Pesticide-Induced Diseases: Asthma/Respiratory Effects

Since the mid-1980s, asthma rates in the U.S. have skyrocketed to epidemic levels, particularly in young children. In the U.S. alone, around 16 million people suffer from asthma. Asthma is a serious chronic disorder, and in some cases life-threatening disease, of the lungs characterized by recurrent attacks of bronchial constriction, which cause breathlessness, wheezing, and coughing. Researchers have found that pesticide exposure can induce a poisoning effect linked to asthma.

Low-income populations, people of color, and children living in inner cities experience disproportionately high morbidity and mortality due to asthma. According to the National Institutes of Health’s National Institute of Allergy and Infectious Disease, African Americans are four to six times more likely than whites to die from asthma. Therefore, any time our policies allow regulators to permit uses of pesticides with known asthma effects, which is done daily, a disproportionate impact is felt in the African-American community. Among other policies, this toxics policy contributes to a cycle of poverty, as asthma is the leading cause of school absenteeism due to chronic illness. Learn more about pesticides and asthma.

• Pesticides and asthma
  This article reviews the mechanistic evidence lending support to the concept that either acute or chronic low-level inhalation of pesticides may trigger asthma attacks, exacerbate asthma or increase the risk of developing asthma. Many pesticides are sensitizers or irritants capable of directly damaging the bronchial mucosa, thus making the airway very sensitive to allergens or other stimuli. However, most pesticides are weakly immunogenic so that their potential to sensitize airways in exposed populations is limited. Pesticides may increase the risk of developing asthma, exacerbate a previous asthmatic condition or even trigger asthma attacks by increasing bronchial hyper-responsiveness.
  [Hernández, AF., Parrón, T. and Alarcón, R. 2011. Curr Opin Allergy Clin Immunol.11(2):90-6]
• Rhinitis associated with pesticide exposure among commercial pesticide applicators in the Agricultural Health Study
  To investigate the association between current rhinitis and pesticide use, authors used data from 2245 Iowa commercial pesticide applicators in the Agricultural Health Study. 74% of commercial pesticide applicators reported at least one episode of rhinitis in the past year (current rhinitis). Five pesticides used in the past year were significantly positively associated with current rhinitis: the herbicides 2,4-D, glyphosate and petroleum oil, the insecticide diazinon and the fungicide benomyl. The association for 2,4-D and glyphosate was limited to individuals who used both in the past year (OR 1.42, 95% CI 1.14 to 1.77). Both petroleum oil and diazinon showed consistent evidence of an association with rhinitis, based on both current use and exposure–response models.
  [R E Slager, J A Poole, T D LeVan, et al. 2009. Occup Environ Med 2009 66: 718-724]
• Gene-Environment Interactions and Airway Disease in Children
  Asthma is the most common chronic disease of childhood in the United States, affecting nearly 6.5 million children. The prevalence and severity of childhood asthma have continued to increase over the past 2 decades, despite major advances in the recognition and treatment of this condition. Representing a heterogeneous collection of airway diseases, asthma has multiple pathologic processes resulting from the interactions of genetic susceptibility and environmental exposures. Preventing and treating airway disease in children will require new research approaches to understanding these complex interactions.
  [Schwartz, D. 2009. Pediatrics.123, Supplement 3:S151 -S159]
• Pesticides and Atopic and Nonatopic Asthma among Farm Women in the Agricultural Health Study
  Studying 25,814 farm women in the Agricultural Health Study, authors used self-reported history of doctor-diagnosed asthma with or without eczema and/or hay fever to create two case groups: patients with atopic asthma and those with nonatopic asthma. Growing up on a farm (61% of all farm women) was protective for atopic asthma and, to a lesser extent, for nonatopic asthma. Pesticide use was almost exclusively associated with atopic asthma. Any use of pesticides on the farm was associated only with atopic asthma. This association with pesticides was strongest among women who had grown up on a farm. Women who grew up on farms and did not apply pesticides had the lowest overall risk of atopic asthma compared with women who neither grew up on farms nor applied pesticides. A total of 7 of 16 insecticides, 2 of 11 herbicides, and 1 of 4 fungicides were significantly associated with atopic asthma; only permethrin use on crops was associated with nonatopic asthma.
  [Hoppin, J.et al. 2008. American Journal of Respiratory and Critical Care Medicine Vol 177. pp. 11-18]
• Early exposure to dichlorodiphenyldichloroethylene, breastfeeding and asthma at age six
• Summary health statistics for U.S. children: National Health Interview Survey, 2003.
