1 Estimation of PM 10 Health Impacts on Human within Urban Areas of Makkah city , KSA

1 The Custodian of the Two Holy Mosques Institute for Hajj and Umrah Research, Umm Al -Qura University, Makkah, Saudi Arabia.  2 Air pollution Department, Nat ional Research Center, Cairo, Egypt.  *Corresponding author: ateffathy2006@yahoo.com Mob.: 00201151143456 ; ORCID: 0000-0002-2930-0168 Abstract The current study aimed to: i) Monitor levels of PM10, at Shebika, Haram, Masfala, Azizia, Awali and Mina in Makkah city, KSA during the period of 01 Shawwal 1436H – 27 Rabi Al-Awwal 1437H, by using LVS instruments; and; 2) assess health risk (non-cancer and cancer risks) on humans (children and adult) exposed to PM10 in ambient air of Makkah city. The results showed that: the high PM10 levels were found in Haram site, while the lower levels were found in Awali site. These levels were lower than that set for PM 10 by PME (Daily limit of 340 μg/m 3 ). Vehicles emissions and constructions sources may be the main source of PM 10 levels in Makkah city. The human health risk assessments showed that: the daily exposure doses of PM 10 were ranked in the order: Ding > Ddermal > Dinh for children and adult in Makkah city. Ingestion of PM10 particles was the main exposure pathway for both children and adults. The HIs and cancer risk values were within the safe level, indicating that (non-carcinogenic and carcinogenic) risks for humans exposed to PM 10 in Makkah city were negligible.


Introduction
Respirable particulate matter (PM 10 ) was particles with a diameter ≤ 10.PM 10 was a complex mixture of dust, salt, acids, organic matter and metals; which varied in levels, composition and sources (Pope and Dockey, 2006).Human Exposed to PM 10 might be affected by definite (cancer and non cancer) risks (Hnizdo andVallyathan, 2003, Davies, 2012).The health impact of children and adults exposed to PM 10 in ambient air were reported in several studies like: ATS, 1997;Batterman et al., 2011;Thabethe et al., 2014.PM 10 in ambient air were easily enter the human body via three primary pathways: inhalation (through mouth and nose, which may reach the alveolar in the lung), ingestion (through mouth and nose), and Dermal absorption of particles adhered to exposed skin contac t (US EPA, 1989;2004;Darquenne et al., 2000;Ferreira and De Miguel, 2005;Ahmed and Ishiga, 2006;Zheng et al., 2010aZheng et al., , 2010b;;Lu et al., 2014;Xu et al., 2015).The levels and health risks of PM 10 exposed to humans were evaluated in different previous s tudies such as: Apeagyei et al., 2011;Tang et al., 2013;Kexin et al., 2015.However, the most previous studies focused on PM 10 in capital cities or mega-cities, which characterized by traffic density and over population.There was lake in that studies in Makkah city and the other cities in Kingdom Saudi Arabia (KSA).The major sources of PM 10 in ambient air of Makkah city include: vehicles emissions, construction; paved roads; unpaved roads , power plant emissions and windblown dust from open lands.Given these air pollution sources, it was deemed necessary to estimate the likely human health risks posed by PM 10 to the residents of Makkah city, an activity never done before for this geographic region, for future planning and management of air pollution in the area.The main objectives of this study were to: i) Monitor levels of PM 10 , mainly emitted in urban sites at Makkah city, KSA; and 2) evaluate health risk (non-cancer and cancer risks) associated with PM 10 exposure for children and adult in Makkah city.

Study area and sampling sites description
The current study; PM 10 samples were collected fro m ambient air at 6 sites located in Makkah city, KSA (Fig. 1).Makkah city is located 70 km inland fro m Jeddah in a narrow valley at a height of 277 m above sea level.Makkah city lies in a corridor between mountains.This mountainous location has defined the contemporary expansion of the city.The total area of Makkah stands over 1,200 km 2 .Its resident populations in 2014 were roughly (1,919,909 people ≈ 2 million), although visitors (pilgrims) more than 6,000,000 people every year during the hajj and Umraa seasons (Statistical Yearbook, 2014).The brief descriptions of the sampling sites were given in Table 1.

