Environ Monit Assess (2015) 187: 145 DOI 10.1007/s10661-015-4311-2
Use of mercury-based medical equipments and mercury content in effluents of tertiary care hospitals in India Sharda Shah Peshin & Nabanita Halder & Chandrababu Jathikarta & Yogendra Kumar Gupta
Received: 7 August 2014 / Accepted: 3 November 2014 / Published online: 26 February 2015 # Springer International Publishing Switzerland 2015
Abstract Environmental pollution due to mercury has raised serious concern over the last few decades. Various anthropogenic sources including the health sector play a vital role in increasing the mercury load on the environment. Mercury poses an important health issue because of its indiscriminate disposal into the environment. There are numerous mercury-containing devices being used in the health-care setup. The objective of the study was to obtain information on the procurement and consumption of mercury-containing items in the current year, the methods adopted for disposal and the contamination of the hospital effluents with mercury. A questionnaire-based study was conducted in government and corporate hospitals from different states of India, for the quantitative assessment of use of mercury-based items in tertiary care hospitals in India (n = 113). The results showed that mercurycontaining items are still being used in India. The most common method adopted for disposal was collection in plastic bags and labeling them as hazardous waste. The Electronic supplementary material The online version of this article (doi:10.1007/s10661-015-4311-2) contains supplementary material, which is available to authorized users. S. S. Peshin : N. Halder : C. Jathikarta : Y. K. Gupta (*) Department of Pharmacology, All India Institute of Medical Sciences, New Delhi 110029, India e-mail: [email protected] S. S. Peshin e-mail: [email protected] C. Jathikarta Hazardous Waste Management Division, Central Pollution Control Board, Ministry of Environment & Forests (Government of India), East Arjun Nagar, Delhi 110032, India
hospital effluents contained mercury below the permissible limits. In view of the environmental pollution due to mercury and its adverse impact on health, efforts by the government are on for phasing out mercury-containing equipments from the health-care setup in India. Keywords Hospital effluents . Medical equipments . Mercury
Introduction Mercury is ubiquitously present as a pollutant in environment. It occurs naturally in the earth’s crust and is distributed throughout the environment through natural processes like volcanic eruptions, erosion of mineral deposits, and weathering of rocks. Various anthropogenic activities including combustion of coal and petroleum products, cement and chlor-alkali production, metallurgical activities, and medical waste incineration cause environmental pollution. Once released from any source, it eventually makes its way into the environment. The complex and long-range movements of mercury make it a global pollutant (Clarkson 2002). Mercury exists in three forms in the environment— elemental, inorganic, and organic. The three basic steps involved in the cycling of mercury in environment include (i) release of the mercury from its sources, (ii) transport and deposition, and (iii) biological conversion and uptake by living organisms. Elemental mercury is a liquid that vaporizes at ambient temperature and pressure. Mercury entering the ecosystem
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can cycle indefinitely. It is deposited in soil and water bodies, where microorganisms convert elemental mercury into highly toxic methyl mercury, which is taken up by aquatic plants and animals. Methyl mercury accumulates in organisms (bioaccumulation), and the concentrations increase up at each level of the food chain (biomagnification). Bioaccumulation and biomagnification effects result in mercury levels of toxicological concern with serious implications, especially for human beings (Clarkson 2002). In the last few years, there has been an increasing global concern about the mercury pollution and its impact over health. The adverse health effects mainly depend on the chemical form, route, dose, duration of exposure, and health and age of the person exposed. Elemental mercury is absorbed through inhalation affecting mainly the respiratory system. The primary tissues of distribution are the central nervous system and kidneys. Inorganic mercury mainly targets the kidneys and gastrointestinal system, whereas organic mercury especially methyl mercury affects the central nervous system. It is a neurotoxin affecting all age groups. The developing fetus especially in mothers consuming fish may be more vulnerable to methyl mercury than the adults. (www.epa.gov; Murata et al. 2011). The adverse effects of mercury on human health even when present in traces are well reported (Zahir et al. 2005). The health sector plays a significant role in the emission of mercury in environment due to huge demand in various instruments and thus contributes to environmental pollution in view of usage, breakage of mercury-containing products, and spills. The most widely used form in health-care devices is elemental mercury. The common mercurycontaining devices used in health-care sector include thermometers, sphygmomanometers, dental amalgams, gastrointestinal tubes, preservatives, fixatives, medical batteries, compact fluorescent lamps (CFLs), operation theatre (OT) bulbs, thermostats, etc. (Shaner 1997; Clarkson et al. 2003). Mercury-containing products upon breakage release mercury into the environment if discarded improperly (Pastore et al. 2007). Since mercury vaporizes at room temperature, the spills can also be a source of acute inhalation besides contaminating the environment. Leaked mercury from various products often ends up in water and soil due to improper disposal. Medical waste incineration further contributes to pollution. Hence, inadequate or improper disposal of mercury-containing waste pollutes the environment consequently endangering wildlife and human health. The problem of mercury pollution in health-care sector is being realized in India with focus on strategies on source reduction, waste minimization, safe storage
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and disposal, etc. (www.tnpcb.gov.in). India is also participating in an initiative aimed at phasing out mercurycontaining fever thermometers and sphygmomanometers by at least 70 % and switching over to alternatives by 2017 (www.mercuryfreehealthcare.org). Although the use of mercury in the health-care facilities in India has declined over the years, mercury-based equipments are still being used (Kumari et al. 2011). Due to the improper handling, disposal, and waste management of mercury-containing items, the hospitals are one of the major contributors of environmental pollution. With this background, the present questionnairebased study was designed to assess the current status of the extent of use of mercury-containing equipment and methods of disposal adopted by various hospitals in India. In addition, analysis of mercury levels in the final effluent of some tertiary care hospitals in the states of Delhi, Haryana, and Uttar Pradesh were also undertaken, to check contamination of hospital effluents with mercury due to improper disposal.
