Users’ ManualTraining package for mercury
monitoring to enhance national
capacity to generate internationallycomparable scientific data

Ver. 1.0

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Users’ ManualTraining package for mercury
monitoring to enhance national
capacity to generate internationallycomparable scientific data

Ver. 1.0

Acknowledgements: UNEP ROAP wishes to thank all individuals and organizations that have contributed theirexpertise, time, and energy to this work, in particular IDEA Consultants, Inc., which provided videos and photos
on the field and laboratory works for mercury monitoring. Particular thanks go to Hiromitsu Nagasaka, Keisuke
Uchida, and Tatsuya Hattori (IDEA Consultants) who provided the wealth of knowledge and experiences on
mercury monitoring and generously provided its laboratory for video taking. The majority of the material inthis training package is a reproduction of the online training programme held in December 2021. The
administrative and logistical support by Guilberto Borongan and Solomon Huno (Asian Institute of Technology
AIT) in organizing the programme became indispensable guidance in this ‘Users’ Manual’. All participants tothe online training programme also contributed to this training package through their active participation in
the Q&A sessions. This training package was reviewed by Alfrida Esther Suoth (Environmental Monitoring
Centre EMC), Dewi Ratnaningsih (EMC), Eisaku Toda (Minamata Secretariat), Ely Rachmi Tapriziah (EMC),
Ernawita Nazir (EMC), Hiromitsu Nagasaka (IDEA), Kenneth Davis (UNEP), Koichi Haraguchi (National Institutefor Mimanata Disease), Minoru Koga (Minamata Academia), Muhammad Iqbal Suryatama (EMC), Rento Puji
Lestari (EMC), Ricky Nelson (EMC), Rina Aprishanty (EMC), Sufenal Healthy (EMC), Tatsuya Hattori (IDEA),
Vincent Lal (University of South Pacific UPC), and Yunesfi Sofyan (EMC). This publication is the culminationof the hard work and dedication of the editorial team led by Yayoi Hayashi (Overseas Environmental
Cooperation Center OECC). Her team, including Reiko Hoshino, Fumi Matsumura, and Kanae Komaki (OECC),
worked tirelessly to create this high-quality product within very tight deadline. Finally, we would like to express
our deep appreciation to the generous support made by Ministry of the Environment of Japan, particularly
Hitoshi Yoshizaki and Itsuki Kuroda under its MOYAI Initiative. With their support, the mercury management
capacity in developing countries will be further strengthened.
Funding: The work to develop the training package including this Users’ manual and the annexes has been
funded by Government of Japan.

CONTENTS
Executive summary .................................................................................................................................. v
1

Background ........................................................................................................................... 1
1.1

Global mercury issues .......................................................................................................... 1

1.2

Context of this Training Package ......................................................................................... 1

1.3

Development of this training package................................................................................. 22

Introduction ........................................................................................................................... 5
2.1

Purpose.................................................................................................................................. 5

2.2

Limitation............................................................................................................................... 6

3

Trainers’ guidance................................................................................................................. 7
3.1

Course design ....................................................................................................................... 7

3.2

Sample concept note .......................................................................................................... 12

3.3

Sample training course....................................................................................................... 14

3.4

Laboratory capacity self-assessment ............................................................................... 18

3.5

Pre- and post-training self-test and evaluations ............................................................... 23

3.6

Frequently Asked Questions .............................................................................................. 28

4

Supplementary information and literature ........................................................................ 37
4.1

Outlines of Minamata Convention on Mercury ................................................................. 37

4.2

Standards and guideline values ......................................................................................... 40

4.3

Process flows...................................................................................................................... 47

4.4

List of certified reference materials .................................................................................. 51

4.5

Physical and chemical properties, usage, and environmental behaviours of mercury . 52

4.6

Reference literatures and websites ................................................................................... 64

4.7

Glossary, acronyms, and abbreviations ............................................................................. 69

5

Editable PowerPoint files ................................................................................................... 71
5.1

List of slide decks ............................................................................................................... 71

5.2

Lecture 1 Physical and chemical properties, usage, and environmental behaviour ...... 73

5.3

Lecture 2 Atmospheric survey and analysis (manual active sampling method) ........... 79

5.4

Lecture 3: Solid sample (soil, sediment, and biota) survey and analysis ....................... 93

5.5

Lecture 4: Water sample survey and analysis ................................................................103

5.6

Lecture 5: Human biological sample analysis ................................................................110

5.7

Lecture 6: Methylmercury analysis ..................................................................................115

5.8

Lecture 7 Mercury monitoring and the Minamata Convention ......................................118

iii

6

5.9

Lecture 8: Quality management .......................................................................................123

5.10

Lecture 9: Laboratory safety and environmental management ....................................134
List of annexes ..................................................................................................................140

TABLES
Table 1 Areas covered by the training package ...................................................................................... 8
Table 2 Advantages and limitations of online and face-to-face programmes ..................................... 9
Table 3 Time zone table when organizing multi-country training ....................................................... 10
Table 4 Article-by-article outlines of the Minamata Convention ......................................................... 38
Table 5 Air (mercury standards and guideline values) ......................................................................... 40
Table 6 Water (mercury standards and guideline values) ................................................................... 41
Table 7 Soil (mercury standards and guideline values) ....................................................................... 41
Table 8 Sediment (mercury standards and guideline values) ............................................................. 42
Table 9 Fish and other food items (mercury standards and guideline values) .................................. 42
Table 10 Waste (mercury standards and guideline values)................................................................. 43
Table 11 Air emissions (mercury standards and guideline values) .................................................... 43
Table 12 Hair and blood (reference value corresponding to mercury tolerable intake) .................... 46
Table 13 Certified reference materials of mercury .............................................................................. 51
Table 14 Physical properties of elemental mercury ............................................................................. 52
Table 15 Exposure pathway, symptom and treatment ......................................................................... 53
Table 16 Applications of elemental mercury ........................................................................................ 56
Table 17 Applications of amalgam........................................................................................................ 59
Table 18 Applications of mercury compounds..................................................................................... 61

FIGURES
Figure 1 Flowchart of total mercury analysis by acid digestion – aeration CVAAS .......................... 47
Figure 2 Flowchart of total mercury analysis in water by dithizone extraction aeration CVAAS ...... 48
Figure 3 Flowchart of methylmercury analysis in biological sample by dithizone extraction GC/ECD.......................................................................................................................................................... 49
Figure 4 Flowchart of methylmercury analysis in hair sample by HCl extraction GC/ECD ............... 50
Figure 5 Molecular similarity of methylmercury-cysteine complex and methionine ......................... 52
Figure 6 Historical mercury supply and use ......................................................................................... 54
Figure 7 Global mercury uses by sector and by region ........................................................................ 55
Figure 8 Global atmospheric mercury emissions by sector and by region ........................................ 63iv

EXECUTIVE SUMMARY
Mercury is a chemical element that has existed on Earth since its creation. Mercury is released fromnatural sources by processes, such as volcanic activity and permafrost melting. In recent years,
more mercury has been released through human activities, such as the combustion of fuels, mining
activities, and the consumption of mercury-added products. Once emitted to the atmosphere,
mercury remains for a long time, and will be transported long distances. Atmospheric mercury is
eventually oxidized, and then deposited in the ocean or on land.
Growing concerns for mercury risks have resulted in the adoption and entry into force of the
Minamata Convention on Mercury (the Convention). The Parties to the Convention are obliged to
inform the Conference of the Parties about the national situation and implementation. There is a
growing need for capacity building concerning appropriate mercury monitoring skills in developing
countries to ensure the proper implementation of the required efforts under the Convention bymonitoring the levels of mercury and mercury compounds.
The ‘Training package for mercury monitoring to enhance national capacity to generateinternationally comparable scientific data’ addresses specific skills for laboratory managers andtechnicians to produce reliable data. It enhances national capacity to generate scientific data byusing multimedia and focusing on different applications that meets internationally acceptable level.
The material provides not only manual skills to use devices and instruments, but also informationon the principles of quality assurance and quality control to address comparability issues. Quality isthe value of produced data. Practical examples to reduce data bias and uncertainty are also provided.
The training package is composed of multimedia files, i.e., videos, which provide substantive
information when organizing a training programme. The video material is prepared using Microsoft
PowerPoint with pre-recorded narration embedded in each slide and then grouped by deck in each
topic/subject. This Users’ Manual provides a sample course with full scope that uses the materials
in one consistent programme, but the training package does not need to be used in full. The
organizer can prepare the ‘custom-made’ slide decks for its own training programme. The following
video lectures are annexed to the Users’ Manual:
▪
▪
▪
▪
▪
▪
▪
▪

Physical and chemical properties, usage, and environmental behaviours
Atmospheric survey and analysis (manual active sampling method)
Solid sample (soil, sediment, and biota) survey and analysis
Water sample survey and analysis
Human biological sample analysis
Methylmercury analysis
Mercury monitoring and the Minamata Convention
Quality managementv▪

Laboratory safety and environmental management

The main body of the training package covers the specific skills for mercury analysis and laboratory
management. It also provides general knowledge on mercury science and its regulatory frameworkas the foundation and for better understanding of the issue to the audiences who acquires specificskills through this material. However, it is not designed to fit all occasions universally but instead toprovides specific information for the audiences who need the practical knowledge and skills on
mercury monitoring. Therefore, when designing a training programme, the organizer should firstly
develop a conceptual idea for a capacity strengthening activity and consider if any part of thismaterial can benefit the purpose of the activity.
This material provides practical and hands-on information to enable self-study to address needs inan online setting even under travel restrictions such as during the COVID-19 pandemic. Scientists
and practitioners of mercury management at national level is the primary target audiences for thismaterial. It can also be used by lecturers or trainers as teaching material as it has been developedwith customizable multimedia files to fit to their teaching syllabus.
The training programme can be organized in face-to-face, online, or hybrid settings. In each case,the facilitator(s) will run the programme and guide the audiences / participants to certain direction.
Online programmes are an emerging training style which has rapidly developed and expended in thepast few years. New online platforms and applications have been introduced and become moreversatile. However, mercury monitoring is an activity that involves field sampling and laboratory
analysis, which cannot be completed virtually. This training package includes many videos from thefield and laboratory so that the participant may also exercise the procedures in a face-to-face setting.

vi

1 BACKGROUND
1.1 Global mercury issues
Mercury is a chemical element that has existed on Earth since its creation. Mercury is released fromnatural sources by processes, such as volcanic activity and permafrost melting. In recent years,
more mercury has been released through human activities, such as the combustion of fuels, mining
activities, and the consumption of mercury-added products.
Once emitted to atmosphere, mercury remains for long time, and will be transported long distances.
Atmospheric mercury is eventually oxidized, and deposited in the ocean or on land. As mercury
levels in the air, ocean and soil are in equilibrium, more legacy mercury is re-emitted to theatmosphere. Some inorganic mercury in water bodies can be methylated by microbial activities, andbioaccumulated in biota at higher trophic levels. Eventually, fishing brings mercury back to humansociety through consumption. Excessive exposure to mercury, especially methylmercury, will poserisk to vulnerable population, particularly pregnant women as methylmercury actively passes
through placenta barrier by amino acid transporter to fetus.
Due to its environmental behaviours and anthropogenic emissions and releases, growing concerns
about mercury risks have resulted in the adoption and entry into force of the Minamata Convention
on Mercury (the Convention). It is one of the newest multilateral environmental agreements aiming
at protecting human health and the environment from anthropogenic emissions and releases of
mercury and mercury compounds.
In October 2013, the Diplomatic Conference on the Convention was convened in Kumamoto City inJapan, with a ceremonial opening in Minamata City, to formally adopt the Convention and open it
for signature. It entered into force in August 2017 and the Parties to the Convention must abide by
the provisions stipulated in the Convention text.

1.2 Context of this Training Package
The Minamata Convention obliges the Parties to take various measures to protect human healthand the environment from anthropogenic emissions and releases of mercury. Its preamble also
clarifies that the Parties can take additional measures beyond the requirements of the Convention’s
provisions. To effectively protect human health and the environment from mercury, it is importantto understand the levels of mercury in the environment and other matrices, which lead to1

environmental and human exposure to mercury. Article 19 (research, development, and monitoring)of the Convention requires the Parties to cooperate to develop and improve geographically
representative monitoring of the levels of mercury in the environmental media and humanpopulations. Article 18 (public information, awareness and education) also stipulates that eachParty shall provide to the public of available information on research, development and monitoring
activities under Article 19. Article 16 (health aspects) refers to the monitoring of health risk.
Technical guidance developed under specific articles also provides guidance on monitoring, suchas artisanal and small-scale gold mining site monitoring under Article 7, emission monitoring under
Article 8, and contaminated site monitoring under Article 12. For the effective implementation of theConvention, it is crucial to identify the priority areas from available data concerning the status of
trade, use, emission/release and disposal of mercury at the national level and to translate them into
domestic policy. Moreover, Article 22 (effectiveness evaluation) requires the Conference of theParties (COP) to evaluate the effectiveness of the Convention, based on information including
monitoring data on the presence and movement of mercury in the environment and humanpopulations. The Parties may also wish to investigate the effectiveness of their domestic measures
based on local, national or regional monitoring activities.
There is a growing need for capacity building concerning appropriate mercury monitoring skills indeveloping countries to ensure the effective implementation of the provisions of the Convention bymonitoring the levels of mercury and mercury compounds. Such capacity building can contribute to
the prioritization of policies, planning and implementation of mercury control measures and theevaluation of policy measures.
Mercury monitoring requires specific skills for laboratory managers and technicians to produce
reliable data. The training package for monitoring laboratories that monitor mercury levels will
enhance national capacity to generate scientific data by using multimedia and focusing on different
applications that are internationally comparable. The material provides not only manual skills to use
devices and instruments, but also information on the principles of quality assurance (QA) and quality
control (QC) to address comparability issues. Quality is the value of produced data. Practicalexamples to reduce data bias and uncertainty are also provided.

1.3 Development of this training package
UNEP Regional Office in Asia and the Pacific (ROAP) is implementing a Japan-funded project called“Project for promoting the Minamata Convention on Mercury by making the most of Japan's

2knowledge and experiences1” to support its member states, regardless of the ratification status forthe implementation of the Convention.
Most of the presentation materials are developed along with the online training programmes of the
project between December 2020 and February 2022. They are primarily developed to support the
project partner countries in Asia and the Pacific, but the content can be applied universally beyond
the geographical regions and sectors. Building on these materials, the training package can bereconfigured to be relevant to more generic needs so that it can be distributed and made available
globally.
The training package is composed of multimedia files, i.e., videos, which provide substantive
information when organizing a training programme. The video material is prepared using Microsoft
PowerPoint with pre-recorded narration embedded in each slide, then grouped by deck in each
topic/subject. All contents were compiled into a form of ‘Users’ manual’, which includes not only thepresentation videos but also sample training course, pre- and post-training self-test and evaluations,and the background information. This training package enables users to customize their own
training programmes by selecting, adding, or modifying the contents. It can easily integrate theadditional cross-cutting issues such as gender and human rights available in the reference literaturesection.

1

Project makes special focus in the area of information exchange (Article 17), awareness and education(Article 18), and research, development and monitoring (Article 19) to contribute the early implementation of
the Convention. A comprehensive programme is designed to strengthening enabling capacity, building on the
resources in and around Minamata, and employing technologies held by institutions in Japan.

34

2 INTRODUCTION
2.1 Purpose
This document intends to support the Parties and stakeholders to enhance mercury monitoring andanalytical capacity to contribute to the prioritization of policies, planning and implementation of
mercury control measures and the evaluation of the implemented policies.
The Minamata Convention includes a number of specific provisions related to mercury monitoring.
Firstly, Article 19 provides for cooperation among the Parties on research, development, andmonitoring. The geographically representative monitoring of levels of mercury and mercury
compounds in vulnerable populations and in environmental media is encouraged particularly in acollaborative manner for the collection and sharing of such samples.
Secondly, Article 16 provides for the monitoring of health risks related to the exposure to mercury
and mercury compounds by strengthening institutional and individual capacities in the health sector.
Thirdly, Articles 18 requires the Parties to promote and facilitate the provision of the monitoring
results to the public.
Fourthly, Article 22 requires that the monitoring information is utilized to evaluate the effectivenessof the Convention. In particular, comparative and representative monitoring data, both spatially andtemporally, will be a very useful information for the COP to examine the global situation and impactof the intervention. The COP prepared scientific and technical guidance to obtain comparable
monitoring data to evaluate the effectiveness of the Convention.
This document is expected to support the Parties in generating comparable monitoring data as
stipulated in the articles above. The document will also support governments, academia, and otherorganizations to develop and improve QC and QA mechanisms throughout its operation procedures.
This material provides practical and hands-on information with multimedia files (video) to enable
their self-study to address their needs in online setting even under the travel restriction such as
COVID-19 pandemic. Scientists and practitioners of mercury management at the national level are
the primary target audiences for this material. It can also be used by lecturers or trainers as theirteaching material as it is developed with customizable multimedia files to fit to their teachingsyllabus.

52.2 Limitation
Mercury issues are diverse and the needs on each occasion of different countries are significantly
different. This training package provides knowledge and skills at intermediate level with relatively
limited timeframe. For further advancement, additional capacity strengthening programmes should
be organized in order to address the specific knowledge and skills which are beyond the scope of
this training package.
In addition, this training will not completely replace the face-to-face or hands-on training, which canprovide more comprehensive and intensive capacity strengthening opportunities. This material will
sufficiently cover the environmental and biological media, where human health and environmental
conservation are of concern. There is also a need for mercury monitoring in other media, for example,
the mercury content in products should be monitored for law compliance checks. However, themethodologies and necessary instruments are very different, so these items are not covered.

6

3 TRAINERS’ GUIDANCE
3.1 Course design
The needs of capacity strengthening are diverse. Numerous activities are developed andimplemented by many organizations and individuals. Before developing a training programme, it isessential to recognize its purpose and logical relation towards the problem that the training
programme is going to address. The objective, or desired outcome, is the most important motives
for developing a training programme. The needs of the audiences are another important aspect thatshould be appropriately assessed or set as the first step of the programme development. If theaudiences are the internal staff of an organization, the capacity strengthening needs would bealigned with its short- or long-term strategy and should be systematically addressed. It is
recommendable to develop a concept note that outlines the background, objective, and key
arrangement. The concept note will be shared among stakeholders and discussed for elaborating
the training course in detail.
The ‘training package for mercury monitoring to enhance national capacity to generateinternationally comparable scientific data’ can serve as the substantive input to the activities either
partially or entirely.
This material is configured with lectures and supplemental materials on general knowledge andspecific skills (Table 1). The main body of the training package covers the specific skills on mercury
analysis and laboratory management. It also provides general knowledge on mercury science andits regulatory framework as the foundation and for better understanding of the issues by theaudiences who acquires specific skills through this material. However, it is not designed to fit all
occasions universally but provides specific information for the audiences who need the practicalknowledge and skills on mercury monitoring. Therefore, when designing a training programme, theorganizer should firstly develop a conceptual idea for a capacity strengthening activity and consider
if any part of this material can benefit the purpose of the activity. It is particularly the case for the
cross-cutting topics such as gender and human rights, which could be underlined throughout the
programme concept. Key reference literatures are developed by Strategic Approach to International
Chemicals Management (2017), UNEP (2016), and UNEP and Minamata Convention (2021) andavailable online. They will provide the fundamental concept of the human-environment interactions
in line with the principle of ‘leaving no one behind.’7

Table 1 Areas covered by the training package
General knowledge
Science and technology:- Physical and chemical properties,
usage, and environmental
behaviours

Regulatory framework:- The Minamata Convention- Standards and guideline values

Specific skill
Analytical skills:- Atmospheric survey and analysis- Solid sample (soil, sediment, and biota) survey andanalysis- Water sample survey and analysis- Human biological sample analysis- Methylmercury analysis
Management skills:- Quality management- Laboratory safety / environmental management

This Users’ manual provides a sample course with full scope that uses the materials in one
consistent programme, but the training package does not need to be used in full. The organizer can
prepare the ‘custom-made’ slide decks from the editable PowerPoint slides of this manual with prerecorded narration, to fit for its own training programme.
It is recommendable to appoint facilitator(s) to run the sessions of the training programme. The
facilitator is not necessarily an expert in mercury monitoring as the technical details are provided by
the videos of this training package. Nevertheless, it is recommended that (s)he has sufficientunderstanding about the context and purpose of the organizing programme.

Face-to-face or online
The training programme can be organized in face-to-face, online, or hybrid settings. In each case,the facilitator(s) will run the programme and guide the audiences/participants to a certain direction.
Online programmes are an emerging training style which has rapidly developed and expended in thepast few years. New online platforms and applications have been introduced and become moreversatile. However, this approach has some inherent limitation particularly for the topics of mercury
monitoring programme. Mercury monitoring is an activity that involves field sampling and laboratory
analysis, which are hands-on skills that cannot be completed virtually. Therefore, a hybridarrangement that combines the video lectures and field/laboratory visits could enhance theunderstanding and hands-on skills of the participants. This training package includes many videos
in the field and the laboratory so that the participant may also exercise the procedures in a face-to-8face setting as well. The advantages and limitations of online and face-to-face programme settings
are described in Table 2.

Table 2 Advantages and limitations of online and face-to-face programmes
Online programme
Logistical arrangement:- Travel arrangements are not required, travel
costs are saved.
- More people can participate in the programme.
Time management:- Programme date is flexible. Easy to formulate aseries of programmes with certain intervals.
(e.g., split into two part and insert
intersessional exercise)- Time zone difference should be considered
carefully.

Face-to-face programme
Logistical arrangement:- In the case of local training, most participants
live nearby and easily come together.
- Field tour, courtesy visit, or other field activities
can improve/broaden the understanding of theissue.
Time management:- Full day programmes are possible to intensify
the programme with a shorter duration.
- More ‘active’ participation is expected rather
than silent listeners.

Facility:- Internet connectivity of each participant might
be different. Connection cost might be high insome countries.
- Applications for online platform such as Webex
or Zoom should be installed in computers orother communication devices. The available
functions vary in different set up.

Facility:- Meeting venue must be secured for the training
programme.
- Demonstration of instruments may require
dedicated site, room, or facility.

Communications:- Difficult to separate from daily work as theparticipants are physically sitting at theirworking places.

Communications:- Interactive communication is facilitated.
Teambuilding exercise are effective.

Recording and reporting:- Due to the virtual nature, confirmation of theattendance of the participants is challenging.

Recording and reporting:- Photos and products of the training
programmes are more appealing in the activity
report.

Multi-country or one country
If the participants of training programme come from multiple countries or regions, time zone
difference should be carefully considered. The time zone table indicates the time differences ofmajor cities and possible time setting to cover large geographic areas. Programmes covering wide

9

geographical area are efficient to train many participants at once, but time allocation is smaller as
participants staying up to midnight or getting up before dawn may not be well prepared. The timezone table guides the online programme organizers in finding appropriate time arrangement
depending on the geographical coverage of the planned programmes. Unless essential, inviting
participant from across the entire globe should be avoided. Two out of three time zones, i.e., Africa,
Asia and America could be targeted at most. Table 3 indicates possible time slot arrangements insuch extreme cases. If the geographical coverage or time difference is smaller, more available time
allocation can be found, which is more comfortable to the participants.

Table 3 Time zone table when organizing multi-country training
Location
Suva (UTC+12)
Tokyo, Koror (UTC+9)
Manila, Kuala Lumpur,
Ulaanbaatar (UTC+8)
Bangkok, Jakarta, Hanoi(UTC+7)
Yangon (UTC+6:30)
Kathmandu (UTC+5:45)
New Delhi, Colombo(UTC+530)
Male (UTC+5)
Nairobi (UTC+3)
Cape Town (UTC+2)
Vienna, Geneva (UTC+1)
Sao Paulo (UTC-3)
Washington DC (UTC-5)
Chicago (UTC-6)
Los Angeles (UTC-8)
Honolulu (UTC-10)

Africa - Asia
7pm – 10pm
4pm – 7pm
3pm – 6pm

Asia - America
1pm – 4pm
10am – 1pm
9am – noon

America - Africa
4am – 7am
1am – 4am
0am – 3am

2pm – 5pm

8am – 11am

11pm – 2am

1:30pm – 4:30pm
12:45pm – 3:45pm
12:30pm – 3:30pm

7:30am – 10:30am
6:45am – 9:45am
6:30am – 9:30am

10:30pm – 1:30am
9:45pm – 0:45am
9:30pm – 0:30am

Noon – 3pm
10am – 1pm
9am – noon
8am – 11am
4am – 7am
2am – 5am
1am – 4am
11pm – 2am
9pm – 0am

6am – 9am
4am – 7am
3am – 6am
2am – 5am
10pm – 1am
8pm – 11pm
7pm – 10pm
5pm – 8pm
3pm – 6pm

9pm – 0am
7pm – 10pm
6pm – 9pm
5pm – 8pm
1pm – 4pm
11am – 2pm
10am – 1pm
8am – 11am
6am – 9am

The advantage of a one country programme is the use of a local language that significantly
enhances the understanding of the participants. Although this training package has been developedin English only, all the scripts of the pre-recorded narration are available as texts, which can be easilytranslated into local languages. The most technical part of the programme, which is usually
delivered by international experts who travels to the programme country, is covered by this training
package. The organizers, thus, do not have to find and invite them to provide lectures.

10

Invitation, call for participation
Unless the training is planned for internal people only, e.g., staff training, an invitation or call will be
developed and distributed to relevant parties. A one-page flyer or a concept note is useful andeffective for attracting the attentions of target populations. There are a variety of methods to registerthe participants. One example is provided for reference.

