Environmental and human health risk of heavy metals in atmospheric particulate matter (PM10) around gas flaring vicinity in Bayelsa State, Nigeria

Background: Exposure to elevated concentrations of heavy metal micro-pollutants is a serious environmental issue. Often times, metals are suspended in air as vapor. It also biomagnifies across the food chain, causing adverse health conditions in human. This study evaluated the risks of heavy metals in atmospheric particulate matter (PM10) around gas flaring vicinity in Bayelsa State, Nigeria. Materials and methods: Using Particulate matter sampler APM131 monitor, suspended particulate was sampled across eight locations. Sample measurements were obtained within 3000 m distance of the gas flaring facility, while a control point was established at over 7000 m distance from the flare stark. Afterward, filter was analyzed for trace/heavy metals using the atomic absorption spectrometer. Results: The mean concentration of heavy metals ranged from 0.017 to 0.060, 0.050 to 0.197, 0.027 to 1.280, 0.050 to 0.170, 0.037 to 0.310 and 6.717 to 8.233 µg/m3 for arsenic, cobalt, chromium, cadmium, copper and iron, respectively. Pollution indices reflected low-to-moderate pollution, while ecological risk index showed low risk. Index of geoaccumulation and enrichment factor depicts anthropogenic activities as the prevalent source of heavy metals in atmospheric PM10 of the area. The carcinogenic and non-carcinogenic risks revealed values that were within the threshold limits. Conclusion: Heavy metals in air around the study area has no adverse health effect on inhabitants within the considered age bracket. However, due to the presence of these metals in atmospheric PM10 within the study area, there is a need for the studied parameters to be included in the routine emission inventories.