  This report presents both age-adjusted and unadjusted statistics from the 2003 National Health Interview Survey (NHIS) on selected health measures for children under 18 years of age, classified by sex, age, race, Hispanic origin, family structure, parent's education, family income, poverty status, health insurance coverage, place of residence, region, and current health status. The topics covered are asthma, allergies, learning disability, Attention Deficit Hyperactivity Disorder (ADHD), use of prescription medication, respondent-assessed health status, school-loss days, usual place of health care, time since last contact with a health care professional, unmet dental needs, time since last dental contact, and selected measures of health care access. In 2003, most U.S. children under 18 years of age had excellent or very good health (83%). However, 10% of children had no health insurance coverage, and 5% of children had no usual place of health care. Thirteen percent of children had ever been diagnosed with asthma. An estimated 8% of children 3-17 years of age had a learning disability, and an estimated 6% of children had ADHD.
  [Centers for Disease Control and Prevention. 2005. Vital and Health Statistics 10 (223)]
• Asthma's Impact on Children and Adolescents
  Low-income populations, minorities, and children living in inner cities experience disproportionately high morbidity and mortality due to asthma.
  [Centers for Disease Control and Prevention, National Center for Environmental Health. 2005]
• Asthma Prevalence and Control Characteristics by Race/Ethnicity - United States, 2002
  To assess asthma prevalence and asthma-control characteristics among racial/ethnic populations, CDC analyzed 2002 data from the Behavioral Risk Factor Surveillance System (BRFSS). This report summarizes the results of that analysis, which indicated that among the estimated 16 million (7.5%) U.S. adults with asthma, self-reported current asthma prevalence among racial/ethnic minority populations ranged from 3.1% to 14.5%, compared with 7.6% among whites.
  [Centers for Disease Control and Prevention. 2004. Morbidity and Mortality Weekly Report. 53(07);145-148]
• Asthma and the environment: Connecting the dots
  Report explores the rapid increase in asthma rates in recent years which cannot be explained by genetic causes alone, as genetic changes require many generations for population-wide effects to occur, and because asthma rates are increasing among people without a family history of asthma and allergies.
  [Solomon, G., EH Humphreys, and MD Miller. 2004. Contemporary Pediatrics 21: 73]
• Early-Life Environmental Risk Factors for Asthma: Findings from the Children's Health Study
  To investigate further whether the timing of such experiences and exposures is associated with the occurrence of asthma by 5 years of age, authors conducted a prevalence case-control study nested within the Children's Health Study, a population-based study of > 4,000 school-aged children in 12 southern California communities. Asthma diagnosis before 5 years of age was associated with exposures in the first year of life to wood or oil smoke, soot, or exhaust , cockroaches , herbicides, pesticides, and farm crops, farm dust, or farm animals. The ORs for herbicide, pesticide, farm animal, and crops were largest among children with early-onset persistent asthma. The risk of asthma decreased with an increasing number of siblings. Day care attendance within the first 4 months of life was positively associated with early-onset transient wheezing.
  [Salam, MT, YF Li, B Langholz, and FD Gilliland. 2004. Environmental Health Perspectives 112 (6): 760-765]
• Health impacts of pesticide exposure in a cohort of outdoor workers.
  Study compared mortality of 1,999 outdoor staff working as part of an insecticide application program during 1935-1996 with that of 1,984 outdoor workers not occupationally exposed to insecticides, and with the Australian population. There was an increase in self-reported chronic illness and asthma, and lower neuropsychologic functioning scores among surviving exposed subjects when compared with controls.
  [Beard, J., et al. 2003. Environmental Health Perspectives 111(5):724-730]
• Respiratory symptoms in children and exposure to pesticides
  A cross­sectional study was performed on children from a randomly selected sample of Lebanese public schools. Exposure to pesticides was evaluated by a standardised questionnaire and a residential exposure score, and respiratory symptoms were assessed. A chronic respiratory disease was reported in 407 (12.4%) out of 3,291 children. The baseline difference in mean age was small but statistically significant. Any exposure to pesticides, including residential, para­occupational and domestic, was associated with respiratory disease and chronic respiratory symptoms (chronic phlegm, chronic wheezing, ever wheezing), except for chronic cough.
  [Salameh, PR, I Baldi, P Brochard, et al. 2003. European Respiratory Journal 22: 507-512]
• Respiratory symptoms in children and exposure to pesticides
  A cross­sectional study was performed on children from a randomly selected sample of Lebanese public schools. Exposure to pesticides was evaluated by a standardised questionnaire and a residential exposure score, and respiratory symptoms were assessed. A chronic respiratory disease was reported in 407 (12.4%) out of 3,291 children. The baseline difference in mean age was small but statistically significant. Any exposure to pesticides, including residential, para­occupational and domestic, was associated with respiratory disease and chronic respiratory symptoms (chronic phlegm, chronic wheezing, ever wheezing), except for chronic cough.
