June, 2013

 

Abstract According to a preliminary report on mercury inventory, published in 2000, the point sources of mercury releases and emissions in Pakistan are a chlor-alkali plant, light products manufacturing units, dental clinics, incinerators and other coal based primary or secondary unit operations. Based on this reported preliminary data, the estimated maximum and minimum emission and transfer of mercury in the country is about 36,900 and 10,800 kg per year, respectively. At present, there is no mercury specific legislation in the country. However, development of a mercury management national action plan is in the making.

In the present study, mercury levels in and around mercury releasing sources and in open air are being examined, to identify "Mercury Hot Spots" in some cities of Pakistan, namely Peshawar, Rawalpindi-Islamabad and Lahore. The selected sites for measuring air mercury levels were chlor-alkali plant (1), light products manufacturing companies (2), dental clinics, teaching hospital and dental colleges (36). The selected sampling points at these sites were treatment sections, adjacent corridors and open air.

The high precision RA-915+ mercury analyzer was used to measure mercury levels in air at the selected sites. Few climatic parameters, like temperature, humidity and wind speed were measured with Kestrel® 4500 and wind direction with the help of a Field Compass, whereas geographical coordinates were taken with Garmin-eTrexGPS. Two separate questionnaires, one each for the dental and industrial sites, were developed for collecting the background relevant information regarding mercury use, waste and disposal at each sampling site. For discussion of the results, ASTDR MRL, 200 ng/m3, US EPA (RfC) 300 ng/m3and WHO/ACGIH, 25,000 ng/m3 have been referred

Among all the visited/monitored dental sites in Lahore, Peshawar, Rawalpindi & Islamabad, eleven (11) sites were observed to be most contaminated, at the time of the visit. Among dental sites mercury contamination of air was found to be generally in the increasing order operative section > corridor > open air and teaching hospitals/dental colleges > general hospitals > private clinics. Monitoring data indicated high mercury levels, of air in and around the surroundings of the visited industrial units. The study also showed, the unawareness to the mercury handling, mishandling of the mercury/mercury amalgam, mercury containing waste, improper and inadequate ventilation system and lack of awareness regarding health hazards of mercury, being the main reasons for the observed elevated levels of mercury in air at some of the visited sites.

The data/results, findings and recommendations for releases/emissions control and phasing out of mercury use in the country is planned to be shared with all stakeholders, including policy makers and government officials, for appropriate policy interventions and an action plan to safeguard public health, specially of children and for the protection of the environment.  

Details of the above investigations, results achieved and recommendations made are described and discussed in this report.