Human Exposure to naled mosquito control Human Exposure to naled mosquito control pesticides, Florida 2004pesticides, Florida 2004..

A. J. Becker, MPH, PhD 1, Z. Duprey, DVM, MPH 2, S.D.

Rivers, MS 1, G. Luber, MA, PhD 2, C. Blackmore, DVM, PhD 1, Carol Rubin, DVM, MPH 2. (1) Bureau of

Community Environmental Health, Florida Department of Health, 4052 Bald Cypress Way, Tallahassee, FL

32399. (2) National Center for Environmental Health, Centers for Disease Control and Prevention, MS F-46,

Atlanta, GA 30341

Hurricane season 2004Hurricane season 2004

Mosquito Average per trap by dateMosquito Average per trap by date

Mosquito Populations Over Time in St John's County, Florida

0

100

200

300

400

500

600

8/3/2004 8/9/2004 8/16/2004 8/23/2004 8/30/2004 9/13/2004 9/28/2004 10/5/2004 PosttreatmentDate

Avg

# pe

r tra

p

Cx nigripalpus

Ps columbiae

Trap total

Charley Frances

Florida’s Public Health Florida’s Public Health ResponseResponse

• Request aerial spraying with mosquito adulticide (naled)

• Invite CDC to assist in assessing human pesticide exposure

CHOLINERGIC FIBER

SprayingSpraying

Took place on the evening of October 4, 2004. Naled was applied at 2/3 an ounce per acre, covering approximately 228,000 acres of St. Johns County.

MethodsMethods

• Prospective study design – assessment of a baseline prior to

determining exposure

Post-Exposure Fate of a Nonpersistent Chemical in Post-Exposure Fate of a Nonpersistent Chemical in Blood and UrineBlood and Urine

Concentration vs timeConcentration vs time

Time (Days)

BloodToxicant/Metabolite

Urinary Metabolite

1 10 100 1000

Con

cent

ratio

n

MethodsMethods• Selection of Participants- Randomly chosen

census blocks from 5 proposed spray areas. • DOH/CDC Teams- Teams consisted of one FLDOH

and one CDC member and an attempt was made to have one male and one female per team. The teams were trained on how to recruit and complete questionnaires.

• Participants- Participants were required to meet the following criteria:

• - 18 years of age or older• - Able to speak English• - Able to give informed consent• - In the county during the spray event

Participant’s Participant’s Questionnaire and Questionnaire and Sample CollectionSample Collection

• Signed consent form

• Pre-spray questionnaire + urine specimen,

• Five post-spray collection cups and instructions on collecting, labeling and storing the samples

• Collections at 8 h increments (morning, noon and night).

• Teams returned two days post-spray to collect the samples and administer the post-questionnaire.

Verify exposure through Verify exposure through environmental samplingenvironmental sampling

• Not done

Pre-Exposure QuestionnairePre-Exposure Questionnaire• In the past 3 days…

– Handle or apply fertilizer

– Done farm field work, such as harvesting or weeding, worked in a packing or farm stand with raw fruits, vegetables, or flowers

– Worked in a nursery or greenhouse

– Worked in a cannery or food processing plant– Done lawn or other landscape maintenance

– Applied flea or tick shampoo, dips, powders, or flea collars on pets

– Eaten fresh fruit or vegetables– Experienced pesticide-poisoning like illness

Post-Exposure Post-Exposure QuestionnaireQuestionnaire

Added questions:• From the spray time to 12 hours post spray, how

many hours were you in the county?• Did you see or hear the spray plane?• Did you attempt to avoid contact with the

mosquito spray?– Close all windows– Turn the air conditioning to recirculate– Clean off all lawn furniture before using– Stay indoors for at least 1 hour after spraying– Clean off all children’s toys before they use them– Wash all garden vegetables before eating or serving

Dana Henehan, from CDC, aliquots the Dana Henehan, from CDC, aliquots the urine samples before shipping them to the urine samples before shipping them to the CDC/NCEH laboratory in Atlanta, GeorgiaCDC/NCEH laboratory in Atlanta, Georgia

AnalysisAnalysisOrganophosphate metabolites Organophosphate metabolites

• Gas chromatography/tandem mass spectrometry (GC/MSMS).

• Dimethylphosphate- Non-specific naled metabolite

• Other organophosphate metabolites tested in lab.

AnalysisAnalysis

• N > urine organophosphate metabolite levels post-spray

• N < decreases in urine metabolite levels post-spray

• Compare metabolite levels to household and workplace exposure questionnaires

• Compare metabolite levels to symptoms reported comparing pre and post samples

St John’s participation and completion ratesSt John’s participation and completion rates

• A total of 626 individuals were contacted by the 12 teams and 235 (37%) agreed to participate. Of those 235, 210 completed the study, an 89% study completion rate.