Assessment and evaluation
If a training programme is developed as a part of the project activity, the result monitoring is often
required. Questionnaire surveys are commonly used for self-assessment on many occasions.
Assuming that the programme organizers are not the expert of the issue, this training package
provides a sample questionnaire that can serve as pre- and post-training assessment for theparticipants.

11

3.2 Sample concept note
Background and Objectives
The Minamata Convention on Mercury (the Convention) is one of the newest multilateralenvironmental agreements aiming at protecting human health and environment from anthropogenic
emissions and release of mercury and mercury compounds. In October 2013, the Convention wasformally adopted and opened for signature at a Diplomatic Conference on the Convention convened
in Kumamoto, with a ceremonial opening held in Minamata City in Japan.
The Convention entered into force in August 2017 and the Parties to the Convention must abide by
the provisions stipulated to the Convention text. There is a growing need for capacity building
concerning appropriate mercury monitoring skills in developing countries to ensure theimplementation of the required efforts to monitor the levels of mercury and mercury compounds.
The project implemented by [Name of institution] supports participating countries to improve theirnational mercury-related information base to implement mercury management, especially in theareas of information exchange, awareness and education, research development and monitoring.
The purpose of this training programme is to provide support the enabling efforts for thelaboratories that is monitoring (or will monitor) mercury levels in the country. The programme
addresses different monitoring needs and priorities of each laboratory by providing methodologies
and skills of mercury monitoring in various environmental and biological media.

Participation Details
Date: 01, 02, 03 and 04 July 202X
Venue: Virtual meeting, Webex.
Project title: [Title of project, if any]
Training title: Laboratory management for mercury survey and monitoring
Participants: Public laboratories and laboratories in universities that undertake (or will undertake inthe near future) mercury analysis for monitoring, survey or research purposes. Laboratories which
are able to obtain analytical results by themselves without external resources/supports. No
restriction of number of participants from each institution.
Arrangement: The training programme is composed of 4 sessions in 4 days, which supports theenabling efforts for the participating laboratories. The topic of the training covers general mercury
monitoring and analysis in the environmental and biological media, including several presentations,

12

Q&As, and discussions. Pre- and post-training questionnaire surveys using the online form will be
requested to the participants.
Language: English only (no interpretation provided)13

3.3 Sample training course
This is a sample training course that expects extending basic knowledge on mercury science andprovides hands on skills to the participants who are involved in mercury analysis. There are manyother possible variations and shorter trainings with more focused topics to specific audiences. (The
Lecture and Section numbers below refer to the PowerPoint slides of the presentation material in
Chapter 5)

Configuration
The training course is opened by the organizer with welcome remark and the expectation of the
programme towards achieving the expected impact. The programme is divided into four sessions,in which the following topics are addresses:▪
▪
▪
▪

Session 1: Atmospheric survey analysis
Session 2: Solid and liquid sampling and analysis
Session 3: Human biomonitoring
Session 4: Advancement to qualified laboratory

Session 1 provides a brief overview of mercury issues and the moves onto atmospheric monitoring
techniques using the manual active sampling method. Both field sampling and laboratory analysis
are covered in this session.
▪
▪
▪

Lecture: Properties and environmental behaviour of mercury (extracted from Lecture 1
Sections 1, 2, 6)
Lecture: Atmospheric survey and analysis Part I (Lecture 2 Part I Sections 1-4)
Lecture: Atmospheric survey and analysis Part II (Lecture 2 Part II Sections 1-4)

Session 2 explains mercury monitoring for environmental solid and liquid samples such as soil,
sediment, biota, and environmental water. Some practical tips and skills are provided for field
operators.
▪
▪

Lecture: Solid sample survey and analysis (Lecture 3 Sections 1-7)
Lecture: Water sample survey and analysis (Lecture 4 Sections 1-4)

After the explanation lectures, the participants work individually or in groups for assessing thecurrent capacity and challenges of the laboratories where they work. A self-assessment form
(Chapter 3.4) is provided for the participants to fill so that they understand the required level oflaboratories to produce comparable data. The participants present the finding and assessment
results and feedback is given.
Session 3 addresses human biological media, which is another important set of monitoring items.
Mercury toxicity can be directly evaluated using human samples such as human hair, which is often

14

collected along with environmental samples. This section explains the analytical process of
methylmercury, which is one of the most important indices for assessing mercury risks to humans.
▪
▪

Lecture: Human biological sample analysis (Lecture 5 Sections 1-3)
Lecture: Methylmercury analysis (Lecture 6 Sections 1-3)

Session 4 departs from individual monitoring activities and discusses the way towards qualified
laboratories that contribute to mercury science and management. The first lecture discusses
various monitoring needs in relation to the provisions of the Minamata Convention. Then the next
lecture provides a detailed explanation of quality management to ensure the reliability of analytical
data. Finally, laboratory safety and environmental management are explained to establish a goodlaboratory that not only generates qualified data but also takes care of staff and the environment.
Finally, follow up plan and actions after the training programme are discussed.
▪
▪
▪

Lecture: Mercury monitoring and the Minamata Convention (Lecture 7 Sections 1-5)
Lecture: Quality management (Lecture 8 Sections 1-6)
Lecture: Laboratory safety / environmental management (Lecture 9 Sections 1-5)

Although the sample course does not provide in-depth discussions on cross-cutting issues ongender and human rights, some reference materials are provided to help the participants understandthe importance of this dimension and how it can lead to policy interventions. Adopting an integrated
approach on interconnected issues is crucial towards effective policy measures2.

Programme agenda
Day 1
00:00-00:05(5min)
00:05-00:15(10min)00:15-00:25(10min)00:25-00:45(20min)00:45-00:55

Opening session
Get started – technical set-up, connectivity test, housekeeping
Opening remarks
Session 1: Atmospheric sampling analysis
Introduction
Objectives, expected outcomes and schedule
Lecture: Property and environmental behaviour of mercury
Physical and chemical properties, mercury products and uses, andenvironmental behaviours
Q&A and discussion

Organizer

Organizer
Video (07’43”)

2This is in line with the Minamata Convention on Mercury which notes the Parties’ awareness of ‘healthconcerns, especially in developing countries, resulting from exposure to mercury of vulnerable populations,especially women, children, and, through them, future generations.’ In addition to the health aspects, theConvention further promotes the consideration for the needs of vulnerable populations in health aspects,
public information, awareness and education (Article 18), in research, development and monitoring (Article19), and in effectiveness evaluation (Article 22), are key priorities to be taken forward.

15

(10min)
00:55-01:35(40min)01:35-01:50(15min)01:50-02:00(10min)02:00-01:40(40min)01:40-01:55(15min)02:55-03:00(5min)

Lecture: Atmospheric survey and analysis
Manual active sampling method Part I: sample collection
Q&A and discussion

Video (35’01”)

Break
Lecture: Atmospheric survey and analysis (Continued)
Manual active sampling method Part II: measurement, dataprocessing and QA/QC
Q&A and discussion

Video (26’09”)

Wrap up
Key points of the day

Organizer

Day 2
00:00-00:05(5min)
00:05-00:15(10min)00:15-01:05(50min)01:05-01:20(15min)01:20-01:30(10min)01:30-02:10(40min)02:10-02:25(15min)02:25-02:55(30min)02:55-03:00(5min)

Session 2: Solid and liquid sampling and analysis
Get started – technical set-up, connectivity test, housekeeping
Introduction
Introduction of Session 2
Lecture: Solid sample survey and analysis
Soil, sediment, and biota sample collection and analysis
Q&A and discussion

Organizer
Video (40’21”)

Break
Lecture: Water sample survey and analysis
Water sample collection and analysis
Q&A and discussion

Video (28’02”)

ExerciseLaboratory capacity self-assessment
Wrap up
Key points of the day

Facilitator
Organizer

Day 3
00:00-00:05(5min)
00:05-00:45(40min)00:45-00:55(10min)00:55-01:25(30min)16

Session 2 (continued)
Get started – technical set-up, connectivity test, housekeeping
Report back
Results of Exercise by each group including discussion
Session 3: Human biomonitoring
Introduction
Introduction of Session 3
Lecture: Human biological sample analysis
Human biological sample (hair, blood, and urine) analysis

Facilitator

Organizer
Video (20’10”)

01:25-01:40(15min)01:40-01:50(10min)01:50-02:10(20min)02:10-02:25(15min)02:25-02:45(20min)02:45-02:55(10min)02:55-03:00(5min)

Q&A and discussion
Break
Lecture: Methylmercury analysis
Methylmercury analysis, simplified analysis for human hair
Q&A and discussion
Session 4: Advancement to qualified laboratory
Lecture: Mercury monitoring and the Minamata Convention
Contribution of mercury monitoring to the Minamata Convention
Q&A and discussion
Wrap up
Key points of the day

Video (11’27”)

Video (18’28”)

Organizer

Day 4
00:00-00:05(5min)
00:05-00:15(10min)00:15-01:15(60min)01:15-01:30(15min)01:30-01:40(10min)01:40-02:10(30min)02:10-02:25(15min)02:25-02:50(25min)02:50-03:00(10min)Session 4 (Continued)
Get started – technical set-up, connectivity test, housekeeping
Introduction
Introduction of Session 4
Lecture: Quality management
QA and QC, SOP and record, bias and uncertainty
Q&A and discussion

Organizer
Video (47’22”)

Break
Lecture: Laboratory safety / environmental management
Safe laboratory operation, environmental management
Q&A and discussion

Video (21’49”)

Discussions
Towards a qualified laboratory – plan and action
Wrap up and closing
Way forward

Facilitator
Organizer

173.4 Laboratory capacity self-assessment
In the training programme, the laboratory capacity assessment can be done individually or in groups
belonging to the same laboratory. Data collection items can be announced prior to the training sothat most of the time can be allocated to the analysis and discussion of the information.

Basic data▪
▪
▪

Name of laboratory
Organization and Department
Country

Self-assessment items
Sample media and parameters
Q1: How many sample analyses do you conduct in a year?
Experience
RoutinelyMedia

Parameter

Number of samples per year

Conducted in
the past
Futureplanning

Personnel and organization
Q2: How many staff are there in the laboratory?
Q3: Regarding the staff, how many years of experience in environmental survey/analysis do they
have? (Individual information, if possible, otherwise the average for all staff)
Q4: Are there documented or undocumented periodic training programmes for the staff?

Laboratory workspace
Q5: Please provide the approximate floor area of the laboratory space for mercury or other heavy
metal analysis.

18

Methods and procedures for the analysis
Q6: Which manuals do you follow for sampling and laboratory analysis?
Media

Parameter

ManualQ7: Are there documented standard operating procedures (SOPs) for survey / sampling? (ifperformed)
Q8: Are there documented SOPs for sample preparation?
Q9: Have the records of sampling (if performed) and laboratory analysis been kept?
Q10: Are uniform record formats prepared for sampling (if performed) and laboratory analysis?

Sample management and storage
Q11: Is the sample managed using a unique sample code (ID)?
Q12: What are the conditions of sample storage (e.g.: stored in a sample storage room at room
temperature, stored in a refrigerator (4 °C), stored in a freezer (-20 °C))?
Q13: Are there documented SOPs for sample management and storage?
Q14: Have the records of sample transportation and storage been kept?

Laboratory facilities
Q15: Is the laboratory room controlled for mercury or other trace element analysis? (e.g., thelaboratory room is a cleanroom, the room is used only for trace element analysis, the room is used
only for water analysis and not for soil, waste, or other high concentration samples, etc.)
Q16: What are the power supply conditions? (e.g., good, sometimes unstable voltage, sometimes
blackouts, etc.)

Laboratory apparatus and reagents
Q17: How many samples can be analysed in a single operation? (i.e., maximum number that can betreated in a single batch, etc.)
Q18: Which grade of reagents do you use? (e.g., reagent grade, trace element analysis grade, ultratrace analysis grade, etc.)19Q19: Are there any reagents that are difficult to purchase? (e.g., there is no provider in the country,
legal permission is required, etc.)
Q20: What are the storage conditions of the reagents? (e.g., stored in the analysis room, stored in alocked chamber, stored in a refrigerator, etc.)
Q21: Is the usage of reagents managed? (Are date and time of usage recorded?)
Q22: Is the quality of the reagents (e.g., blank amount, interference substances, etc.) checked? (e.g.,
it is checked before a new provider’s product or new production lot is used.)
Q23: Are there SOPs for reagent management?
Q24: Have the records of reagent use been kept? (e.g., date of opening, start and end date of usage,
etc.)
Q25: What type of water do you use for analysis? (e.g., distilled water, ion exchanged water, filteredwater, combined with these purifications, purchased pure water, etc.)
Q26: Is the measuring equipment (e.g., balance) traceably calibrated to national or international
standards?
Q27: How apparatus for analyses are washed and stored? (e.g., washed with ultrasonic, soaked in
HNO3 solution during storage, rinsed with deionised water just before use, etc.)
Q28: For QA/QC analysis, is the reference material (RM) or certified reference material (CRM) of asimilar material to the sample? (e.g., soil, hair, fish, etc.)
Q29: If yes, which type of RM/CRM? (e.g., product name, media, chemical form, provider, etc.)

Measuring instruments
Q30: What instruments do you use for analysis? (Not limited to mercury analysis)
Q31: What is the condition of the instruments? (e.g., good, something malfunctioning, overhaul
maintenance has not been carried out for a long time, etc.)
Type of instrument (e.g., CVAAS, ICP-OES)

Number of
Instrument

Condition of instrument

Q32: What is the condition of manufacturer service and supply of parts, and are there difficulties ingetting parts supplied? (e.g., good, need a long time to be supplied, etc.)20Q33: What is the status of maintenance service and the estimated downtime when the instruments
have mechanical troubles? (e.g., you receive maintenance service from the provider quickly, it takes
a long time since there is no technical person (or provider) in the country, etc.)
Q34: Are there SOPs for operation, daily checks and maintenance?
Q35: Have the records of measurements been kept?

Quality assurance / quality control (QA/QC)
Q36: What types of QA/QC analysis are performed? (e.g., field blank, operation blank,
multiple(duplicate) analysis, instrumental sensitivity check, recovery analysis, CRM analysis)
Q37: Has the limit of detection (LOD) of the analysis in the laboratory been estimated?
Q38: Has the uncertainty of the analysis in the laboratory been estimated?
Q39: Is the Laboratory Information Management System (LIMS) installed?
Q40: Do you periodically participated in international studies or the proficiency tests?

Environmental management
Q41: Are there fume hoods/exhaust chambers for toxic exhaust gas?
Q42: Is there gas treatment equipment (e.g., acid gas scrubber, etc.) in the fume hood/exhaustchamber?
Q43: How is wastewater treated? (e.g., treated in the laboratory and drained with municipal water,
stored and entrusted to a waste treatment company, treated at a water treatment facility of the
facility, treated at wastewater treatment facility of the city, etc.)
Q44: How is the solid waste treated? (e.g., entrusted to a waste treatment company, etc.)
Q45: Has the ISO 14001 certification been accredited?
Q46: Are there documented SOPs for laboratory environmental management? (wastewater/solid
waste management, etc.)
Q47: Are there documented SOPs for laboratory safety management?

Analysis and discussion▪

Formulation of medium to long-term future plans for mercury survey and analysis.

21

▪
▪
▪
▪

22

Plans (including procurement plans) for facilities and equipment for analysis.
Securing and training of personnel.
Development of a quality management system.
Participation in interlaboratory comparison (e.g., proficiency testing), information exchangewith other institutions, etc.

3.5 Pre- and post-training self-test andevaluations
It is important to collect information from the training participants to ensure the participation oftarget audiences and to assess the effectiveness of the programme. It should be disaggregated bygender and age range when a questionnaire is analysed.

Full-registration questionnaire<Personal information> (all mandatory)
▪
▪
▪
▪
▪
▪

First name
Family name
Gender (single choice): Male, Female, Prefer not to tellAge range (single choice): 19 or below, between 20-29, between 30-39, between 40-49,
between 50-59, 60 or above
Country / Region
Email<Work-related information> (all mandatory)
▪
▪
▪

▪

Name of Institution:
Position in Institution:
Your role(s) in the institution (Select all that apply to you): Management, administrative
work, policy development and implementation, education and lecture, sample/specimen
collection and analysis, research planning and experiment, machine operation andmaintenances, data processing and analysis, consulting, public relation andcommunications, student, other (please specify)
How much of your routine work relates to mercury (single choice): Less than 10%, between
10-50%, more than 50%<Baseline survey for progress monitoring>:
Please respond to these questions based on your own personal knowledge (this is NOT an exam!)

Q1: Have you ever carried out mercury analysis in the following media? (Select all that apply to you).
▪
▪
▪
▪

Water: ☐drinking water, ☐environmental water, ☐groundwater, ☐wastewater
Air: ☐ambient air, ☐exhaust gas
Soil: ☐natural soil, ☐contaminated soil including solid waste, ☐sedimentFood: ☐fish, ☐shellfish, ☐crops and vegetables, ☐other please specify

23

▪
▪
▪

Human: ☐hair, ☐blood, ☐urine, ☐other please specify
Products: ☐battery, ☐lamp, ☐agricultural chemicals, ☐pharmaceutical products,☐cosmetics, ☐any other product please specify
Wildlife: ☐ please specify

Q2: Do you know the differences between elemental mercury and methylmercury in the following
areas? (Select all that apply to you).
▪
▪
▪
▪
▪

☐Physical property,☐Biological property,☐Toxicity,☐Environmental behaviour,☐Source of generation

Q3: Are you able to explain why mercury is used in the following products and processes?
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪

Battery: ☐Yes thoroughly, ☐to some extent, ☐not reallyLamp: ☐Yes thoroughly, ☐to some extent, ☐not really
Vaccine: ☐Yes thoroughly, ☐to some extent, ☐not really
Switch: ☐Yes thoroughly, ☐to some extent, ☐not reallyDental restoration: ☐Yes thoroughly, ☐to some extent, ☐not really
Thermometer: ☐Yes thoroughly, ☐to some extent, ☐not really
Sphygmomanometer (manometer): ☐Yes thoroughly, ☐to some extent, ☐not really
Vacuum pump: ☐Yes thoroughly, ☐to some extent, ☐not really
Tire balancer: ☐Yes thoroughly, ☐to some extent, ☐not really
Photographic film and paper: ☐Yes thoroughly, ☐to some extent, ☐not really
Propellant for satellites: ☐Yes thoroughly, ☐to some extent, ☐not really
Chlor-alkali production: ☐Yes thoroughly, ☐to some extent, ☐not really
Vinyl-chloride production: ☐Yes thoroughly, ☐to some extent, ☐not really

Q4: Can you explain the mercury detection theory in cold vapour atomic absorption spectrometry?
▪

☐Yes thoroughly, ☐to some extent, ☐not really

Q5: Can you properly select and design the monitoring methodology for the following surveys?
▪
▪
▪

24

Mining site: ☐Yes thoroughly, ☐to some extent, ☐not really
Waste-dumping site: ☐Yes thoroughly, ☐to some extent, ☐not really
Vulnerable population: ☐Yes thoroughly, ☐to some extent, ☐not reallyQ6: Can you differentiate the blood, urine and hair testing for assessing human health risks due tomercury exposure?
▪

☐Yes thoroughly, ☐to some extent, ☐not really

Post-training evaluation questionnaire
Each answer should be linked with the registration information so that the personal attributes canbe used for statistical analysis.

<Personal information> (all mandatory)▪
▪
▪
▪

First name
Family nameCountry / Region
Email< About the training programme >Q1: Could you rate the overall level of the presentations that you received in comparison with yourpersonal competency?
▪

☐Too high, ☐slightly high, ☐just fit to me, ☐slightly low, ☐too low

Q2: Could you select one presentation/topic that interests you the most? (Single choice)(List all presentations or topic here)

Q3: Who do you think was the most suitable people/section in your institution to participate in thistraining programme? (Select all that apply to you).
▪

☐Myself, ☐my co-workers, ☐ specific section of the institution (please specify), ☐no one
in my institution

Q4: What will you do with the information received in this training programme? (Select all that apply
to you).
▪

☐Apply it to my daily work, ☐share it to my colleagues and others, ☐ask UNEP for
more/specific information, ☐ other (please specify), ☐none at this moment

25

Post-training evaluation for progress monitoring
These questions are asked to measure the contribution of the training programme for developing
capacity. The numbers are respective to the baseline survey for progress monitoring done prior to
the training.

Q2: Do you think the programme helped to improve your understanding on the difference between
elemental mercury and methylmercury in the following areas? (Select all that apply to you).
▪
▪
▪
▪
▪

☐Physical property,☐Biological property,☐Toxicity,☐Environmental behaviour,☐Source of generation

Q3: Do you think the programme helped your understanding why mercury is used in the following
products and processes?
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪
▪

26

Battery: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me,☐ the item was not relevant in this programme
Lamp: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me, ☐the item was not relevant in this programme
Vaccine: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me,☐ the item was not relevant in this programme
Switch: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me,☐ the item was not relevant in this programme
Dental restoration: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme
Thermometer: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing
to me, ☐ the item was not relevant in this programme
Sphygmomanometer (manometer): ☐ Helped a lot, ☐helped to some extent, ☐nodifference, ☐more confusing to me, ☐ the item was not relevant in this programme
Vacuum pump: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing
to me, ☐ the item was not relevant in this programme
Tire balancer: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing
to me, ☐ the item was not relevant in this programme
Photographic film and paper: ☐ Helped a lot, ☐helped to some extent, ☐no difference,☐more confusing to me, ☐ the item was not relevant in this programme
Propellant for satellites: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme
Chlor-alkali production: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme▪

Vinyl-chloride production: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme

Q4: Do you think the programme helped you to understand the mercury detection theory in cold
vapour atomic absorption spectrometry?
▪

☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me, ☐ theitem was not relevant in this programme

Q5: Do you think the programme helped you to be able to properly select and design the monitoring
methodology for the following surveys?
▪
▪
▪

Mining site: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing tome, ☐ the item was not relevant in this programme
Waste dumping site: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme
Vulnerable population: ☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more
confusing to me, ☐ the item was not relevant in this programme

Q6: Do you think the programme helped you to differentiate the blood, urine and hair testing forassessing human health risks due to mercury exposure?
▪

☐ Helped a lot, ☐helped to some extent, ☐no difference, ☐more confusing to me, ☐ theitem was not relevant in this programme273.6 Frequently Asked Questions
In the course of the training programme, participants will ask questions to deepen theirunderstanding. Some responses made by the lecturers about this lecture materials in the pasttraining programmes are compiled here for future reference. Similar questions can be addressed in
the same way so that the messages conveyed to the participants will be consistent.

Laboratory management
Question
1. What are the major risks andopportunities of a mercury testinglaboratory?
2. Could you please specify the
primary treatment for laboratory
wastewater contaminated withmercury?
3. Why is it not necessary to have
ISO 14001 accreditation? Is theaudit not necessary?

28

AnswerOne opportunity for the laboratory is the high value of the data. Highquality data can lead to find new facts. On the other hand, a risk canbe the misinterpretations of the surveys/experiments due to low
quality data.
Activated carbon can be used as a way to remove mercury fromwastewater. However, since the efficiency and characteristics oftreatment methods differ depending on factors such as theproperties of the wastewater and coexisting substances, thetreatment method must be thoroughly examined in advance.
Official ISO 14001 certification with audit is effective since it
confirms defects that are not noticed by the laboratory itself. But it iscostly. Even if there is no official certification, operating anenvironmental management system with reference to therequirements of ISO 14001 is very effective for environmental
management during the accreditation period. The benefit of ISO
14001 management system without certification is also described in
the ISO publication.

Quality control and assurance
Question
1. For testing laboratory, is
ISO/IEC 17025 best standard
rather than 14001?
2. How often do reagent blanks
need to be performed?

3. Can the samples forinterlaboratory comparison be
used as control samples for thelaboratory analysis?
4. What do 3s and 10s mean for
limit of detection, LOD, and limitof quantification, LOQ?

5. In reporting, which is better, thestandard error of the mean orsimply the standard deviation?
6. Please explain in detail
rectangular and triangular
distributions.

AnswerISO/IEC 17025 is focused on procedures for the quality management
systems for testing laboratories. However, testing laboratories should
also be managed under environmental management, thus ISO 14000
standards are helpful for the environmental management oflaboratories.
A reagent blank should be confirmed prior to the first usage of thereagent. When the type of reagent (such as provider, or grade) ischanged, its blank should be confirmed again. Even if an operation
blank is analysed on every analysis, periodical tests of reagent arerecommended. When a large operation blank is found, each reagent
used in the analysis should be checked to find the source of theblank.
Yes, remaining interlaboratory testing samples are also goodreference materials for QA/QC.
Assuming the probability of the analysis is following normal
distribution, 99.7% of the results are expected to fall within the 3s
range. When 3s is defined as the LOD, it is the level that the analysis
results are deemed appropriate (i.e., a difference can be clearlyshown). Of course, in this case, it is necessary to separately verify
that the measuring device can reliably detect the numerical value of
3s (the signal can be separated from the background). As for the
LOQ, the meaning of 10s cannot not be clearly explained, but it is one
way to consider that 10s is sufficient level to treat the analyticalresults statistically. The LOD/LOQ of 3s and 10s is described in somemanuals (not limited to the Japanese manual for the mercury
analysis). One of the advantages is that it can be easily calculated.
Basically, the test instructions must be followed. The standard
deviation of the results represents the uncertainty in each analysis,
while the standard error of the mean represents the uncertainty of thereporting value (mean), so they have different meaning.
Triangular and rectangular distributions are used for uncertainty
estimation of the type B approach. For estimations of type A, theuncertainty is estimated from the standard deviation of the multiple
experiment of the measurement. In many cases of the type B
analysis, the actual uncertainty is unknown (e.g., the pipette, which is
assigned, is the only guaranteed value, not an uncertainty). In suchcases, the probability distribution of the value to estimate theuncertainty should be assumed. If the probability distribution of thevalues is expected to be similar to the normal distribution, atriangular distribution is considered to represent the actual
distribution. If the values are considered to be distributed almost
evenly within the guaranteed values, a rectangular distribution ismore suitable.

