Aerosol size distribution and mass concentration measurements in various cities of Pakistan.

During March and April 2010 aerosol inventories from four large cities in Pakistan were assessed in terms of particle size distributions (N), mass (M) concentrations, and particulate matter (PM) concentrations. These M and PM concentrations were obtained for Karachi, Lahore, Rawalpindi, and Peshawar from N concentrations using a native algorithm based on the Grimm model 1.109 dust monitor. The results have confirmed high N, M and PM concentrations in all four cities. They also revealed major contributions to the aerosol concentrations from the re-suspension of road dust, from sea salt aerosols, and from vehicular and industrial emissions. During the study period the 24 hour average PM(10) concentrations for three sites in Karachi were found to be 461 µg m(-3), 270 µg m(-3), and 88 µg m(-3), while the average values for Lahore, Rawalpindi and Peshawar were 198 µg m(-3), 448 µg m(-3), and 540 µg m(-3), respectively. The corresponding 24 hour average PM(2.5) concentrations were 185 µg m(-3), 151 µg m(-3), and 60 µg m(-3) for the three sites in Karachi, and 91 µg m(-3), 140 µg m(-3), and 160 µg m(-3) for Lahore, Rawalpindi and Peshawar, respectively. The low PM(2.5)/PM(10) ratios revealed a high proportion of coarser particles, which are likely to have originated from (a) traffic, (b) other combustion sources, and (c) the re-suspension of road dust. Our calculated 24 hour averaged PM(10) and PM(2.5) concentrations at all sampling points were between 2 and 10 times higher than the maximum PM concentrations recommended by the WHO guidelines. The aerosol samples collected were analyzed for crustal elements (Al, Fe, Si, Mg, Ca) and trace elements (B, Ba, Cr, Cu, K, Na, Mn, Ni, P, Pb, S, Sr, Cd, Ti, Zn and Zr). The averaged concentrations for crustal elements ranged from 1.02 ± 0.76 µg m(-3) for Si at the Sea View location in Karachi to 74.96 ± 7.39 µg m(-3) for Ca in Rawalpindi, and averaged concentrations for trace elements varied from 7.0 ± 0.75 ng m(-3) for B from the SUPARCO location in Karachi to 17.84 ± 0.30 µg m(-3) for Na at the M. A. Jinnah Road location, also in Karachi.

Effect of moisture on the radon exhalation rate from soil, sand and brick samples collected from NWFP and FATA, Pakistan.

A series of experiments were carried out to study the effect of the moisture content on the radon exhalation rate from soil, sand and brick samples that were collected from the North West Frontier Province and Federally Administered Tribal Areas of Pakistan, using CR-39-based radon dosimeters. After processing, samples were prepared by adding 15, 30 and 45% moisture contents (by weight) and were placed in plastic containers. The dosimeters were installed in it at heights of 25 cm above the surface of the samples. These containers were then hermetically sealed and the dosimeters were exposed to radon for 60 to 65 days. After exposure, CR-39 detectors were etched in 25% NaOH at 80 degrees C for 16 h, and track densities were counted. From the measured track densities, exhalation rate was determined using two different approaches. Maximum average radon exhalation rates of 385 +/- 86, 393 +/- 31 and 362 +/- 36 mBq m(-2) h(-1) were observed at 30% moisture content from soil, sand and brick samples, respectively. A slight decrease in exhalation rate was observed in all samples at moisture content of 45%. According to the t-test, change in the exhalation rate as a function of humidity is significant at 95% confidence level.

Radon exhalation rate from the soil, sand and brick samples collected from NWFP and FATA, Pakistan.

