Background: Vector Control Workers (VCW) play a vital role in public health strategies in Brazil, working directly to control vectors of diseases such as dengue, Zika, and malaria. Paradoxically, these activities are centered on the intensive use of pesticides, including organochlorines and organophosphates. Many of these substances are already banned in European countries and classified as "probably carcinogenic to humans" (Group 2A) by the International Agency for Research on Cancer (IARC), such as Dichlorodiphenyltrichloroethane (DDT) and Malathion. The exposure to these substances can cause acute and chronic effects, contributing to early mortality among these workers; in the state of Rio de Janeiro, approximately 40 deaths occur annually with an average age of 55, within a population of 6,000 federal servants.
Objectives: To evaluate pesticide exposure and its effects on hematological, biochemical, immunological, and inflammatory profiles in VCW from the Brazilian Ministry of Health operating in Rio de Janeiro.
Methods: A cross-sectional epidemiological study was conducted involving 127 occupationally exposed VCW and 67 non-exposed workers (control group). The research was approved by the Ethics Committee of the Sergio Arouca National School of Public Health (ENSP), opinion No. 03323018.4.0000.5240. Blood samples were collected for hematological, biochemical, and immunological analyses, as well as for pesticide residue detection.
Results: Among the VCW, residues of the organochlorine DDT were detected in 52%, and Hexachlorocyclohexane (HCH) in 12%. A significant number of workers showed laboratory parameters outside reference levels: 73% presented dyslipidemia (altered cholesterol and triglycerides), 47% showed impaired renal function, and 44% had alterations in the erythrogram. At the cellular level, a decrease in the percentage of peripheral blood mononuclear cells (PBMC) was observed in VCW after a 72-hour culture compared to the control group, along with lower levels of nitric oxide. Despite the lower cell count, VCW exhibited higher levels of IL-17A and TNF-alpha, as well as increased IL-10, indicating both a pro-inflammatory and a regulatory response. Furthermore, 75% reported symptoms of intoxication after handling pesticides, 31% received no training regarding the use and hazards of these substances, and 73% reported the onset or worsening of health problems associated with their professional activity.
Conclusion/Implications: The data evidence the toxicity to which these workers are subjected and the urgent need for continuous health surveillance. The VCW work process must be revised, as the current strategy replaces pesticides only when mosquito resistance is detected, rather than considering the toxic potential to human health. Public health campaigns must reevaluate the use of these chemical products, given their harmful effects on workers' hematological, biochemical, and immunological integrity.