29

Survey plan and sampling
Question
Air monitoring
1. What is the JIS code for an air
monitoring method?
2. Is the sampling method
traceable to other official
standards like ISO?

3. What is the detection limit ofthis manual method?
4. Is the toolbox shownstandard, or an equivalentdevice can be used?
5. The method of the USEPA(chapter IO-5) uses 2 gold
cartridges. What is thedifference between using 1 trap
and 2 traps?
6. For a duplicate or triplicate
sampling, does each tube haveits own pump? How do you
troubleshoot the problems withpump?
7. How is the gold
amalgamation cartridgecleaned? Are there any kits or
products available in themarket?
8. What type of tubing can beused?
9. What is the requirement ofsoda lime in the sampler inlet?
Does it interfere with themercury concentration?

30

Answer
The manual is published by the Japanese government, but it is not in
the JIS series.
The sampling method explained in the lecture is from the manual of
the Japanese method, which does not fall under or related to the ISO
method. It is not possible to make a reference for data validation withthis method, but it is a well-established methodology reviewed
thoroughly by the technical committee during the preparation process.
A draft English translation of the manual of the Japanese method isavailable on the website of the Minamata Convention. (MOEJ (2004).
Mercury analysis manual, March 2004.).
It depends on the measuring instrument, but in the condition of thelecture (0.5 L/min and 24-hour sampling, CVAAS measurement), theLOD is usually lower than 0.1 ng/m3. This LOD is much lower than theatmospheric mercury concentration in the background area.
The device in the toolbox is not a standard, and can be built from theindividual devices (e.g., pumps, tubing, and thermometer) available on
the market. Other types of devices such as pumps having sufficientperformance is available.
The second gold cartridge described in the USEPA method IO-5 is used
to confirm the break-through of mercury from the first cartridge.
Basically, the procedures of this lecture’s method (based on theJapanese manual) and the IO-5 method are the same.
When multiple gold cartridges are connected to the same pump, not all
cartridges have the same flow rate. Thus, one pump is necessary foreach gold cartridge. In the case of pump malfunction, pumps arenormally replaced or fixed by the manufacturers.
There are no products only for cleaning the gold amalgamation
cartridge sold in the market. However, mercury collected in the gold
amalgamation cartridge is purged out during the measurement.
Therefore, the gold cartridge is simply cleaned by measuring it. To
confirm whether the gold amalgamation cartridge is well cleaned, thegold cartridge can be used for measurement once more (thismeasurement can work as a re-clean-up of the gold cartridge).
During sampling, tubing is used downstream of the gold cartridge, sothat tubing has little effect on sample collection. Therefore, many typesof tubing can be used as long as they are clean and have no leakage.
The soda lime is composed of lime and some alkali such as sodiumhydroxide. The soda lime absorbs the gaseous oxidized mercury(GOM) in the air. However, since the atmospheric GOM concentration inambient air is so small, it has little effect on the total concentration of
atmospheric mercury. Soda lime has no other effect on the sampling
and measurement of mercury in the atmosphere. The detailed processof removing the interfering substances is still unknown, but theinterfering gaseous substances such as SOx, NOx are effectively
absorbed by the alkaline in soda lime.

Question
10. What brand/purity of soda
lime is recommended? How is it
cleaned?
11. Please provide more details
regarding the particle filter.
12. Is there any specific periodic
flow rate during the 24-hourmonitoring?
13. What is the relationshipbetween the flow rate andmercury sampling at 0.5 L?
14. In case of high Hgconcentration, can we reduce
sampling time or flow rate? For
example, can we reduce to theduration to 4 hours? How muchconcentration can beconsidered as high?

15. How the sampling volume
can be changed by flow rate or
any other means?

Solid monitoring
16. Is there any potential risk ofbias when using metal tools
during field sampling?

Answer
The ideal soda lime composition is still under research, but many ofsoda limes which are commercially available can be used. However, itis necessary to check the mercury blank before the first use. If a blankis detected, the blank can be reduced by heating the soda lime at ahigh temperature (about 250 °C).
In this lecture, a membrane filter with 0.45 micrometre pore size isused. However, to remove the serious interference of particle matter in
the air, several types of filters which do not contain mercury, and do notabsorb atmospheric mercury can be used.
There is no specific flow rate. However, the Japanese manual requires
0.1-0.5 L/min of flow rate for 24-hours sampling. To avoid deviationfrom the diurnal variations at the survey site, 24-hours sampling is
recommended to obtain the general situation of the site.
In most cases, there is a linear relationship in the range from around
0.1 L/min to 1 L/min. The sampling amount should be changed when
the concentration is expected to vary. In such cases, the sampling
amount can be changed with the flow rate of above range or sampling
duration.
In general cases, the LOD of the method is lower than 0.1 ng/m3 for 24hour sampling. In most of the general background situations,
atmospheric mercury concentration is around 1 ng/m3 (in southernhemisphere, there are cases where the concentration is somewhat
lower). Thus, 3 hours or more sampling can be done when the mercury
concentration is larger than the LOD. However, the relative uncertaintyof the results usually becomes larger when the amount (notconcentration) of mercury is very small. The calibration standard of themeasurement should cover the expected mercury amount range. Also,
when the sampling duration is decreased to shorter than 24 hours, it
should be noted that the data may be affected by the diurnal variationof the concentration.
Sampling flow volume can be changed to suit the objective andsituations of the survey. For example, sampling in the highatmospheric mercury concentration areas, a smaller sample volume issufficient to analyse the concentration. Sampling volume can bechanged both by changing flow rate and sampling duration. The
Japanese manual prescribes the flow rate to be between 0.1 - 0.5
L/min. With a very small flow rate, it becomes difficult to measure theaccurate flow volume. On the other hand, with very large flow rate
(such as over the 1.0 L/min), the mercury collection rate by a gold
cartridge may be low.
Strictly speaking, metal sampling tool may affect the mercury
concentration of the sample. However, considering the concentrationlevel of the soil/sediment samples and the areas of contact between
the tools and samples, the effect of metal (steel) tools for solid sample
is usually small. Nevertheless, those metals, which create amalgam
with mercury, such as copper or aluminium, should be avoided. For thewater samples, because of its low concentrations, metal tools should
be avoided.

31

Question
17. Are there any differences inthe distribution of
methylmercury depending on
the fish species?
18. How can we assure therepresentativeness of muscles
sampling?
Water monitoring
19. Are there any othermethodology for long-timestorage of water samples? Is it
sufficient to add HCl?

Biomonitoring
20. If we make a study about theeffect of mercury on people andtheir habits, which sample isbetter, hair, nail or urine?

21. Normally what is the ratio of
inorganic mercury tomethylmercury in the humanbody? Which type of mercury(inorganic or methyl) is more
toxic?

32

Answer
The distribution tendency of methylmercury in the organs does notdiffer greatly between different species. But there may be a slightdifference in some species due to their metabolic systems.
In general, there is not much difference in mercury in the muscle tissue
of same organism, but some concentration differences from site tosite. It is recommended to homogenize the entire muscle of thesample to ensure sufficient homogeneity.
(Inorganic) mercury in water is rather unstable and easily volatilized.
Freezing is a good method for long-time storage, but it may not be easy
to use freezers to keep many water samples since water samples areusually bulky. Stabilisation with bromine monochloride (BrCl) is
effective to stabilise mercury in water. In many cases, BrCl added(usually about 0.5 %) water samples can be stored for a month or
more. However, BrCl is a hazardous reagent and should not be used at
the sampling sites. To stabilise water samples with BrCl, the samples
are brought back to the laboratory before adding BrCl.

Sampling should be selected in consideration of the objective of thesurvey. If the most important exposure of the subject people isexpected to be methylmercury from the food, hair is a good sample. To
obtain the information of elemental (gaseous mercury) or inorganic
mercury exposure, urine is a good sample. Nail is also a good indicatorfor methylmercury exposure although only few research reports areavailable. The nail samples have advantages such as less customary
resistance of the participant to sampling and relatively less external
influence than hair (mercury concentration in hair may be affected bybreaching, permanent waves, personal care products, etc.).
Except the people who are living in the area of high concentration of
atmospheric mercury (such as ASGM), most mercury exposure ismethylmercury from food, and most mercury in the bodies of general
population is methylmercury. In terms of the biological half-life andtoxicity, methylmercury is more serious than inorganic mercury.
However, gaseous elemental mercury (GEM) is inhaled from the lungs,
and a high concentration of GEM seriously affects the nervous
systems. Therefore, a very high concentration of GEM is also very toxic,
although such situation hardly occurs except for rare occasions suchas the situation described above. Methylmercury in the human body is
excreted in faeces, Also, some methylmercury is accumulated in hair orchanged into inorganic mercury and excreted to urine.

Question
22. What can be expected fromthe result of total mercury
analysis of the human hair? Can
the results provide information
on exposure to elemental or
inorganic mercury?

23. Should the subject person
refrain from dying the hair?

24. Is there any effect on the
mercury concentration if metal
scissors are used for hairsampling?
25. What percentage of total
mercury is methylmercury?

26. How can the results of total
mercury and methylmercury becompared? Is there any
commonly known large
difference in concentration?

AnswerAlmost all mercury in hair is methylmercury as a result of themetabolism in the body. Although very little elemental and inorganic
mercury accumulates in hair, when the subject person is exposed ahigh amount of elemental or inorganic mercury (e.g., under the highgaseous mercury environment, using mercury added personal careproduct), elemental or inorganic mercury may adhere to the surface of
hair. Even though a quantitative evaluation is difficult, information of
exposure of such elemental or inorganic mercury can be obtained fromtotal mercury analysis. However, to distinguish the methylmercury
exposure, methylmercury analysis of hair sample is required in addition
to total mercury analysis.
In practice, it may be difficult to restrict the activity of the subject
person, but hair treatments affect the mercury concentration in hair(bleaching and permanent waves treatment have a relatively large
effects). Adding information about these hair treatments to thequestionnaire for the subject person is valuable when analysing theresults.
If only mercury is to be analysed, the use of metal scissors has virtuallyno effect on the sample. However, they should be washed and dried
well before use.
Methylmercury predominates in living organisms due tobiomagnification and the difference in half-life in the bodies. Most
mercury in the muscle tissues of living organisms is thought to be
methylmercury, but several reports have found considerable amounts
of inorganic mercury. Most mercury accumulated by metabolism inhuman hair is methylmercury, but elemental mercury and inorganic
mercury can adhere to the surface of hair due to the influence of theparticipant’s living environment or the use of mercury-added product.
Methylmercury is especially toxic compared to other chemical forms of
mercury (except dimethylmercury, but its concentration in theenvironment is very low). Therefore, the actual concentration of
methylmercury provides very important information. The objective of
methylmercury analysis is to correctly analyse the exposure status andthe toxicity as the human food. For biota samples, most mercury in themuscle tissues is methylmercury. However, some reports have foundconsiderable amounts of inorganic mercury in the muscle tissues. The
organs such as the liver may have some amount of inorganic mercury.

33Analytical processes
Question
Methodology
1. Is it possible to measure total
mercury in hair sample by
CVAAS?
2. On the measurement of
reduction aeration CVAAS, mustthe mercury vapour from thereaction chamber is purged into
the absorption cell of the CVAAS
assembly be dried or not?
3. Which concentrations areusually reported for soil andsediment samples, wet-based or
dry-based?
Reagent and gas
4. For the sample preparation byacid digestion, can other oxidizing
agents be used to complete
oxidation in addition to theprescribed acid solutions?
5. For the reduction aeration
CVAAS measurement, is it
preferable to use 0.1 % sodium
borohydride instead of stannous
chloride?
6. For the gold amalgamation trap
measurement, can the mercury
standard solution be used forcalibration instead of thestandard mercury gas?
7. For the gold amalgamation trap
measurement, can we use otherinert gases instead of air pump tocarry mercury vapour into the AAS
instrument?
8. For the reduction aeration
CVAAS measurement, can otherinert gases such as argon be
used as a carrier gas instead ofair?
Preparation
9. Before the hair is cut into small
pieces, must it be cut
approximately 3 cm from thebase of hair?

34

AnswerYes, hair sample can be measured by methods such as aciddigestion-CVAAS or thermal decomposition CVAAS. Although theamounts of hair samples are small, sufficient data can be obtainedsince the concentrations of mercury in hair are higher than those inother human organ samples such as blood.
Too much moisture should be avoided to be introduced into themeasurement cell, however, the measurement gas purged from thereaction vessel does not need to be completely dried. The instrumentused in this lecture traps moisture with the cold trap.
It depends on the objective of the survey. For example, the provisionalremoval standard of the sediment in the Japanese legislation is drybased.

Even though most soil, sediment or biota samples can be easily
digested by reagents such as nitric acid, hydrochloric acid andsulphuric acid as mentioned in the lecture, other oxidizing agents canbe used. However, the following items should be kept in mind: 1)
there are cases where mercury in the digested solution volatizes evenin the presence of oxidizing agents. 2) The reagents having highoxidization voltages prevent reduction during the measurement.
Yes, sodium borohydride can be used to create mercury hydride.
Some types of the CVAAS instruments in the market uses this
hydride generation system.
The standard solutions can be used to calibrate for the atmosphericmercury measurements using a closed apparatus and a reducing
agent such as stannous chloride. Further explanations are provided
in the lecture materials.
Yes, alternative inert gases such as nitrogen gas or air may be used ifthey contain no traces of mercury. Mercury free air is probably thecheapest option. However, if the flow rate of the gas is changed
during the measurement operation, the mechanics of the measuring
device may be complicated.
Although argon gas or other inert gases can be used, they are noteasy to use in the CVAAS instrument explained in this lecture
because there is a process of closed circulation.

Collected hair samples should be cut to a length that fits theobjective of the survey before mercury analysis. Since human hairgenerally grows about 1 cm per month, cutting 3 cm from the root
allows the evaluation of the exposure environment of the subject
person for the past 3 months.

Question
10. How can the urine samples beanalysed to obtain accurate
result?

11. Apart from hair samples, howshould other biota samples suchas fish muscles be dried, in anoven or freeze dried?

Methylmercury analysis
12. It is a long procedure. What is
the recovery rate?
13. Are there any quick qualitative
methods for methylmercury inbiological samples?

14. Is the concentration process
required before injection into the
GC instrument?
15. Can the polypropylene
centrifuge tubes be used for thedithizone-extraction GC/ECD
method?
16. What kind of column is used?

17. Are the reagent grade
solvents sufficient? Does it needto have a GC grade?

AnswerIn some cases, the analytical result of urine samples may have lower
accuracy. As mercury in urine samples (mostly oxidized mercury) is
easily volatized, stabilization of mercury during storage and analysis
is important. Urine samples should be frozen before analysis. If it is
not possible, analysis should be conducted immediately after sample
collection.
This method can be used for normal wet samples such as fishmuscle tissues. However, the samples with very high moisture
content may require moisture removal. Freeze-drying is a good
method in terms of stability of methylmercury in the samples andsample handling during analysis. It is possible to dry in an oven, but
the drying conditions such as temperature and time should beconsidered.
Although it is a long procedure, the recovery of mercury using thismethod becomes quite steady and almost 100% recovery of
methylmercury is possible.
There are some other methods for methylmercury analysis. Also,
some research reports suggest simpler analysis methods. Suchmethods can be used, but the key features of such methods (e.g.,
data uncertainty, interfering substances on analysis, LOD) should be
carefully considered to confirm that the objective of the survey canbe fully met.
In this method, sample solution is prepared in a volume of (usually)
0.5 mL by liquid-liquid extraction. No additional concentration
procedure is needed.
From the viewpoint of the methylmercury blank, polypropylene
usually has little effect. However, it is recommended to avoid
polypropylene tubes for dithizone extraction method, because
toluene may dissolve the interfering organic substances from thetube.
In the method explained in the lecture, a packed GC column is used.
Following the description of three types of GC columns in “Mercury
Analysis Manual”, either type of columns can be used for the
analysis:- 3.0 mm × 0.75-1.0 m glass column packed with Hg-20A on
Uniport HP (AW-DMCS, 60-80 mesh, GL Science Co., Ltd.,Tokyo, Japan).
- 3.0 mm × 0.75-1.0 m glass column packed with 10 % KOCLHg on Chromosorb W (AW-DMCS, 60-80 mesh, J-Science Co.,
Ltd., Kyoto, Japan).
- 3.0 mm × 2.0 m glass column packed with 5-10 % polydiethylene glycol succinate (DEGS) on Chromosorb W (AWDMCS).
After packing the column, approximately 2-3 cm of NaCl, previously
heated at 500 °C for 2-3 hours, in packed on top of the packing
material (at the injection port).
Although precise comparisons have not yet been carried out, many
reagent grade solvents are available. However, checking the reagent
blank is necessary before using for the first time (it must be done
either for the reagent grade or GC grade).

35

Question
18. Is the analytical method done
parallel with the standards? What
are the forms of standards?

XRF analysis
19. Can the XRF be used for the
direct soil sampling during thescreening process?
20. Dental amalgam generally
contains about 40-50 % of
mercury. Can it be measured
using XRF?
21. How can dental amalgam
samples be digested?

36

AnswerYes. In this method, the analytical procedures are also performed forthe standard solutions for calibration curve (from sample preparation
to GC/ECD measurement). Prepared methylmercury solutions or
standard solutions on the market can be used, as well as the CRM of
methylmercury that has similar characteristics to the samples areapplicable.
Yes, XRF can measure the samples directly, hence XRF can be used
for direct measurements of unprepared samples. However, mercury
added products such as batteries need to be disassembled so thatthe particular parts can be measured, as mercury is intentionallyadded.
Yes, XRF is a good method to measure dental amalgam. As most ofother analysis methods are focused on much lower mercury
concentrations than that of dental amalgam, a dilution with a large
ratio is necessary during the sample preparation. However, it should
be noted that the measurement results by XRF have a relatively large
uncertainty due to the difference in the characteristics of the sample.
Since dental amalgam is composed of a mixture of silver, tin, zinc,copper, and mercury, it is easily digested by oxidizing acids. However,most analysis methods for mercury using CVAAS are focused tomeasure mercury concentration in the nanogram orders. Whileapproximately a half of dental amalgam is mercury, a ridiculously
small amount of dental amalgam must be used, or very large ratio of
dilution is necessary, if the CVAAS method is used. For the analysis
of dental amalgam, other methods such as XRF may be moresuitable.

4 SUPPLEMENTARY INFORMATION AND
LITERATURE
Background and in-depth information are compiled in this chapter. The users can refer, as necessary,to the material to add value to their own training programme. Some information is slightly beyond
the scope of this training package, but it will serve as a guidance for extended self-study.

4.1 Outlines of the Minamata Convention
on Mercury
The Minamata Convention on Mercury is a multilateral legally-binding environmental agreement
aiming to protect the human health and the environment from anthropogenic emissions andreleases of mercury and mercury compounds. The text was adopted in October 2013, and iscomposed of a preambular text, 35 articles, and 5 annexes. The Convention entered into force on
16th August 2017, on the 90th day after the deposition of the 50th instrument of ratifications,
acceptance, approval, or accession.
In its preamble, the Convention recognises the substantial lessons of Minamata disease, inparticular the serious health and effects resulting from the mercury pollution, and makes aware of
the health concerns to women, children, and future generation. The Convention sets out a range ofmeasures throughout the entire lifecycle of mercury to meet its objective, which include measures
to control the supply and trade of mercury, and to control mercury-added products andmanufacturing processes in which mercury or mercury compounds are used, as well as artisanaland small-scale gold mining. The text also includes the articles on emissions and releases of
mercury, on environmentally sound interim storage, on mercury waste, and contaminated sites.
Articles 3 – 12 relate to the operational provisions describing Parties’ obligations to reduce
emissions and releases, with controls along their life cycle. Articles 13 – 21 facilitate theimplementation of these measures including provisions related to support to the Parties,
information and awareness raising and reporting. Articles 22 – 35 cover the overall management of
the Convention. It is also worth noting that the Convention promotes consideration of the needs ofvulnerable populations in health aspects; in public information, awareness and education; inresearch, development and monitoring; and in effectiveness evaluation; are key priorities to be taken
forward. Annexes A and B list the mercury-added products and manufacturing processes to be37

controlled by the Convention. Annex C sets the items to be included in the national action plans forartisanal and small-scale gold mining (ASGM). Annex D lists the point source categories foremission control.

Table 4 Article-by-article outlines of the Minamata Convention
ArticlePreamble
Article 1 Objective
Article 2 Definitions
Article 3 Supply and trade
Article 4 Mercury-added
products
Article 5 Manufacturing
processes
Article 6 Exemptions
Article 7 ASGM
Article 8 Emissions
Article 9 Releases
Article 10 Interim storage
Article 11 Mercury wastes
Article 12 Contaminatedsites
Articles 13 – 14 Finance,technical assistance
Article 15 Compliance
Article 16 Health

Articles 17 – 18
Information, awareness,
education
Article 19 Research,monitoring

38

Outlines
Recognition of mercury risks, substantial lessons of Minamata Disease
Protection of the human health and the environment from anthropogenic
emissions and releases of mercury and mercury compounds.
Definition of terms in the Convention.
Control of primary mercury mining by setting the phase out period.
Prohibition of international trade of mercury except for the use allowed under
the Convention.
Control (including phase out and phase down) of production, import andexport of the mercury-added products in Annex A.
Control (including phase out) of mercury uses in the processes specified in
Annex B.
Registration of exemption from the phase out dates specified in Annexes A
and B.
Reduction (or elimination wherever feasible) of mercury use in ASGM for thecountries having more than insignificant ASGM activities. Development andimplementation of national action plans in accordance with Annex C.
Control of emission into air from the source categories listed in Annex D
based on the best available techniques and best environmental practices.
Preparation of inventory.
Identification of relevant source categories that are not addressed in otherprovision of the Convention. Control of releases to land or water. Preparationof inventory.
Environmentally sound interim storage of mercury other than waste mercury.
Management of mercury wastes in an environmentally sound manner, taking
into account the guidelines developed by the Basel Convention.
Identification and assessment of sites contaminated by mercury or mercury
compounds.
Financial resources and mechanisms, capacity-building, technical assistanceand technology transfer.
Establishment of a Committee as a subsidiary body of the COP, to promote
implementation and review of compliance.
Development and implementation of the health strategies and programmes
to protect population at risk. Development of science-based educational andpreventive programmes on occupational exposures. Appropriate health-careservices for affected populations. Strengthening capacity for diagnosis,
treatment and monitoring of health risks.
Exchange of scientific, technical, economic and legal information among theParties. Promotion and facilitation of the provision of information to the
public.
Cooperation for research and development on inventories, modelling andmonitoring, impacts on human health and the environment, fate andtransport, commerce and trade, mercury-free alternatives, etc.

Article
Article 20 Implementation
plans
Article 21 Reporting
Article 22 Effectivenessevaluation
Articles 23 – 28 COP,
Secretariat, etc.
Articles 29 – 35
Ratification, etc.
Annex A Mercury-added
products

Annex B Manufacturing
processes
Annex C ASGM national
action plans
Annex D Point sources ofemissions

Outlines
Development and execution of implementation plans taking into account thedomestic circumstances.
Periodical reporting to the COP on measures taken by the Parties.
Evaluation of the effectiveness of the Convention on the basis of available
scientific, environmental, technical, financial and economic information.
The COP, secretariat, settlement of disputes, amendments, voting.
Signature, ratification, entry into force, reservation, withdrawal, depositary,
and authentic texts.
Introductory text: General exceptions.
Products essential for civil protection and military uses
Products for research, calibration of instrumentation, for use as reference
standard
Where no feasible mercury-free alternative for replacement is available
Products used in traditional or religious practices
Vaccines containing thiomersal as preservatives
Part I: Products to be phased out
Batteries; switches and relays; lamps; cosmetics; pesticides, biocides andtopical antiseptics; non-electronic measuring devices
Part II: Dental amalgams.
Part I: Chlor-alkali production, acetaldehyde production.
Part II: Vinyl chloride monomer, sodium or potassium methylate or ethylate,
polyurethane.
Content of national action plan.

Coal-fired power plants; coal-fired industrial boilers; smelting and roastingprocesses used in the production of non-ferrous metals; waste incineration
facilities; cement clinker production facilities.
Annex E Arbitration
Arbitration and conciliation procedures.
Source: Minamata Convention (2013). Text of the Minamata Convention on Mercury for adoption by the
Conference of Plenipotentiaries.

394.2 Standards and guideline values
The monitoring results are compared with some other values for judging if the analysed values areabove or below such values. For compliance monitoring, the standards and guideline values set by
the authorities are used for such comparison. For research monitoring, similar monitoring results atthe control sites are often used. The comparison values should be carefully chosen to avoid
misleading the issue. For example, the guideline values for methylmercury toxicity should not be
used for assessing elemental mercury exposures. The interpretation of the results should also bealigned with the conditions used by the particular guidelines. The tables below are not exhaustive
lists but indicate a few examples of values which are frequently referred to. For the actual monitoring
activity, the local standards and guidelines should always be checked.