Material and methods
Quantitative estimation of the mercury items A questionnaire was designed to obtain information on procurement and consumption of mercury-containing items during the year 2009–2010 and the methods adopted for disposal by various tertiary care hospitals. It was sent to different hospitals in India (n=113), and the responses were tabulated.
Analysis of hospital effluent samples to estimate mercury levels Thirteen hospitals were selected for effluent analysis in the states of Delhi, Uttar Pradesh, and Haryana (govt. sector=47 %, corporate sector=53 %) in consultation with the Central Pollution Control Board, Government of India. The questionnaire-based survey on assessment of awareness about the environmental pollution due to mercury had already been carried out in these hospitals (Halder et al. 2013).
Environ Monit Assess (2015) 187: 145
Collection of effluent samples Effluent samples (1000 mL) were collected in ambercolored bottles rinsed with nitric acid solution in water (1:1). The samples were preserved by adding 2 ml of acidified potassium dichromate (20 % w/v K2Cr2O7 in HNO3, 1:1) and stored in a refrigerator at 4 °C.
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through the vapor generation system, carries elemental mercury from solution and then passes through the absorption cell. A standard curve of mercuric chloride was plotted. The absorbance of the test samples was recorded, and the concentration of mercury was calculated using the standard curve.
Results Digestion of effluent samples The digestion of the effluent samples (100 mL) was carried out in a biological oxygen demand (BOD) bottle by treatment with concentrated sulfuric acid (5 mL), nitric acid (2.5 mL), and potassium permanganate (5 %, 15 ml), and the mixture was allowed to stand for 15 min. Then potassium per sulfate (5 %, 8 ml) was added, bottle stoppered, and mixture heated on a water bath for 2 h at 95 °C. Post-cooling the mixture at room temperature, sodium chloride and hydroxylamine hydrochloride (120 g NaCl+120 g NH2OH·HCl in 1 L of distilled water, 5–6 mL) was added. Finally, 5 mL of stannous chloride (20 % SnCl2 in 10 % HCl) was added to each sample before analysis (APHA, 2005).
Mercury analysis Mercury levels in effluent samples were estimated using a Mercury Analyser (MA5840, Electronic Corporation of India, Hyderabad). Analysis is based on the cold vapor technique where the mercury vapor (atoms) absorbs resonance radiation at 253.7 nm. The carrier gas (air) bubbles Fig. 1 Use of mercurycontaining items in different hospitals in 2009–2010
Quantitative estimation of the mercury items The questionnaire-based proforma was sent to various hospitals (n=113, govt. sector=63.7 %, corporate sector=36.2 %). Only 45 hospitals (39 %) responded to the queries among which 41 (91 %) hospitals indicated use of mercury-containing items. While analyzing the data obtained from 41 hospitals for the overall use of mercury containing items, the results showed 32 % hospitals had reduced the use of these items, while there was an increase in use of these items in 22 % hospitals. However, 14 % of the hospitals indicated no change in use of mercury-containing items as compared to the previous year. Moreover, 32 % of hospitals did not respond to this question (Fig. 1). The results have shown that sphygmomanometers and thermometers (95 and 85 %) are still being used by hospitals. Mercury-containing compact fluorescent lamps and operation theatre bulbs were used by 82 and 65 % hospitals. However, only 21 % hospitals used esophageal dilators. Dental amalgam was found to be used by 31 % hospitals (Fig. 2).
145 Page 4 of 8 Fig. 2 Use of different mercurycontaining items in hospitals (%)
Environ Monit Assess (2015) 187: 145 TH: Thermometer SP : Sphygmomanometer ED :Esophageal dilator CFL : Compact fluorescent lamps OTB : Operaon theatre bulbs DA: Dental amalgam
100 90 80 70 60 50 40 30 20 10
0 TH
SP
ED
CFL
OTB
DA
Mercury-containing items
Comparison of the trend of procurement of individual mercury-containing items by various hospitals has shown that an attempt was made by27 and 34 % hospitals towards less procurement of thermometers and sphygmomanometers, respectively. However, at the same time, increased procurement of thermometers (27 %) and sphygmomanometers (22 %) was also reported by hospitals. There was observed an increase in the procurement of compact fluorescent lamps by 35 % and operation theatre bulbs by
Fig. 3 Trend in procurement of individual mercury-containing items by hospitals as compared to the previous year
22 % hospitals. In a fraction of hospitals, the procurement status remained the same as the previous year (Fig. 3). Various methods were used for the disposal of mercurycontaining waste, and it was observed that collecting the mercury waste in separate plastic bags, sealing, and disposal was a common practice followed by majority of hospitals (35 %). Auctioning as a waste was done by 22 % of the hospitals. Only 15 % hospitals incinerated the mercury-containing waste, and 10 % got it disposed off
Environ Monit Assess (2015) 187: 145
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Fig. 4 Methods of mercury waste disposal by various hospitals (%)
by the Municipal Corporation. However, 17 % of the hospitals used other methods for disposal (Fig. 4).