  [Salameh, PR, I Baldi, P Brochard, et al. 2003. European Respiratory Journal 22: 507-512]
• Occupational asthma from fungicides fluazinam and chlorothalonil.
  Authors report two cases of occupational asthma caused by sensitisation to powdered fungicides fluazinam and chlorothalonil, from the same fungicide formulation plant. Both developed work related lower respiratory symptoms after a latent interval of asymptomatic exposure. The diagnosis in each case was confirmed with a serial peak flow record in the workplace followed by specific inhalation tests. These fungicides are known to cause dermatitis; this report indicates that these compounds can induce specific immunological reactions in the airways as well as skin.
  [Draper, A, P Cullinan, C Campbell, et al. 2003. Occup Environ Med 60: 76-77]
• Asthma the Breathtaking Disease
  In the last 20 years, asthma rates have soared to epidemic levels. Johns Hopkins Bloomberg School Of Public Health researchers investigate the food we eat, the air we breathe, and the way our bodies work for clues to better asthma treatment and prevention.
  [Field, M. 2002. The Magazine of Johns Hopkins Bloomberg School Of Public Health]
• Identifying and managing adverse environmental health effects: 4. Pesticides.
  Pesticide exposure can cause many different health effects, from acute problems such as dermatitis and asthma exacerbation to chronic problems such as chronic obstructive pulmonary disease and cancer. The resulting clinical presentations are undifferentiated, and specific knowledge of the links to environmental exposures is often required for effective diagnosis. In this article we illustrate the use of the CH2OPD2 mnemonic (Community, Home, Hobbies, Occupation, Personal habits, Drugs and Diet), a history-taking tool that assists physicians in quickly identifying possible environmental exposures. We also provide clinical information on the epidemiology, clinical presentations, treatment and prevention of pesticide exposures.
  [Sanborn, MD, D Cole, A Abelsohn, and E Weir. May 28 2002. CMAJ 166 (11): 1431-1436]
• Hazardous air pollutants and asthma
  Complex mixtures (fine particulate matter and tobacco smoke) have been associated with respiratory symptoms and hospital admissions for asthma. Based on these observations and past experience with 188 hazardous air pollutants (HAPs), a list of 19 compounds that could have the highest impact on the induction or exacerbation of asthma was developed. Nine additional compounds were identified that might exacerbate asthma based on their irritancy, respirability, or ability to react with biological macromolecules. Recommendations for research are presented regarding exposure monitoring and evaluation of biologic mechanisms controlling how these substances induce and exacerbate asthma.
  [Leikauf, GD. 2002. Environmental Health Perspectives 110 (Suppl 4): 505-526]
• Chemical predictors of wheeze among farmer pesticide applicators in the Agricultural Health Study.
  Using the Agricultural Health Study, a large cohort of certified pesticide applicators in Iowa and North Carolina, authors explored the association between wheeze and pesticide use in the past year. Self-administered questionnaires contained items on 40 currently used pesticides and pesticide application practices. A total of 20,468 applicators, ranging in age from 16 to 88 years, provided complete information; 19% reported wheezing in the past year. The herbicides, atrazine and alachlor, but not 2,4-D, were associated with wheeze. Atrazine had a significant dose-response trend with participants applying atrazine more than 20 days/year.These associations, though small, suggest an independent role for specific pesticides in respiratory symptoms of farmers.
  [Hoppin, JA, DM Umbach, SJ London, et al. 2002. M J Respir Crit Care Med 165: 683-689]
• Fatal asthma in a child after use of an animal shampoo containing pyrethrin
  This case suggests that physicians should also be alert to formulations marketed as pyrethrin.Pesticides of this class are being used with increasing frequency in homes and are easily available to the public. Manufacturers are not required by the Environmental Protection Agency to state on the label that the pyrethrum formulations are allergens. The possibility of an acute allergic reaction occurring from the use of any currently marketed pyrethrum insecticide should be considered in any case of respiratory or dermal allergy of unknown cause.
  [Wagner, SL. 2000. West J Med 173: 86-87]
• Asthma to tetramethrin.
  Case report of occupational asthma following exposure to tetramethrin.
  [Vandenplas, O, JP Delwiche, J Auverdin, et al. 2000. Allergy 55: 418-419]
• Exposures of children to organophosphate pesticides and their potential adverse health effects.
  Research findings suggest that it is biologically plausible that organophosphate exposure may be related to respiratory disease in children through dysregulation of the autonomic nervous system. This Center for the Health Assessment of Mothers and Children of Salinas, or CHAMACOS in Monterey County, California, will assess (italic)in utero(/italic) and postnatal organophosphate pesticide exposure and the relationship of exposure to neurodevelopment, growth, and symptoms of respiratory illness in children.
