources for enforcement and addressing the priority of posting enforcement. 

Issue 5: Identify and evaluate problems in complying with posting requirements.

Findings: The agricultural community reports problems with sign availability, durability, labor 

costs, too frequent spacing, and difficulty in identifying treated sub-plots. Farmworker 

advocates support a single standardized field posting sign for all pesticide applications, 

immediate removal when the REI expires, and signs posted more frequently than every 600 feet. 

Recommendations 

! Data from this evaluation are inadequate to support expanding the information required on 

posting signs or to post signs closer than every 600 feet. This issue of expanding information 

on the sign will be addressed further in DPR’s evaluation of the hazard communication 

requirements. 

! DPR and CACs should evaluate ways to ensure that posting signs are durable and available 

and adopt the most appropriate strategies to enforce compliance with requirements. 

Potential means to accomplish this may include the following: 

• During inspections, focus on compliance with current regulations in 3 CCR, Section 

6776, which require signs remain readable and legible for the duration of the REI. 

• Evaluate whether adding the application date to the long-term posting signs would assist 

inspectors in assessing compliance with posting requirements. 

• Amend appropriate portions of 3 CCR, Section 6776, to require signs be either 

“durable” and/or “remain intact” throughout the posting interval. This would not 

preclude use of cardboard signs, provided they remained intact and legible. However, it 

may encourage greater availability and use of plastic and metal signs.

• Work with the agricultural community, industry, university and/or US EPA to develop 

durable, standardized posting systems, addressing components such as signs, supports 

and hardware. 

! DPR and CACs should provide guidance to the agricultural community on posting treated 

sub-plots, such as lettuce varieties, to clearly identify the treated area. Guidance may 

consist of an Enforcement Letter, outreach training, and/or other appropriate method. 

References 

1. Office of the Federal Register (1998) Title 40 Code of Federal Regulations (CFR), Parts 156 

to 1890. National Archives and Records Administration, U. S. Government Printing Office, 

Washington, D. C. 20402-9328 

2. California Department of Pesticide Regulation (1998) Title 3, Division 6, California Code of 

Regulations. California Department of Pesticide Regulation, 1001 I Street, Sacramento, 

California 95814 
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3. California Food and Agriculture Code, Office of Administrative Law. Available on the web 

at: www.oal.ca.gov (accessed June, 2001) 

4. California Department of Pesticide Regulation (1996) WPS Rulemaking File 

WHS-96-1127-05, Vol. 1. Registration Library, 1001 I Street, Sacramento, California 95814 

5. Katten, A. (1999) Letter dated Sept. 2, to Chuck Andrews, California Department of 

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Foundation, 2424 K Street, Sacramento, California 95826 

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Safety Branch, 1001 I Street, Sacramento, California 95814 

8. Maddy, K. T. (1986) Short-term Posting Regulation (HSM-86001). California Department of 

Pesticide Regulation, Worker Health and Safety Branch, 1001 I Street, Sacramento, 

California 95814. 

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http://www.cdpr.ca.gov/docs/label/labelque.htm; accessed January 19 – 25 

10. Crop Data Management Systems, Inc. (2001) Pesticide Labels Directory at website: 

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Ingredient Used. Pesticide Use Report query, January 24. California Department of Pesticide 

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13. Mehler, L. (2001) Pesticide Active Ingredients Named in Definite, Probable and Possible 

Field Residue Episodes, 1991-1998. Pesticide Illness Surveillance Program database query. 

California Department of Pesticide Regulation, Worker Health and Safety Branch, 1001 I 

Street, Sacramento, California, 95814 

14. Microsoft Corp. (1996) Microsoft Access Version SR-2. Redmond, Washington, 98052 

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Department of Pesticide Regulation, Pesticide Enforcement Branch, 1001 I Street, 

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California, 95814. This document is also available on the web at: 

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19. D. A. Martin Software, SPC Orchestra 7.1, Revision SR-1. P. O. Box 52848, Knoxville, 

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20. California Legislative Counsel (2001) California Food and Agricultural Code, Article 10.5, 

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Sacramento, California, 95814 

22. Pesticide Enforcement Branch and the California Agricultural Commissioners and Sealers 

Association Co-Agency Committee (1994) Enforcement Guidelines – A Uniform Approach 

to Pesticide Use Enforcement Activities. California Department of Pesticide Regulation, 

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23. Reeves, M., Schafer, K., Hallward, K., Katten, A. (1999) Fields of Poison, California 

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24. Monterey County Agricultural Commissioner. Monterey County Posting Regulation. 

Monterey County Agricultural Commissioner, 1428 Abbott Street, Salinas, California 93901