Mercury estimation in hospital effluents
existing facility was not in a working condition. Analysis of the results for effluents of the hospitals surveyed (n=13, govt. sector=47 %, corporate sector=53 %), showed that mercury levels in the hospitals were below the permissible limit for public sewers. Mercury was not traceable in the effluents of only two corporate hospitals (Table 1).
Survey of the hospital sites showed that 46 % hospitals either did not have effluent treatment plants or the Table 1 Mercury levels in water effluents of hospitals Hospital code
Mercury concentration (μg/L) Inlet of ETP
Outlet of ETP/discharge line
1.
NT
NT
2.
NC
1.0
3.
NC
2.0
4.
NC
5.0
5.
1.0
1.0
6.
NC
2.0
7.
2.0
1.0
8.
NC
1.0
9.
4.0
4.0
10.
1.0
1.0
11.
NC
2.0
12.
2.0
1.0
13.
NT
NT
Permissible limit for discharge of mercury into inland surface water, public sewers and marine coastal areas is 0.01 mg/L (Schedule VI of The Environment (Protection) Rules, 1986) ETP effluent treatment plant, NT not traceable, NC not collected
Discussion The health-care sector is one of the important consumers of elemental mercury. Huge quantities of mercury are used in various medical devices. China, a leading manufacturer of thermometers and sphygmomanometers, produces an increasing number of medical devices for domestic consumption and export. In 2008, China used 227 tons of mercury for the manufacture of thermometers and sphygmomanometers solely. However, it has formulated a management strategy and action plan for a 5-year period (2011–2015) to reduce its contribution towards global mercury releases (www.cciced.net).In India, an estimated 26 tons of mercury is being used in healthcare instruments (Kumari et al. 2011). Since pollution due to mercury is a major environmental and human health problem, developed countries like the USA has addressed the problem and made a significant progress in implementing measures to shift to safer alternatives. The European Union has imposed a ban on mercury thermometers. There are also a growing number of hospitals in the developing countries, which are moving towards mercury-free health care (https://noharm-
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global.org). India like many other developed nations is also working towards the phasing out of mercurycontaining equipments from health-care facilities (Sengupta 2009; Agrawal 2009; Agrawal and Sinha 2012; gefmedwaste.org). However, the results of the present study show that the use of mercury-containing items mainly thermometers, sphygmomanometers, dental amalgam, CFLs, and OT bulbs still continues in the health-care sector of India. A questionnaire-based study conducted in selected hospitals representative of three states in India corroborates these findings, highlighting that mercurycontaining thermometers and sphygmomanometers would still be preferred because of their affordability, convenience in use, and accuracy (Halder et al. 2013). Asia is the largest source of mercury release, and China is the main contributor (www.cciced.net; Lin et al. 2012). In India, the total amount of mercury released through healthcare instruments is estimated to be 8 tons, major contributors being thermometers, sphygmomanometers, and dental amalgam (Agrawal et al. 2004). The estimated amount of mercury used in dental sector was 65 tons in 2011, with an estimated average release of 16 tons of noncontact amalgam into environment (Agrawal and Sinha 2012). The mercury spills in health-care facilities could be hazardous where health-care workers are unknowingly exposed to mercury due to breakage of thermometers and lack of mercury waste management protocols. A study conducted in Delhi reports an approximate breakage of 70 thermometers, in an average sized 300–500 bedded hospital every month. Mercury levels in ambient air of hospitals surveyed in Delhi have been found high, as compared to international standards of Environmental Protection Agency (0.3 μg/m3) for inhalation exposure (Pastore et al. 2007). The calibration rooms of sphygmomanometers also serve as hotspots of mercury release in the environment. Further, besides a hospital setting, medical devices like thermometers can be hazardous at home also. A children’s hospital in Argentina has documented at least 15 calls a month about mercury poisoning due to broken thermometers (http://noharm-global. org). The dental sector is an important contributor to the environment mercury load. It has been estimated that in India, an averaged-sized hospital with a dental wing could release conservatively 3 kg of mercury into the environment in a year (Agrawal et al. 2004). Regular breakage of thermometers in various hospitals releases
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vapors into the environment. Various reports from India have highlighted improper disposal and laxity in carrying out correct practices while using mercury in dental practices (Sudhakar and Chandrashekar 2008; Sood and Sood 2011). A study carried out in two north Indian cities in India reports 40.6 % dentists disposed off excess silver amalgam in common bins (Singh et al. 2014). The challenge of switching over to mercury-free alternatives involves issues like accuracy and economic feasibility. Numerous studies have now shown that accuracy of mercury-free instruments can be easily taken care of with proper maintenance and calibration of the instruments (Mion and Pierrin 1998; Canzanello et al. 2001). Alternatives are also economically viable in view of extensive breakage especially of thermometers. In fact, various countries have shown savings in expenditure after switching over to alternatives (http://noharm-global.org). Mercury-containing waste poses a serious threat to the environment. The results of the present study show that the methods mainly adopted by health-care facilities for mercury waste disposal are collection in plastic bags and labeling it as hazardous waste, auctioning as waste, and incineration. Incineration of hazardous hospital and municipal waste adds to the global mercury load. According to WHO, medical waste incineration from