Objective The aims were to provide reference data for the environmental assessment and health risk assessment of 16 Polycyclic aromatic hydrocarbons (PAHs) in the soil of the green belt in Guiyang City.

Methods The content of polycyclic aromatic hydrocarbons (PAHs) in soil samples of 30 green belts in 6 main urban areas of Guiyang City was determined by gas chromatography triple quadrupole mass spectrometer with selected ion mode.

Result PAHs in soil of green belt mainly came from exogenous pollution. Six PAHs met the national construction land risk screening value standard, but the overall proportion of pollution is high. In the functional area of night market, a large amount of PAHs were produced by two main ways of barbecue and frying, which made the soil concentration in the adjacent green belt significantly higher than that in other functional areas. The results of characteristic ratio method showed that the combustion of biomass fuels (such as coal) occupied a certain proportion of the emission contribution sources of the residential area, and the main emission contribution source of the school functional area was the oil combustion exhaust emissions from motor vehicles. In terms of health risk assessment, skin contact was the main route of carcinogenic risk.

Conclusion The proportion of the green belt contaminated soil in the main urban area of Guiyang City was relatively high, and the content of high molecular weight (4-6 rings) PAHs was higher than that low molecular weight (2-3 rings) PAHs. PAHs in green belt soil are potentially carcinogenic to children and adults. Therefore, corresponding measures should be taken to reduce pollution sources and pollution degree.