Semi-Volatile Organic Compounds in Car Dust: A Pilot Study in Jeddah, Saudi Arabia.

People may spend a significant amount of their daily time in cars and thus be exposed to chemicals present in car dust. Various chemicals are emitted from during car use, contaminating the car dust. In this study, we compiled published and unpublished data on the occurrence of phthalates, flame retardants (FRs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in Saudi car dust. Phthalates, a class of chemical commonly used as plasticizers in different car parts, were the major pollutants found in car dust, with a median value of ∑phthalates 1,279,000 ng/g. Among other chemicals, organophosphate flame retardants (OPFRs) were found to be between 1500-90,500 ng/g, which indicates their use as alternative FRs in the car industry. The daily exposure to Saudi drivers (regular and taxi drivers) was below the respective reference dose (RfD) values of the individual chemicals. However, the estimated incremental lifetime cancer risk (ILCR) values due to chronic exposure to these chemicals was >1 × 10-5 for taxi drivers for phthalates and PAHs, indicating that the long-term exposure to these chemicals is a cause of concern for drivers who spend considerable time in cars. The study has some limitations, due to the small number of samples, lack of updated RfD values, and missing cancer slope factors for many studied chemicals. Despite these limitations, this study indicates the possible range of exposure to drivers from chemicals in car dust and warrants further extensive studies to confirm these patterns.

Polycyclic Aromatic Hydrocarbons in Indoor Dust Collected during the COVID-19 Pandemic Lockdown in Saudi Arabia: Status, Sources and Human Health Risks.

To control the spread of coronavirus disease (COVID-19), Saudi Arabia's government imposed a strict lockdown during March-July 2020. As a result, the public was confined to indoors, and most of their daily activities were happening in their indoor places, which might have resulted in lower indoor environment quality. Polycyclic aromatic hydrocarbons (PAHs) were analyzed in household dust (n = 40) collected from different residential districts of Jeddah, Saudi Arabia, during the lockdown period. PAHs' levels were two folds higher than the previously reported PAHs in indoor dust from this region. We detected low molecular weight (LMW) with two to four aromatic ring PAHs in all the samples with a significant contribution from Phenanthrene (Phe), present at an average concentration of 1590 ng/g of dust. Although high molecular weight (HMW) (5-6 aromatic ring) PAHs were detected at lower concentrations than LMW PAHs, however, they contributed >90% in the carcinogenic index of PAHs. The estimated daily intake (EDI) of specific PAHs was above the reference dose (RfD) for young children in high-end exposure and the calculated Incremental Lifetime Cancer Risk (ILCR) was >1.00 × 10-4 for both Saudi adults and young children. The study highlighted that indoor pollution has increased significantly during lockdown due to the increased indoor activities and inversely affect human health. This study also warrants to conduct more studies involving different chemicals to understand the indoor environment quality during strict lockdown conditions.

Arsenic and lead in the indoor residential settings of different socio-economic status; assessment of human health risk via dust exposure.

In the present study, occurrence of arsenic (As) and lead (Pb) is reported in rural and urban household dust (floor and AC filter dust) of the Kingdom of Saudi Arabia (KSA). Several studies have found concerning concentrations of these toxic metals in indoor dust from different countries, but data from this region is missing. The association between studied toxic metals and different socioeconomic parameters was investigated. Furthermore, health risk associated with these toxic metals via dust exposure was evaluated for the Saudi population. Mean concentration of Pb was several times higher than As in both types of dust samples. AC filter dust was more contaminated with these metals than floor dust. Levels of Pb were up to 775 ppm in AC filter dust from urban areas, while 167 ppm in rural AC filter dust. Different socioeconomic parameters did not influence much on the presence of studied metals in both AC and floor dust. To estimate health risk from contaminated dust hazardous index (HI), hazardous quotient (HQ), and incremental lifetime cancer risk (ILCR) via dust ingestion, inhalation, and dermal contact was calculate using USEPA equations. The ILCR range for both toxic metals was within the tolerable range of reference values of USEPA (1 × 10-5 to 5 × 10-7). Nonetheless, HI was close to 1 for Pb via dust exposure for young urban children, which signifies the risk of non-carcinogenic health problems in studied area. Graphical abstract.

Trace metals in different socioeconomic indoor residential settings, implications for human health via dust exposure.