health-care facilities is one of the main sources of mercury release into the atmosphere (WHO 2005). Prior to phasing out of mercury in USA, the fourth largest source of mercury emission into the environment were the medical waste incinerators. Annually, around 15 metric tons of mercury from thermometers would go to solid waste landfills (USEPA, 1996). Further, the production of thermometers and sphygmomanometers pose a significant threat to the workers and the surrounding environment. The Kodaikanal incident in India documents a perfect picture of careless handling of mercury causing widespread contamination of the environment besides the occupational health-related problems of the workers (Karunasagar et al. 2006). There is anecdotal evidence suggesting that in most of the countries of Asia, Latin America, and Africa, the protocol for cleaning mercury spills is neither followed properly nor does segregation of waste take place. Frequently, broken and obsolete mercury-containing devices go to the incinerators, are flushed down the drains, or are sent to landfills or dumps making a significant contribution to environmental contamination. Only a fraction of these products goes for recycling after their use. In China, batteries and fluorescent lamps contribute significantly to municipal waste (Cheng and Hu 2012). It has been estimated
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that spent fluorescent lamps account for approximately 20 % of mercury in municipal solid waste (Hu and Cheng 2012). Even in India CFLs are discarded with household waste or sold to scrap dealers (www.cpcb.nic.in). Release of untreated wastewater from health-care facilities reportedly contaminates the water bodies. It has been reported that there is considerable mercury load due to dental practice in sewage systems in Canada (www.who.int). The hospitals in USA are reported to have contributed 4–5 % of waste water mercury load in the past (USEPA, 1996). However, the results of the present study showed that the mercury levels in various hospital effluents were below the permissible limit and in certain samples mercury was not even traceable, clearly pointing towards the mercury management policy in place and awareness about proper disposal in sample hospitals. In developed countries, use of mercury in various products and processes and disposal of mercurycontaining wastes is regulated by laws. In USA, the Resource Conservation and Recovery Act (RCRA), Solid Waste Combustion Rules (Section 129), and Reduction of Toxic Air Emissions from Combustion Sources that Burn Hazardous Waste are enforced for managing mercury effectively to protect the environment (www.epa.gov). The European Union and USA follow the Waste Electrical and Electronics Equipment (WEEE) directive and Universal Waste Rules for collection, treatment and safe disposal of mercury-contaminated used fluorescent lamps (www.cpcb.nic.in). Similarly, in India, there are various legislations for managing waste containing mercury. Such waste generated by health-care facilities falls under the category of “Hazardous waste” as defined under Schedule II of the Hazardous Waste (Management, Handling and Transboundary Movement) Rules, 2008 and amendments made thereof. The E-waste management (Management and Handling) Rules, 2011 are also in place for reducing the quantity of mercury in various equipments and managing wastes from a number of electrical and electronic products like CFLs, OT bulbs, and thermostats. (www.enlighten-initiative.org). The Central Pollution Control Board has also issued guidelines for environmentally sound management of mercury in fluorescent lamps (www.cpcb.nic.in). Further, a number of initiatives have also been taken by the government and nongovernment organizations, to reduce the use of mercury in health-care sector. The Department of Health of Delhi Government has issued directives for complete replacement of mercury-containing items with alternatives in a phased manner (Dastidar 2007).
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The issue of guidelines on mercury management in health-care facilities and the need to replace the mercurycontaining products with alternatives has been addressed by the Directorate General of Health Services of Ministry of Health & Family Welfare, Government of India in 2010 (www.mercuryfreehealthcare.org). Many hospitals in government and corporate sectors have already banned the use of mercury-containing items. The Government of India will join 100 countries by signing a new multilateral environmental agreement, the Minamata Convention, sketched to protect human health and the environment from anthropogenic releases of mercury and mercury compounds (www.hindustantimes.com).
Conclusion The resent study has the limitation of sample size and does not represent the whole country, but the results clearly show that mercury-containing items are still being used in India. Since the health-care sector plays an important role in mercury emission, stress on enforcement of compliance with the hospital mercury management policy and replacement of mercurycontaining items with accurate, affordable, and easily disposable alternatives is the need of the hour. Further, strict implementation of existing guidelines for sound management of mercury and its proper disposal is mandatory. The WHO has issued a policy paper on short-, medium-, and long-term measures to substitute mercury-containing medical devices with safer alternatives. In the interest of public health and the environment, implementation of broad strategies like source reduction, recycling, and waste minimization warrants attention. Emphasis should be on on-site storage, extended producer responsibility, national regulations, collection programmes, and global guidelines.
Acknowledgments The authors sincerely thank Dr. R.M Pandey, Head, Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, for his suggestions regarding the presentation of results. The funding for the project received from the Ministry of Environment and Forests, Government of India is highly acknowledged.