In order to characterise the building materials as an indoor radon source, knowledge of the radon exhalation rate from these materials is very important. In this regard, soil, sand and brick samples were collected from different places of the North West Frontier Province (NWFP) and Federally Administered Tribal Areas (FATA), Pakistan. The samples were processed and placed in plastic containers. NRPB radon dosemeters were installed in it at heights of 25 cm above the surface of the samples and containers were then hermetically sealed. After 40-80 d of exposure to radon, CR-39 detectors were removed from the dosemeter holders and etched in 25% NaOH at 80 degrees C for 16 h. From the measured radon concentration values, (222)Rn exhalation rates were determined. Exhalation rate form soil, sand and brick samples was found to vary from 114 +/- 11 to 416 +/- 9 mBq m(-2) h(-1), 205 +/- 16 to 291 +/- 13 mBq m(-2) h(-1) and 245 +/- 12 to 365 +/- 11 mBq m(-2) h(-1), respectively.

Observations of black carbon aerosols characteristics over an urban environment: Radiative forcing and related implications.

With observations of black carbon (BC) aerosol concentrations, optical and radiative properties were obtained over the urban city of Karachi during the period of March 2006-December 2008. BC concentrations were continuously measured using an Aethalometer, while optical and radiative properties were estimated through the Optical Properties of Aerosols and Clouds (OPAC) and Santa Barbra DISORT Atmospheric Radiative Transfer (SBDART) models, respectively. For the study period, the measured BC concentrations were higher during January, February and November, while lower during May, June, July and August. A maximum peak value was observed during January 2007 while the minimum value was observed during June 2006. The Short Wave (SW) BC Aerosol Radiative Forcing (ARF) both at Top of the Atmosphere (ToA) and within ATMOSphere (ATMOS) were positive during all the months, whereas negative SW BC ARF was found at the SurFaCe (SFC). Overall, SW BC ARF was higher during January, February and November, while relatively lower ARF was found during May, June, July and August. Conversely, the Long Wave (LW) BC ARF at ToA and SFC remained positive, whereas within ATMOS it shifted towards positive values (heating effect) during June-August. Finally, the net (SW+LW) BC ARF were found to be positive at ToA and in ATMOS, while negative at SFC. Moreover, a systematic increase in Atmospheric Heating Rate (AHR) was found during October to January. Additionally, we found highest correlation between Absorption Aerosol Optical Depth (AODabs) and SW BC ARF within ATMOS followed by SFC and ToA. Overall, the contribution of BC to the total ARF was found to greater than 84% for the whole observational period while contributing up to 93% during January 2007.

In-Hospital Outcome of Patients with Cardiogenic Shock Complicating Acute Myocardial Infarction: Results from Royal Hospital Percutaneous Coronary Intervention Registry, Oman.

OBJECTIVES: Cardiogenic shock (CS) is still the leading cause of in-hospital mortality in patients presenting with acute myocardial infarction (AMI). The aim of this study was to determine the in-hospital mortality and clinical outcome in AMI patients presenting with CS in a tertiary hospital in Oman. METHODS: This retrospective observational study included patients admitted to the cardiology department between January 2013 and December 2014. A purposive sampling technique was used, and 63 AMI patients with CS admitted to (36.5%) or transferred from a regional hospital (63.5%) were selected for the study. RESULTS: Of 63 patients, 73% (n = 46) were Omani and 27% (n = 17) were expatriates: 79% were male and 21% were female. The mean age of patients was 60±12 years. The highest incidence of CS (30%) was observed in the 51-60 year age group. Diabetes mellitus (43%) and hypertension (40%) were the predominant risk factors. Ninety-two percent of patients had ST-elevation MI, 58.7% patients were thrombolysed, and 8% had non-ST-elevation MI. Three-quarters (75%) of CS patients had severe left ventricular systolic dysfunction (defined as ejection fraction <30%). Coronary angiogram showed single vessel disease in 17%, double vessel disease in 40%, and triple vessel disease in 32% and left main disease in 11%. The majority of the patients (93.6%) underwent percutaneous coronary intervention (PCI), among them 23 (36.5%) underwent primary PCI. In-hospital mortality was 52.4% in this study. CONCLUSIONS: CS in AMI patients presenting to a tertiary hospital in Oman have high in-hospital mortality despite the majority undergoing PCI. Even though the in-hospital mortality is comparable to other studies and registries, there is an urgent need to determine the causes and find any remedies to provide better care for such patients, specifically concentrating on the early transfer of patients from regional hospitals for early PCI.

