| Abstrakt: |
Objective To investigate the pollution characteristics of major heavy metals in PM2.5 in urban areas of Haikou City, and to assess their potential health risks to humans. Methods From 2021 to 2022, samples of atmospheric PM2.5 were monthly collected from the typical urban areas of Haikou, and the concentrations of nine heavy metal elements including arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), nickel (Ni), copper (Cu), vanadium (V), and zinc (Zn) were measured using the inductively coupled plasma mass spectrometry (ICP-MS). The health risk assessment of these heavy metals was conducted using a health risk model. Results The average mass concentration of PM2.5 in Haikou was (20.506±13.054) µg/m³, with a range of 4.000 to 64.000 µg/m³ during the year 2021 and 2022. The PM2.5 concentrations showed significant seasonal variations: highest in winter, followed by autumn and spring, and lowest in summer. The total concentration of the nine heavy metal elements ranged from 0.030 to 138.000 ng/m³, with Zn, Mn, and Pb having the highest concentrations, particularly notable during the autumn and winter seasons. Enrichment factor (EF) analysis indicated moderate enrichment (10-5 to 3.068x10-1), with the HQ values ordered as follows: Mn > Cd > Cr > As > Pb > V > Zn > Cu > Ni. The total non-carcinogenic hazard index (HI) ranged from 0.171 to 0.361. The inhalation incremental lifetime carcinogenic risk values (ILCR) for the four elements Cr, As, Cd, and Ni ranged from 2.911x10-7 to 1.558x10-5, with ILCR decreasing in that order. The total carcinogenic risk index (TR) varied between 1.502x10-5 and 3.169x10-5, with risk intensities for HI and TR in the order: children > adult males > adult females. Conclusions The average PM2.5 concentration in the Haikou urban area is lower than the 24-hour average concentration limit of Grade I (35 µg/m³) in the "Environmental Air Quality Standard" (GB 3095-2012), but still higher than the control standard recommended by the WHO in 2021 (15 µg/m³). The non-carcinogenic health risks of the nine heavy metal elements detected in PM2.5 are not significant, but Cr and As have potential carcinogenic risks, with children being more vulnerable than other populations. [ABSTRACT FROM AUTHOR] |