Conflict of interest The authors declare that there is no conflict of interest.
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Use of mercury-based medical equipments and mercury content in effluents of tertiary care hospitals in India Sharda Shah Peshin & Nabanita Halder & Chandrababu Jathikarta & Yogendra Kumar Gupta
Received: 7 August 2014 / Accepted: 3 November 2014 / Published online: 26 February 2015 # Springer International Publishing Switzerland 2015
Abstract Environmental pollution due to mercury has raised serious concern over the last few decades. Various anthropogenic sources including the health sector play a vital role in increasing the mercury load on the environment. Mercury poses an important health issue because of its indiscriminate disposal into the environment. There are numerous mercury-containing devices being used in the health-care setup. The objective of the study was to obtain information on the procurement and consumption of mercury-containing items in the current year, the methods adopted for disposal and the contamination of the hospital effluents with mercury. A questionnaire-based study was conducted in government and corporate hospitals from different states of India, for the quantitative assessment of use of mercury-based items in tertiary care hospitals in India (n = 113). The results showed that mercurycontaining items are still being used in India. The most common method adopted for disposal was collection in plastic bags and labeling them as hazardous waste. The Electronic supplementary material The online version of this article (doi:10.1007/s10661-015-4311-2) contains supplementary material, which is available to authorized users. S. S. Peshin : N. Halder : C. Jathikarta : Y. K. Gupta (*) Department of Pharmacology, All India Institute of Medical Sciences, New Delhi 110029, India e-mail: [email protected] S. S. Peshin e-mail: [email protected] C. Jathikarta Hazardous Waste Management Division, Central Pollution Control Board, Ministry of Environment & Forests (Government of India), East Arjun Nagar, Delhi 110032, India
hospital effluents contained mercury below the permissible limits. In view of the environmental pollution due to mercury and its adverse impact on health, efforts by the government are on for phasing out mercury-containing equipments from the health-care setup in India. Keywords Hospital effluents . Medical equipments . Mercury
Introduction Mercury is ubiquitously present as a pollutant in environment. It occurs naturally in the earth’s crust and is distributed throughout the environment through natural processes like volcanic eruptions, erosion of mineral deposits, and weathering of rocks. Various anthropogenic activities including combustion of coal and petroleum products, cement and chlor-alkali production, metallurgical activities, and medical waste incineration cause environmental pollution. Once released from any source, it eventually makes its way into the environment. The complex and long-range movements of mercury make it a global pollutant (Clarkson 2002). Mercury exists in three forms in the environment— elemental, inorganic, and organic. The three basic steps involved in the cycling of mercury in environment include (i) release of the mercury from its sources, (ii) transport and deposition, and (iii) biological conversion and uptake by living organisms. Elemental mercury is a liquid that vaporizes at ambient temperature and pressure. Mercury entering the ecosystem
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can cycle indefinitely. It is deposited in soil and water bodies, where microorganisms convert elemental mercury into highly toxic methyl mercury, which is taken up by aquatic plants and animals. Methyl mercury accumulates in organisms (bioaccumulation), and the concentrations increase up at each level of the food chain (biomagnification). Bioaccumulation and biomagnification effects result in mercury levels of toxicological concern with serious implications, especially for human beings (Clarkson 2002). In the last few years, there has been an increasing global concern about the mercury pollution and its impact over health. The adverse health effects mainly depend on the chemical form, route, dose, duration of exposure, and health and age of the person exposed. Elemental mercury is absorbed through inhalation affecting mainly the respiratory system. The primary tissues of distribution are the central nervous system and kidneys. Inorganic mercury mainly targets the kidneys and gastrointestinal system, whereas organic mercury especially methyl mercury affects the central nervous system. It is a neurotoxin affecting all age groups. The developing fetus especially in mothers consuming fish may be more vulnerable to methyl mercury than the adults. (www.epa.gov; Murata et al. 2011). The adverse effects of mercury on human health even when present in traces are well reported (Zahir et al. 2005). The health sector plays a significant role in the emission of mercury in environment due to huge demand in various instruments and thus contributes to environmental pollution in view of usage, breakage of mercury-containing products, and spills. The most widely used form in health-care devices is elemental mercury. The common mercurycontaining devices used in health-care sector include thermometers, sphygmomanometers, dental amalgams, gastrointestinal tubes, preservatives, fixatives, medical batteries, compact fluorescent lamps (CFLs), operation theatre (OT) bulbs, thermostats, etc. (Shaner 1997; Clarkson et al. 2003). Mercury-containing products upon breakage release mercury into the environment if discarded improperly (Pastore et al. 2007). Since mercury vaporizes at room temperature, the spills can also be a source of acute inhalation besides contaminating the environment. Leaked mercury from various products often ends up in water and soil due to improper disposal. Medical waste incineration further contributes to pollution. Hence, inadequate or improper disposal of mercury-containing waste pollutes the environment consequently endangering wildlife and human health. The problem of mercury pollution in health-care sector is being realized in India with focus on strategies on source reduction, waste minimization, safe storage
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and disposal, etc. (www.tnpcb.gov.in). India is also participating in an initiative aimed at phasing out mercurycontaining fever thermometers and sphygmomanometers by at least 70 % and switching over to alternatives by 2017 (www.mercuryfreehealthcare.org). Although the use of mercury in the health-care facilities in India has declined over the years, mercury-based equipments are still being used (Kumari et al. 2011). Due to the improper handling, disposal, and waste management of mercury-containing items, the hospitals are one of the major contributors of environmental pollution. With this background, the present questionnairebased study was designed to assess the current status of the extent of use of mercury-containing equipment and methods of disposal adopted by various hospitals in India. In addition, analysis of mercury levels in the final effluent of some tertiary care hospitals in the states of Delhi, Haryana, and Uttar Pradesh were also undertaken, to check contamination of hospital effluents with mercury due to improper disposal.