2015 Oman Heart Association guidelines for the management of hypertension : practical recommendations from the Oman Heart Association (OHA).

Hypertension (HTN) is a major independent risk factor for the development of stroke, coronary artery disease (CAD), peripheral arterial disease (PAD), heart failure (HF) and chronic kidney disease (CKD). HTN is a growing public health problem in Oman, almost certainly the most prevalent modifiable risk factor for cardiovascular disease (CVD). The risk of CVD in patients with HTN can be greatly reduced with lifestyle modifications and effective antihypertensive therapy. Randomized trials have shown that blood pressure (BP) lowering produces rapid reductions in CV risk. Several studies have shown that the majority of the hypertensive patients remain uncontrolled. It is well established that the observed poor control of the disease is not only related to poor adherence to medications, but also to limited awareness and adherence to evidence-based management of hypertension among physicians. Several guidelines for the management of patients with hypertension have been published. However, the aim of this document is to provide the busy physicians in Oman with more concise and direct approach towards implementing these guidelines into clinical practice.

2014 Oman Heart Association protocol for the management of acute atrial fibrillation.

Although atrial fibrillation (AF) is the most common cardiac arrhythmia, there is variation in practice with regard to the management of acute AF among the hospitals and even within the same hospital in Oman. This variation likely reflects a lack of high-quality evidence. Standard guidelines and textbooks do not offer clear evidence-based direction for physicians to guide the management of acute AF. Particularly controversial is the issue of using rhythm control or rate control. This stimulated Oman Heart Association (OHA) to issue a simplified protocol for the management of acute AF to be applied by the entire cardiac caregivers all over the country. The priorities for acute management of AF include stabilizing the patient's hemodynamic status, symptom control, treatment of the underlying and precipitating cause, and more importantly protecting the brain.

Clinical Pathways for Non-ST Elevation Acute Coronary Syndrome in Oman: An Oman Heart Association Protocol for Hospital Quality Improvement Initiative.

In 2012, Oman Heart Association (OHA) published its own guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction, the aim was not to be comprehensive but rather simplified and practical in order to reduce the gap between the long comprehensive guidelines and our actual practice. However, we still feel that the busy registrars and residents need simpler and direct clinical pathways or protocol to be used in the emergency departments, coronary care units and in the wards. Clinical pathways are now one of the main tools used to manage the quality in healthcare concerning the standardization of care processes. It has been shown that their implementation reduces the variability in clinical practice and improves outcomes in acute care.

Characterization and source apportionment of ambient air particulate matter (PM2.5) in Karachi.

Concentrations and source apportionment of PM(2.5) monitored at an urban residential site in Karachi Metropolitan, Pakistan have been reported in this paper. PM(2.5) aerosol samples were collected on alternative days (three times per week) for 24-hrs duration on Zefluor(TM) filter papers using Thermo-Electron Corporation Reference Ambient Air Sampler (RAAS). A total of 402 samples were collected from January 2006 to January 2008. According to results high PM(2.5) loads were observed in post monsoon months that is about 2 times than those observed in the summer and monsoon seasons in the yearlong measurements. The collected samples were analyzed using ICP-MS for trace metal concentration. Source apportionment was performed on PM samples using Positive Matrix Factorization (PMF) model. The results derived from PMF model indicated five (05) major contributors to PM(2.5) in Karachi which were: soil/road dust, industrial emissions, vehicular emissions, sea salt originated from Arabian Sea and secondary aerosols.

Indoor radon concentration measurement in the dwellings of district Poonch (Azad Kashmir), Pakistan.

