Airway Inflammation and Upregulation of β₂ Mac‐1 Integrin Expression on Circulating Leukocytes of Female Ragpickers in India

Abstract

Over one million ragpickers collect and sale recyclable materials from municipal solid wastes (MSW) in India for a living. Since MSW contains a host of pathogenic microorganisms, we investigated the occurrence of airway inflammation and its underlying mechanism in 52 non-smoking female ragpickers (median age 29 yr) and 42 control women matched for age, smoking habit and socioeconomic conditions in Kolkata, eastern India. Methods: Spontaneously expectorated sputum were stained using the Papanicolau method for cytology, and flow cytometry was used for measurements of surface expression of β 2 Mac-1 integrin (CD11b/CD18) on leukocytes and P-selectin on platelets. The concentrations of pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) and chemokine interleukin-8 (IL-8) were measured in plasma by enzyme-linked immunosorbent assay. Results: Compared with controls, sputum samples of ragpickers contained significantly increased numbers of alveolar macrophages, neutrophils, eosinophils and lymphocytes, suggesting airway inflammation. Circulating neutrophils and monocytes of the ragpickers overexpressed CD11b/CD18 and their platelets had upregulated surface expression of P-selectin, implying functional activation of these cells. In addition, plasma levels of IL-8 and TNF-α were significantly increased, indicating greater trafficking of leukocytes from circulation to the tissues. Multivariate logistic regression analysis demonstrated a positive association between the ragpicking profession and leukocyte activation after controlling for potential confounders. Conclusions: Ragpickers experience leukocyte and platelet activation and airway inflammation that could make them more vulnerable to tissue damage and cardiovascular diseases. (J Occup Health 2009; 51: 232-238)

Alteration in Leukocyte Subsets and Expressions of FcγR and Complement Receptors among Female Ragpickers in Eastern India

“…The key components of defense against invading microorganisms are inflammation and repair of tissue injury. In view of these reports, the increase in CD16+ monocytes in ragpickers can be attributed in part to higher platelet P-selectin expression as we reported earlier in female ragpickers of Kolkata [6].…”

“…Neutrophil influx from blood to the tissues is driven in large part by interleukin-8, a strong neutrophil chemoattractant. Therefore, the upregulation of CR1 and CR3 expressions on circulating leukocytes along with higher interleukin-8 levels, as we have reported earlier among female ragpickers [6], may suggest increased neutrophilic inflammation in ragpickers. However, the complement molecules may induce undesirable inflammation if activated improperly or uncontrolled; thus acting as a double-edged sword in that sense.…”

“…Although ragpickers constitute the poorest of the poor in Kolkata, little is known about the health hazard associated with this profession. Earlier we reported the problems of the general respiratory health of ragpickers in India [5], [6]. We found a significant reduction in lung function in the majority of ragpickers and the majority of them had airway obstruction [5].…”

Possible role of plasma ceruloplasmin and erythrocyte sedimentation rate in assessing compliance with occupational hygiene and safety practices in waste management workers

“…[41] The WMWs are the most vulnerable to waste hazards because of their direct involvement in the disposal of waste, and evidence abounds on work-related health and safety risks among these individuals. [210121642] We identified some important systemic inflammatory markers as useful biomonitors of health and safety of WMWs of Ogun State, South-West Nigeria, in our recent study. [19] In the present investigation, we evaluated the possibility of using these systemic inflammatory indices as predictors and bioindicators of compliance of WMWs with safety practices with particular reference to those in the CPs and TUs categories.…”

“…[2] Collection of waste varies from informal manual gathering to semiautomated systems and involves the removal of waste materials from households, typically in urban and suburban areas, to either the point of recycling or final disposal. [2] Several studies have reported the existence of work-related health and safety risks for waste collectors such as exposure to elevated concentrations of biological aerosols,[34567] respiratory and gastrointestinal complaints,[289101112] infectious diseases like hepatitis A, B, and C, HIV, and syphilis. [131415]…”