Classroom Dust-Bound Polycyclic Aromatic Hydrocarbons in Jeddah Primary Schools, Saudi Arabia: Level, Characteristics and Health Risk Assessment

Abstract

Data concerning polycyclic aromatic hydrocarbons (PAHs) in Jeddah’s schools, Saudi Arabia, and their implications for health risks to children, is scarce. Classroom air conditioner filter dusts were collected from primary schools in urban, suburban and residential areas of Jeddah. This study aimed to assess the characteristics of classroom-dust-bound PAHs and the health risks to children of PAH exposure. Average PAH concentrations were higher in urban schools than suburban and residential schools. Benzo (b)fluoranthene (BbF), benzo(ghi)perylene (BGP), chrysene (CRY) and Dibenz[a,h]anthracene (DBA) at urban and suburban schools and BbF, BGP, fluoranthene (FLT) and indeno (1, 2, 3, −cd)pyrene (IND) at residential schools were the dominant compounds in classroom dust. PAHs with five aromatic rings were the most abundant at all schools. The relative contribution of the individual PAH compounds to total PAH concentrations in the classroom dusts of schools indicate that the study areas do share a common source, vehicle emissions. Based on diagnostic ratios of PAHs, they are emitted from local pyrogenic sources, and traffic is the significant PAH source, with more significant contributions from gasoline-fueled than from diesel cars. Based on benzo[a]pyrene equivalent (BaPequi) calculations, total carcinogenic activity (TCA) for total PAHs represent 21.59% (urban schools), 20.99% (suburban schools), and 18.88% (residential schools) of total PAH concentrations. DBA and BaP were the most dominant compounds contributing to the TCA, suggesting the importance of BaP and DBA as surrogate compounds for PAHs in this schools. Based on incremental lifetime cancer risk (ILCingestion, ILCRinhalation, ILCRdermal) and total lifetime cancer risk (TLCR)) calculations, the order of cancer risk was: urban schools > suburban schools > residential schools. Both ingestion and dermal contact are major contributors to cancer risk. Among PAHs, DBA, BaP, BbF, benzo(a)anthracene (BaA), benzo(k)fluoranthene (BkF), and IND have the highest ILCR values at all schools. LCR and TLCR values at all schools were lower than 10−6, indicating virtual safety. DBA, BaP and BbF were the predominant contributors to cancer effects in all schools.

Insights into the house dust-bound polycyclic aromatic hydrocarbons and their potential human health risk in Greater Cairo, Egypt

“…Mean ƩPAH concentration levels in settled dust of GCH (3125 ng/g) were higher than those reported in comparable studies: Greece, SW and NM (397 ng/g), 80 Kuwait, Kuwait City (2150 ng/g), 81 Nigeria, Emu-Unor (60–1473 ng/g), 58 Nigeria, Abraka (124–2131 ng/g), 58 Iran, Tehran (131–429 ng/g), 23 Kuwait, 90 cities (1112 ng/g) 82 and Saudi Arabia, Jeddah (2004 ng/g). 51 The PAH concentrations found in the present study were lower than those found in Hong Kong (6070 ng/g), 43 USA, Colorado (3358 ng/g), 83 UK, Cambridge (5095 ng/g), 83 and Brazil, Northeast of Rio Grande do Sul (4091 ng/g). 84…”

Benzo[a]pyrene—Environmental Occurrence, Human Exposure, and Mechanisms of Toxicity

“…The analysis also revealed that the combustion of coal and gasoline mainly contributed to B[ a ]P presence in the indoor environment of tested buildings. In another study, Alghamdi et al [ 33 ] determined classroom, dust-bound PAHs, including B[ a ]P, in Jeddah’s schools in Saudi Arabia. The authors detected B[ a ]P at a very high mean concentration of 163.87 ± 68.53 ng/m 3 , noting that mean PAHs levels were higher in classrooms in urban schools as compared to suburban and residential schools.…”

Quantification and Risk Assessment of PAHs in Street Dust from Functional Areas of Khamis-Mushait, Saudi Arabia

“…Another study was conducted in Jeddah's schools to evaluate the concentration levels of PAHs (indoor) in air conditioner filter dust of some primary schools in Jeddah city. In all schools DBA, BaP and BbF were the predominant contributors to cancer effect [10,11]. Recorded PAHs ranged from 90-22146 ng/g with an average of 4096 ng/g in dust from different carpets of mosques in Riyadh city.…”