The Health of Farmworkers-Pt. 2

Marc Schenker M.D., M.P.H.• Dept. Public Health Sciences, University of California

at Davis

• Director, Western Center for Agricultural Health and Safety

Part II

****

Acute Injuries

and Fatalities

of Farmworkers

Outline

• The hazardous passage

• Occupational fatalities among agricultural workers

– Animal

– Machine/tractor

– Transportation

• Fatalities of children

• Pesticides

Causes of Death Among Latin Immigrants Crossing US Border

• During the crossing– Exposure– Drowning– Accidents– Murder

• After the crossing– Disease– Injury (occupational)

U.S.-Mexico Border: The Season of Death

“The deaths trickle in over the cooler months. A couple here from a rollover. Four dead there during a cold snap. They begin in

earnest once the temperature spikes over 100 degrees sometime in May.”

PBS Frontline, June 27, 2006

Occupational Fatalities

in

Agriculture

SOURCE: U.S. Bureau of Labor Statistics, U.S. Department of Labor, 2007

Occupational fatality rates by age group for farming, 1992-2004*

* Excludes New York City. Rates calculated by NIOSH and may differ from BLS.* Excludes New York City. Rates calculated by NIOSH and may differ from BLS.

Agriculture Fatality Rate vs. Private Sector, US, 1992 - 2002

Children : The Forgotten

Farmworkers

“Farmers and Labor

Contractors say they allow

children to perform field work

because the grower needs to

get the crop in, parents need

the money or children would

learn the value of working.”

Fresno Bee, 12/14/92

José (22) and Angelica Alatorre and son Guillermo. Jose

died while working in a manure pit at Aguiar-Faria & Sons

Dairy, Gustine, CA. February 22, 2001

Pesticide Toxicology

• Many toxin categories

• Affect various organs

• Varied health effects

Diagram illustrating various pesticide-related health effects.

Definition of Pesticide

“Any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any insects, rodents, nematodes, fungi, or weeds, or any other forms of life declared to be pests; any substance or mixture of substances intended for use as a plant regulator, defoliant, or desiccant.”--Federal Insecticide, Fungicide, and Rodenticide Act (US EPA, 1947)

US Pesticide Use

• 4.5 billion pounds chemicals per year– 890 active ingredients,

30,000 formulations– Uses

• 75% agricultural • 25% home, garden,

structural

Agricultural Pesticide Use

• High volume:– Hand labor (Western states)

• Vineyards• Orchard, row vegetables, nursery

• Low volume: – Mechanized (Midwest states)

• Livestock insecticide dipping• Grain agriculture

Pesticide Exposure:Occupational Settings

• Multiple industries – Agriculture– Emergency response– Maintenance– Transportation

• Variety of workers– Applicators, fieldworkers– Firefighters – Medical personnel– Flight attendants

NEETF 2002

Pesticide Exposure: Environmental-Occupational Interface

• Drift

– Off-target physical movement of pesticide through air

• Take-home – Contaminated clothing– Pesticide containers brought

home

Pesticide Exposure:Environmental Settings

• Use in schools

• Lawn, garden use

• Household cleaning

• Home pesticide use

• Residues in food

Pesticide Exposure: Accidental Ingestion

• Improper storage or mislabeling of containers

• Prescription pesticides resembling oral medications

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Pesticide Exposure: Suicide/Homicide

San Francisco Chronicle Monday, January 17, 2000

Coroner Identifies Man Who Swallowed Pesticide

• Unknown substance

• Secondary exposure

Unintentional Pesticide Illness, USA Toxic Exposure Surveillance System 1993-1996

1

10

100

1000

10000

100000

MinorModerate

MajorFatal

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Illness severity

Pesticide Illness Rates Vary by Occupation

Source: HS-1688, Cal EPA

Organophosphate pesticide poisoning rates by agricultural sector California, 1982--1990

Pesticide Illness Around the World

CostaRica

SriLanka

Sweden U.K.U.S.A.

Fatalities

Hospitalizations0

200

400

600

800

1000

Annual rates of intentional and unintentional pesticide-related fatalities and hospitalizations in several countries

US EPA Toxicity Classification(Systemic toxicity, eye irritation, skin irritation)

• Class I: “Danger” – Fatal if ingested; corneal opacity; corrosive to skin

• Class II: “Warning”– May be fatal if ingested; reversible corneal opacity; severe

skin irritation• Class III: “Caution”

– Harmful if ingested; no corneal opacity; moderate skin irritation

• Class IV: “Caution”– May be harmful if ingested; no eye irritation; mild/no skin

irritation

Common Components of Pesticide Formulations

• Technical grade chemical (active ingredient)

• Adjuvants/synergists

• “Inert” ingredients– e.g., formaldehyde, sulfuric acid,

benzene, toluene, other organic solvents

Diagnosis of Pesticide Illness• Exposure history most important

– Occupational and environmental history– Duration, dose, route of potential exposure

• Symptom review• Physical exam & lab findings • Health effects may be due to any component of

pesticide formulations

41

Commonly-used Acronyms for Cholinesterase Inhibition Syndromes

• Salivation

• Lacrimation

• Urination

• Diarrhea

• Diarrhea

• Urination

• Miosis

• Bronchorrhea

• Emesis

• Lacrimation

• Salivation

42

Cholinesterase Inhibitors Clinical Presentations Vary

• Some signs & symptoms may be absent– Bronchorrhea more likely with high-dose

exposures (ingestion)• Common presentations

– Nausea, vomiting– Miosis – Sweating, urinary frequency

– Non-specific constitutional symptoms

Aspects of History that Suggest Pesticide Illness

• Multiple cases– Similar symptoms, exposure history

• History of chemical application– Home or office

• Accidental ingestion, esp. children• Suicide, homicide attempts

Pesticide Illness Nonspecific Symptoms & Signs

• Rash • Flu-like symptoms

– Dizziness, malaise, respiratory tract irritation• Gastrointestinal symptoms• Seizures• Odor-related effects