Table 5 Air (mercury standards and guideline values)
IssuedWHOEurope1WHO2TargetIndoor air

Parameter
Total mercury

Indoor air

Total mercury

ILO3

Workplace

Aryl mercury

MOEJ4

Ambient air

Elemental and inorganic
mercury
Organometallic alkyl
mercury
Total gaseous mercury

MOHLWJ5

Workingenvironment

Inorganic mercury

Type
Guideline
value
Guideline
value

Value
1 µg/m3

Guidance note

0.1 mg/m3

0.2 µg/m3

0.025
mg/m3
0.01 mg/m3
Guideline
value
Administrativelevel

40 ng/m3
0.025
mg/m3
0.01 mg/m3

Annual mean
Estimated
tolerable
concentration for
long-term
exposure
8-hour timeweighted average

Annual mean

Alkyl mercury (methyl
and ethyl only)
Source: 1 World Health Organization WHO (2000). 2 WHO (2021). 3 Niu et al. (eds.) (2022)., 4 Japan, InterMinisterial Coordination Council on the Minamata Convention on Mercury (2017). 5 Japan, Ministry of Labour(1988).

40

Table 6 Water (mercury standards and guideline values)
IssuedWHO1
USEPA

TargetDrinking
water
Freshwater

Parameter
Total
mercury
Inorganic
mercuryType
Guideline valueValue
1 µg/L

Criterion maximum
1.4 µg/L
National
concentration
Recommended
Aquatic Life
Criterion continuous
0.77 µg/L
Criteria2
concentration
Saltwater
Criterion maximum
1.8 µg/L
concentration
Criterion continuous
0.94 µg/L
concentration
Drinking
Maximum contaminant
0.002 mg/L
National
waterlevel goalPrimary
Drinking Water
Maximum contaminant
0.002 mg/L
Regulation3
level
4
EU
InlandMercury
Environmental quality
0.07 µg/L
Maximum
surface water and its
standard(dissolved)
allowable
concentration
Other surface compounds Environmental quality
0.07 µg/L
waterstandard(dissolved)
Biota
Environmental quality
20 µg/kg (ww)standard
MOEJ5
Public water
Total
Environmental quality
0.0005 mg/L
(river, lake,mercury
standard
sea)
Alkyl
Environmental quality
Not detectablemercury
standard(0.0005 mg/L)
Groundwater
Total
Environmental quality
0.0005 mg/L
mercury
standard
Alkyl
Environmental quality
Not detectablemercury
standard(0.0005 mg/L)
Wastewater
Total
Wastewater quality
0.005 mg/L
mercury
standard
MOHLWJ6 Tap water
Total
Drinking water quality
0.0005 mg/L
mercury
standard
Source: 1 WHO (2021). 2 United States of America, Environmental Protection Agency USEPA (2022a). 3 USEPA(2009). 4 European Union EU (2013). 5 Japan, Inter-Ministerial Coordination Council on the Minamata
Convention on Mercury (2017). 6 Japan, Ministry of Health, Labour and Welfare MOHLWJ (2020)

Table 7 Soil (mercury standards and guideline values)
IssuedMOEJ1TargetSoil (leaching
test)

Parameter
Type
Value
Total mercury
Environmental quality
0.0005 mg/L
standard
Alkyl mercury
Not detectable (0.0005 mg/L)
Total mercury
Soil contamination
0.0005 mg/L (0.0005 mg/L)
countermeasure
Alkyl mercury
Not detectable
standard
Soil (content)
Total mercury
15 mg/kg
Source: 1 Japan, Inter-Ministerial Coordination Council on the Minamata Convention on Mercury (2017).

41

Table 8 Sediment (mercury standards and guideline values)
IssuedMOEJ1TargetSea sedimentParameter
Total mercury

TypeInterimStandards
for
Sediment
RemovalValue
Removal standard (mg/kg (dw) or ppm) *＝ 0.18 x [tidal difference (m) ]/ [Hg elution rate from sample sediment]/ [safety ratio]
25 mg/kg (dw)River or lake
Total mercury
sediment
Source: 1 Inter-Ministerial Coordination Council on the Minamata Convention on Mercury, Japan (2017).

Table 9 Fish and other food items (mercury standards and guideline values)
IssuedUSEPA1USFDA2EU3

MOHLWJ4

TargetFish
Fish, shellfish, crustaceans, otheraquatic animals (fresh, frozen orprocessed)
Wheat (pink kernels only)

Fishery products and muscle meat offish excluding species listed below*Except for the followings:- brown meat of crab
- head and thorax meat of lobster
and similar large crustacean
Muscle meat of fish (species defined)

Parametermethylmercury
methylmercury
in edible portion
pink kernels (anaverage of 10 ormore pinkkernels/500 g)
Total mercury

Total mercury

Type
Human healthcriteria
Action levelValue
0.3 mg/kg
1 mg/kg
1 mg/kg

Maximumlevel in food
stuff

0.1 mg/kg(ww)

1.0 mg/kg(ww)
0.4 mg/kg
0.3 mg/kg

Fish and shellfish
Total mercury
Provisional*Except for the followings:
standard
Methylmercury(reference- Tuna (tuna, swordfish, bonito)
value)- River water fish
- Deep sea fish (sting fish, alfonsin,
sablefish, red queen crab, ivory
shell, sharks)
Source: 1 USEPA (2001a). 2 United States of America, Food and Drug Administration FDA (2000). 3 EU (2006).
4 MOHW (1973).

42

Table 10 Waste (mercury standards and guideline values)
Issued
USEPA

MOEJ3

TargetSewagesludge1

Hazardous
waste2
Slag, sootand dust,
sludgeWaste acid,waste alkali
Burn residue,slag, sootand dust,
sludgeWaste acid,waste alkali

Type
Cumulative loading forsludge applied on
agricultural, forest andpublicly accessible lands
Annual loading rate forsludge sold or distributed
for application to a lawn orhome garden
Sludge sold or distributedfor other types of landdisposalHazardous waste
regulation
Specially controlledindustrial waste regulation

Value
17 mg/kg(dw)
17kg/hectare
17 mg/kg(dw)
85kg/hectare
57 mg/kg(dw)
0.2 mg/L

Leaching test

0.005 mg/L

If the waste contains 1000
mg/kg or more of mercury,mercury in it must be recovered.
If the waste contains 1000
mg/L or more of mercury,mercury in it must be recovered.
If the waste contains 1000
mg/kg or more of mercury,mercury in it must be recovered.

0.05 mg/L
Regulation of mercury
containing dust, etc.

15 mg/kg

15 mg/L

If the waste contains 1000mg/L
or more of mercury, mercury in
it must be recovered.
Source: 1 USEPA (2018). 2 USEPA (2022b). 3 Japan, Inter-Ministerial Coordination Council on the Minamata
Convention on Mercury (2017).

Table 11 Air emissions (mercury standards and guideline values)
IssuedFacilities or equipment

StandardNew
established

USEPA

Coal- and oil-fired
electric utility steam
generating units1

Coal-fired unit

Not low rank virgincoal
3.0e-3lb/GWhLow rank virgin coal
4.0e-2lb/GWhExisting facility
1.2e+0 lb/TBtu or
1.3e–2 lb/GWh(Testing for 30
days)
1.0e+0 lb/Tbtu or
1.1e–2 lb/GWh(Testing for 90
days)
4.0e+0 lb/Tbtu or
4.0e–2 lb/GWh(Testing for 30
days)

43

IssuedFacilities or equipment

StandardNew
established3.0e
lb/GWh2.5e+0 lb/Tbtu or
3.0e–2 lb/GWh(Testing for 30
days)

1.0e-4lb/GWh2.0e–1 lb/Tbtu or
2.0e–3 lb/GWh

4.0e-4lb/GWh

4.0e–2 lb/Tbtu or
4.0e–4 lb/GWh

IGCC unit-3

Liquidoil-fired
unit

Continental (excluding
limited-use liquid oil-fired
subcategory units)
Non-continental (excluding
limited-use liquid oil-fired
subcategory units)
Solid oil-derived fuel-fired unit

-3

2.0e
lb/GWhEastern Bituminous Coal Refuse-fired
unit2-

Portland cement
manufacturingindustry3
Large municipal
waste combustors4

Combust greater than 250 tons per
day of municipal solid waste

Small municipal
waste combustors5

Combust from 35 to 250 tons per dayof municipal solid waste

Commercial andindustrial solid waste
incineration units6
Sewage sludge
Multiple hearth sewage sludge
incineration units7
incineration
Fluidized bed sewage sludge
incineration

Hospital/ medical/
infectious waste
incinerators8

44

Large (>500 lb/hr of waste)
Medium (>200 to ≤500 lb/hr ofwaste)

Existing facility

21
lb/million
metric tons
clinker
50 μg/m3(dscm@
7 % O2)0.080
mg/m3(dscm @
7 % O2)0.15 mg/m3(dscm @
7 % O2)0.0010
mg/m3(dscm@
7 % O2)-2.0e–1 lb/Tbtu or
2.0e–3 lb/GWh(Testing for 30
days)
1.2e+0 lb/Tbtu or
1.3e–2 lb/GWh(Testing for 30
days)
1.0e+0 lb/Tbtu or
1.1e–2 lb/GWh(Testing for 90days)
55 lb/million metrictons clinker
50 μg/m3 (dscm@
7 % O2)0.016 mg/m3(dscm@ 7 % O2)
0.28 mg/m3(dscm@ 7 % O2)
0.037 mg/m3(dscm@ 7 % O2)
0.018 mg/m3(dscm@ 7 % O2)
0.025 mg/m3(dscm@ 7 % O2)

IssuedFacilities or equipment

StandardNew
established

Small (≤200 lb/hr of waste)

Gold ore processing
and production
facilities

Small rural (small facility >50 miles
from boundary of nearest SMSA,
burning <2,000 lb/week of waste)
Ore pre-treatment processes

Carbon processes with mercury
retorts
Carbon processes without mercury
retorts
Non-carbon concentrate processes
MOEJ9 Coal fired power plant Coal-fired boiler
Industrial coal
Large coal mixed combustion boiler
combustion boiler
Small coal mixed combustion boiler
Process of refining
Primary
Copper or industrial gold
and roasting used for facility
Lead or zinc
manufacturing
Secondary Copper, lead or zinc
nonferrous metals
facility
Industrial gold(copper, lead, zincand industrial gold)
Equipment for
Waste incinerator（Municipal waste /incineration of waste
industrial waste / sewage sludge

Existing facility-

0.014 mg/m3(dscm@ 7 % O2)-

0.0051 mg/m3(dscm@ 7 % O2)

84lb/million
tons of ore
0.8 lb/ton ofconcentrate
0.14 lb/tonofconcentrate
0.1 lb/ton ofconcentrate

127 lb/million tonsof ore2.2 lb/ton ofconcentrate
0.17 lb/ton ofconcentrate
0.2 lb/ton ofconcentrate

8 μg/Nm3

10 μg/Nm3

10 μg/Nm3

15 μg/Nm3

15 μg/Nm3

30 μg/Nm3

350 μg/Nm3

30 μg/Nm

100 μg/Nm3 400 μg/Nm3
30 μg/Nm3

50 μg/Nm3

30 μg/Nm3

50 μg/Nm3

50 μg/Nm3

100 μg/Nm3

incinerator）
Incinerators such as mercurycontaining sludge etc.

Equipment forFiring furnace provided for
manufacturing
manufacturing cement
50 μg/Nm3
803 μg/Nm3
cement clinker
Source: 1 USEPA (2016a). 1 lb = 454 g, 1 lb/GWh = 454 g/GWh, 1 lb/Tbtu = 1.55 g/GWh. 2 New category
established by USEPA (2020). 3 USEPA (2012). 4 USEPA (2006) 5 USEPA (2000). 6 USEPA (2016b). 7 USEPA(2011). 8 USEPA (2013). 9 Japan, Inter-Ministerial Coordination Council on the Minamata Convention on
Mercury (2017). Existing facilities means the facilities built before April 2018.

3

For raw material limestone those having a mercury content of 0.05 mg or more in 1 kg, standard is 140 μg
/Nm3

45

Table 12 Hair and blood (reference value corresponding to mercury tolerable intake)IssuedWHO1

Value
1.6 μg/kg (bw)-week- Based on BMDL/NOEL derived
from 14 mg/kg of maternal hair,
which is equivalent to a maternal
blood methylmercury
concentration of 0.056 mg/L.
- Daily intake of methylmercury of
1.5 μg/kg (bw) is divided by atotal uncertainty factor of 6.4 togive a value of 1.6 μg/kg (bw) in
weekly basis.
- Hair mercury concentration
divided by the uncertain factor of
6.4 is 2.2 mg/kg.
Adult
MethylIntakes of up to about two times
mercuryhigher than the PTWI of 1.6 μg/kg(bw)-week would not pose any risk ofneurotoxicity in adults.
- Hair mercury concentration
about two times higher than thelevel of the PTWI is 4.4 mg/kg.
Infant and children MethylNo clear line drawn
aged up to about
mercury- Clearly not more sensitive than
17 years
the embryo or fetus but might bemore sensitive than adults.
USEPA2 Offspring at 7
MethylOral reference dose
14.1 μg/kg (bw)-day
years of age
mercury(RfD) for- Derived from integrated analysis
developmentalof benchmark dose levels
neuropsychologicalranging between 0.046 mg/L andimpairment
0.079 mg/L of maternal cord
blood corresponding to 11 mg/kg
and 20 mg/kg of maternal hair.
- Uncertainty factor 10 applied tocorresponding values ofmaternal daily intakes of 0.8571.472 µg/kg (bw)-day.
- Hair mercury concentration
divided by uncertain factor of 10
is between 1.1 mg/kg and 2.0
mg/kg.
Source: 1 Joint FAO/WHO Expert Committee on Food Additives JECFA (2007). 2 USEPA (2001b).

46

TargetPrenatal exposure
to methylmercury
on child
neurodevelopment

Parameter
Methylmercury

Type
Provisional tolerable
weekly intake(PTWI)

4.3 Process flows
0.5 g max (Hair: 10
mg)

SamplePure water 1 mL
HNO3 + HClO4 (1+1) 2 mL
H2SO4 5 mL

Digestion

Heat (200-230ºC, 30 min)Cooling to room temp.
Top up to 50 mL

10% SnCl2 1 mL
Reduction

CVAAS Measurement

Japan, Ministry of the Environment (2004). Mercury analysis manual. March 2004.

Figure 1 Flowchart of total mercury analysis by acid digestion – aeration CVAAS

47

Water Sample

2L(Filtered)

20N H2SO4 10 mL
0.5 % KMnO4 5 mL

Oxidization(organic phase)

Precisely take 7 mL

Concentration
Drying up

5 min

HNO3 + HClO4 (1+1)
H2SO4

10N NaOH 20 mL
10 % NH2OH-HCl 5 mL
Still standing 20 min
10 % EDTA 5 mL
0.01 % dithizone-toluene 10 mL

Digestion

Cooling to room temp.
Top up to 50 mL

Extraction
Still standing 1 hour
Centrifuge

Heat (200-230ºC), 30 min

10 % SnCl2 1 mL
Reduction(waste aqueous phase)
CVAAS Measurement

Japan, Ministry of the Environment (2004). Mercury analysis manual. March 2004.

Figure 2 Flowchart of total mercury analysis in water by dithizone extraction aeration CVAAS

48

Biological
Sample0.2-0.5 g(aqueous phase)Toluene 7 mL

1N KOH-EtOH 10 mL
Digestion

Heat (100ºC, 60 min)Extraction
Centrifuge

Cooling to room temp.
1N HCl 10 mL
Hexane 5 mL

(waste organic phase)(aqueous phase)

Extraction
Centrifuge

1N HCl 3-5 drops(waste organic phase)N2 bubbling (50 mL/min, 3 min)(aqueous phase)

Walpole’s buffer 2 mL

20 % EDTA 2 mL
0.01 % dithizone-toluene 5 mL
Extraction

0.01 % dithizone-toluene 0.5 mL
Extraction
Centrifuge

Centrifuge(waste aqueous phase)(waste aqueous phase)(organic phase)(organic phase)

1N NaOH 3 mL
Na2SO4 0.5 g
1N NaOH 3 mL

Extraction
Centrifuge

Extraction
Centrifuge(waste aqueous phase)(waste aqueous phase)(organic phase)
1N HCl 2 drops(organic phase)
Alkaline sodium sulphide 2 mL
Extraction

Extraction
Centrifuge(waste aqueous phase)

Centrifuge(waste organic phase)(organic phase)
GC/ECDmeasurement

Japan, Ministry of the Environment (2004). Mercury analysis manual. March 2004.

Figure 3 Flowchart of methylmercury analysis in biological sample by dithizone extraction GC/ECD

49

Hair Sample

10 mg
EtOH 1-2 drops
2N HCl 3 mL

Extraction

Heat (100ºC, 5 min)Cooling to room temp.
Centrifuge
Precisely take 1 mL solution
Toluene 2 mL

Extraction
Centrifuge(waste aqueous phase)(organic phase)
GC/ECDmeasurement

Japan, Ministry of the Environment (2004). Mercury analysis manual. March 2004.

Figure 4 Flowchart of methylmercury analysis in hair sample by HCl extraction GC/ECD

50

4.4 List of certified reference materials
Table 13 Certified reference materials of mercury
Category
Hair
Food
Biota
Sediment
Urine
Biota
Sediment
Soil
Plant
Food
Waste
Biota
Sediment
Hair
Biota
Soil
Hair
Urine
Soil
Soil
Sediment
Biota

Material
Human hair powder
Lichen powder, Cabbage powder
Freeze-dried tuna meat, Freeze-dried scallop,
Cotton cellulose powder, Freeze-dried clam
Lake sediment, Coastal sediment, Marine
sediment
Frozen human urine
Oyster tissue, Lake Superior fish tissue, Lake
Michigan fish tissue, Bovine liver
Estuary sediment, New York/New Jersey
Waterway Sediment, Inorganics in marine
sediment, Sediment for solid sampling
Soil containing lead from paint, New Jersey soil,
San Joaquin soil, Montana soil
Apple leaves, Peach leaves, Spinach Leaves,
Tomato leaves, Pine needles
Typical diet, Wheat flour, Rice flour, Green tea
leavesHard rock mine waste, Domestic sludge, Industrial
sludgeDogfish liver, Fish protein, River prawn, Cuttlefish,
Lobster Hepatopancrea
Marine sediment
Human hair powder
Freeze-dried fish meat powder
Air-dried sieved soil
Human hair powder
Human urine (high concentration, lowconcentration)
Forest soil, Hg added forest soil
Heavy meal added forest soil
Marine sediment, Lake sedimentFreeze-dried cod meat, Freeze-dried swordfish
tissue

T-Hg
X
X
X

MeHg
X

Manufacturer
International Atomic
Energy Agency

X

X
X
X

X

National Institute ofStandards andTechnology

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

X

National ResearchCouncil Canada

X

National Institute forEnvironmental
StudiesNational Institute for
Minamata Disease

X

X

Japan Society for
Analytical Chemistry
National Metrology
Institute of Japan

51

4.5 Physical and chemical properties,
usage, and environmental behaviours of
mercury
Physical and chemical properties of mercury
Mercury is a chemical element that exists in various forms with unique physical properties. With an
atomic number of 80, which is next to gold, mercury is the only metal element that exists in liquid
form at normal temperatures. In addition, mercury has a low boiling point among metallic elements,
and it is volatile with high a vapour pressure. The abundance of mercury in Earth’s crust is similar tothat of silver, but mercury has a much lower market price than precious metals.

Table 14 Physical properties of elemental mercury
Atomic number: 80
Atomic weight: 200.59
Melting point: -38.8 °C
Boiling point: 356 °C
Specific gravity: 13.6 at 0 °C
Thermal conductivity: 8.3 W/m°C
Saturated vapor concentration: 13.2 mg/m3 at 20 °C
Abundance in Earth’s crust: 0.05 – 0.08 ppm
Emission spectrum at ultra-violet band: 254 nm (UV-C)
Forming amalgam with many metallic elements

Source: Japan, National Institute for Minamata Disease (2013). Mercury and health V4.1.

Figure 5 Molecular similarity of methylmercury-cysteine complex and methionine

52

Methylmercury is a mercury compound of great concern due to its high toxicity. Methylmercury
binds cysteine, a kind of amino acid, to form a complex with a molecular structure similar tomethionine, an essential amino acid (Figure 5). Due to this similarity, the complex is actively
absorbed via an amino acid transporter. Then, it is incorporated into body tissues made of protein
including the brain and fetus.
Most mercury and mercury compounds have certain toxicities, but their biological behaviours andtoxicity levels differ. Main exposure pathways, symptom and treatment for three (3) types of mercury
and mercury compounds are shown in Table 15. The absorption rates of inhaled elemental mercury
and ingested methylmercury are very high, while the absorption rate of inorganic mercury is rather
low. Ingested elemental mercury is usually directly excreted without absorption. Absorbed mercury
is gradually oxidized and excreted in urine as inorganic mercury. Elemental mercury passes throughthe blood-brain barrier and causes mercury poisoning of the central nervous system. Accidental
high-level exposure to mercury vapour in the workplace can be fatal, but acute symptoms are usually
reversible. The symptoms of chronic low-level exposure to elemental mercury were known as madhatter’s disease. Methylmercury is transported actively to form body tissues made of protein. The
adverse effects depend on the body parts into which methylmercury is incorporated. Ingested
inorganic mercury causes inflammation of the digestive tract and kidney damages if the amount isvery high. Acute mercury exposure is usually treated by stimulating the excretion. For chronic
exposure, stopping exposure is the most important measure.

Table 15 Exposure pathway, symptom and treatment
Elemental Mercury
Exposure
pathway(absorption
rate)

-

Behaviourand fate--

Inorganic Mercury

Inhalation (75-85 %)Ingestion (0.01 % or less).

-

Unoxidized form passes
through blood-brain barrier(by diffusion)
Gradually oxidized todivalent inorganic mercury--

Methylmercury

Ingestion (5-10 % or
less)
Dermal (not expected
to be high).

-

Ingestion (90 % or more)

Excreted in urine-

Passes through bloodbrain and placenta
barrier (by amino acidtransportation)
Gradually oxidized todivalent inorganic
mercury-53

Elemental Mercury
Symptom-

Treatment-

Inorganic Mercury

Respiratory distressCentral nervous systemeffects (tremor, personalitychange, tooth pain,
excessive salivation)
Referred to as ‘madhatter’s disease’--

Methylmercury

Corrosion in digestive
tract (vomiting, chest
pain, abdominal pain,
and bloody diarrhoea)
Kidney damage
Renal insufficiency--

Central nervous systemeffects (sensory nerve
dysfunction, ataxia, andconstriction of visual
field)
Fetal exposure (nonspecific cerebral palsylike features)-

Gastric lavage,- No effective treatment
excretion withchelating agent
Source: Japan Public Health Association (2001). Preventive Measures against Environmental Mercury
Pollution and Its Health Effects.
Stimulation of mercury
excretion

Mercury products and uses
Mercury is one of a few elements known since ancient times. It has been used for various purposes
for many thousands of years as shown in Figure 6. Red pigments and the preservation of corpses
are among the oldest applications. The demand of mercury has increased as new uses have been
invented over time. The supply side, that is mercury mining, has also been well developed to support
the demand for mercury. Today, some mercury-added products and processes have been replaced
by non-mercury alternatives, but many are still widely used globally. The Minamata Convention
controls the products and processes stipulated in the Annexes, but even after phase out, mercury
waste will continue to be generated for a long time. Thus, proper management of mercury waste isvery important.
New Almaden
Almadén
Idrija(USA)(Spain)(Slovenia)
Red pigments
Corpse preservation
Gold plating
Pharmaceuticals
AlchemyCosmetics
Gold & silver extraction
Vacuum pumps & gauges
Temperature & pressure measurement
Dental restoration
Explosives
Electrolysis
Discharge tubes
Pesticides & antiseptic
Batteries
Catalysts
Switches & relays

Mercury mines:

3000

BC/AD

1000

1500

1800

Figure 6 Historical mercury supply and use

54

1900

Itomuka(Japan)Control underMinamata
Convention

Annex A I
Annex A I
Annex C
Annex A I
Annex A II
Annex B
Annex A I
Annex A I
Annex A I
Annex B
Annex A I
1950

2000 YearAs shown in Figure 7, global mercury use is estimated to be approximately 4700 tons per year asof 2015. Artisanal and small-scale gold mining is the largest mercury consumer, and Asia, Africa,
Latin America and the Caribbean are the regions consuming a large amount of mercury.

Electrical andelectronic devices
3%
Lamps
Other
3%
7%
Measuring andcontrol devices
7%
Dental application
6%
Batteries
5%

Total 4715 tons
(2015)

Chlor-alkali
production
6%

EU
5%

North
America3%

CIS & non-EU
Europe4%
ASGM
37%

Oceania
0.5%

Latin
America &Caribbeans
19%

VCM
production
26%

Middleeast
2%

Total 4715 tons
(2015)

Asia
57%

Africa10%

Source: United Nations Environment Programme (2017). Global mercury supply, trade and demand.

