Longitudinal investigation of haematological alterations among permethrin-exposed pesticide applicators in the Biomarkers of Exposure and Effect in Agriculture study

Abstract

ObjectivesPermethrin use has been associated with an increased risk of multiple myeloma (MM) among pesticide applicators. However, the biological plausibility and mechanisms underlying this association are not fully understood. The aim of this study was to assess whether exposure to permethrin is related to haematological alterations among occupationally exposed pesticide applicators.MethodsWe conducted a longitudinal study among 33 pesticide applicators in the Biomarkers of Exposure and Effect in Agriculture study comparing haematological parameters in the offseason with the day after permethrin exposure and, for 27 participants, approximately 3 weeks postexposure. Complete blood counts with white blood cell differential and lymphocyte subsets were measured at each visit. Multivariate linear mixed effects models were used to assess the relationship between natural log-transformed haematological parameters and exposure to permethrin.ResultsThe adjusted geometric mean immature granulocyte count was elevated among pesticide applicators following permethrin exposure compared with their offseason levels (37% increase, 95% CI 6% to 76%). Modest but statistically significant (p<0.05) alterations in red blood cell (RBC) parameters (eg, decreased RBC count and haemoglobin and increased mean corpuscular volume and RBC distribution width-SD) were also observed the day after permethrin use compared with offseason levels; decreases in RBC count and haemoglobin and increases in RBC distribution width-SD persisted approximately 3 weeks after permethrin use.ConclusionsAltered haematological parameters could be indicative of disrupted haematopoiesis, providing insights into the biological plausibility of the observed association between permethrin use and MM risk among pesticide applicators.

Cancer and occupational exposure to pesticides: a bibliometric study of the past 10 years

“…The vast majority of the studies were based on either the monitoring of cohorts ( n = 24; 38.71%) or the case–control approach ( n = 23; 37.1%). The other studies were based on a cross-sectional approach ( n = 9; 14.52%), longitudinal monitoring ( n = 3; 4.84%), and a descriptive or biomonitoring approach, each used in one (1.61%) study (Rusiecki et al 2017 ; Kumar et al 2018 ; Joshi et al 2019 ; Shearer et al 2019 ). However, no significant variation was found ( F (2;27) = 1.9939, p = 0.154) in the application of the three most frequently-used approaches (cohort, case–control or cross-sectional studies) among the different years of the study period.…”

Occupational Risk Exposures and Adverse Health Findings Among Farmers in Southern Philippines

“…Certain pesticides, such as permethrin, were also observed to cause injury and death of red blood cells in the body, further contributing to the observed decrease in RBC count and hemoglobin levels. 45 As for the increased lymphocyte and eosinophil, the study conducted by Hassanin et al observed that their sample's neutrophil levels decreased while eosinophil levels increased. 20 It is hypothesized that short-term exposure's impact was on the already developed peripheral blood components, while long-term exposure's effect was directed towards the bone marrow.…”

“…Abnormalities in blood parameters were observed among participants in other studies. 16,20,30,45 A study done by Shearer et al observed that pesticide-exposed individuals exhibited increased immature granulocyte count and decreased RBC count and hemoglobin levels in comparison to their off-season results. 45 The researchers explained that this occurred due to an inflammatory response that triggered an increase in the immature granulocyte count.…”

“…16,20,30,45 A study done by Shearer et al observed that pesticide-exposed individuals exhibited increased immature granulocyte count and decreased RBC count and hemoglobin levels in comparison to their off-season results. 45 The researchers explained that this occurred due to an inflammatory response that triggered an increase in the immature granulocyte count. However, these failed to reach maturity, explaining the decrease in RBC count and hemoglobin levels.…”

Lifetime Pesticide Use and Monoclonal Gammopathy of Undetermined Significance in a Prospective Cohort of Male Farmers

“…In the AHS, exposure to permethrin has been consistently associated with an increased risk of MM among pesticide applicators, with a significant exposure-response trend (Alavanja et al 2014;Rusiecki et al 2009). Furthermore, in a longitudinal study among a subset of BEEA participants with serial sample collections timed specifically in relation to permethrin exposure (Shearer et al 2019), we observed early subclinical alterations in several hematologic parameters (e.g., decreased red blood cell counts, increased immature granulocytes) in samples collected the day after permethrin use relative to off-season levels, which may be indicative of disrupted hematopoiesis. These findings, taken together with the results of the present study demonstrating an association with MGUS for recent use, especially in combination with past use, provide consistent evidence supporting a link between permethrin and MM development.…”