Aziziah
 Lower south squares of the Holy Mosque. Likewise a busy location and had a high traffic density during sampling period.

Awali
 New area.
 Quiet residential area famous by villas and some facilit ies such as petrol stations and supermarkets. Near to Taif Road and the mountains.

Mi na
 Desert area about 5 km east of Makkah. The area is known for its important role for pilg rims, where many pilgrims stay on a temporary basis during hajj.

Sampling Method
LVS (Low Vo lu me Samp ler) were used to collect respirable particulate matter (PM 10 ) in 6 sites.Samples were collected weekly during the period from 1 Shawwal 1436 AH -27 Rabi al-A wwal 1437 AH, collecting a total o f 30 samp les, the sampling time was 24 h.LVS manufactured by the German Beko (Beco R300), wh ich calibrated before device used.LVS were use nitrate cellu lose filters with size of 0.45 microns for dust least 10 micro meters (Fig. 2).Filtration method was used for estimating the total concentration of PM 10 .Where filter paper is weighted in the laboratory before sampling, and then transported carefully to sampling holder.After sampling the loaded filter is carefully transfer to the laboratory, where it is weighed to constant weight.The difference in weight before and after sampling is equal to weight of PM 10 collected.PM 10 concentrations can be calculating by using the sample air volu mes and the weight of PM 10 collected and expressed as µg/m 3 (JIS, 1992).1989; 2004).Exposure was expressed in terms of daily dose (mg/kg.day).The exposure factors for these models were shown in Table 2.

Risk Assessment
Hazard quotients (HQ) for non-carcinogenic effects were applied to each exposure pathway in the analysis to evaluate the non-carcinogenic risks due to PM 10 in ambient air of Makkah city, KSA.The daily exposure doses calculated for each exposure pathway were subsequently divided by the reference dose of PM 10 (RfD = 1.1x10 -2 mg/kg.day,Zou et al., 2009) to yield a hazard quotients (HQs) according to equation 5 (US EPA, 1989, 1996): The hazard index (HI) was then the sum of HQs and was used to represent the total potential noncarcinogenic risks of PM 10 in ambient air of Makkah city, KSA.If (HI < 1), there was no significant risk of non-carcinogenic effects.If (HI > 1), then there was a chance that non-carcinogenic effects may occur (US EPA, 1989; US EPA, 2001;Ferreira and Miguel, 2005;Lim et al., 2008;Zheng et al., 2010a,b;Xu et al., 2015).In the case of carcinogenic risks, the dose was multiplied by the slope factor of PM 10 (SF = 2 x 10 -6 (mg/kg.day) - , Vallero, 2014) to produce a level of cancer risk according to equation 6: R = ADD x S F …………………….Eq.5 Carcinogenic risk is the probability of an individual developing any type of cancer fro m lifetime exposure to carcinogenic hazards.EPA considered cancer risks between 10 -6 (i.e., 1 in 1,000,000 people) and 10 -4 (i.e., 1 in 10,000 people) to be generally acceptable (US EPA, 1991b).Cancer risks higher than 10 -4 might not be considered sufficiently protective and many warrant remed ial action ( Lim et al., 2008;US EPA, 2009a).

