Evaluation of the impacts of occupational exposure to PM and PAH on cardiovascular problems in wastewater treatment plant workers

Abstract

Abstract Background Workers in wastewater treatment plant (WWTPs) are at high risk of developing various infections and cardiovascular diseases (CVD). Aims of the study were estimation of the concentrations of 16 EPA priority polycyclic aromatic hydrocarbons (PAHs) and particulate matters (PM) with different sizes in air of WWTP, and prediction of CVDs to evaluate the potential risk of developing CVDs in the WWTP workers due to their occupational exposures, in addition to identification of the CVDs` risky work tasks. Methodology: PM concentrations, and wind rose plots for meteorological data, were monitored for 24 months. Estimation of the individual PAHs in suspended particulate matter samples and identification of sources were done. Cross-sectional study was done on 142 male workers from WWTP. All participants were subjected to occupational and medical questionnaire, electrocardiogram (ECG), and measurement of blood pressure. Serum APO-A, APO-B, APO-E, and Lipoprotein α (Lpα) were estimated for all participants. Results The annual mean concentrations of PM (PM1, PM2.5, PM10 and TSP) were lower than Egyptian limit. EPA 16 PAHs were detected in all samples, lower molecular weight PAHs were the most predominant PAHs. The most predominant wind direction was from North-West; as the selected WWPT is placed downwind to the surrounding areas. Fifty percent of the workers were complaining of dyspnea. About 30.9% of the workers were found to be hypertensive; the majority of them were from the operator department. ECG abnormalities were found in 18.3% of the workers mainly among operators (23.95%). Ventricular extra systole was the highest prevalent detected ECG abnormality followed by left ventricular enlargement. APO-B and APO-B/APO-A ratio were significantly higher in operator workers compared to the administrators and laboratory workers. While, APO-E was significantly lower in operator workers compared to the administrators and laboratory workers. Conclusion PM2.5 and PM1 and PAH exposure maybe associated with potential risk of developing CVD in the exposed WWTP workers. The main sources of PAHs in the WWTP could be the fuel used for the machines in the operator department, as the treatment process occurs in the WWTP contribute to high concentrations of PM and its PAHs, but the most contributed sources were found to be from the surrounding areas. The use of APO-B or APO-B/APO-A holds a promising biomarkers for evaluating cardiovascular disease risk.