Material and methods
Quantitative estimation of the mercury items A questionnaire was designed to obtain information on procurement and consumption of mercury-containing items during the year 2009–2010 and the methods adopted for disposal by various tertiary care hospitals. It was sent to different hospitals in India (n=113), and the responses were tabulated.
Analysis of hospital effluent samples to estimate mercury levels Thirteen hospitals were selected for effluent analysis in the states of Delhi, Uttar Pradesh, and Haryana (govt. sector=47 %, corporate sector=53 %) in consultation with the Central Pollution Control Board, Government of India. The questionnaire-based survey on assessment of awareness about the environmental pollution due to mercury had already been carried out in these hospitals (Halder et al. 2013).
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Collection of effluent samples Effluent samples (1000 mL) were collected in ambercolored bottles rinsed with nitric acid solution in water (1:1). The samples were preserved by adding 2 ml of acidified potassium dichromate (20 % w/v K2Cr2O7 in HNO3, 1:1) and stored in a refrigerator at 4 °C.
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through the vapor generation system, carries elemental mercury from solution and then passes through the absorption cell. A standard curve of mercuric chloride was plotted. The absorbance of the test samples was recorded, and the concentration of mercury was calculated using the standard curve.
Results Digestion of effluent samples The digestion of the effluent samples (100 mL) was carried out in a biological oxygen demand (BOD) bottle by treatment with concentrated sulfuric acid (5 mL), nitric acid (2.5 mL), and potassium permanganate (5 %, 15 ml), and the mixture was allowed to stand for 15 min. Then potassium per sulfate (5 %, 8 ml) was added, bottle stoppered, and mixture heated on a water bath for 2 h at 95 °C. Post-cooling the mixture at room temperature, sodium chloride and hydroxylamine hydrochloride (120 g NaCl+120 g NH2OH·HCl in 1 L of distilled water, 5–6 mL) was added. Finally, 5 mL of stannous chloride (20 % SnCl2 in 10 % HCl) was added to each sample before analysis (APHA, 2005).
Mercury analysis Mercury levels in effluent samples were estimated using a Mercury Analyser (MA5840, Electronic Corporation of India, Hyderabad). Analysis is based on the cold vapor technique where the mercury vapor (atoms) absorbs resonance radiation at 253.7 nm. The carrier gas (air) bubbles Fig. 1 Use of mercurycontaining items in different hospitals in 2009–2010
Quantitative estimation of the mercury items The questionnaire-based proforma was sent to various hospitals (n=113, govt. sector=63.7 %, corporate sector=36.2 %). Only 45 hospitals (39 %) responded to the queries among which 41 (91 %) hospitals indicated use of mercury-containing items. While analyzing the data obtained from 41 hospitals for the overall use of mercury containing items, the results showed 32 % hospitals had reduced the use of these items, while there was an increase in use of these items in 22 % hospitals. However, 14 % of the hospitals indicated no change in use of mercury-containing items as compared to the previous year. Moreover, 32 % of hospitals did not respond to this question (Fig. 1). The results have shown that sphygmomanometers and thermometers (95 and 85 %) are still being used by hospitals. Mercury-containing compact fluorescent lamps and operation theatre bulbs were used by 82 and 65 % hospitals. However, only 21 % hospitals used esophageal dilators. Dental amalgam was found to be used by 31 % hospitals (Fig. 2).
145 Page 4 of 8 Fig. 2 Use of different mercurycontaining items in hospitals (%)
Environ Monit Assess (2015) 187: 145 TH: Thermometer SP : Sphygmomanometer ED :Esophageal dilator CFL : Compact fluorescent lamps OTB : Operaon theatre bulbs DA: Dental amalgam
100 90 80 70 60 50 40 30 20 10
0 TH
SP
ED
CFL
OTB
DA
Mercury-containing items
Comparison of the trend of procurement of individual mercury-containing items by various hospitals has shown that an attempt was made by27 and 34 % hospitals towards less procurement of thermometers and sphygmomanometers, respectively. However, at the same time, increased procurement of thermometers (27 %) and sphygmomanometers (22 %) was also reported by hospitals. There was observed an increase in the procurement of compact fluorescent lamps by 35 % and operation theatre bulbs by
Fig. 3 Trend in procurement of individual mercury-containing items by hospitals as compared to the previous year
22 % hospitals. In a fraction of hospitals, the procurement status remained the same as the previous year (Fig. 3). Various methods were used for the disposal of mercurycontaining waste, and it was observed that collecting the mercury waste in separate plastic bags, sealing, and disposal was a common practice followed by majority of hospitals (35 %). Auctioning as a waste was done by 22 % of the hospitals. Only 15 % hospitals incinerated the mercury-containing waste, and 10 % got it disposed off
Environ Monit Assess (2015) 187: 145
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Fig. 4 Methods of mercury waste disposal by various hospitals (%)
by the Municipal Corporation. However, 17 % of the hospitals used other methods for disposal (Fig. 4).