Results and Discussions PM 10 concentrations
The daily average respirab le particu late matter (PM 10 ) concentrations in amb ient air of 6 sampling sites in Makkah city were measured during period from 1 Shawwal 1436 AH -27 Rabi al-A wwal 1437 AH (as shown in Fig. 3).LVS instruments was used to collect samples.The PM 10 concentrations measured were generally higher in Haram site (343 µg/ m 3 ) than the PM 10 concentrations measured in Awali site (64 µg/ m 3 ).These concentrations were lower than the PME Daily limit of 340 µg/ m 3 on most of the days, except in Haram site (PM E, 2001).Which means that even if the population of Makkah was exposed to that levels of PM 10 , negative health impacts may be unlikely, as concentrations were below the daily average limit of PME, although some individuals may still be sensitive to relatively low PM 10 concentrations (WHO, 2006).The current study attributed concentrations obtained of PM 10 to greatest efforts exerted by the Govern ment of the Kingdom o f Saudi Arab ia represented by the executive authorities in the city of Makkah Al Mukarramah (such as the Holy City, the Holy City Secretariat and the General Presidency of the Holy Mosque) in providing clean air and environment free fro m harmful air pollutants to take care pilgrims.Moreover, Presence of sprayers located in the squares, which he lps to deposit and reduce the dust suspended in the air.Furthermore, The presence of hotels surrounding the areas, which act as windbreakers loaded with airborne dust, and helps to re-establish and reduce its concentrations in the squares.In addition, Ra infall on the city of Mecca during the measurement period, which helped to purify amb ient air and deposit dust.In Makkah the major factor responsible for the high emission of PM 10 is probably the higher number of visitors to the Holy Mosque during Hajj season (Zul-Qaadah -Zul-Hijjah), that leads to higher traffic flo w on roads around the Holy Mosque in Makkah city (elevated vehicle emission levels ).Table 3 showed comparison between levels of PM 10 in the current study and levels found in other cities around the world.5).In the current study, the daily doses of PM 10 were ranked in the order: D ing > D dermal > D inh for children and adult for non-cancer risk and cancer risk at all sampling sites.

Non-carcinogenic risk assessment
The results of the hazard quotient (HQ) values of different exposure pathways (D ing , D inh , and D dermal ), hazard index (HI) for both children and adults in sampling sites at Makkah city were calculated in Table 6.Among three different exposure pathways, the HQ ing values were the highest and contributed the most to HIs for both children and adults at all sites, indicating that ingestion of PM 10 appears to be the most threatening exposure way to human health in Makkah city (Fig. 4).The HQs for all studied sites were ranked in the order: HQ ing > HQ dermal > HQ inh for children and adult.Results also showed that the inhalation of PM 10 had the lowest contribution to health risks for children and adults, indicating that the non-cancer risks posed by the inhalation of PM 10 might be negligible compared with ingestion and dermal contact.Similar results were obtained by previous studies (Ferreira and De Miguel, 2005;Zheng et al., 2010a;OSHA, 2013).Additionally, children were found to experience higher health risks through ingestion compared with adults.The values of HQ ing for children were 9.3 times higher than those for adults.This result may be partially attributed to the special behavior patterns of children, particularly frequent hand-to-mouth contact.Similar results were obtained by (Kexin et al., 2015) where they reported The values of HQ ing for children were 9.33 times higher than those for adults.The HIs for all studied sites were ranked in the order: HI ing > HI dermal > HI inh for children and adult.
(Table 6).The integrated HI values in Makkah city were 8E-04 for children and 9E-05 for adults, indicating children are likely to experience significantly higher non -cancer risks.The HI values for all sampling sites in this study were within the safe level (HI < 1) , this results indicated that there was no significant risk of non-carcinogenic to children and adults from exposure to PM 10 levels in Makkah city.Similar results were obtained by previous studies (EPA, 1989;USEPA, 2001;Ferreira and Miguel, 2005;Lim et al., 2008;Zheng et al., 2010a,b;Xu et al., 2015).