Figure 7 Global mercury uses by sector and by region

Use of elemental mercury
Elemental mercury is used for measuring purposes. As a high-density liquid, it is suitable formeasuring pressure. Devices such as manometers, barometers, and sphygmomanometers, enableprecise pressure measurement without using electricity. For official purposes, “mmHg” or “inHg”
can still be used as non-SI units of measurement. Mercury is also useful for measuring temperature
because it exists in liquid form in a wide temperature range (-38.8 °C to 356 °C). As a metallic
element, mercury has a high thermal conductivity, which provides a quick response. Some mercuryadded measuring devices are subject to phase out under the Minamata Convention.
A discharge tube is an electronic device that contains gas or vapour at low pressure, and throughwhich conduction takes place when a high voltage is applied. The mercury arc rectifier was animportant device for converting high voltage alternating current (AC) to direct current (DC). As
modern electricity supply networks were developed with AC, rectification was required if the industry
required DC. Today, this function is mostly performed by power semiconductors. Several gaseous55

elements, including mercury vapour, emit various wavelengths of light. Mercury discharges ultraviolet ray (UV-C) which is invisible to humans. As UV-C damages DNA, mercury vapour lamps areused for microbial disinfection. Fluorescent lamps convert UV-C to visible light for lighting
applications. The light emitted from discharge tubes are also used for various lighting applications,such as indoor and outdoor lighting, signage, and the headlamps of vehicles.
As mercury is electrically conductive, it is used for various electric controls. The mercury switch has
several advantages for closing and opening electrical circuits. As the contact surface is concealed,
no oxidation occurs, and the surface remains clean with a low resistance due to the wetting natureof mercury. Application includes tilt switches to activate lights on the boot lids of vehicles, rollover
warning device for vending machines, anti-lock braking systems that detect acceleration force, highspeed switch as mercury relay does not cause chattering, and mercury slip rings that transmit
signals or power to devices over 360° of rotation.
Mercury is added to batteries for safety purposes to prevent hydrogen gas generation. Abnormal
reactions at the zinc anode causes cell rupture or leakage, but mercury inhibits such abnormal
reactions. Although most dry cells have stopped using mercury, a few types of button cells still use
mercury for this purpose. Lithium coin cells do not use water as the electrolyte, so no mercury isadded.
Elemental mercury is also used for many other purposes. Some are being phased out as nonmercury alternatives are becoming increasingly available. It is important to be aware that not alluses of mercury are subject to the Minamata Convention, so legitimate uses of mercury will remain.
The applications of elemental mercury are summarized in Table 16

Table 16 Applications of elemental mercury
Type
Measuring
devices

Theory / Principle-

High density
liquidApplication-

56

Manometer (pressure insystem, facility, etc.)
Barometer (atmosphericpressure)
Sphygmomanometer (bloodpressure)

Remarks--

No electric supply
required.
No equivalent alternative
for high temperaturedevices.
Extensively used formeasuring bloodpressure.

Type
Ditto

Theory / Principle--

Discharge
tubes-

Application

Liquid in wide
temperature
range
High thermal
conductivity-

Electric valve
effect-Remarks

Thermometer (temperature)
Hygrometer (wet bulb, relative
humidity)-

Mercury arc rectifier (rectifying
high voltage AC to DC)

-

-

Ditto

-

Emitting UV-C
(254nm)-Switches
and relays-

Electricallyconductive liquid
Wetting effect on
contact surface-

Neon lamp (signage, display)
Fluorescent lamp (lighting)High-pressure discharge lamp
(projection, lighting, suntanning, headlamp of vehicles)
Low pressure mercury vapour
lamp (disinfection)-

Tilt switch/alarm (activating
lights for boot lids of vehicles)
Acceleration censor (anti-lockbraking systems)
Mercury-wetted relay(power/signal transmission for
360° rotating devices)

-

-

-

No electric supply
required.
Quick response.
No equivalent alternative
for high temperaturedevice.
Large power supply
capacity for industries
requiring DC.
Largely replaced bypower semiconductors.
No filament in bulb, longlife.
UV-C emitting efficiency
is higher than LED.

Low resistance and nochattering at contact
surface.
Allows high frequency
switching.

Batteries-

Hydrogenoverpotential-

Button cell (preventinghydrogen gas generation atzinc anode)-

Lithium coin cell does
not use water, thus nomercury is added.

Vacuumpumps-

High density
liquidAir induction-

Mercury column pump (1Pa)
Mercury rotary pump (10-2Pa)
Mercury diffusion pump (103Pa)-

Replaced with oil-based
fluid.

Balancers-

High density
liquid-Wheel balancer
Trim and heel controller(submarine)-

Non-mercury (solid)balancers are available.

Laboratory
instruments-

High surface
tension-Porosimeter-

Used to analyse porosityof material surfaces.

Fluidbearings-

High density
liquid-Lighthouse rotation unit-

Floating Fresnel lens.

Electric
conductors-

Electricallyconductive liquid-

Slip ring (360° rotation)-

Brushless contact.

Mirrors-

Liquid with highreflectance-

Liquid zenith telescope-

Rotating mirror to form
paraboloid mirror.

Propellants-

Easy ionization-

Ion thruster (satellites)-

Replaced by xenon.

57

Use of amalgam
Mercury can form various alloys with other metals, which are called amalgam. Amalgam has been
an important material for many industries as final products or in production processes. Dental
amalgam is a mixture of silver and tin powder, which is gradually hardened to fill dental cavities. Tin
amalgam was used for the reflective surfaces of mirrors.
Gold and silver extraction and refining have been practised for many thousands of years. The oldest
method called cupellation used lead and was invented in BC era. There was a risk for lead poisoning
with this method. The amalgamation method was then invented in the 16th century when silvermining in Latin America was at its peak. Due to the melting and boiling points of mercury being
lower than those of lead, the consumption of heat sources, i.e., firewood, was reduced, which
preserved forests in the region. The amalgamation method for ASGM accounts for the largest usageof mercury today and disproportionally affects marginalised and less privileged groups. The cyanide
method was invented in the late 19th century during the Gold Rush era. This method is currently
predominantly used for large-scale gold mining operations, but its application to ASGM is being
explored.
NaCl, which is the chemical form of edible salt, can generate chlorine gas and caustic soda byelectrolysis. Caustic soda is used for manufacturing products such as soap and glass, and chlorine
gas is used for producing disinfection and bleaching agents as well as PVC. Mercury is used as theelectrode for the mercury-cell process, which was invented in the early 20th century and still is usedin some countries. Chlorine ions are oxidized at the anode and become chlorine gas. On the cathodeside, where mercury is used, sodium ions are reduced to metallic sodium, which forms an amalgam
with mercury. The sodium amalgam is then sent to an amalgam decomposer, where caustic soda
is formed. The key to this electrolysis process is blocking sodium backflow to the anode side. The
diaphragm process physically blocks this backflow with the fibrinous structure of asbestos. Thissystem is still used but the risk of asbestos is a concern. The membrane process has a similar
configuration to the diaphragm process, but an ion exchange membrane allows the selective
permeation of sodium ions to the cathode side, which is more energy efficient and avoid toxic
substances.
Special applications of amalgam include low-temperature thermometers with thallium amalgam,
which is melting temperature of approximately minus 60 °C. However, mercury is problematic in theoil and gas sector. Mercury erodes aluminium equipment, such as heat exchangers, and inactivates
palladium-based catalysts. The applications of amalgam are summarized in Table 17.

58

Table 17 Applications of amalgam
Type
Dental filling

Theory / Principle- Graduallyhardening after
mixing-Application
Dental cavity restoration(filling silver tin amalgam into
dental cavities)-

Gold/ silver
industry--

Absorption of
metallicelements
Low boiling point-

Gold/silver extraction(predominantly used for
ASGM)Gold plating (gold amalgam issmeared on metallic surface
and then heated)-

Gradually
hardening after
mixingAbsorption of
metallicelements-

Mirror (tin amalgam forms thereflective surfaces)--

Chlor-alkali production(separating sodium from brine
after electrolysis)

-

-

-

Mirrorsurfaces-

Electrolysis-

Measuring
devices-

Low temperature
alloy

-

Low temperature thermometer-

Oil and gas(problematic)-

Creating
unwanted
amalgam-

Aluminium equipment (eroding
surface of equipment)
Palladium catalyst(inactivating the catalytic
function)--

Remarks
No electric supply
required.
Mercury waste isreleased into drainage.
Mercury is gradually
vapourised in the mouth.
Workers and somecommunity members
are exposed to mercury
vapour.
Cyanide method is analternative for extraction
but requires higher
management skill.
Replaced by silver mirror
reaction.
Ion exchange membraneprocess is an alternativewith a higher energy
efficiency.
Melting temperature ofthallium amalgam is 60oC.
Mercury removal
process should beinstalled in the system.

Use of mercury compounds
Mercury sulphide is naturally found as cinnabar, which exists as blood red crystals or dark red stones.
Red is one of the oldest colours that humans have intentionally used since the pre-historic era. Three
major red pigments have been used. Iron oxide provides brownish red, and is easily available fromred clay soil. By contrast, mercury sulphide needs laborious refinement from ore, so it was an
expensive pigment. It can also be synthesized from mercury and sulphur. Due to its preciousness,
mercury sulphide was used for more important occasions, such as ceremonial and religious
purposes. Lead oxide is also a synthesized pigment with a bright orange colour.
Cosmetics also use colour, which are predominantly consumed by women. Red, white, and black are
the three base colours for cosmetics. Red pigments, such as cinnabar, were used for bodypainting59

in some indigenous societies. More broadly, white face powder has been used for makeup. Calomel,
mercury (I) chloride, is a white powder used for such purposes. Other chemicals, including lead white
and talc, have also been used. Lead poisoning by face powder was problematic in the past few
centuries. Currently, concerns have been raised about talc, which contains asbestos as an impurity.
Mercury use for skin-whitening cream is another concern, as it is still widely used globally. The
preference to lighter coloured skin is still prevalent in many countries where the skin care industry
keeps feeding illegal products into market.
The ‘biocidal action’ of mercury is used for fungicides and preservatives. Organic mercury
compounds such as phenylmercury have been used for seed dressing, as fungicides for crops suchas rice and wheat. Among inorganic mercury compounds, mercury chloride has been used for woodpreservation, and red mercury oxide has been used for anti-fouling ship paint. In some products thatare directly applied to humans, mercury compounds are still used as preserving agents. For example,
thiomersal preserves vaccines at normal temperatures, which is important when providing vaccines
to remote areas where no cold chain is available.
Mercury has been used in pharmaceuticals since ancient times. Traditional Chinese and Ayurveda
medicines still include mercury products. One of the most significant historical uses of mercury forpharmaceutical purposes is the treatment of syphilis patients. Syphilis emerged in the late 15th
century and rapidly spread over the globe. Many types of mercury compounds were used for medical
treatment from the 16th century, until being replaced by penicillin in the 1940s. Mercurochrome is awater solution of the organic mercury compound merbromin, which was invented in the early 20th
century and has been widely used for treating minor wounds. Its less painful nature and cheap priceallowed various applications in both clinical and household settings. Mercury inhibits the growth of
microorganisms. This characteristic has been used for many preservation and antiseptic purposes.
A catalyst is a substance that facilitate or accelerates a chemical reaction, but its form remains
unchanged. The elements in the zinc group, which includes mercury, have been used as catalysts
for organic synthesis, particularly for the production of vinyl polymers by accelerating addition
reactions from acetylene. The catalysts form intermediate compounds to promote addition
reactions. Minamata disease was caused by the mercury catalyst, mainly mercury (II) sulphate, used
for acetaldehyde production, which was methylated in the factory and then released into theenvironment. To avoid the use of mercury, ethylene can be used for the feedstock instead ofacetylene. Another type of catalyst is the initiator for polymerising polyurethane elastomer, called
latent catalyst, which triggers the process in moulded products or coating. There are many types of
mercury and non-mercury catalyst used as the latent catalyst, among which phenylmercury acetate60

is commonly used for this purpose. Although mercury acts as a catalyst for this process, it remains
in the final product.
Batteries, especially chemical batteries utilize the oxidation and reduction of chemical compounds
to store electricity. The mercury cell is a type of battery that has mercury oxide cathode. Onceelectricity is consumed, mercury oxide is reduced to metallic mercury, which flows out of thecathode. This product is subject to phase out under the Convention. However, mercury use forresearch, calibration, and reference is exempted from the Convention, so standard cells such as theWeston cell are not subject to phase out.
Various mercury compounds are used for many other purposes. One of historical uses is mercury(II) nitrate for hat making. A process called ‘carroting’ was extensively used for the preparation of
felt. Mercury (II) fulminate was also an important mercury compound used extensively during wars
as a material for the detonation caps of explosives. A new use has been examined for mercury (II)sulphide for the final disposal of mercury waste because stabilisation is required in some countries
to dispose of mercury. The applications of mercury compounds are summarized in Table 18

Table 18 Applications of mercury compounds
Type
Mercurysulphide/
cinnabar

Theory / Principle- Low solubility
and stablechemical form.
- Reddish colour--

Mercury (I)chloride /calomelMercury (II)
oxide

-

-

-

Bactericidal &fungicidal actions
White colour
Stable electrodepotential-

Forming liquidmercury once
reducedBiocidal action-

Application
Red pigment (vermillion
refined from cinnabar orsynthesised from mercury
and sulphur).
Bodypainting (ancientindigenous custom)
Waste mercury (stabilisation
for final disposal)
Pharmaceuticals (syphilis)
White face powder
Saturated calomel electrode

-

-

-

-

Battery (cathode for mercury
cell)
Antifouling paint for ship’s
bottom--Remarks
Iron oxide (brownish
red ochre) and leadoxide (bright orangered) have also beenused.

Lead white (leadpoisoning), talc
(contaminated withasbestos).
Silver chloride
reference electrode isan alternative.
Mercury cell has been
replaced with nonmercury alternatives.
Replaced with copperbased ship paint.

61

Type
Mercury (II)sulphate

Mercury (II)nitrateMercury (II)chloride

Theory / Principle- Forming
intermediate withacetylene- Forming liquidmercury once
reduced- Fulling fur-

Bactericidal &fungicidal actions
Water solubility
Reduce silver
halide (photo)
Forming
intermediate withacetylene-

Phenylmercury

-

-

-

Carroting (preparation of felt)--

Fungicide (woodpreservation, seed dressing)Preservative (pulp & paper)Standard solution (mercury
analysis)Push-processing for photo,motion picture and X-ray
films
Catalyst (vinyl chloride
monomer production)
Skin whitening cream(bleaching melamine)
Antiseptic ointment
Fungicide (seed dressing
against rice blight)
Preservative (for latex paint,
pulp & paper)
Latent catalyst (polyurethane
elastomer)
Preservative (vaccine and eye
area cosmetics)--

Ammoniated(II) mercury

Application
Catalyst (acetaldehyde
production)
Weston standard cell
(producing highly stable
voltage for calibration)

Bleaching effectInhibition ofbacterial growth
Bactericidal &fungicidal actions
Initiating
polymerization
reaction-

Extensively used for hat
making in the 19th
century.
Volatile compound,which sublimateseasily.

-Widely used indeveloping countries.

-

Widely used in paddy
fields.

-Vaccine can be stored
at normal temperature
without refrigeration.
Less absorbed fromskin surface (due tohydrophilic nature).

Thiomersal-

Bactericidal
action-Merbromin--

Mercurochrome (topicalantiseptic for minor wound)--

Inhibition ofbacterial growth
Water solubility
Thermochromism-

Thermochromic paint--

Explosiveness

-

-

-

Chemical
reaction spewing
out ash-Detonation cap (blasting
dynamite, bullet cartridge)
Pharaoh’s snake (firework)

Mercury (II)iodideMercury (II)fulminateMercury (II)thiocyanate

Remarks
Acetylene-based
acetaldehyde
production has been
replaced with ethylenebased system.

-

Alter crystal structure
at certain temperature.
Replaced by DDNP.
Generating toxic smokeand residue

Mercury emissions and releases and its risks
As a chemical element, mercury has existed on Earth since its creation. Mercury is released fromnatural sources by processes, such as volcanic activity and permafrost melting. Once released,62

mercury poses risks to human health and the environment. In recent years, more mercury has beenreleased through human activities, such as the combustion of fuels, mining activities, and theconsumption of mercury-added products. Mercury is a trace element found in many minerals andfuels such as coal, natural gas, oil, non-ferrous ore. Mercury emitted to the atmosphere remains fora long time and will be transported long distances. Atmospheric mercury is gradually oxidized anddeposited in the ocean or on land. Inorganic mercury in water bodies can be methylated by microbialactivity, and bioaccumulated in biota at higher trophic levels. Eventually, fishing brings mercury backto human society through consumption. Excessive exposure to mercury, especially methylmercury,will pose risk to vulnerable population and pregnant women, in particular, as the methylmercury
actively passes through placenta barrier by amino acid transporter to fetus.
Similar to mercury usage, the largest mercury emission source is ASGM, which disproportionallyaffects marginalised and less privileged groups, such as children and women of child-bearing age.
Asia, Africa, Latin America and the Caribbean are the regions emitting large amounts of mercury as
shown in Figure 8. The burning fossil of fuel and the production of cement and non-ferrous metals
all removes mercury from the soil and emit it to the atmosphere. More importantly, such mercury
by-product might increase with the economic development of developing countries.

Large-scale
gold
production
4%

North MiddleAmerica east
2%
EU
2%
4%
CIS & nonOceania
EU Europe
0.4%
6%

Production offerrous metals
2%
Others
6%

Waste
7%
Cementproduction
10%
Production of
non-ferrous
metals
11%

ASGM
38%

Total 2220 tons
(2015)

Fossil fuelburning
22%

Latin
America &Caribbeans
20%

Total 2220 tons
(2015)

Asia
49%

Africa17%

Source: United Nations Environment Programme (2019). Global mercury assessment 2018.

Figure 8 Global atmospheric mercury emissions by sector and by region634.6 Reference literatures and websites
Due to the Minamata Convention, a lot of literatures on mercury data are published from many
countries. The Minamata Convention and the UNEP Global Mercury Partnership provide platforms
to access relevant information.

Mercury science and assessments
Basic mercury science
Japan Public Health Association (2001). Preventive Measures against Environmental Mercury Pollution and Its
Health Effects, October 2001. http://nimd.env.go.jp/english/kenkyu/docs/manual.pdf. Accessed 10 February
2022.
Japan, National Institute for Minamata Disease (2013). Mercury and health V4.1.
http://nimd.env.go.jp/english/kenkyu/docs/Mercury_and_health.pdf. Accessed 10 February 2022.
United Nations Environment Programme (2022). Global mercury monitoring. https://www.unep.org/exploretopics/chemicals-waste/what-we-do/mercury/global-mercury-monitoring. Accessed 15 August 2022.

Assessment reports
Arctic Monitoring and Assessment Programme and United Nations Environment Programme (2019).
Technical Background Report for the Global Mercury Assessment 2018. Tromsø: AMAP Secretariat, The FramCentre. Geneva: UN Environment Programme Economy Division.
https://wedocs.unep.org/bitstream/handle/20.500.11822/29831/gma_tech.pdf. Accessed 8 April 2022.
United Nations Environment Programme (2002). Global mercury assessment. Geneva: UNEP Chemicals.
https://wedocs.unep.org/bitstream/handle/20.500.11822/12297/final-assessment-report-25nov02.pdf.
Accessed 14 February 2022.
United Nations Environment Programme (2013). Global mercury assessment, source, emissions, releases andenvironmental transport. Geneva: UNEP Chemicals Branch.
https://wedocs.unep.org/bitstream/handle/20.500.11822/7984/-Global%20Mercury%20Assessment201367.pdf. Accessed 14 April 2022.
United Nations Environment Programme (2017). Global mercury supply, trade and demand. Geneva: UN
Environment Economy Division.
https://wedocs.unep.org/bitstream/handle/20.500.11822/21725/global_mercury.pdf. Accessed 10 February2022.
United Nations Environment Programme (2019). Global mercury assessment 2018. Geneva: UN Environment
Programme Economy Division.
https://wedocs.unep.org/bitstream/handle/20.500.11822/27579/GMA2018.pdf. Accessed 10 February
2022.

Legal frameworks on mercury
Minamata Convention
Minamata Convention (2013). Text of the Minamata Convention on Mercury for adoption by the Conference ofPlenipotentiaries. UNEP(DTIE)/Hg/CONF/3.

64

https://www.mercuryconvention.org/sites/default/files/documents/working_document/CONF_3_Minamata_Convention_on_Mercury_final_26_08_e.pdf. Accessed 21 July 2022.

Mercury standards
European Union (2006). Maximum levels for certain contaminants in food stuffs. Commission Regulation(EC) No 1881/2006. https://eurlex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2006:364:0005:0024:EN:PDF. Accessed 5 August 2022.
European Union (2013). Priority substances in the field of water policy. Directive 2013/39/EU. https://eurlex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32013L0039&from=EN. Accessed 5 August 2022.
Japan, Inter-Ministerial Coordination Council on the Minamata Convention on Mercury (2017). National
implementation plan for preventing environmental pollution of mercury and mercury compounds.
https://www.mercuryconvention.org/sites/default/files/documents/national_implementation_plan/Japan_N
IP_EN.pdf. Accessed 3 January 2022.
Japan, Ministry of Health and Welfare (1973). Provisional mercury levels in fish. Notice from Ministry of the
Health and Welfare, Japan [In Japanese].
https://www.mhlw.go.jp/web/t_doc?dataId=00ta5730&dataType=1&pageNo=1. Accessed 6 August 2022.
Japan, Ministry of Health, Labour and Welfare (2020). Ministerial ordinance on water quality standards [InJapanese]. https://elaws.e-gov.go.jp/document?lawid=415M60000100101. Accessed 6 August 2022.
Japan, Ministry of Labour (1988). Working environment standards. Notification of Ministry of the Labour,
Japan 79 [In Japanese].
https://www.mhlw.go.jp/web/t_doc_keyword?dataId=74088000&dataType=0&keyword=%E4%BD%9C%E6%A
5%AD%E7%92%B0%E5%A2%83%E8%A9%95%E4%BE%A1%E5%9F%BA%E6%BA%96&mode=0&pageNo=1.
Accessed 6 August 2022.
Joint FAO/WHO Expert Committee on Food Additives (2007). 4.3 Methylmercury, In Evaluation of certain foodadditives and contaminants. sixty-seventh report of the joint FAO/WHO Expert Committee on Food Additives.
WHO technical report series 940, 53-61.
http://apps.who.int/iris/bitstream/handle/10665/43592/WHO_TRS_940_eng.pdf. Accessed 3 January 2022.
Niu, S., Colosio, C., Carugno, M. and Adisesh, A. (eds.) (2022). 1.1.7 Diseases caused by mercury or its
compounds, In Diagnostic and exposure criteria for occupational diseases, Guidance notes for diagnosis andprevention of the diseases in the ILO List of Occupational Diseases (revised 2010). 56-62. International Labour
Organization: Geneva. https://www.ilo.org/wcmsp5/groups/public/---ed_dialogue/--lab_admin/documents/publication/wcms_836362.pdf. Accessed 5 August 2022.
United States of America, Environmental Protection Agency (2000). New source performance standards for
new small municipal waste combustion units. Federal Register 65(235). 76350-76375.
https://www.govinfo.gov/content/pkg/FR-2000-12-06/pdf/00-30003.pdf. Accessed 6 August 2022.
Unites States of America, Environmental Protection Agency (2001a). Water quality criteria: notice ofavailability of water quality criterion for the protection of human health: Methylmercury. Federal Register66(5). 1344-1359. https://www.govinfo.gov/content/pkg/FR-2001-01-08/pdf/01-217.pdf. Accessed 6 August2022.
United States of America, Environmental Protection Agency (2001b). Methylmercury (MeHg); CASRN 2296792-6. In Integrated Risk Information System (IRIS), Chemical assessment summary.
https://cfpub.epa.gov/ncea/iris/iris_documents/documents/subst/0073_summary.pdf. Accessed 6 August2022.
United States of America, Environmental Protection Agency (2006). Standards of performance for new
stationary sources and emission guidelines for existing sources: large municipal waste combustors; Finalrule. Federal Register 71(90). 27324-27348. https://www.govinfo.gov/content/pkg/FR-2006-05-10/pdf/064197.pdf. Accessed 6 August 2022.

65

United States of America, Environmental Protection Agency (2009). National primary drinking water
regulations. https://www.epa.gov/sites/default/files/2016-06/documents/npwdr_complete_table.pdf.
Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2011a). Standards of Performance for New
Stationary Sources and Emission Guidelines for Existing Sources: Sewage Sludge Incineration Units. Federal
Register 76(54). 15372-15454. https://downloads.regulations.gov/EPA-HQ-OAR-2009-05590148/content.pdf. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2011b). Final rule to reduce mercury emissions
from gold mine ore processing and production sources, Fact sheet.
https://www.epa.gov/sites/default/files/2016-01/documents/gold_mines_fs_121610.pdf. Accessed 6
August 2022.
United States of America, Environmental Protection Agency (2012). National emission standards forhazardous air pollutants for the Portland cement manufacturing industry and standards of performance forPortland cement plants. Federal Register 78(29). 10006-10054. https://www.govinfo.gov/content/pkg/FR2013-02-12/pdf/2012-31633.pdf. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2013). Federal plan requirements for
hospital/medical/infectious waste incinerators constructed on or before December 1, 2008, and standardsof performance for new stationary sources: hospital/ medical/ infectious waste incinerators. Federal
Register 78(92). 28052-28078. https://www.govinfo.gov/content/pkg/FR-2013-05-13/pdf/2013-09427.pdf.
Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2016a). National emission standards forhazardous air pollutants from coal- and oil-fired electric utility steam generating units and standards ofperformance for fossil-fuel-fired electric utility, industrial-commercial institutional, and small industrialcommercial-institutional steam generating units, technical correction. Federal Register 81(66). 20172-20207.
https://www.govinfo.gov/content/pkg/FR-2016-04-06/pdf/2016-06563.pdf. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2016b). Standards of performance for pew
stationary sources and emission guidelines for existing sources: commercial and industrial solid waste
incineration units. Federal Register 81(121). 40956-41034. https://www.govinfo.gov/content/pkg/FR-201606-23/pdf/2016-13687.pdf. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2018). Part 503 standards for the use of
disposal of sewage sludge, Protection of environment. In Code of federal regulations.
https://www.govinfo.gov/content/pkg/CFR-2018-title40-vol32/xml/CFR-2018-title40-vol32-part503.xml.
Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2020). National emission standards forhazardous air pollutants: coal- and oil-fired electric utility steam generating units—Subcategory of certain
existing electric utility steam generating units firing eastern bituminous coal refuse for emissions of acidgas hazardous air pollutants. Federal Register 85(73). 20838-20855.
https://www.govinfo.gov/content/pkg/FR-2020-04-15/pdf/2020-07878.pdf. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2022a). National recommended water quality
criteria - Aquatic life criteria table. https://www.epa.gov/wqc/national-recommended-water-quality-criteriaaquatic-life-criteria-table#table. Accessed 6 August 2022.
United States of America, Environmental Protection Agency (2022b). Part 261.24 toxicity characteristic.
Characteristics of hazardous waste. In Code of federal regulations. https://www.ecfr.gov/current/title40/chapter-I/subchapter-I/part-261/subpart-C. Accessed 6 August 2022.
United States of America, Food and Drug Administration (2000). Guidance for industry: Action levels forpoisonous or deleterious substances in human food and animal feed. https://www.fda.gov/regulatoryinformation/search-fda-guidance-documents/guidance-industry-action-levels-poisonous-or-deleterioussubstances-human-food-and-animal-feed#merc. Accessed 6 August 2022.