Mercury estimation in hospital effluents
existing facility was not in a working condition. Analysis of the results for effluents of the hospitals surveyed (n=13, govt. sector=47 %, corporate sector=53 %), showed that mercury levels in the hospitals were below the permissible limit for public sewers. Mercury was not traceable in the effluents of only two corporate hospitals (Table 1).
Survey of the hospital sites showed that 46 % hospitals either did not have effluent treatment plants or the Table 1 Mercury levels in water effluents of hospitals Hospital code
Mercury concentration (μg/L) Inlet of ETP
Outlet of ETP/discharge line
1.
NT
NT
2.
NC
1.0
3.
NC
2.0
4.
NC
5.0
5.
1.0
1.0
6.
NC
2.0
7.
2.0
1.0
8.
NC
1.0
9.
4.0
4.0
10.
1.0
1.0
11.
NC
2.0
12.
2.0
1.0
13.
NT
NT
Permissible limit for discharge of mercury into inland surface water, public sewers and marine coastal areas is 0.01 mg/L (Schedule VI of The Environment (Protection) Rules, 1986) ETP effluent treatment plant, NT not traceable, NC not collected
Discussion The health-care sector is one of the important consumers of elemental mercury. Huge quantities of mercury are used in various medical devices. China, a leading manufacturer of thermometers and sphygmomanometers, produces an increasing number of medical devices for domestic consumption and export. In 2008, China used 227 tons of mercury for the manufacture of thermometers and sphygmomanometers solely. However, it has formulated a management strategy and action plan for a 5-year period (2011–2015) to reduce its contribution towards global mercury releases (www.cciced.net).In India, an estimated 26 tons of mercury is being used in healthcare instruments (Kumari et al. 2011). Since pollution due to mercury is a major environmental and human health problem, developed countries like the USA has addressed the problem and made a significant progress in implementing measures to shift to safer alternatives. The European Union has imposed a ban on mercury thermometers. There are also a growing number of hospitals in the developing countries, which are moving towards mercury-free health care (https://noharm-
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global.org). India like many other developed nations is also working towards the phasing out of mercurycontaining equipments from health-care facilities (Sengupta 2009; Agrawal 2009; Agrawal and Sinha 2012; gefmedwaste.org). However, the results of the present study show that the use of mercury-containing items mainly thermometers, sphygmomanometers, dental amalgam, CFLs, and OT bulbs still continues in the health-care sector of India. A questionnaire-based study conducted in selected hospitals representative of three states in India corroborates these findings, highlighting that mercurycontaining thermometers and sphygmomanometers would still be preferred because of their affordability, convenience in use, and accuracy (Halder et al. 2013). Asia is the largest source of mercury release, and China is the main contributor (www.cciced.net; Lin et al. 2012). In India, the total amount of mercury released through healthcare instruments is estimated to be 8 tons, major contributors being thermometers, sphygmomanometers, and dental amalgam (Agrawal et al. 2004). The estimated amount of mercury used in dental sector was 65 tons in 2011, with an estimated average release of 16 tons of noncontact amalgam into environment (Agrawal and Sinha 2012). The mercury spills in health-care facilities could be hazardous where health-care workers are unknowingly exposed to mercury due to breakage of thermometers and lack of mercury waste management protocols. A study conducted in Delhi reports an approximate breakage of 70 thermometers, in an average sized 300–500 bedded hospital every month. Mercury levels in ambient air of hospitals surveyed in Delhi have been found high, as compared to international standards of Environmental Protection Agency (0.3 μg/m3) for inhalation exposure (Pastore et al. 2007). The calibration rooms of sphygmomanometers also serve as hotspots of mercury release in the environment. Further, besides a hospital setting, medical devices like thermometers can be hazardous at home also. A children’s hospital in Argentina has documented at least 15 calls a month about mercury poisoning due to broken thermometers (http://noharm-global. org). The dental sector is an important contributor to the environment mercury load. It has been estimated that in India, an averaged-sized hospital with a dental wing could release conservatively 3 kg of mercury into the environment in a year (Agrawal et al. 2004). Regular breakage of thermometers in various hospitals releases
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vapors into the environment. Various reports from India have highlighted improper disposal and laxity in carrying out correct practices while using mercury in dental practices (Sudhakar and Chandrashekar 2008; Sood and Sood 2011). A study carried out in two north Indian cities in India reports 40.6 % dentists disposed off excess silver amalgam in common bins (Singh et al. 2014). The challenge of switching over to mercury-free alternatives involves issues like accuracy and economic feasibility. Numerous studies have now shown that accuracy of mercury-free instruments can be easily taken care of with proper maintenance and calibration of the instruments (Mion and Pierrin 1998; Canzanello et al. 2001). Alternatives are also economically viable in view of extensive breakage especially of thermometers. In fact, various countries have shown savings in expenditure after switching over to alternatives (http://noharm-global.org). Mercury-containing waste poses a serious threat to the environment. The results of the present study show that the methods mainly adopted by health-care facilities for mercury waste disposal are collection in plastic bags and labeling it as hazardous waste, auctioning as waste, and incineration. Incineration of hazardous hospital and municipal waste adds to the global mercury load. According to WHO, medical waste incineration from health-care facilities is one of the main sources of mercury release