Characteritization of, and health risks from, polychlorinated dibenzo-p-dioxins/dibenzofurans from incense burned in a temple

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) may cause adverse health effects. However, PCDD/F emissions from burning incense in temples have rarely been addressed. This study investigates PCDD/F emissions from burning incense in a temple. The mean total PCDD/F concentrations were 72.4–82.2 pg Nm− 3 at two indoor sites; their corresponding mean total PCDD/Fs I-TEQ concentrations (0.24–0.27 pg I-TEQ Nm− 3) were ~ 11 times that at a background location. In air samples collected from burning incense, OCDFs accounted for approximately 90% of total PCDD/Fs at the two indoor sites and an outdoor site near the temple, while the major PCDD/Fs in incense ash were PCDDs. The total PCDD/F content and toxic equivalent value of incense ash were 617 pg g− 1 and 1.55 pg I-TEQ g− 1, respectively. At the three sites inside/outside the temple, the air and ash samples contained the same four primary PCDD/Fs–OCDD, 1,2,3,4,6,7,8-HpCDD, OCDF and 1,2,3,4,6,7,8-HpCDF. The Cl− emission factor, which is related to the PCDD/F formation, from burning incense was 0.454 mg g− 1. The resultant lifetime average daily dose and cancer risk for temple workers were 0.00964 pg I-TEQ day− 1 kg− 1 and 9.64 × 10− 6, respectively, approximately 2 times that for residents near the temple (0.00489 pg I-TEQ day− 1 kg− 1 and 4.89 × 10− 6, respectively). We suggest that the chlorine content in incense must be regulated, and the high risk of PCDD/F exposure from burning incense for temple workers and visitors should be of concern.