Hematological and cardiovascular effects of chronic low level lead exposure: A study on e-waste recyclers

Abstract

BackgroundChronic exposure to lead is detrimental, despite exposed to very low levels. Hematological and cardiovascular system are among the commonly affected systems due to chronic lead exposure. With tremendous progressive usage electrical and electronic products, they are being scrapped, recycled and refurbished by process of e-waste recycling. Primitive e-waste recycling activities are increasingly popular and contributes substantially to the economy and employment. However, the e-waste recycling process is a source of occupational lead exposure. ObjectiveTo evaluate the influence of chronic lead exposure on the hematological and cardiovascular parameters among e-waste recyclers with variable levels of lead exposure. MethodologyAll workers from two e-waste recycling units with significantly different lead levels were recruited after informed consent. Socio-demographic, occupational and clinical details of all participants were recorded. Environmental and blood lead levels (BLL) were evaluated using graphite furnace atomic absorption spectroscopy (GF-AAS). The hematological parameters and cardiovascular parameters were assessed using standard tools. Group differences and multivariate regression analysis to achieve the objectives was performed using Statistical Package for Social Science version 17.0. ResultsSixty-four Workers employed (32 from each recycling unit) in these recycling units were exposed to significantly different levels of lead, however the levels were well within the permissible limits. Workers exposed to higher environmental lead levels had significantly higher BLL & diastolic blood pressure (DBP) as compared to their comparators. Further, workers with higher BLL exhibited a trend of reduced hemoglobin as compared to the workers with lower BLL. However, the study observed a trend of changes (hematological & cardiovascular) consistent to the possible homeostasis mechanisms of reduced hemoglobin. Elevation in blood pressure (BP), a known compensatory response to peripheral hypoxia (due to reduced hemoglobin), observed in the current study could either be due to direct and indirect (reduced hemoglobin) influence of lead exposure. ConclusionIndividuals chronically exposed to Lead, despite within the permissible levels can exhibit detrimental effects. Present results indicate the direct and indirect (reducing hemoglobin) mechanisms by which lead would influence BP. Future studies are recommended to confirm the present results.