In this study a number of heavy metals namely chromium (Cr), cadmium (Cd), zinc (Zn), barium (Ba), copper (Cu), manganese (Mn), cobalt (Co), rubidium (Rb), selenium (Se) are studied in the floor and air condition (AC) filter dust collected from urban and rural households of Saudi Arabia. To the best of our knowledge, many of these heavy metals are reported for the very first time in the indoor dust of Saudi Arabia. Studied metals were higher in urban dust than rural except Mn and Rb which were significantly higher (P < 0.05) in rural dust. All metals, except Cd, Zn, and Ba in urban settings, were detected at higher (P < 0.05) levels in AC filter dust than household floor dust from both rural and urban residential settings. Levels of the two dominant metals i.e., Zn and Mn were up to 1600 and 700 µg/g, respectively in studied dust samples. Also associations between heavy metals and a number of different socio-economic parameters were studied which was significant for some trace metals. In literature exposure to many of trace metals are associated with various health problems, therefore health risk assessment for the Saudi population was calculated by incremental lifetime cancer risk (ILCR) and hazardous index (HI) via dust ingestion, inhalation, and dermal contact. The ILCR for all metals was within the tolerable range of reference values of USEPA (1 × 10- 11 to 1 × 10- 4). However, calculated HI for Mn, Cu, Ni, and Zn was more than 1 via dust exposure, which signifies the non-carcinogenic risk. The study highlights the occurrence of toxic metals in the indoor environments of Saudi Arabia and provides baseline data for future studies on these toxic metals in the region.

Reproductive health profile and circumcision of females in the Hali semi-urban region, Saudi Arabia: A community-based cross-sectional survey.

BACKGROUND: Improving the reproductive health of females has be.come the focus of the developmental efforts of many nations. OBJECTIVES: To identify the reproductive health style of married females, and to determine the prevalence and predictors of circumcision among girls aged less than or equal 18 years in Hali semi-urban region. DESIGN: A cross-sectional household survey SETTING: Houses in Hali, Al-Qunfudhah governorate, western Saudi Arabia during 2017. SUBJECTS AND METHODS: A multistage systematic cluster random sampling method was used to select participants. A validated questionnaire was used in interviewing the head of the selected houses. MAIN OUTCOME MEASURES: Reproductive health profile of women, and circumcision of girls. SAMPLE SIZE: 365 households. RESULTS: Reproductive life starts early in the Hali region as 41.4% of women are married at or before 18 years of age. Consanguinity was recorded in 57.0% of houses. The prevalence of grand multiparity (GMP) was 54.7%; it was significantly associated with current maternal age, age at marriage, low educational levels of both parents and husbands with non-professional jobs. Current use of birth control methods was reported by 28.9% of families, and oral contraceptives (OCs) were the commonest method. Contraceptive use was significantly associated with higher educational levels of both parents and with women having professional work. The prevalence of circumcision was 80.3%. Circumcision was most frequent (59.4%) at age 7 years or less, and almost always done by doctors (91.4%). Hemorrhage (2.9%) and fever (2.3%) were the minimal recorded complications. Girls with higher parental education, enough income, no parental consanguinity, and whose mothers married at an older age had slightly lower rates of circumcision, but the difference was without statistical significance. CONCLUSION: The pattern of early female marriage, high consanguinity, GMP, low contraceptive use, and a high frequency of circumcision in girls was apparent in Hali. Public health education and legislative policies are needed. LIMITATIONS: Recall bias may affect the reported frequency of circumcision, and related complications. CONFLICTS OF INTEREST: None.

Currently used organophosphate flame retardants determined in the settled dust of masjids and hotels of Saudi Arabia, a new insight into human health implications of dust exposure.

Indoor settled dust particles are considered as an important source of human exposure to chemicals such as organophosphate flame retardants (PFRs). In recent decades the Kingdom of Saudi Arabia (KSA) has experienced tremendous growth in population, as a result the number of masjids has also increased significantly to provide sufficient space for the public to offer prayers. The hospitality industry in KSA is also expanding to cater for the ever-increasing number of pilgrims visiting the two holy cities of the kingdom. However, limited data are available on the indoor pollution of masjids and hotels. In this study, PFRs were analyzed in the settled dust collected from various hotels and masjids of Jeddah, KSA. Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and tris(1-chloro-2-propyl) phosphate (TCPP) were the major PFRs in masjid (median = 2490 and 2055 ngg-1) and hotel (median = 2360 and 3315 ngg-1) dust, respectively. A public health risk assessment was carried out by determining the incremental lifetime cancer risk (ILCR), and daily exposure via dust ingestion, inhalation, and dermal contact of PFRs. The calculated daily exposure via dust ingestion was well below the reference dose (RfD) values, and also the calculated hazardous quotient (HQ) and carcinogenic risk were well below the risk mark. However, the ILCR for PFRs was below the reference values of USEPA, which suggested that long-term exposure to these chemicals has a limited cause for concern. The study showed that the general public is exposed to PFRs in the studied microenvironments and the major exposure routes are dermal contact and ingestion.

