Exposure to secondhand and thirdhand smoke in private vehicles: Measurements in air and dust samples

Background: This study aimed to estimate airborne nicotine concentrations and nicotine, cotinine, and tobaccospecific nitrosamines (TSNAs) in settled dust from private cars in Spain and the UK. Methods: We measured vapor-phase nicotine concentrations in a convenience sample of 45 private cars from Spain (N = 30) and the UK (N = 15) in 2017-2018. We recruited non-smoking drivers (n = 20), smoking drivers who do not smoke inside the car (n = 15), and smoking drivers who smoke inside (n = 10). Nicotine, cotinine, and three TSNAs (NNK, NNN, NNA) were also measured in settled dust in a random subsample (n = 20). We computed medians and interquartile ranges (IQR) of secondhand smoke (SHS) and thirdhand smoke (THS) compounds according to the drivers' profile. Results: 24-h samples yielded median airborne nicotine concentrations below the limit of quantification (LOQ) (IQR:

Automated summary

This study estimated the levels of airborne nicotine and the presence of nicotine, cotinine, and TSNAs in settled dust from private cars in Spain and the UK. The results showed that smoking inside the car significantly increased the levels of secondhand smoke and thirdhand smoke.