– Not toxicological effects of active ingredient

Pesticide Illness May Mimic Common Medical Conditions

• Mild:

– Upper respiratory tract infection/influenza– Food-borne illness– Asthma – Plant-induced irritant or allergic dermatitis

• Severe:

– Cerebrovascular accident– Psychiatric dysfunction – Heat stroke

• Application records• Label • Material Safety Data Sheet

• www.msdsonline.com• http://www.ilpi.com/msds/index.html

How to Identify Pesticides

Sources of Pesticide Information• Internet

– EXTOXNET: http://ace.orst.edu/info/extoxnet/– California Department of Pesticide Regulation:

http://www.cdpr.ca.gov/docs/label/labelque.htm– Pesticide Action Network: http://www/pesticideinfo.org/index.html

• Textbooks– US EPA. Recognition and Management of Pesticide Poisonings. 1999; 5th ed.

http://www.epa.gov/pesticides/safety/healthcare– R Krieger (ed). Handbook of Pesticide Toxicology. 2001; 2nd ed.

• Poison Control Centers: 1-800-222-1222

• National Pesticide Information Center (NPIC): 1-800-858-7378 or npic@ace.orst.edu

Treatment of Pesticide IllnessDecontamination

• Shower, shampoo

– Scrub under fingernails

• Contain contaminated clothing, body fluids

– Save for residue analysis

• Protect treating staff

– Body fluid precautions

– Personal protective equipment if appropriate

• Symptomatic treatment– Respiratory distress

• Maintain airway, breathing, circulation• Oxygen, bronchodilators if indicated

– Ingestion• Gastric lavage, charcoal if indicated

• Specific antidotes where applicable

Pesticide IllnessMedical Treatment

Poison Control Centers

• Toxicity

• Decontamination

• Management

• Reporting

Case

Applicator with Gastrointestinal Illness

• 27 year-old pesticide applicator with dizziness, headache, body ache, nausea and vomiting. Sprayed Carzol yesterday.

• Exam: Weak (not flaccid), oriented; orthostatic hypotension; exam otherwise normal.

• Cholinesterase normal compared to laboratory reference range

Applicator with Gastrointestinal Illness

Discussion

• Differential etiology of gastroenteritis• Pesticide-related• Food-borne• Viral

• Test results confirm clinical suspicions– Normal results do not rule out exposure– Treatment based on symptoms

53

• 66 year-old male with eye irritation, abdominal pain, nausea, vomiting, headache, dizziness, frequent urination, muscle shaking. Symptoms began after weeding a cotton field for 4 hours.

• Occasional palpitations but no other symptoms over the past 6 months

• 33 other crew members complain of similar symptoms

Case

Farmworker with Multiple Symptoms

54

Farmworker with Multiple Symptoms

Exposure History• 4:00 am: Aerial application of

– Carbofuran (N-methyl carbamate)

– Abamectin (macrolytic lactone)

– Mepiquat chloride (growth regulator)

• 6:00 am: Workers entered field

• 10:00 am: Symptoms

55

Farmworker with Multiple Symptoms

Physical Exam

• Nausea & abdominal pain

• Conjunctival injection

• Irregularly irregular pulse; rate 106-155,

• Lungs clear, no murmurs; neurological exam normal

This warning sign was posted after the workers entered

the field and became ill.

56

Pyrethroid Insecticides

• Use increasing• Examples of use

– Structural & agricultural– Pet flea control– Pediculicide

• Vector control– West Nile virus– Aircraft “disinsection”

Source: CDC

57

Pyrethroids: Health Effects Skin

Paresthesia, dermatitis Respiratory

Rhinitis Systemic

Dizziness, headache Fasciculations, seizures, Hormonal disruption in vitro

58

Pyrethrin & Pyrethroid Illness: Treatment

• Decontamination• Vitamin E cream • Symptomatic therapy • Remove from further

exposure if needed

59

Case

Woman Exposed to Flea Bomb• 35 year-old non-pregnant female with skin burning,

itching and chest tightness after putting on clothes from closet.

• Physical exam

– Arms and face bright red

– Vital signs normal

– Lungs clear

60

Woman Exposed to Flea Bomb

Ingredients

• Label– 0.435% permethrin – 0.05% pyrethrins – 0.4% piperonyl butoxide– 99.115% inert ingredients

• Recommended no entry for 4 hours after fogging

61

Fumigants

• Halogenated hydrocarbons– Methyl bromide– Ethylene dibromide, DBCP

• Inorganic compounds– Sulfuryl fluoride

• Pro-fumigants – Metam sodium

• Metal phosphides– Aluminum, Zinc, Magnesium

US

DO

T

62

Fumigants Methyl Bromide

• High vapor pressure• Heavier than air• Odorless

– Chloropicrin added• Toxic mechanism

– Tissue methylation

C

H

H

Br H

Pesticide Availability in Mexico

Pesticide Illness: Summary

• Occupational, environmental history

• Clinical suspicion

• Tests supplement clinical diagnosis

• Treatment symptomatic, few exceptions

Thank you!