Carcinogenic risk assessment
The results of the cancer risks according to different exposure pathways (D ing , D inh , and D dermal ), for both children and adults in sampling sites at Makkah city were presented in Table 7.The R ing values were the highest and contributed the most to cancer risk for both children and adults at all sites, indicating that ingestion of PM 10 appears to be the most exposure way to human cancer risk in Makkah city (Fig. 5).The cancer risk for all sampling sites were ranked in the order: R ing > R dermal > R inh for children and adult.Results also showed that the inhalation of PM 10 had the lowest contribution to health risks for children and adults, indicating that the cancer risks posed by the inhalation of PM 10 might be negligible compared with ingestion and dermal contact.Similar results were obtained by previous studies (Ferreira and De Miguel, 2005;Zheng et al., 2010a).The cancer risk values in Makkah city were 1E-12 (i.e., 1 in 1,000,000,000,000 people) for children and 6E-13 (i.e., 6 in 10,000,000,000,000 people) for adults, indicating children and likely to experience significantly negligible cancer risks.The cancer risk values for all sampling sites in this study were within the safe level (10 -6 (i.e.) 1 in 1,000,000 people and 10 -4 (i.e.) 1 in 10,000 people; US EPA, 1991b

Conclusions
A total of 30 respirable particulate matter (PM 10 ) samples were collected from 6 sites (Shebika, Haram, Masfala, Azizia, Awali and Mina) in Makkah city, KSA during the period of 01 Shawwal 1436H -27 Rabi Al-Awwal 1437H, by using LVS instruments .The concentration of PM 10 were analyzed.Human health risks for PM 10 were assessed using health risk assessment model.Results showed that: i) The maximum PM 10 concentrations were found in Haram site (343 µg/m 3 ) and the minimum in Awali site (64 µg/m 3 ).These concentrations were lower than the PME Daily limit of 340 µg/m 3 , except in Haram site.ii)Vehicles emissions and constructions sources may contribute mostly to the levels of PM 10 in Makkah city.iii) The health risks analysis showed that children and adult were at nearly equal risk from exposed to the same levels of PM 10 for the same duration.The daily exposure doses of PM 10 were ranked in the order: D ing > D dermal > D inh for children and adult for non-cancer risk and cancer risk at all sampling sites.Ingestion was the dominant exposure pathway for both children and adults.The inhalation of PM 10 had the lowest contribution to health risks for children and adults, indicating that the inhalation of PM 10 might be negligible compared with ingestion and dermal contact.The values of HQ ing for children were 9.3 times higher than those for adults.The HIs values for all sampling sites were within the safe level (HI < 1).The cancer risk values for all sampling sites were within the safe level (10 -6 (i.e.) 1 in 1,000,000 people and 10 -4 (i.e.) 1 in 10,000 people).The cancer risk values for PM 10 in Makkah city were within the acceptable range, implying negligible carcinogenic risk.More studies should be conducted to assess the indoor exposure to air pollution focussing on the more vulnerable groups such as infants, students, wo men, and the elderly and those suffering fro m other respiratory and cardiovascular diseases.

Figure 1 :Haram
Figure 1: Sampling sites in Makkah city, Ki ng dom of Saudi Arabia (KS A).Table 1: Sampling sites description Site Name Brief descripti on

Fig. 2 :
Fig. 2: Low Vol ume Sampler (LVS) and PM 10 hol der.Health Risk Assessment The Daily Expos ure dose (D) In the current study, the health risk assessment model developed by the Environmental Protection Agency of the United States (US EPA) was used to evaluate the health risks of PM 10 in Makkah city, KSA.Peoples in Makkah city (local residents and pilgrims) were divided into adults and children.Human were exposed to PM 10 in ambient air via three primary pathways: i) Inhalation of suspended particles through mouth and nose (D inh ); ii) Ingestion of dust particles through mouth (D ing ); and iii) Dermal absorption of PM 10 particles adhered to exposed skin (D dermal ).The daily exposure dose (D) of PM 10 calculated separately for each exposure pathway according to equations (1, 2, and 3) (US EPA,1989; 2004).Exposure was expressed in terms of daily dose (mg/kg.day).The exposure factors for these models were shown in Table2.

Figure 4 :
Figure 4: Non-carcinogenic risk distri bution of di fferent exposure ways for chil dren and adults in Makkah.

Figure 5 :
Figure 5: Cancer risks distribution of different exposure ways for chil dren and adults in Makkah.
).This results indicated that cancer risk values for Makkah city in this study were within the acceptable range, Preprints (www.