66

World Health Organization (2000). 6.9 Mercury, In Air quality guidelines for Europe. Second edition.
Copenhagen: WHO Regional Publication. 157-161.
https://www.euro.who.int/__data/assets/pdf_file/0004/123079/AQG2ndEd_6_9Mercury.PDF. Accessed 14
February 2022.
World Health Organization (2021). Preventing disease through health environments, Exposure to mercury: amajor public health concern, Second edition. World Health Organization: Geneva.
https://apps.who.int/iris/rest/bitstreams/1341885/retrieve. Accessed 5 August 2022.

Analytical methodologies and guidelines
Japan, Ministry of the Environment (2004). Mercury analysis manual. March 2004, Ministry of theEnvironment, Japan. http://nimd.env.go.jp/kenkyu/docs/march_mercury_analysis_manual(e).pdf. Accessed
27 June 2022.
World Health Organization (2018). Standard operating procedure for assessment of mercury in human scalp
hair, In Assessment to prenatal exposure to mercury: standard operating procedures. Copenhagen: WHO
Regional Publication. 33-70https://apps.who.int/iris/bitstream/handle/10665/332161/WHO-EURO-2020430-40165-53693-eng.pdf. Accessed 14 February 2022.

Cross-cutting issues
InforMEA (2022). Mercury and gender. https://elearning.informea.org/course/view.php?id=99. Accessed 28
September 2022.
Strategic Approach to International Chemicals Management (2017). Gender and the sound management ofchemicals and waste. SAICM/IP.2/6.
http://www.saicm.org/Portals/12/documents/meetings/IP2/IP_2_6_gender_document.pdf. Accessed 11
August 2022.
United Nations Environment Programme (2016). Global Gender and Environment Outlook, The Critical
Issues. United Nations Environment Programme, Nairobi, Kenya.
https://wedocs.unep.org/bitstream/handle/20.500.11822/7628/Global_gender_and_environment_outlook_The_critical_issues-2016ggeo_summary_report.pdf.pdf.
Accessed 11 August 2022.
United Nations Environment Programme and Minamata Convention (2021). Gender equality and mercury.
Minamata Convention on Mercury Secretariat.
https://www.mercuryconvention.org/sites/default/files/documents/202108/Gender_Equality_Mercury_May_2021.pdf. Accessed 11 August 2022.

Other
International Organization for Standardization (2015) Quality management systems – Fundamentals andvocabulary. ISO 900:2015. https://www.iso.org/obp/ui/#iso:std:iso:9000:ed-4:v1:en. Accessed 29 October
2022.
Joint Committee for Guides in Metrology (2008). Guide to the expression of uncertainty in measurement.
JCGM 100: 2008. https://www.iso.org/sites/JCGM/GUM/JCGM100/C045315e-html/C045315e.html.
Accessed 29 October 2022.
Joint Committee for Guides in Metrology (2012). International vocabulary of metrology – Basic and general
concepts and associated terms (VIM). 3rd edition, JCGM 200:2012.

67https://www.bipm.org/documents/20126/2071204/JCGM_200_2012.pdf/f0e1ad45-d337-bbeb-53a615fe649d0ff1. Accessed 21 July 2022.
United Nations Institute for Training and Research (2020). Guiding questions for designing leaning events(face-to-face and online). United Nations Institute for Training and Research.
https://unitar.org/sites/default/files/media/file/Designing%20Learning%20Events.pdf. Accessed 14
February 2022.

684.7 Glossary, acronyms, and abbreviations
AAS
AC
AIT
ASGM
BAT
BEP
BMDL
Btu
bw
CAS
COP
CRM
CVAAS
CVAFS
DC
DDNP
dscm
dw
ECD
EGU
EMC
EMS
ETDA
EU
FY
GC
GEF
GEM
GOM
GUM
IDEA
IEC
IGCC
ILO
lb
ISO
JCGM
JECFA
LED
LOD
LOQ
MOEJ
MOHLWJ

Atomic absorption spectrometry
Alternate current
Asian Institute of Technology
Artisanal and small-scale gold mining: gold mining conducted by individual miners or
small enterprises with limited capital investment and production.
Best Available Techniques: Techniques that are the most effective to prevent and, wherethat is not practicable, to reduce emissions and releases.
Best Environmental Practices: Application of the most appropriate combination ofenvironmental control measures and strategies.
Benchmark dose limit
British thermal unit = 0.293 Wh
Body weight
Chemical Abstracts Service
Conference of the Parties
Certified reference material
Cold-vapour atomic absorption spectrometryCold-vapour atomic fluorescence spectrometry
Direct current
Diazodinitrophenol
Dry standard cubic metre: Amount of gas free of water vapour at a temperature of 20 °C
and a pressure of 101325 Pa.
Dry weight
Electron capture detector
Electric utility steam generating unit
Indonesia, Environmental Monitoring Centre
Environmental management system
Ethylenediaminetetraacetic acid
European Union
Fiscal year
Gas chromatography
Global Environment Facility
Gaseous elementary mercury
Gaseous oxidized mercury
Guide to the expression of uncertainty in measurement
IDEA Consultants
International Electrotechnical Commission
Integrated gasification combined cycle
International Labour Organization
Pound = 454 g
International Organization for Standardization
Joint Committee for Guide in Metrology
Joint FAO/WHO Expert Committee on Food Additives
Light-emitting diode
Limit of detection
Limit of quantification
Japan, Ministry of the Environment
Japan, Ministry of the Health, Labour and Welfare

69

MOHWJ
MOLJ
MOYAI
Initiative
NAP
NIMD
NOEL
NOx
OECC
PDCA
PE
PP
PTWI
QA
QC
QMS
RM
ROAP
SAICM
SMSA
S/N
SOP
SOx
UN
UNEP
UNITAR
UPC
USEPA
USFDA
UV
WHO
wt
ww
XRF

70

Japan, Ministry of the Health and Welfare
Japan, Ministry of the Labour
A Japan’s commitment made at the Diplomatic Conference in 2013 to support
developing countries and to promote voices and messages from Minamata.
National action plan
National Institute for Minamata Disease
No-observed-effect level
Nitrogen oxides
Overseas Environmental Cooperation Center
Plan, do, check and action
Polyethylene
Polypropylene
Provisional tolerable weekly intake
Quality assurance
Quality control
Quality management system
Reference material
Regional Office for Asia and the PacificStrategic Approach to International Chemicals Management
Standard metropolitan statistical area
Signal/NoiseStandard operating procedure
Sulphuric oxides
United Nations
United Nations Environment Programme
United Nations Institute for Training and Research
University of South PacificUnited States of America, Environmental Protection Agency
United States of America, Food and Drug Administration
Ultraviolet
World Health Organization
Weight
Wet weight
X-ray fluorescence analyser

5 EDITABLE POWERPOINT FILESThis Chapter provides the reading scripts of pre-recorded narration embedded in the multi-media
files.

5.1 List of slide decks
Lecture 1: Physical and chemical properties, usage, and environmental behaviour (29 slides,
24’58”)
▪
▪
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Section 1: Physical and chemical properties of mercury (4 slides, 3’32”)
Section 2: Mercury products and uses (3 slides, 1’55”)
Section 3: Use of elemental mercury (5 slides, 4’47”)
Section 4: Use of amalgam (5 slides, 4’26”)
Section 5: Use of mercury compounds (8 slides, 7’43”)
Section 6: The global mercury cycle and emissions (3 slides, 2’16”)

Lecture 2: Atmospheric survey and analysis (manual active sampling method) (59 slides,
61’24”)Part I: Sample collection (33 slides, 35’01”)▪
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Section 1: Outlines of atmospheric mercury survey (4 slides, 5’40”)
Section 2: Sampling equipment and its preparation (9 slides, 8’01”)
Section 3: Atmospheric sample collection (12 slides, 10’39”)
Section 4: Atmospheric surveys in special situation (7 slides, 10’30”)

Part II: measurement, data processing and QA/QC (25 slides, 26’09”)▪
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Section 1: Measurement of gold amalgamation cartridge (3 slides, 3’00”)
Section 2: CVAAS measurement (6 slides, 8’06”)
Section 3: Data processing and QA/QC (8 slides, 7’43”)
Section 4: Maintenance and calibration methods (7 slides, 7’08”)

Lecture 3: Solid sample (soil, sediment, and biota) survey and analysis (38 slides, 40’21”)
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Section 1: Key characteristics of soil and sediment (3 slides, 3’00”)
Section 2: Soil sample collection (5 slides, 5’57”)
Section 3: Sediment sample collection (4 slides, 3’28”)
Section 4: Biota sample (2 slides, 1’26”)
Section 5: Total mercury analysis (9 slides, 9’23”)
Section 6: Measurements, data processing, and QA/QC (9 slides, 9’36”)
Section 7: Other methods for total mercury analysis (5 slides, 7’18”)71

Lecture 4: Water sample survey and analysis (30 slides, 28’02”)▪
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Section 1: Key characteristics of water for mercury survey and analysis (3 slides, 4’03”)
Section 2: Water sample collection (8 slides, 7’55”)
Section 3: Total mercury analysis for water sample (14 slides, 12’02”)
Section 4: Quality control - Reducing operation blank level (4 slides, 3’54”)

Lecture 5: Human biological sample analysis (18 slides, 20’10”)▪
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Section 1: Key characteristics of human biological samples (4 slides, 5’29”)
Section 2: Hair sample collection (3 slides, 2’56”)
Section 3: Total mercury analysis for human biological samples (10 slides, 11’15”)

Lecture 6: Methylmercury analysis (15 slides, 11’27”)▪
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Section 1: Key features of methylmercury surveys (4 slides, 3’22”)
Section 2: Methylmercury analysis (7 slides, 5’38”)
Section 3: Methylmercury analysis for human hair samples (3 slides, 2’10”)

Lecture 7: Mercury monitoring and the Minamata Convention (24 slides, 18’28”)
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Section 1: Outlines of the Minamata Convention (4 slides, 3’33”)
Section 2: Measures to reduce mercury risks (8 slides, 7’09”)
Section 3: Provisions facilitating the implementation of measures (4 slides, 3’09”)
Section 4: Overall management of the Convention (3 slides, 1’32”)
Section 5: Contribution of mercury monitoring to the Convention (4 slides, 2’50”)

Lecture 8: Quality management (47 slides, 47’22”)
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Section 1: Outline of TQM, QA, and QC (7 slides, 5’46”)
Section 2: SOP and record: Process clarity (9 slides, 11’07”)
Section 3: QA/QC analysis of samples: Result validity (9 slides, 13’13”)
Section 4: Quality of data: Bias and uncertainty (6 slides, 5’14”)
Section 5: Bias of data (3 slides, 1’34”)
Section 6: Uncertainty (12 slides, 10’11”)

Lecture 9: Laboratory safety and environmental management (23 slides, 21’49”)
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72

Section 1: Safe laboratory operation (3 slides, 1’11”)
Section 2: Safe handling of hazardous reagents (7 slides, 9’56”)
Section 3: Apparatus and equipment safety (5 slides, 3’26”)
Section 4: Environmental management (4 slides, 3’17”)
Section 5: ISO 14001 environmental management standard (3 slides, 3’34”)

5.2 Lecture 1 Physical and chemical
properties, usage, and environmental
behaviour‘0’ This lecture explains the basic scientific knowledge such as physical and chemical properties,
usage, and environmental behaviour of mercury, which will help in understanding mercury issues.

Section 1: Physical and chemical properties of mercury‘1’ This section explains the physical and chemical properties of mercury.
‘2’ Mercury is a chemical element that exists in various forms. With an atomic number of 80, which
is next to gold, mercury is the only metal element that exists in liquid form at normal temperatures.
In addition, mercury has a low boiling point among metallic elements, and it is volatile with a highvapour pressure. The abundance of mercury in Earth’s crust is similar to that of silver, but mercury
has a much lower market price than precious metals.
‘3’ Methylmercury is a mercury compound of great concern due to its high toxicity. Methylmercury
binds to cysteine, a kind of amino acid, to form a complex with a molecular structure similar tomethionine, an essential amino acid. Due to this similarity, the complex is actively absorbed via anamino acid transporter. Then, it is incorporated into body tissues made of protein, including the brain
and fetus.
‘4’ Most mercury and mercury compounds have certain toxicities, but their biological behaviours
and toxicity levels differ. The absorption rates of inhaled elementary mercury and ingested
methylmercury are very high, while the absorption rate of inorganic mercury is rather low. Ingested
elemental mercury is usually directly excreted without absorption. Absorbed mercury is gradually
oxidized and excreted in urine as inorganic mercury. Elemental mercury passes through the bloodbrain barrier and causes mercury poisoning of the central nervous system. Accidental high-level
exposure to mercury vapour in the workplace can be fatal, but acute symptoms are usually reversible.
The symptoms of chronic low-level exposure to elemental mercury were known as mad hatter’sdisease. Methylmercury is transported actively to form body tissues made of protein. The adverse
effects depend on the body parts into which methylmercury is incorporated. Ingested inorganic
mercury causes inflammation of the digestive tract and kidney damages if the amount is very high.
Acute mercury exposure is usually treated by stimulating excretion. For chronic exposure, stopping
the exposure is the most important measure.

73Section 2: Mercury products and uses
‘5’ This section provides an overview of various applications where mercury is found in products orprocesses.
‘6’ Mercury is one of a few elements known since ancient times. It has been used for various
purposes for many thousands of years. Red pigments and the preservation of corpses are among
the oldest applications. The demand for mercury has increased as new uses have been invented
over time. The supply side, that is, mercury mining, has also been well developed to support thedemand for mercury. Today, some mercury-added products and processes have been replaced bynon-mercury alternatives, but many are still widely used globally. The Minamata Convention controls
the products and processes stipulated in the Annexes, but even after phase out, mercury waste willcontinue to be generated for a long time. Thus, proper management of mercury waste is very
important.
‘7’ Global mercury use is estimated to be approximately 4700 tons per year as of 2015. Artisanaland small-scale gold mining is the largest mercury consumer, and Asia, Africa, Latin America andthe Caribbean are the regions consuming a large amount of mercury.

Section 3: Use of elemental mercury‘8’ This section explains the applications of elemental mercury in products.
‘9’ Elemental mercury is used for measuring purposes. As a high-density liquid, it is suitable formeasuring pressure. Devices such as manometers, barometers, and sphygmomanometers enableprecise pressure measurements without using electricity. For official purposes, mmHg or inHg canstill be used as non-SI units of measurement. Mercury is also useful for measuring temperature
because it exists in liquid form in a wide temperature range. As a metallic element, mercury has ahigh thermal conductivity, which provides a quick response. These mercury-added measuring
devices are subject to phase out under the Minamata Convention.
‘10’ A discharge tube is an electronic device that contains gas or vapour at low pressure, and throughwhich conduction takes place when a high voltage is applied. The mercury arc rectifier was animportant device for converting high voltage alternating current, AC, to direct current, DC. As modern
electricity supply networks were developed with AC, rectification was required if the industry
required DC. Today, this function is mostly performed by power semiconductors. Several gaseous
elements, including mercury vapour, emit various wavelengths of light. Mercury discharges
ultraviolet ray, UV-C, which is invisible to humans. As UV-C damages DNA, mercury vapour lamps

74are used for microbial disinfection. Fluorescent lamps convert UV-C to visible light for lighting
applications. The light emitted from discharge tubes is also used for various lighting applications,such as indoor and outdoor lighting, signage, and the headlamps of vehicles.
‘11’ As mercury is electrically conductive, it is used for various electric controls. The mercury switch
has several advantages for closing and opening electrical circuits. As the contact surface isconcealed, no oxidation occurs, and the surface remains clean with a low resistance due to thewetting nature of mercury. Application includes tilt switches to activate lights on the boot lids ofvehicles, rollover warning devices for vending machines, anti-lock braking systems that detects
acceleration force, high-speed switches as mercury relay does not cause chattering, and mercury
slip rings that transmit signals or power to devices over 360° of rotation. Mercury is added tobatteries for safety purposes to prevent hydrogen gas generation. Abnormal reactions at the zincanode causes cell rupture or leakage, but mercury inhibits such abnormal reactions. Although mostdry cells have stopped using mercury, a few types of button cells still use mercury for this purpose.
Lithium coin cells do not use water as the electrolyte, so no mercury is added.
‘12’ Elemental mercury is also used for many other purposes. Some are being phased out as nonmercury alternatives are becoming increasingly available. It is important to be aware that not alluses of mercury are subject to the Minamata Convention, so legitimate uses of mercury will remain.

Section 4: Use of amalgam‘13’ This section explains the applications of amalgam in products or processes.
‘14’ Mercury can form various alloys with other metals, which are called amalgam. Amalgam has
been an important material for many industries as final products or in production processes. Dental
amalgam is a mixture of silver and tin powder, which is gradually hardened to fill dental cavities. Tin
amalgam was used for the reflective surfaces of mirrors.
‘15’ Gold and silver extraction and refining have been practised for many thousands of years. The
oldest method called cupellation used lead and was invented in the BC era. There was a risk for leadpoisoning with this method. The amalgamation method was then invented in the 16th century, whensilver mining in Latin America was at its peak. Due to the melting and boiling points of mercury being
lower than those of lead, the consumption of heat sources, such as firewood, was reduced, which
preserved forests in the region. The amalgamation method for ASGM accounts for the largest usageof mercury today and disproportionally affects marginalised and less privileged groups. The cyanide
method was invented in the 19th century during the Gold Rush era. This method is currently75

predominantly used for large-scale gold mining operations, but its application to ASGM is being
explored.
‘16’ NaCl, which is the chemical form of edible salt, can generate chlorine gas and caustic soda byelectrolysis. Caustic soda is used for manufacturing products such as soap and glass, and chlorine
gas is used for producing disinfection and bleaching agents as well as PVC. Mercury is used as theelectrode for the mercury-cell process, which was invented in the early 20th century and is still usedin some countries. Chlorine ions are oxidized at the anode and become chlorine gas. On the cathodeside, where mercury is used, sodium ions are reduced to metallic sodium, which forms an amalgam
with mercury. The sodium amalgam is then sent to an amalgam decomposer, where caustic soda
is formed. The key to this electrolysis process is blocking sodium backflow to the anode side. The
diaphragm process physically blocks this backflow with the fibrinous structure of asbestos. Thissystem is still used, but the risk of asbestos is a concern. The membrane process has a similar
configuration to the diaphragm process, but an ion exchange membrane allows the selective
permeation of sodium ions to the cathode side, which is more energy efficient and avoids toxic
substances.
‘17’ Special applications of amalgam includes low-temperature thermometers with thallium
amalgam, which is a melting temperature of approximately minus 60 °C. However, mercury is
problematic in the oil and gas sector. Mercury erodes aluminium equipment, such as heatexchangers, and inactivates palladium-based catalysts.

Section 5: Use of mercury compounds‘18’ This section explains the applications of mercury compounds in products or processes.
‘19’ Mercury sulphide is naturally found as cinnabar, which exists as blood red crystals or dark red
stones. Red is one of the oldest colours that humans have intentionally used since the pre-historicera. Three major red pigments have been used. Iron oxide provides brownish red and is easily
available from red clay soil. By contract, mercury sulphide needs laborious refinement from ore, so
it was an expensive pigment. It can also be synthesized from mercury and sulphur. Due to its
preciousness, mercury sulphide was used for more important occasions, such as ceremonial andreligious purposes. Lead oxide is also a synthesized pigment with a bright orange colour.
‘20’ Cosmetics also use colour, which are predominantly consumed by women. Red, white, and black
are the three base colours for cosmetics. Red pigments, such as cinnabar, were used for
bodypainting in some indigenous societies. More broadly, white face powder has been used for
makeup. Calomel, mercury (I) chloride, is a white powder used for such purposes. Other chemicals,

76

including lead white and talc, have also been used. Lead poisoning by face powder was problematicin the past few centuries. Currently, concerns have been raised about talc, which contains asbestos
as an impurity. Mercury use for skin-whitening cream is another concern, as it is still widely used
globally. The preference to lighter coloured skin is still prevalent in many countries where the skincare industry keeps feeding illegal products into market.
‘21’ The biocidal action of mercury is used for fungicides and preservatives. Organic mercury
compounds such as phenylmercury have been used for seed dressing, as fungicides for crops suchas rice and wheat. Among inorganic mercury compounds, mercury chloride has been used for woodpreservation and red mercury oxide has been used for anti-fouling ship paint. In some products thatare directly applied to humans, mercury compounds are still used as preserving agents. For example,
thiomersal preserves vaccines at normal temperatures, which is important when providing vaccines
to remote areas where no cold chain is available.
‘22’ Mercury has been used in pharmaceuticals since ancient times. Traditional Chinese andAyurveda medicines still include mercury products. One of the most significant historical uses of
mercury for pharmaceutical purposes is the treatment of syphilis patients. Syphilis emerged in thelate 15th century and rapidly spread over the globe. Many types of mercury compounds were used
for medical treatment from the 16th century until being replaced by penicillin in the 1940s.
Mercurochrome is a water solution of the organic mercury compound merbromin, which wasinvented in the early 20th century and has been widely used for treating minor wounds. Its lesspainful nature and cheap price allowed various applications in both clinical and household settings.
Mercury inhibits the growth of microorganisms. This characteristic has been used for many
preservation and antiseptic purposes.
‘23’ A catalyst is a substance that facilitate or accelerates a chemical reaction, but its form remains
unchanged. The elements in the zinc group, which includes mercury, have been used as catalysts
for organic synthesis, particularly for the production of vinyl polymers by accelerating addition
reactions from acetylene. The catalysts form intermediate compounds to promote addition
reactions. Minamata disease was caused by the mercury catalyst used for acetaldehyde production,
which was methylated in the factory and then released into the environment. To avoid the use of
mercury, ethylene can be used for the feedstock instead of acetylene. Another type of catalyst is theinitiator for polymerising polyurethane elastomer, which triggers the process in moulded products
or coatings. Although mercury acts as a catalyst for this process, it remains in the final product.
‘24’ Batteries, especially chemical batteries, utilize the oxidation and reduction of chemicalcompounds to store electricity. The mercury cell is a type of battery that has a mercury oxide
cathode. Once electricity is consumed, mercury oxide is reduced to metallic mercury, which flows

77

out of the cathode. This product is subject to phase out under the Convention. However, mercury
use for research, calibration, and reference is exempt from the Convention, so standard cells suchas the Weston cell are not subject to phase out.
‘25’ Various mercury compounds are used for many other purposes. One of historical uses ismercury (II) nitrate for hat making. A process called ‘carroting’ was extensively used for the
preparation of felt. Mercury (II) fulminate was also an important mercury compound used
extensively during wars as a material for the detonation caps of explosives. A new use has been
examined for mercury (II) sulphide for the final disposal of mercury waste because stabilisation isrequired in some countries to dispose of mercury.

Section 6: The global mercury cycle and emissions‘26’ This section explains the global mercury cycle and emissions.
‘27’ As a chemical element, mercury has existed on Earth since its creation. Mercury is released
from natural sources by processes such as volcanic activity and permafrost melting. Once released,
mercury poses risks to human health and the environment. In recent years, more mercury has beenreleased through human activities, such as the combustion of fuels, mining activities, and theconsumption of mercury-added products. Mercury emitted to the atmosphere remains for a longtime and will be transported long distances. Atmospheric mercury is gradually oxidized anddeposited in the ocean or on land. Inorganic mercury in water bodies can be methylated by microbialactivity and bioaccumulated in biota at higher trophic levels. Eventually, fishing brings mercury backto human society through consumption.
‘28’ Similar to mercury usage, the largest mercury emission source is ASGM, which disproportionallyaffects marginalised and less privileged groups, such as children and women of child-bearing age.
Asia, Africa, and Latin America and the Caribbeans are the regions emitting large amounts ofmercury. The burning of fossil fuel and the production of cement and non-ferrous metals all remove
mercury from the soil and emit it into the atmosphere. More importantly, such mercury by-productmight increase with the economic development of developing countries.

785.3 Lecture 2 Atmospheric survey andanalysis (manual active sampling
method)‘0’ This lecture discusses atmospheric survey and analysis particularly the manual active sampling
method using gold amalgam trap cartridge.

Part I: Sample collection‘1’ This part describes sample collection for the manual active sampling method of atmosphericmercury monitoring.