Phthalates and polycyclic aromatic hydrocarbons (PAHs) in the indoor settled carpet dust of mosques, health risk assessment for public.

A number of studies have reported the occurrence of phthalates and polycyclic aromatic hydrocarbons (PAHs) in indoor settled dust from different occupational and residential settings around the world but limited studies are available from public and religious places. In recent decades Kingdom of Saudi Arabia (KSA) has experienced tremendous industrial growth especially in the petroleum industries, and as result environmental issues related with such industries have also increased but scientific data is still scarce to understand the impact on public health. Therefore, the main objective of this study was to report the phthalates and PAHs profile in the settled dust collected from various mosques of Jeddah, an important part of people living in the region, and to evaluate the health risk associated with these chemicals via dust ingestion, inhalation and dermal contact for the general public who attend mosques for prayers. Phenanthrene (500-3000 ng/g), pyrene (40-1220 ng/g), and chrysene (95-4590 ng/g) were the major PAHs and ∑12PAHs concentrations ranged from 2550 to 9150 ng/g. Whereas, DEHP (

Brominated and organophosphate flame retardants in indoor dust of Jeddah, Kingdom of Saudi Arabia: Implications for human exposure.

Different flame retardants (FRs) namely polybrominated diphenyl ethers (PBDEs), emerging brominated/chlorinated flame retardants (Br/Cl FRs), and organophosphate FRs (OPFRs) were analyzed in cars, air conditioner (AC) filters and floor dust of different households from Jeddah, Kingdom of Saudi Arabia (KSA). To the best of our knowledge, this is first study in literature reporting emerging Br/Cl FRs and OPFRs in AC filter dust and also first to report on their occurrence in dust from KSA. Chlorinated alkyl phosphate, penta-BDEs, BDE-209, and decabromodiphenylethane (DBDPE) were the major chemicals in dust samples from all microenvironments. ΣOPFRs occurred at median concentrations (ng/g dust) of 15,400, 10,500, and 3750 in AC filter, car and house floor dust, respectively. For all analyzed chemicals, relatively lower levels were observed in floor dust than car and AC filter dust. The profiles of FRs in car dust were different from AC filter and floor dust, which reflected their wider application as FR and plasticizer in variety of household and commercial products. For toddlers, assuming high dust intake and 95th percentile concentrations, the computed exposure estimation for BDE-99 was higher than RfD values.

Organohalogenated contaminants in type 2 diabetic serum from Jeddah, Saudi Arabia.

Most of the organohalogenated contaminants (OHCs) have high environmental stability and are lipophilic in nature, thus bioaccumulate through the various routes e.g., inhalation, dermal contact and food intake. Human exposure to these OHCs can induce adverse health effects. Studies on the occurrence of OHCs in human samples from Saudi Arabia are scarce. Therefore, this study aimed at providing preliminary insight on the occurrence of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated biphenyl ethers (PBDEs) in diabetic and non-diabetic donors from KSA. Serum samples were collected from type 2 diabetic patients (n = 40) and control donors (n = 20) to study the impact of OHCs on their health. For the first time we studied the difference of Æ©OHCs in type 2 diabetic and control participants. The order of obtained results was Æ©OCPs (35-650 ng/g lw)> Æ©PCBs (15-90 ng/g lw)> Æ©PBDEs (1.5-68 ng/g lw). The major contributors were p,p'-DDE (median 44 ng/g lw), PCB 153 (2.3 ng/g lw), PCB 138 (2.1 ng/g lw), BDE 153 (1.2 ng/g lw) and BDE 47 (0.85 ng/g lw). Exposure to different OHCs between male and female donors was not significantly different (p > 0.05). However, Æ©PCBs and Æ©OHCs were significantly higher (p < 0.05) in diabetic donors than those of control group. We computed significantly positive correlations (p < 0.05) among different OHCs and between OHCs and age factor. The current study highlights the presence of different OHCs in humans from Jeddah, KSA. This is a preliminary study based on small sample size but our results suggested that detailed studies are required to understand the sources of these pollutants and their impact on human health.