Age and gender demographics Age and gender demographics

• Age (n=204)

Mean: 50.19, Range 18-78

• Sex (n=205) Male: 92 (44.9%)

Female: 113 (55.1%)

Ethnicity Census 2000 vs. StudyEthnicity Census 2000 vs. Study

Ethnicity 2000 census data St. John’s study

White 90.92 % 88.3 %

African American 6.29 % 6.8 %

Hispanic/Latino 2.6 % 3.4%

Native American 0.26 % 1.0 %

Asian 0.95 % 0.5 %

Pacific Islander 0.05 % 0.0 %

Area participant's residenceArea participant's residence• N=203• Hastings: 42 (20.7%)• Jacksonville: 23 (11.3%)• Ponte Verda Beach: 11 (5.4%)• St. Augustine: 125 (61.6%)• Switzerland, FL: 2 (1.0%

Risk FactorsRisk Factors• Pre

• Eat Fruit & Veg- 72%• Lawn- 35.6% (73)• Handled-18.5% (38)• Flea- 7.8% (16)• Field Work- 3.4% (7)• Fruit Stand-0.5% (1)

• Post• Eat Fruit & Veg- 72%• Lawn- 20% (40)• Handled- 8.5% (17)• Flea- 3.5% (7)• Field Work- 2% (4)• Fruit Stand- 0.5% (1)

Post BehaviorsPost Behaviors• Saw plane- 45% (91)• Closed windows- 67% (136)• AC to recirculate- 58% (117)• Wiped lawn furniture- 4.5% (9)• Stayed indoors- 58% (117)• Wiped toys- 1.5% (3)

Symptoms Raw ResultsSymptoms Raw Results• Pre symptoms

• Headaches 18% (37)

• Dizziness 6% (12)

• Nausea 5% (10)

• Abdominal Pain 5% (10)

• Weakness 4% (9)

• Excess tearing 4% (9)

• Trembling hands 3% (6)

• Post symptoms• Headaches 13% (26)

• Nausea 5% (10)

• Abdominal Pain 4% (9)

• Dizziness 3% (7)

• Excess tearing 2% (4)

• Diarrhea 2% (4)

• Weakness 2% (4)

• Trembling hands 2% (3)

Evaluation of pre and post Evaluation of pre and post questionnaires for symptomsquestionnaires for symptoms

No pre questionnaire symptoms

Pre questionnaire symptoms

No post questionnaire symptoms

133 27

Post questionnaire symptoms

12 32

Symptoms reported by post Symptoms reported by post questionnaire onlyquestionnaire only

Diarrhea Head ache

Dizziness Throat irritation

Nausea Tearing

Total 3 10 2 1 3 1

Pesticide Exposure Reported to Pesticide Exposure Reported to Pesticide Exposure Surveillance Pesticide Exposure Surveillance

Program (PESP)Program (PESP)

• Two complaints

a. Small child waiting for the bus the next morning developing respiratory symptoms.

b. Skateboarders with irritation to the upper

respiratory tract, eyes stinging and skin burning (They reportedly observed the plane fly over).

Results-lab analysisResults-lab analysis

Time period*

Total n of samples

% with detectable

DMP

Median level of DMP (ug/L)

Baseline 229 67.25 3.14

Post-spray 1 123 47.97 <LOD

Post-spray 2 218 40.83 <LOD

Post-spray 3 223 41.70 <LOD

Post-spray 4 112 41.07 <LOD

Post-spray 5 149 32.89 <LOD

Post-spray 6 28 57.14 1.85

Behavior(Number

responses)

N Pre-

sprayn (%)

N Post-spray

n (%)

N Pre- and Post-spray

n (%)P-value

Handling pesticides (203)

37 (18.2) 17 (8.4) 6 (3.0) 0.06

Field/farm work(202)

7 (3.5) 4 (2.0) 3(1.5) <0.01

Produce stand work (203)

1 (0.5) 1 (0.5) 0 (0) 1.00

Lawn work(n=203)

72 (35.5) 40 (19.7) 27 (13.3) <0.01

Applying pet flea products (202)

16 (7.9) 7 (3.5) 3 (1.5) 0.01

Eating fresh produce (185)

136 (73.5)

133 (71.9) 116 (62.7) <0.01

Symptoms (Number of responses)

Symptoms, Pre-sprayn (%)

Symptoms, Post-sprayn (%)

Symptoms Pre- and Post-sprayn (%)

P-value

Nausea (196) 10 (5.1) 10 (5.1) 4 (2.0) <0.01

Vomiting(196)

3 (1.5) 2 (1.0) 1 (0.5) 0.03

Diarrhea(196)

3 (1.5) 4 (2.0) 1 (0.5) 0.06

Abdominal cramps (196)

10 (5.1) 9 (4.6) 5 (2.6) <0.01

Headache(199)

37 (18.6) 26 (13.0) 16 (8.0) <0.01

Trembling(197)

6 (3.0) 3 (1.5) 3 (1.5) <0.01

QuestionsQuestions