into the atmosphere (WHO 2005). Prior to phasing out of mercury in USA, the fourth largest source of mercury emission into the environment were the medical waste incinerators. Annually, around 15 metric tons of mercury from thermometers would go to solid waste landfills (USEPA, 1996). Further, the production of thermometers and sphygmomanometers pose a significant threat to the workers and the surrounding environment. The Kodaikanal incident in India documents a perfect picture of careless handling of mercury causing widespread contamination of the environment besides the occupational health-related problems of the workers (Karunasagar et al. 2006). There is anecdotal evidence suggesting that in most of the countries of Asia, Latin America, and Africa, the protocol for cleaning mercury spills is neither followed properly nor does segregation of waste take place. Frequently, broken and obsolete mercury-containing devices go to the incinerators, are flushed down the drains, or are sent to landfills or dumps making a significant contribution to environmental contamination. Only a fraction of these products goes for recycling after their use. In China, batteries and fluorescent lamps contribute significantly to municipal waste (Cheng and Hu 2012). It has been estimated
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that spent fluorescent lamps account for approximately 20 % of mercury in municipal solid waste (Hu and Cheng 2012). Even in India CFLs are discarded with household waste or sold to scrap dealers (www.cpcb.nic.in). Release of untreated wastewater from health-care facilities reportedly contaminates the water bodies. It has been reported that there is considerable mercury load due to dental practice in sewage systems in Canada (www.who.int). The hospitals in USA are reported to have contributed 4–5 % of waste water mercury load in the past (USEPA, 1996). However, the results of the present study showed that the mercury levels in various hospital effluents were below the permissible limit and in certain samples mercury was not even traceable, clearly pointing towards the mercury management policy in place and awareness about proper disposal in sample hospitals. In developed countries, use of mercury in various products and processes and disposal of mercurycontaining wastes is regulated by laws. In USA, the Resource Conservation and Recovery Act (RCRA), Solid Waste Combustion Rules (Section 129), and Reduction of Toxic Air Emissions from Combustion Sources that Burn Hazardous Waste are enforced for managing mercury effectively to protect the environment (www.epa.gov). The European Union and USA follow the Waste Electrical and Electronics Equipment (WEEE) directive and Universal Waste Rules for collection, treatment and safe disposal of mercury-contaminated used fluorescent lamps (www.cpcb.nic.in). Similarly, in India, there are various legislations for managing waste containing mercury. Such waste generated by health-care facilities falls under the category of “Hazardous waste” as defined under Schedule II of the Hazardous Waste (Management, Handling and Transboundary Movement) Rules, 2008 and amendments made thereof. The E-waste management (Management and Handling) Rules, 2011 are also in place for reducing the quantity of mercury in various equipments and managing wastes from a number of electrical and electronic products like CFLs, OT bulbs, and thermostats. (www.enlighten-initiative.org). The Central Pollution Control Board has also issued guidelines for environmentally sound management of mercury in fluorescent lamps (www.cpcb.nic.in). Further, a number of initiatives have also been taken by the government and nongovernment organizations, to reduce the use of mercury in health-care sector. The Department of Health of Delhi Government has issued directives for complete replacement of mercury-containing items with alternatives in a phased manner (Dastidar 2007).
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The issue of guidelines on mercury management in health-care facilities and the need to replace the mercurycontaining products with alternatives has been addressed by the Directorate General of Health Services of Ministry of Health & Family Welfare, Government of India in 2010 (www.mercuryfreehealthcare.org). Many hospitals in government and corporate sectors have already banned the use of mercury-containing items. The Government of India will join 100 countries by signing a new multilateral environmental agreement, the Minamata Convention, sketched to protect human health and the environment from anthropogenic releases of mercury and mercury compounds (www.hindustantimes.com).
Conclusion The resent study has the limitation of sample size and does not represent the whole country, but the results clearly show that mercury-containing items are still being used in India. Since the health-care sector plays an important role in mercury emission, stress on enforcement of compliance with the hospital mercury management policy and replacement of mercurycontaining items with accurate, affordable, and easily disposable alternatives is the need of the hour. Further, strict implementation of existing guidelines for sound management of mercury and its proper disposal is mandatory. The WHO has issued a policy paper on short-, medium-, and long-term measures to substitute mercury-containing medical devices with safer alternatives. In the interest of public health and the environment, implementation of broad strategies like source reduction, recycling, and waste minimization warrants attention. Emphasis should be on on-site storage, extended producer responsibility, national regulations, collection programmes, and global guidelines.
Acknowledgments The authors sincerely thank Dr. R.M Pandey, Head, Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, for his suggestions regarding the presentation of results. The funding for the project received from the Ministry of Environment and Forests, Government of India is highly acknowledged.
Conflict of interest The authors declare that there is no conflict of interest.
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