Section 1: Outlines of atmospheric mercury survey‘2’ This section explains three methods that are often used in atmospheric mercury monitoring.
‘3’ This slide shows the survey scene using the three survey methods for atmospheric mercury
monitoring. Atmospheric mercury survey methods are subdivided into the following three methods
depending on how mercury is collected and measured. They are automated active sampling method,manual active sampling method, and passive sampling method.
In the automated active sampling method, mercury in the atmosphere is automatically collected andmeasured by a dedicated device that continues to measure mercury at regular intervals. The
advantages of this method are the ability of continuous monitoring in a very short cycle to get realtime data continuously. The equipment is commercially available and can speciate mercury into
three types depending on physiochemical properties, namely, elemental mercury, oxidized mercury,and particle-bound mercury. However, the equipment is expensive, and the operation requires
sufficient skills and experiences.
In the manual active sampling method, the collection material and air pump are brought to the survey
sites. Mercury is adsorbed on to the collection material on site, and then the analysis is performedin the laboratory. This method can monitor mercury with a very small, lightweight, and inexpensive
device. The sampling time, which is the survey interval, is longer than that of the automated active
sampling method, but shorter than the passive sampling. It is often approximately 24 hours forambient monitoring.

79

In the passive sampling method, mercury is collected using a passive sampler that adsorbs mercury
in the atmosphere naturally without using a pump or other devices and it follow diffusion process inatmosphere through sulphur coated charcoal. After collection, analysis is performed in thelaboratory in the same way as in the manual active sampling method. It is very easy to installsamplers on site, which makes simultaneous surveys of a large number of points possible. The
sampling period is often several weeks to one month, which is longer than those of the other two
methods as it is less time sensitive.
Each of these methods has its own strengths and weaknesses, so it is necessary to use a methodthat is suitable for the purpose of the survey.
‘4’ The manual active sampling method is outlined, and the tools and devices used for this method
are explained. This explanation is based on the manual active sampling method used for hazardous
air pollutant survey in Japan, which uses gold-coated particles as a mercury trap. The manual active
sampling method can be introduced with relatively inexpensive devices and less training. Besides
that, because it is easy to handle, it can be applied in many sampling locations.
‘5’ This is a schematic diagram of the collection system for atmospheric mercury by manual active
sampling method. It is configured with a gold amalgamation cartridge, a pump to draw air, a soda
lime trap to filter out interferents, and connecting pipes. The principle is simple: the gold
amalgamation cartridge is used as an adsorbent, and air is sucked by the pump to be fed throughthe adsorbent. When the air passes through the adsorbent, mercury in the air forms an amalgam
with gold in the adsorbent and is taken up by the adsorbent. The mercury collected as gold amalgam
is very stable and can be easily transported and stored at room temperature. This mercury can thenbe extracted by heating the adsorbent. In the laboratory, the mercury expelled by heating theadsorbent is introduced into an analytical instrument for measurement. Gold cartridges that havebeen analysed can be reused for another survey.

Section 2: Sampling equipment and its preparation‘6’ This section provides an overview of the equipment used for sample collection and the operations
for its preparation.
‘7’ This slide shows the equipment required to collect samples for mercury in air using the manual
active sampling method. The equipment required includes gold amalgamation trap cartridges, trap
tubes filled with soda lime, air pumps, tubes, and pipes. A thermometer, hygrometer and barometerare also useful when making temperature and pressure corrections to the volume of air sucked.

80‘8’ Firstly, the gold amalgamation trap, which is the adsorbent, is described. The adsorbent in thesurveys consists of particles with gold coated on their surfaces contained in a quartz tube with an
inner diameter of four mm. The collection capacity of mercury in the air is quantitative in most cases.
The adsorbent can be used repeatedly, so the operational cost is very low.
‘9’ This slide describes the preparation of gold trap cartridges prior to the survey. Needless to say,the gold cartridges used for the survey must be free from mercury. Mercury can be removed fromthe gold cartridges by heating, so the cartridges can be cleaned after they are analysed using ananalytical instrument. However, once cleaned, the cartridges gradually absorb mercury from theatmosphere if they are left open. They should therefore be kept in a tightly sealed container duringstorage and transport. The same applies after the samples have been collected. Even if the sample
is kept in a tightly sealed container, it could gradually absorb mercury over a long storage time.
During transport and storage, the sample might be exposed to an environment with unexpectedly
high mercury concentrations. It is therefore recommended that separate cartridges are prepared forfield blank testing to evaluate the unintentional absorption of mercury.
‘10’ This is a soda lime trap for removing interfering substances. Moisture, halogens and nitrogenoxides present in air have an adverse effect on mercury analysis. The soda lime absorbs many ofthese substances and reduces the interference with the measurement.
‘11’ This slide shows the preparation of a soda lime trap. A short fluoropolymer pipe, just large
enough to fit a gold cartridge, is prepared. One end of the pipe is filled with quartz wool, and thenthe pipe is filled with soda lime from the other end. Preparation is completed by filling the other endof the pipe with quartz wool. The amount of interfering substances that the soda lime can absorb
depends on the environmental conditions and the soda lime used. As soda lime is a relatively
inexpensive reagent, the soda lime trap should be replaced with a new one every time a sample iscollected.
‘12’ This slide shows an example of a pump that is commonly used in the manual active sampling
methods. Most air suction pumps can be used, as long as they draw air stably. The gold cartridge
method uses a flow rate of approximately 0.5 litres per minute, which means that even a very small
pump is sufficient. The low power consumption also means that many pumps can be run on battery
power alone, without an external power supply. In addition to the pump, a flow integrator is required
to record the flow rate. If using volumetric flow controllers, the temperature and pressure must berecorded separately to convert the flow rate to standard conditions. This is unnecessary with mass
flow controllers, as the conversion is done automatically. Some pumps are equipped with a mass
flow controller, which allows the survey to be carried out in a very small space. However, pumps are81usually not waterproof and do not operate properly at extremely high or low temperature. For thisreason, they must be stored in a shelter or case during the survey.
‘13’ The tubes connecting the gold cartridge to the pump should be clean, free of holes and cracks,
and able to connect devices without air leakage. As the tube is connected to the leeward side of theadsorbent, the air that passes through the tubing does not enter the adsorbent. Thus, various
materials other than glass or fluoropolymer can be used. It is sufficient to prepare the tube by rinsing
with clean water, drying, and storing in a plastic bag to prevent dusts. It is not necessary to clean
the tube with acids.
‘14’ The picture on this slide shows a small multi-functional data logger that can measure and record
temperature, humidity and barometric pressure, which is suitable for survey sites. If the samplingflow is measured with a mass flow controller, the temperature and pressure at the time of the survey
are not absolutely necessary, but they still provide important information for understanding theconditions at the time of the survey. It is helpful if a meteorological facility is in the vicinity of thesite and the data is available. If not, it is necessary to install thermometers and barometers at the
sampling site. As shown in this photo, small loggers are available on the market that can measuretemperature, humidity and pressure and record this information at regular intervals in their internal
memory.

Section 3: Atmospheric sample collection‘15’ The actual collection of atmospheric samples is explained in this section.
‘16’ If the purpose of the air quality survey is to understand the general conditions in the area, it isimportant to select a representative site. A location with no emission sources of mercury in theimmediate vicinity and where there are no special airflow patterns due to buildings or topography
should be selected. Different criterial will apply if the influence of sources is to be investigated.
‘17’ Prior to setting up the gold cartridges and other survey equipment, the survey site should be
prepared. In areas where the ground is bare soil or there is a lot of dust, covering the site with asheet is desirable to prevent adverse effect from roll-up dust. A shelter to protect the pumps fromrain and direct sunlight is also necessary. A small tent will suffice for the purpose. It is also possible
to use a container with a fan for heat removal.
‘18’ This slide shows the stand posts and pipes for supporting gold cartridges. The position of thegold cartridges should not be too low, to avoid influence from the ground surface. The monitoring
manual indicates a minimum height of 1.5 metres, which often requires the use of a stand to holdthe cartridge. It is advisable to insert the gold cartridge into a pipe that is slightly larger than itself

82

for protection from rain and dust during sampling. Many materials can be used, including plastics
such as PVC pipes, which are the easiest choice for this purpose.
‘19’ The procedure for setting up the equipment for sample collection is described. The first step isto prepare the air pump and tubing. The tube is fixed along the support and connected to the pump.
The functions of the pump are checked before sampling to ensure that the pump is working properly
and the flow rate is set correctly. Most surveys are carried out at a flow rate of approximately 0.5
litres per minute.
‘20’ Once the support and pumps are set properly, the gold cartridges are installed. Gloves should
always be worn when handling the gold cartridge. Disposable gloves are useful for this purpose. If
field blanks are being collected, the case is opened together with the gold cartridges for sampling.
Then, the gold cartridge is taken from the container and connected to the soda lime trap. The flow
direction indicated on the cartridge should be confirmed when fitting the cartridges to the tubes.
The gold cartridge connected to the tube is inserted into the protective pipe. Ideally, the cartridge
should be placed at an upright angle, but this may risk rainwater entering through the protective pipe.
For this reason, it is recommended that the upper side of the pipe is covered and that the pipe istilted slightly. In this example, the piped are covered with aluminium foil.
‘21’ After connecting the gold cartridge, pump and tubing, they are rechecked before sampling. For
example, it should be confirmed that the flow of the gold cartridges is oriented correctly, that the
tubing is securely connected without any air leakage, and that the tubes are not damaged.
‘22’ Once all the joints are properly connected, the pumps are turned on and sampling is started. For
some time after the start, the flow controllers are checked to confirm that sampling is taking placeat the set flow rate. If field blanks are being collected, the container with the cartridges for the fieldblanks is closed when sampling starts.
‘23’ Once sampling has started, the detailed status of the survey should be recorded. To facilitate
later reference, a record form should be prepared in advance and the information should be recordedin this format every time.
The following information should be recorded: the date and time that sampling started, the date andtime that sampling ended, the location of the survey, the person carried out the survey, the samplingflow rate, and the total sampling amount.
The information mentioned now is mandatory. The weather conditions on the surveying day are also
important information. The temperature and atmospheric pressure should also be recorded if
available. The gold cartridges and pumps are marked with unique ID numbers, which should berecorded at the time of the survey to track the status of the survey. It is also recommended that the83

record form includes a column for recording any special circumstances noticed during the survey.
Such notes should be taken on site, unless prevented by weather conditions or other circumstances.
‘24’ This slide discusses inspections during sampling. As atmospheric mercury surveys take a longtime and the investigator is usually not present at the site most of the time, it is useful to check theoperating conditions during the sampling period if circumstances permit. It is recommended thatthe sampling site is revisited during the sampling period to check items including if the sample
collection is being carried out correctly, if any problems such as stands falling over or tubes
disconnecting has occurred, and if the sampling flow rate is correct. It is useful to have the space
to note the check results in the record form.
‘25’ When the sampling time is over and the required amount of air has been collected, the sampling
equipment is retrieved. Surveys are typically carried out over a 24-hour period. Firstly, the equipment
is examined to ensure that the survey has been carried out properly. Next, the pump is stopped, andthe final sampling volume is recorded. If field blanks are being collected, the case should then be
opened. The dismantling operation should be performed using the following procedure. Gloves
should always be worn during this process, as was done during installation. The tubing and soda
lime trap are removed from the gold cartridges and placed in the case. The case of the field blankcartridges is closed when the samples cartridges are stored in the container. Then, other devices
such as stands, shelters, and sheets, are collected. When the cartridges are sent to the laboratory
for analysis, high temperature and strong light should be avoided during transportation.
‘26’ Duplicate sampling is used to confirm the stability of the survey. It is recommended that
duplicate sampling is carried out at regular survey intervals such as one duplicate for every 10
sampling operations. The procedure is simply to deploy two or more gold cartridges side by side. If
each of the sampled duplicates shows a similar concentration of mercury, then the influence of thesurvey equipment on the result is not significant.

Section 4: Atmospheric surveys in special situation‘27’ Atmospheric mercury survey and monitoring is not limited to the general environment. There
are situations where mercury survey or monitoring is required for other purposes. In many cases,
the manual active sampling method is useful. This section provides examples of such situations.
‘28’ This slide shows examples of survey or monitoring situations in non-general environments.
Some precautions for dealing with issues in special situations for atmospheric mercury survey andmonitoring are explained. When a high atmospheric mercury concentration is expected, the survey
should be conducted with due concern for protecting the workers and nearby residents. Such special

84situations may occur in various scenarios. Firstly, compared to the general environment, higher
mercury concentrations may be detected in the surroundings of mercury-using industrial processes
or mercury-emitting facilities. Secondly, high mercury concentrations may be detected in working
environments where mercury is used, such as artisanal and small-scale gold mining sites. High
atmospheric mercury concentrations may also be detected at waste dumping site where the illegal
or improper dumping of mercury-added products is found. Atmospheric mercury should also be
surveyed in the event of an accident involving mercury or mercury products although continuous
monitoring may not be necessary. For example, an accidental leakage of metallic mercury, or a fire
at a facility using mercury requires a quick response to assess the impact on the residents of thesurrounding area. In these situations, especially where mercury or mercury products are present, theatmospheric mercury concentration may be of the order of thousands of times higher than that of
the general environment.
‘29’ Besides general environmental monitoring, temporary survey may be conducted rather thanperiodic monitoring. The manual active sampling method has advantages for temporary surveys as
the sampling equipment is small and easy to carry. Set-up can usually be completed in one hour andonly requires a small space. Additionally, the battery-run pumps require no external power supply. If
the objective of the survey is to obtain the mean concentration level, the required sampling time may
not be long. Normally, atmospheric samples are collected for 24 hours, but the sampling time may
be shortened to one hour if the concentration is very high and a highly sensitive instrument, such asa cold vapour atomic fluorescence spectrometer, is used for mercury detection. However, someprecautions should be kept in mind when using this manual sampling method in such situations,
including the adverse effect of high mercury concentrations, and the presence of interfering
substances during analysis.
‘30’ In cases of gold mining workplaces using mercury and accidental spill or leakage sites, theatmospheric mercury concentration may be especially high, of the order of thousands of times
higher than that of the general environment. Since analytical instruments have upper limits, mercury
samples with high concentrations cannot be measured. Additionally, samples with high mercury
concentrations, that exceed the maximum value of the calibration curve should not be analysed.
‘31’ Some precautions and measures should be taken for surveys in environments with highatmospheric mercury concentrations. Firstly, the upper limit of the analytical instrument should be
confirmed. The sample volume is determined based on the expected concentration and the
instrumental upper limit. The sample volume should be smaller than that of the general environment;
thus, reducing the flow rate is a good way to reduce the sample volume. The degree of reduction
depends on the performance of the pump and flow controller. According to the Japanese manual,85

the flow rate should be more than 0.1 litres per minute because the flow rate of many types of pumps
become unstable below that level. Shortening the sampling time is another way to reduce thesampling volume. If using this option, the daily average cannot be obtained. This precaution should
be kept in mind for surveys where diurnal variation is large, such as in workplaces. Even when the
mercury amount in the sample is within the measurement range of the instrument, it cannot beanalysed if the value is outside the range of the calibration curve. Thus, a standard at a higher
concentration should also be measured to create the calibration curve if a high concentration is
expected. It is also important to note that the atmospheric sample cannot be diluted after sampling.
This is a major difference from other media such as water, soil, and biota, where samples can beanalysed again with smaller sample volumes using the remaining sample. Atmospheric samples
should be measured all at once using the entire sampling volume. Therefore, if the mercury
concentration in the sample exceeds the upper limit of the instrument, it cannot be analysed. In suchcases, the sample should be collected again with a smaller sampling volume. If the mercury
concentration level of the survey area is unknown, multiple samples with different sampling volumes
should be collected.
‘32’ Interfering substances for instrumental measurements sometimes exist in large quantities,
especially in factories or workplaces. Aerosols, including smoke, restrict the performance of
mercury collection, causing damage to the cartridges. The effect of aerosols is negligible in thegeneral environment, but a filter may be required in locations such as fields with open burning, wherehigh aerosol levels are present. Some chemical substances may also affect the instrumental
measurement data. Examples include halogenated gases such as chlorine and hydrochloride gas,
nitrogen oxide and sulphur oxide, and gaseous organic compounds. The measurement data canalso be affected by very high humidity and, in very rare cases, a high concentration of ozone. In thegeneral environment, halogenated gases, NOx, SOx and moisture can be removed by the soda lime
trap, and most other substances pass through the gold cartridge. However, in environments withespecially high concentrations, such interfering substances may remain on the gold cartridge andaffect the analysis data.
‘33’ There are some measures that can be taken against high amounts of interfering substances. To
remove a high amount of aerosol effectively, a filter can be attached in front of the cartridge. To
remove gaseous interfering substances, such as halogenated gases, NOx, and SOx, a larger soda
lime trap may be sufficient if the amounts of these substances are not extremely high. If theamounts are much higher, a gas scrubber is effective. When a gas scrubber is used, it should be
attached in front of the soda lime trap as it generates water mist. If the electrical power supply isaccessible, a heater can be attached to the gold cartridge to maintain the temperature in the range

86

from 100 to 150 degrees C. Although this is a relatively complex method that requires a heater andtemperature controllers, heating the cartridge is very effective for removing interfering substances.

Part II: Measurement, data processing and QA/QC‘34’ This part describes the analysis of the mercury adsorbed by gold cartridges, data processing,and quality control.

Section 1: Measurement of gold amalgamation cartridge‘35’ This section outlines the operation of a thermal desorption atomic absorption
spectrophotometer, which is the analytical instrument used for atmospheric samples.
‘36’ This slide shows a conceptual diagram of the instrument used for analysing gold cartridges.
Gold cartridges selectively adsorb mercury in the atmosphere, allowing many interfering substances
to pass through. However, some interfering substances are adsorbed by the cartridge, which may
affect the analysis. To prevent adverse effects from interfering substances, this instrument applies
the double amalgamation method, which uses two gold cartridges. A cartridge that collects
atmospheric mercury is installed, as shown on the left side of the drawing. The device is also
equipped with another cartridge, through which the collected mercury is introduced into the atomic
absorption spectrophotometer. The carrier gas used to deliver mercury must not contain mercury.
This instrument uses additional gold cartridge as a mercury scrubber to obtain mercury-free air.
Thus, mercury-free air can be supplied to the atomic absorption spectrophotometer in a very simple
and inexpensive way.
‘37’ This slide explains the flow of analysis for mercury collected in a gold cartridge. Firstly, air
passes through the system from the first cartridge, which contains mercury collected in theatmosphere, and then the second cartridge, which is connected to the analytical instrument. Next,
the first cartridge containing sampled mercury is heated to purge the mercury. When the cartridge
is heated, the collected mercury flows to the second cartridge and is adsorbed. However, most of
the interfering substances adsorbed in the first cartridge pass through the second cartridge. This
process leaves only mercury in the second cartridge and removes most of the interfering
substances. Finally, the second cartridge is heated, and mercury is introduced into the atomic
absorption spectrophotometer for analysis. This device consumes almost no reagents or gases.

87Section 2: CVAAS measurement‘38’ In this section, the instrumental analysis is described. The key points for sample analysis as
well as the analyses required for quality assurance, QA, and quality control, QC are discussed. The
operation Details differ for each analytical instrument and thus will not be covered here.
‘39’ This video shows the analysis of gold cartridges with an atomic absorption spectrophotometer.
In many instruments of this type, a cartridge that collects air must be installed at a particular port inaddition to another cartridge that act as a mercury scrubber. Once the instrument is switched on,
the double amalgamation process runs automatically, and mercury analysis is performed. In
addition to the cartridge containing the collected sample, a blank cartridge that does not containmercury or standards for calculating the mercury concentration must also be analysed. If there aremany samples to analyse, it is necessary to measure the checking standards every 10 samples tocheck the sensitivity of the instrument. For this, a standard with a moderate concentration, that is, astandard from the middle of the calibration curve, is used.
‘40’ The preparation of the standard for atmospheric mercury analysis is explained here. Since theatomic absorption spectrophotometer relies on comparative analysis, it is necessary to analyse amercury standard to determine the absolute mercury concentration using this instrument. A
commonly used method is to collect a certain amount of saturated mercury vapour and introduce it
into the analytical instrument. This slide shows a conceptual diagram of such a mercury standard
gas generator. Metallic mercury is contained in a closed chamber, which is saturated with mercury
vapour. The temperature in the chamber is measured with a thermometer, and then the mercury
concentration in the chamber can be calculated. When a certain amount of air in this chamber iscollected with a gas tight syringe, the amount of mercury collected can be calculated from thevolume of air collected and the saturated mercury concentration. Then, the saturated mercury
vapour is injected into the instrument to analyse the known amount of mercury. Mercury gas
generators that combine such a closed chamber and a thermometer are commercially available,
and by using these devices, it is possible to prepare a mercury standard for creating a calibration
curve.
‘41’ This slide describes the procedure for introducing mercury vapour into the instrument. All thatis required is a mercury gas generator, a gas tight syringe, and an atomic absorption
spectrophotometer. Additionally, a comparison table between the temperature and saturated
mercury concentration should be prepared to determine the gas level in the chamber when drawing
it into the syringe. Such comparison tables are available on several websites. Firstly, the temperatureinside the closed chamber is confirmed and recorded. Then, the saturated mercury concentration to
be drawn from the chamber is recorded by using the comparison table. After that, the gas-tight88

syringe is inserted into the injection port of the mercury gas generator and a certain amount of
mercury gas is drawn. Finally, the syringe is inserted into the injection port of the analytical
instrument and the mercury gas is introduced. The amount of mercury is measured directly andrecorded as standard data for the sample analysis.
‘42’ To develop a calibration curve, standard analysis is conducted at multiple concentrations byinjecting different amounts of mercury gas. A calibration curve should include four or moreconcentration points, which means five or more samples should be used, including zero blanks. It
is important to note that the collected atmospheric mercury sample can be analysed only once. If
the mercury concentration is higher than expected and exceeds the range of the calibration curve,
there is no other way to obtain data than collecting the sample again in the field. Therefore, it isrecommended that the calibration curve range is set to a slightly higher level than the expectedconcentration and that the number of calibration curve points is increased, if necessary.
‘43’ There is an alternative methodology that does not use saturated mercury vapour from astandard gas generator. An inorganic mercury standard solution can be reduced to produce gaseous
mercury. This slide shows a conceptual diagram of a device for generating mercury gas by reduction
and vaporization. Firstly, a mercury standard solution with a mercury concentration corresponding
to the calibration curve is placed in a sealable glass container such as a stoppered flask. Then, thesystem is assembled with a gold cartridge to remove mercury from the carrier air, a soda lime trap,a gold cartridge to adsorb mercury from the standard solution, and a pump. After assembly, a tin
chloride solution is introduced into the flask. Then, the pump is turned on to let air flow through thesystem. Mercury in the solution is reduced and purged into the air, which is then sucked by the pump,and gaseous mercury is adsorbed by the gold cartridge. By repeating this operation several times, a
set of gold cartridges with different concentrations is prepared, which provides the necessary
concentration steps to create a calibration curve. Standard data is then obtained by analysing allthese gold cartridges with an atomic absorption spectrophotometer.

Section 3: Data processing and QA/QC‘44’ After analysing the samples, the mercury concentrations of the samples are calculated basedon the sample data and standard data. This section describes data processing and items used for
QA/QC.
‘45’ Once the analysis data is available, the concentrations of the samples are calculated. This slide
shows the formula for converting the analysis data from the atomic absorption spectrophotometer
into the atmospheric concentration of a sample. A calibration curve is created from the standard

89

data to calculate the amount of mercury in a collected samples. The concentration is calculated by
dividing the amount of mercury obtained by the collected volume. As the concentration should bepresented in standard conditions, it should be converted using the temperature and barometricpressure at the time of sampling, unless a mass flow controller was used for sampling. The standard
conditions usually refer to zero °C and one atm, but monitoring results in Japan are converted to
20 °C and one atm.
‘46’ When analysing mercury, the operation blanks and field blanks, if collected, should also be
analysed. Testing an operation blank is rather simple, as a gold cartridge that has been stored andhas not been used for sampled or absorbing a standard gas is analysed. Normally, no noticeableblank value is detected, as long as the gold cartridge is stored properly. It is important to reiteratethat the collected air samples can be analysed only once. Therefore, the analysis of the operation
blank must be performed before analysing the collected samples. If a significant value is detectedin the operation blank, the causes should be investigated and measures for resolving them should
be taken before analysing the collected samples.
‘47’ It is recommended that a field blank, or travel blank, is performed approximately once in every
10 sampling operations. It is also recommended that three or more gold cartridges are used, insteadof one, when investigating the field blank. The field blank usually does not show a high value innormal surveys, but the level can be elevated on some situations, such as surveys of mercury-using
facilities, due to operational reasons.
‘48’ Even if the collected samples are exposed to a high concentration of mercury during the survey
or transportation, the value of the field blank can be subtracted from the results by assuming that
all cartridges have adsorbed the same amount of mercury. This judgment cannot be made with asingle field blank. The effect on all collected samples can be estimated from the variation in the fieldblank value if multiple field blank samples are collected. When a large value is found, a field blankinvestigation with more than three samples will enable the contamination to be quantified by
calculating the standard deviation. If the standard deviation of the field blank samples is smaller
than the detection limit, the samples are considered uniformly contaminated, and the average valueof the field blank samples can be subtracted from the analysed values of the collected sample.
‘49’ This slide describes duplicate sampling. To ensure the stability of the survey, it is recommended
that duplicate sampling is performed at least once in every 10 survey operations. Two or more
cartridges are used simultaneously for sample collection and the analytical results are compared.
The values should be within 30 % of each other, but the difference is usually much smaller.
’50’ The limit of detection, LOD, and limit of quantification, LOQ, of the method should be confirmedprior to the survey. The LOD and LOQ of the method are obtained from the standard deviation for90

repeated analyses of low-concentration standard gas. Five or more standard gas cartridges, whose
concentration is usually the minimum point of the calibration curve, are prepared and analysed. The
LOD and LOQ are estimated from the standard deviation of the obtained results. The LOD is threetimes the standard deviation, and the LOQ is 10 times the standard deviation. These limits aredefined by the amount of mercury detected, so the limits at actual concentrations will varydepending on the collected sample volume. For 24-hour sampling, these limits are significantly
lower than the background atmospheric mercury levels, which has little effect on the survey results.
This effect, however, must be taken into consideration when sampling is only performed for a shortperiod of time, such as during indoor air surveys.
‘51’ It is important to mention that the survey data must be obtained in a usable manner. The
obtained data should be compiled with ancillary information such as the date and time of the survey,
the location of the survey, and the weather conditions at that time, to improve the usefulness.
Electronic files with related data recorded by location, year, etc. are useful. It is more effective if a
database system is created.