The present study deals with measurement of indoor radon concentrations in dwellings of the district Poonch of the state of Azad Jammu and Kashmir, Pakistan. In this context, CR-39-based box-type radon detectors were installed in drawing rooms and bedrooms of 80 selected houses and were exposed to indoor radon for 3 months. After exposure, the CR-39 detectors were etched for 9 h in 6 mol NaOH at 70 degrees C and the observed track densities were related to radon concentrations. Measured indoor radon concentrations in the studied area ranged from 27 +/- 6 to 169 +/- 4, 29 +/- 6 to 196 +/- 4 and 31 +/- 5 to 142 +/- 2 Bq m(-3) in the drawing rooms and 74 +/- 5 to 172 +/- 3, 32 +/- 6 to 191 +/- 4 and 27 +/- 5 to 155 +/- 2 Bq m(-3) in bedrooms of the Abbaspur, Hajira and Rawalakot regions of the district Poonch, respectively; whereas weighted average radon concentration ranged from 93 +/- 6 to 159 +/- 4, 33 +/- 5 to 118 +/- 3 and 31 +/- 6 to 155 +/- 5 Bq m(-3) in the dwellings of Abbaspur, Hajira and Rawalakot, respectively. Estimated doses due to the indoor radon ranged from 2.35 +/- 0.15 to 4.00 +/- 0.10, 0.83 +/- 0.08 to 2.98 +/- 0.08 and 0.78 +/- 0.15 to 3.91 +/- 0.13 mSv y(-1) for Abbaspur, Rawalakot and Hajira, respectively. Comparing the current indoor radon results with those of the Health Protection Agency UK and US EPA (i.e. 200 and 148 Bq m(-3)) limits, majority of the houses surveyed in the present study are within the safe limits.

Assessment of indoor radon doses received by the students in the Azad Kashmir schools, Pakistan.

Several epidemiological studies conducted on thousands of underground miners suggest that long- term exposure to high radon concentration can increase the risk of lung cancer. Keeping in view the importance of the subject, numerous studies throughout the world have been carried out to measure indoor radon concentration and its resulting doses at occupational and non-occupational sites. The purpose of the current study was to measure indoor radon concentration and its resulting doses received by the students of Azad Kashmir government schools. For this purpose, CR-39 radon detectors were installed in 80 carefully selected schools. The detectors were placed at a height of 3-5 ft. (depending upon average height of students in particular class) from the ground. After exposure of 90 d detectors were etched for 9 h in 6 M NaOH at 70°C and the observed track densities were related to radon concentrations. The measured indoor radon concentration ranged from 22 ± 9 to 228 ± 3 Bq m(-3) with a mean value of 78 ± 5 Bq m(-3). Based on the measured indoor radon data, the annual effective doses were found to vary from 0.55 ± 0.04 to 0.71 ± 0.03 mSv y(-1). The overall mean effective dose for the studied area was found to be 0.63 ± 0.04 mSv y(-1). Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces.

Natural radioactivity measurements in Pakistan--an overview.

Humans have always been exposed throughout their period of existence to naturally occurring ionising radiation. Specifically, naturally occurring radionuclides are present in variable amounts in our environment. To assess radiological health hazards, naturally occurring radionuclides are being measured in soil, sand, marble, bricks etc throughout the world. In this regard, extensive data have been reported for Pakistan, which have been compiled and reviewed in this article. The majority of the reported articles are about monitoring of the radiological health hazards of naturally occurring radionuclides. In a few articles, use of the radionuclides has been reported for the exploration of uranium and thorium deposits. Most of the reported data have been obtained using a high purity germanium detector or a sodium iodide detector.

A review of radon measurement studies in Pakistan.

Radon is being extensively measured all over the world due to its hazardous health effects as well as for different geological applications. In this regard, considerable studies have been conducted by different research groups in Pakistan. However, these studies are scattered and need to be combined/listed somewhere for future studies of radon in Pakistan. In this article, all the studies concerning radon measurements have been reviewed. The main emphasis is on different methods used in the measurement of radon. A minimum value of 5 Bq m(-3) has been reported for a centrally air conditioned room and a maximum value of 782 +/- 125 Bq m(-3) has been observed in coal mines of Khushab, Punjab.