  [Eskanazi, B, A Bradman, and R Castorina. 1999. Environmental Health Perspectives 107(Suppl 3): 409-419]
• Is the increase in asthma prevalence occurring in children without a family history of atopy?
  Study investigated the familial associations of asthma and atopic disease in a population in which the prevalence of asthma and atopy is increasing. The prevalence of reported asthma (22.5%), eczema (24%) and hayfever (20%) in the children was high but similar to previous studies in this population. Asthma was reported in 20.8% of children of parents without a history of asthma and 18% of children of parents without any history of atopic disease. In children of parents without a family history of atopic disease suggests that much of the increase in asthma prevalence is occurring in children without a significant genetic predisposition. Childhood asthma developing in what would previously have been regarded as low risk families may differ in its aetiology from classical atopic asthma.
  [Christie GL, McDougall CM, Helms PJ. 1998. Is the increase in asthma prevalence occurring in children without a family history of atopy? Scott Med J. 43 (6): 180-182]
• Five office workers inadvertently exposed to cypermethrin.
  Five cases of poisoning by cypermethrin, a pyrethroid pesticide, are presented. The chemical was inadvertently introduced to the air-conditioning ducts and the patients inhaled it. Exposed patients experienced shortness of breath, nausea, headaches, and irritability. The exposure was compounded by repeated entry into the contaminated area and slow referral to a physician experienced in pesticide exposures.
  [Lessenger JE. 1992. J Toxicol Environ Health 35: 261-267]
• Indoor spraying with the pyrethroid insecticide lambda-cyhalothrin: effects on spraymen and inhabitants of sprayed houses.
  In March 1990 a study was carried out in the village of Kicheba, United Republic of Tanzania, in which the pyrethroid insecticide lambda-cyhalothrin was sprayed on all the internal surfaces of houses and other shelters at a coverage of about 25 mg of active ingredient per m2. All the spraymen complained at least once of symptoms that were related to exposure to lambda-cyhalothrin, the commonest being itching and burning of the face, and nose or throat irritation frequently accompanied by sneezing or coughing. Facial symptoms occurred on non-protected areas only. The number of subjects affected and the duration of their facial symptoms were proportional to the amount of compound sprayed.
  [Moretto A. 1991.Bull WHO 69 (5): 591-594]
• Asthmatic reactions to a commonly used aerosol insect killer.
  Seven patients with asthma and a history of chest tightness on exposure to aerosol insecticide sprays were studied. Under controlled conditions, objective measures of airways narrowing were taken before and after exposure to an aerosol insect killer (Mortein Pressure Pak). Chest tightness described as asthma was produced in all seven subjects, but only one showed a greater than 20% fall in FEV1, compared to baseline values. A further two subjects showed small changes in the maximum mid-expiratory flow rate. No changes were observed in the subjects' sensitivity to inhaled histamine before, and 24 hours after, exposure to the insecticide. Thus, exposure to a commonly used household insecticide spray produced marked symptoms in all subjects, but objective evidence of airways obstruction was present in only three, and no changes in bronchial reactivity to inhaled histamine occurred in any of the subjects
  [Newton JG and Breslin AB.1983. Med J Aust.1(8):378-80]
• Occupational exposure to some synthetic pyrethroids (permethrin and fenvalerate).
  In a two-step study on exposure control method for occupational handling of permethrin was developed. Air sampling on a filter can be used in case of exposure to permethrin in powder form. The detection limit is 0.001 mg/m3. If biological sampling is used, the acid metabolite moiety in the urine must be monitored. However, the uptake after exposure to permethrin in forestry was too low, and no urine concentration could be found. The detection limit is 0.1 microgram/ml. Six persons in a plant nursery and six planters were studied in this way. Interviews were conducted with 139 planters. Irritative symptoms form the skin and upper respiratory tract were reported in 73% for fenvalerate, 63% for permethrin (trans/cis 75/25) and 33% for permethrin (trans/cis 60/40).
  [Kolmodin-Hedman, B, A Swensson, and M Akerblom. 1982. Arch Toxicol 50: 27-33]
• Insecticides: household use and respiratory impairment
  An early study done in the 1960s in Hawaii shows that frequent household use of insecticides is correlated with an increased prevalence of respiratory disorders, including asthma and chronic bronchitis. The majority of the household pesticides used were insect sprays for mosquitoes, flies, and cockroaches
  [Weiner, BP, and RM Worth. 1969. Hawaii Medical Journal 28 (4): 283-285]