Distribution characteristics, source appointment, and health risk assessment of Cd exposure via household dust in six cities of China

This study investigated the characteristics and health risks of cadmium (Cd) in household dust in urban and rural areas during heating and non-heating periods. Seven hundred and sixty-two dust samples and 381 questionnaires were collected from households in the Chinese cities of Dalian, Taiyuan, Lanzhou, Shanghai, Wuhan, and Chengdu. The Cd concentration results of household dust indicated higher levels in urban areas and in heating periods because of the complex mankind activities and environmental influence factors. A correlation analysis and redundancy analysis demonstrated that smoking, cooking, and ventilation time were vital influencing factors for Cd levels in household dust. Cd in the indoor air, outdoor air, traffic air, and soil also contributed to the Cd in the household dust, among which soil contributed the most. The non-carcinogenic and carcinogenic risks of Cd in the household dust were acceptable. Ingestion was the primary pathway for residents' exposure to Cd in household dust. And the different exposure behavior patterns of population in the study areas had a great impact on the health risk assessment results.