Section 4: Maintenance and calibration methods‘52’ In this section, maintenance and calibration methods for the QC of two pieces of equipment are
explained.
‘53’ This slide explains the method for confirming the recovery rate of a gold cartridge. A gold
amalgamation cartridge can be used repeatedly for atmospheric sample collection. However, thecartridge may be damaged and the mercury recovery rate may decrease if sampling is conductedunder abnormal conditions where a large amount of aerosol is present. When such damage occurs
to the gold amalgamation cartridge, signs are often found, such as lower concentrations thannormal monitoring results or inconsistencies between duplicate samples. In these cases, therecovery rate of the cartridges should be confirmed.
The video shows the confirmation procedure for the recovery rate of a cartridge. Firstly, the cartridge
is connected to an air pump. The pump used for sampling is suitable for the purpose. After the
preparation of the cartridge and pump, mercury standard gas is drawn from the standard gas
generator. The gas should be drawn from the same standard gas generator as used to create thecalibration curve. Once the mercury standard gas is drawn from the generator, the pump is turned
on. As soon as the pump flow rate stabilizes, the mercury gas is injected into the cartridge.
Immediately after injection, another gold cartridge is connected to the injected cartridge to remove91

mercury from the inflow air. The mercury-free air is fed into the cartridge for two minutes to allow
the injected mercury to be adsorbed by the gold trap.
‘54’ After aspiration for two minutes, the cartridge is collected and measured by CVAAS. The
standards for creating the calibration curve are also measured. The recovery rate is calculated fromthe ratio of mercury added to the cartridge and the analysed mercury amount. If the calculated
recovery rate is low, the cartridge requires further cleaning.
‘55’ If the recovery rate of the cartridge is low, it should be cleaned. This video shows the cleaning
procedure using alcohol. For cleaning, methanol or ethanol and a clean cotton swab are used. Firstly,
the exterior of the surface of the tube is wiped. Next, the interior is wiped with a cotton swab dipped
in alcohol. After wiping both the interior and exterior of the tube, the interior is wiped using a new
dry cotton swab to remove the remaining alcohol in the tube. The cleaned cartridge is then left atroom temperature until completely dry.
‘56’ This slide shows another procedure for cleaning the damaged cartridge by heating in an electric
furnace. A cartridge made of quartz will be damaged if heated in the presence of sodium or calcium.
Thus, it should be washed well prior to heating. After washing the cartridge, it is placed on a dishthat can endure strong heat, such as a large evaporating dish, which is then placed in an electric
furnace and heated at 800 °C for 30 minutes. After leaving to cool to room temperature, the cartridge
is collected and stored in a case. There is no guarantee that the cartridge is in good condition after
this procedure; thus, the recovery rate should be reconfirmed.
‘57’ The atmospheric mercury concentration is calculated from the sample volume, so the flow
meter used in sampling should be accurate. To maintain an accurate flow rate, it is recommended
that periodic calibration is conducted by using a standard flow meter. The video shows thecalibration procedure using a standard flow meter. Firstly, the flow meter to be calibrated isconnected to a standard flow meter and a pump. The flow meter in this video is built into the pump
as a flow controller. To stabilize the air flow, a buffer tank is connected between the flow meter andpump. To perform calibration under the same conditions as during actual sampling, a gold cartridgeand soda lime trap are connected in front of the flow meter. After set-up, air is aspirated through theassembled gold cartridge, flow meter, buffer tank, and pump at the same flow rate as during sample
collection. The flow meter is adjusted to match the flow rate indicated on the standard flow meter.
‘58’ After adjustment, the actual calibrated flow rate and its uncertainty should be confirmed. Under
the same conditions, the flow rate indicated on the standard flow meter is collected multiple times
at the same interval, for example, one minute. After recording the flow rates, the average flow rateis calculated as the calibration value of the flow meter. Additionally, the standard deviation is
calculated as the uncertainty of the flow meter.

925.4 Lecture 3: Solid sample (soil,
sediment, and biota) survey andanalysis‘0’ This lecture mainly explains the sampling and analysis of solid samples, such as soil, sediment,
and biota.

Section 1: Key characteristics of soil and sediment‘1’ Firstly, the characteristics of soil and sediment samples, and the sampling procedures are
explained.
‘2’ Importantly, soil and sediment are media that comes into direct contact with animals and plants.
They have a significant impact on local agricultural production and food chains. Additionally, they
are often directly affected by high levels of pollution including the release of waste mercury. Highly
contaminated areas often appear in very limited extents; thus, great care should be taken whensurveying contaminated areas. In addition, mercury in soil and sediment undergoes very complex
transport and reaction processes, such as oxidation, reduction, methylation and demethylation,
deposition and re-release into the atmosphere. Therefore, deliberate assessment is required tounderstand mercury behaviours in areas that include soil and sediment.
‘3’ Solid samples are relatively easy to collect, transport, and store as compared to environmental
water. Nevertheless, special care needs to be taken when transporting and storing samples
containing mercury, as it may volatize over time unless it is in a stable form such as mercury
sulphide. Soil and sediment are the media surveyed for global environmental studies and when local
impact from mercury-using facilities is expected. Soil and sediment near mercury-using facilities
may be affected by the release or leakage of mercury. In such situations, mercury concentrations
can vary significantly within a very small area. For locations where direct mercury release is
expected, the survey samples should be collected within the smallest extent possible. Riversedimentation may be affected locally by the flow of the river, but it is not possible to know theoverall sedimentation status of the entire river from one sediment sample. Thus, it is necessary tocollect samples from multiple locations.

93Section 2: Soil sample collection‘4’ This section introduces composite sampling method using five soil core samples‘5’ The soil sampling method should be selected considering the purpose of the survey, the conditionof the survey site, and the issues to be evaluated such as the effect of mercury deposition in the
background environment or the effect of leakage from a facility. Sometimes stratified deep coresamples may be required or just shovelling soils may be sufficient. Five-point soil sampling is amethod for surveying a relatively wide area with a relatively small number of samples. This method
is suitable at locations where there is no directly released contamination or where the contaminationfrom the polluting facility is sufficiently distant, so that little localised contamination is expected
within the survey area. This method involves collecting samples from five adjacent points, which arethen mixed in equal amounts to make one analytical sample. This method gives an assessment
result for a wide area of soil environments at once.
‘6’ To conduct five-point sampling, the centre of the survey point is determined. Soil samples arecollected at the centre and from four locations at equal distances to the north, south, east, and west.
The distance between the points depends on the size of the survey area, with a distance of five to
10 meters often being chosen. Although it is better to maintain the same distance in all directions,
it may be adjusted to some extent if some obstruction exists. The samples are cored from these
five points.
‘7’ The image shows the core sampler used for soil sampling. This core sampler is driven into thesoil from the surface to collect samples. The surface soil can also be collected with a shovel orother tools, but a core sampler is recommended because it collects the same volume of soil at each
depth. This is especially relevant, as the mercury levels in soil could differ at different depths. Gloves
should always be worn when collecting samples and handling the collected samples. Disposable
gloves are convenient for this purpose. Firstly, the extraction handle is attached to the sampler,which is then set on the sampling location and driven into the ground. Once the sampler is inserted
to a certain depth, it is extracted with the handle. Sometimes the sampler may not reach the depth
due to a hard object, such as a rock, underneath. To avoid the core sampler being damaged, thesampling location can be slightly adjusted to avoid such hard ground.
‘8’ Together with sampling, information such as the sampling location, sampling date and time, andthe operator collecting the samples should be recorded. Additionally, features of the collected
samples that might affect the mercury contamination status should be recorded, if identified. The
colour of the collected soil should be referenced to a standard soil colour book and recorded, which
will be useful for later analysis. Although soil colour and mercury concentration do not have a direct
relationship, the soil colour can be used to group soil samples with the same characteristics. It

94

serves as useful information for estimating the extent of contamination, if identified. When samplingis completed, the collected samples in the samplers are placed in plastic bags and brought back to
the laboratory. Short transportation of samples can be done at normal temperatures. If
transportation takes a long time or the samples are stored for some time before analysis, thesamples should be kept at a low temperature to avoid the volatilization on mercury. At the laboratory,
the five collected samples are mixed in equal weights, not the full samples. Thorough mixing isnecessary to achieve homogenization for analysis.

Section 3: Sediment sample collection‘9’ This section explains the collection of sediment samples.
‘10’ Normally, sediment samples cannot be collected with a shovel, instead special samplers areused for this purpose. The video shows a sediment sampler called an Ekman-Birge mud collector.
This instrument is thrown into water with the collection flaps open. When the collector reaches thebottom, a weight is dropped as a messenger to close the flaps. Then, the collector holds thesediment when recovered. The sediment sampler can conveniently collect sediment samples by
being thrown into water from ships or bridges. As there is another sediment sampling method, coresampling differs from this grab-type collection method. In core sampling, a columnar sample inobtained to analyse the vertical profile of the sediment layers.
‘11’ Firstly, the mud collector is lowered from a ship or bridge above the sampling point to the bottomof the water body with the sampling port facing downward. Once the mud collector hits the bottom,
the tension in the hanging rope decreases. The rope is pulled up a little to take up the slack, and thenthe messenger is plummeted along the rope. After the messenger reaches the mud collector, thecollector is slowly pulled up. If sediment is not held in the mud collector due to factors such as thelanding angle or malfunction of the messenger, the same process is repeated to collect a sediment
sample. Since the properties of sediment usually vary significantly at different sampling points, atleast three samples are collected and mixed to make a representative sample of the survey site.
‘12’ Collected sediment is spread over a vat to observe the colour, odour, and other features. The
colour should be referenced to a standard soil colour book and recorded as a Munsell number, as isdone for soil. The collected sediment is thoroughly mixed and then placed in a sealed container totake back to the laboratory. As is done for soil, the sediment must be kept in cold conditions when
the transport time is long, or the samples are stored until analysis. Information such as the date andtime of sample collection, the sampling location, and the operator collecting the sample should be95

recorded on site. It is also recommended that the type of mud collector used for sampling, and theproperties of the sediment are recorded.

Section 4: Biota sample‘13’ This section briefly addresses the collection of biota samples.
‘14’ The collection of biota samples varies significantly depending on the purpose of the survey, thespecies, the habitat of such species, etc., and thus is not presented here. The important point is to
identify the target species to be collected without ambiguity. Even if the species is identified, thevalue of the analytical results will be minimal without supplementary information such as the bodylength and weight of each sample. In particular, the body length and weight of fish have a strong
correlation with mercury concentration. Other information such as the date, time, and place ofcollection is also essential. The sex and age of the biota samples are also valuable, if available. For
biota samples such as fish, muscle tissue is taken, homogenized, and analysed. The muscular partof the sample is cut with a knife and homogenized with the knife, or a kitchen blender.

Section 5: Total mercury analysis‘15’ The analysis of total mercury in the laboratory is described in this section. Among several
methods for analysing total mercury, cold vapour atomic absorption spectrometry, CVAAS, is
explained. In this method, samples are digested with acid, and then mercury in the solution is purgedout by reduction aeration.
‘16’ This diagram shows the operational flow of the acid digestion-reduction aeration CVAAS
analysis method. Firstly, a sample is decomposed with nitric acid, perchloric acid, and sulphuric acidin an open vessel. After digestion, mercury in the sample solution exists in a divalent oxidized form,
which is highly soluble in water. Once mercury is reduced with tin chloride to elemental mercury,which has low water solubility, it is vaporized and introduced into the CVAAS for measurement.
‘17’ The reagents used in this method are shown here. Concentrated nitric acid and perchloric acidare mixed in equal volumes to prepare a one-to-one solution. Concentrated sulphuric acid without amercury blank, which is available commercially, is used. Sodium hydroxide solution is prepared bydissolving the reagent in a small amount of water, which generates dissolution heat. The solution
can be prepared more easily if water is added little by little to minimise the heat generated insteadof adding the water all at once.

96‘18’ The preparation of a methylmercury solution as a standard solution is described here. Prior to
the analysis, a standard solution is prepared for creating a calibration curve. It is also possible todilute and use a commercially available standard solution. However, please be mindful that thegeneral mercury standard solution is in an inorganic form under acidic conditions with nitric acid,
which is relatively unstable once diluted. L-cysteine should, therefore, be added to the diluting waterof an inorganic mercury standard solution to prevent the change in concentration. The standard
solutions with L-cysteine is stable for at least six months if it is kept in dark and cool condition. A
methylmercury standard solution is recommended for calibration curve, if possible, even for total
mercury analysis. A very stable standard stock solution can be prepared by accurately weighing
methylmercury powder and dissolving it in toluene. The prepared methylmercury standard stock
solution is kept in an airtight bottle and can be used for a long period of time if stored in the
refrigerator.
‘19’ The methylmercury standard stock solution is a toluene solution, which cannot be used forstandard solution measurement. Therefore, methylmercury is extracted with L-cysteine to prepare
an aqueous solution of a methylmercury-cysteine complex. Precise amounts of L-cysteine aqueous
solution and methylmercury toluene solution are mixed to extract methylmercury into the aqueous
phase, which is then centrifuged to separate the toluene. Finally, the remaining toluene is removed
from the aqueous solution to make a standard solution for analysis. This methylmercury-cysteinecomplex aqueous solution is not as stable as the toluene stock solution, so that it should bediscarded and re-prepared after approximately one month.
‘20’ The actual analysis operation is explained here. Firstly, the sample is weighed and placed in acontainer for digestion. Every morning prior to sampling, the condition of the analytical balance ischecked with weights or other means. The amount of sample may vary depending on the estimatedmercury concentration in the sample. The maximum amount is approximately 0.5 gram for thismethod. The digestion container can be any receptacle that can resist heating with a strong acid,and that does not elute or adsorb mercury. In this video, volumetric flasks are used for digestion, as
the shape is suitable for this purpose. To check the quality of the analysis, duplicate samples areadded every 10 samples. If available, a certified reference material, which has the same or similar
properties as the samples being analysed with a certified mercury concentration, can also be
included to examine the validity of the analysis results.
‘21’ The standard solution of methylmercury cannot be directly analysed by CVAAS. It must undergo
the same sample digestion process. The mercury solution is added to the digestion containers sothat the amounts of mercury are appropriate for creating a calibration curve. A container without
added mercury is also prepared to serve as an operation blank.

97

‘22’ The samples are placed in the digestion containers and decomposed with acid. A zeolite boilingstone is placed in each container with the sample, and then one mL of deionized water is added.
After that, the digestion acid is added to the container. Firstly two mL of a one-to-one mixture ofnitric acid and perchloric acid is added, followed by five mL of sulphuric acid. When there are many
samples to be analysed, the dispensers shown in the video might be convenient. The samples withacid are heated and digested at 200 to 230 °C. If a hot plate is used as is in this video, the surface
temperature may be different at different areas. In particular, when placing many samples on a hot
plate, some areas may not reach a sufficiently high temperature. Therefore, it is recommended thatthe surface temperature is measured during operation to confirm that the temperature is highenough for digestion. After digesting for 30 minutes, the heating is stopped and the samples are left
to cool to room temperature. Once the sample is sufficiently cool, the volume is adjusted to 50 mL,
and this solution is used for analysis. The same process is also applied for the standard solutions
for the calibration curve.
‘23’ As soon as digestion is conducted, the operation details should be recorded. The necessary
information for this pre-treatment operation includes date and time, operator, sample amount,duration of digestion, and final preparation volume. It is beneficial if the record form is prepared inadvance. A remark box in the form can be conveniently used to add any notes about special
situations that occur during the operation.

Section 6: Measurements, data processing, and QA/QC‘24’ Analysis, data processing, and QA/QC of the samples after acid digestion by reduction aeration
CVAAS are explained in this section.
‘25’ After acid digestion, the samples are analysed with reduction aeration CVAAS. Prior to themeasurement operation, the reagents must be prepared. Tin chloride is usually used to reduce andvaporize mercury in the sample solutions. To prepare the tin chloride solution, tin chloride isdissolved in concentrated hydrochloric acid and then diluted with deionized water. A trace amountof mercury may be present in the tin chloride solution at a level that would affect the operation blank.
Most mercury can be removed by purging with nitrogen gas for approximately 30 minutes.
‘26’ Once the digestion process is complete and the tin chloride solution is prepared, the samples
and standard solutions are analysed with reduction aeration CVAAS. The detailed operation may
differ in different instruments. The explanation here is for a process with a relatively simple
instrument. Prior to analysis, the tin chloride solution is placed at the specified position in the
instrument. Firstly, a sample is injected into the reaction vessel. Then, the lid is closed and the tin

98chloride solution is added to the vessel. The sample and tin chloride react in a closed system for acertain period, approximately 30 seconds, to reduce the oxidized mercury into elemental mercury.
The reduced mercury is vaporized and circulates in the air of the reaction vessel. Once the reaction
time has lapsed, the valve of the reaction vessel opens automatically, and mercury is introduced into
the atomic absorption spectrophotometer. As the mercury in well-mixed air is introduced all at once,the signal appears as a sharp peak. The peak heights are measured and compared to obtainaccurate data. After the analysis, mercury in the sample flows out of the instrument with the exhaustgas, which is trapped with an absorbing solution such as potassium permanganate.
‘27’ The operation blank is analysed first followed by the standard solutions for the calibration curve.
Finally, the collected samples are analysed, including duplicates if duplicating sampling is
performed. When analysing the collected samples, it is recommended that a standard sample witha moderate concentration is inserted every 10 samples to confirm that the sensitivity has not drifted.
This standard solution for the calibration curve is also pre-treated by acid digestion; therefore, asufficient quantity of the standard solution should be prepared in advance, depending on the numberof samples to be analysed. If the standard solution runs out during the analysis, the operation must
be interrupted. Thus, the amount of standard solution required for the entire operation should be
estimated in advance.
‘28’ Once the analysis is complete, the mercury concentrations are calculated. Firstly, the calibration
curve is created from the results of the standard solutions. Then, the total mercury concentrationsin the samples are calculated. As the standard solutions used in this method were pre-treated byacid digestion, zero in the standard solution for the calibration curve is equivalent to the operation
blank.
‘29’ The important factors for QC of the analysis are explained here. If an elevated operation blankis found after analysing the collected samples, the analysed results are not valid. Furthermore, thisalso results in the loss of valuable samples collected in the field. Thus, the operation blank should
always be checked before analysis to confirm that satisfactory performance is possible. When anelevated operation blank is found, possible causes should be investigated, including the reagents,
equipment, or other items used for the analysis operation. Once the cause is identified, appropriate
measures should be taken, which may include but are not limited to improving the cleaning method
for tools and obtaining reagents without a blank level.
‘30’ Duplicate analysis is performed to determine the reproducibility of the analysis, that is, todetermine if the same result is obtained by analysing the same samples. It is recommended that aduplicate sample is inserted approximately once in every 10 samples. If the amount of collected99

sample is insufficient to conduct multiple analyses, duplicate analysis can also be performed withother samples. For example, reference materials can also be used for this purpose.
‘31’ The reproducibility of the analysis within a day can be evaluated from the duplicate analysis. It
is also effective to analyse the same sample in each batch or on each day to confirm thereproducibility of the analysis on different days. Therefore, it is recommended that the results forreference materials are compared between the processed batches, usually daily. Certified referencematerials, CRMs, which are commercially available, are the reference materials with traceable
certified values given by national or international standards. A CRM can also be used to confirm theaccuracy of the analysis results. Although CRMs are expensive for everyday use, CRM analysis atcertain interval is recommended, if possible.
‘32’ Similar to the operation blank, the limit of detection, LOD, and limit of quantification, LOQ, areimportant factors for proper analysis and must be confirmed prior to analysing the actual samples.
There are several methods for calculating the LOD and LOQ described in different manuals.
Basically, these values are determined by the following two factors: the sensitivity of the instrument,
which is the level that can be detected, and the degree of variation between the analysed values,
which is the reliability of the obtained values. In general, the sensitivity of the instrument is evaluatedbased on the ratio of the signal detected for the sample and the noise of the instrument. The
variability of the analysed values is evaluated using the standard deviation for repeated analysis of
the operation blank and low-concentration samples. LOD and LOQ are the higher limits that fulfil
these conditions.

Section 7: Other methods for total mercury analysis‘33’ A few other methods for measuring mercury in solid samples are introduced in this section.
‘34’ Thermal decomposition CVAAS is another type of mercury analysis instrument. The principle ofthis instrument is rather simple. Mercury is liquid at normal temperatures and vaporized at hightemperatures; thus, the instrument heats the sample to decompose all mercury into a gaseous form,
which is then detected by the instrument. Mercury existing as organic mercury, such as
methylmercury, or oxidised mercury in the sample is mineralised or reduced during the heatingprocess, and eventually sent to the detector in the form of elemental mercury. Although the principle
is simple, the mechanism and temperature control programme are important to decompose andvaporize mercury effectively. The instrument is deliberatively designed for this purpose. The
analytical operation is also simple. The sample to be analysed is placed in a vessel and loaded in
the instrument together with the standard solution. Thermal decomposition CVAAS is a convenient100instrumental method, as it uses very little reagent and no pre-treatment is required. However, despite
the operational simplicity, the QA/QC analysis, including the operation blank, duplicates, andreference materials, is still important.
‘35’ This slide introduces an example application of thermal decomposition CVAAS. An atmosphericpassive sampler made of activated carbon is used as an absorber. Collecting atmospheric mercury
with a passive sampler is simply done by setting the samplers at the site for a certain period. After
sampling, the sampler is analysed in the laboratory. The analysis of the activated carbon in thepassive sampler can be done by acid decomposition-reduction aeration CVAAS. However, activatedcarbon reacts violently during acid decomposition as it is made of organic material, so special
treatment and skilled operation are necessary. Therefore, thermal decomposition CVAAS isadvantageous for the analysis of passive samplers. Nevertheless, a few points must be kept in mind
for analysis by thermal decomposition CVAAS. Activated carbon reacts more violently than normalorganic samples and may flare up in the reaction cell. To suppress this reaction, it is necessary tochange the carrier gas during thermal decomposition from oxygen to air or nitrogen. If sulphur isadded to the activated carbon to enhance mercury adsorption, it interferes with the mercury
analysis. Thus, processes such as adding reagents that mask the released sulphur are also required.
CRMs for passive samplers are not yet available, but the CRM of coal can be used as an alternative
substance with similar properties.
‘36’ This slide briefly explains the screening of samples that may contain very high concentrations.
Mercury-added products, waste containing mercury-added products, waste contaminated withmercury, or survey samples such as contaminated soil at gold mining sites or facilities that use
mercury are very important for understanding the status of mercury pollution. However, as thesesamples contain intentionally added mercury or are directly contaminated with mercury, they often
contain very high concentrations of mercury. For example, in the case of personal care products thatuse mercury as an active ingredient, the mercury content may exceed one percent, which is 10,000
ppm. If a sample containing such an extremely high concentration of mercury is unintentionallyanalysed in the same manner as a normal sample, it will exceed the measurable concentration
range, and thus an analytical result will not be obtained. Furthermore, such high concentrations of
mercury can contaminate entire laboratories, including tools and analytical instruments, which may
require repair and cleaning.
‘37’ Screening to determine the mercury levels in products or waste with unknown concentrations
prior to analysis will prevent improper analysis and contamination of the laboratory environment. An
X-ray fluorescence analyser, XRF, is a useful instrument for screening. XRF is inferior to atomic
absorption spectrophotometers in terms of measurement sensitivity, and the measurement results101are affected by the material and composition of the sample. However, this instrument can measure
the mercury level without pre-treatment in the laboratory. Furthermore, some XRF instruments areportable, so they are suitable for onsite screening. If a certain level of mercury is detected by XRF,
the sample volume can be adjusted to fit the detection level for analysis. If the purpose of theanalysis is to remediate contaminated soil, the soil can be directly removed if the mercury level inthe soil detected by XRF with sufficient accuracy. If mercury is not detected by XRF, it can beassumed that the highest possible concentration is below the detection limit of XRF.

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5.5 Lecture 4: Water sample survey andanalysis‘0’ This lecture explains the collection and analysis of water samples.

Section 1: Key characteristics of water for mercury survey and analysis‘1’ The significance of mercury pollution in aquatic environments and the characteristics of water
samples for survey and analysis are explained.
‘2’ This slide explains the importance of aquatic environment surveys for understanding mercury
pollution. Water is an essential element for all living creatures, and aquatic environments such as
oceans, rivers and lakes are very important for human life and ecosystems. Water is also an
important medium for understanding the dynamics of global mercury pollution. Mercury in an
aquatic environment is transported with the water stream. Ongoing chemical reactions in bodies ofwater, such as mercury methylation, demethylation, oxidation, and reduction are especially complex.
Furthermore, mercury is often taken up from aquatic environments into the ecosystem, where
bioaccumulation and biomagnification through the food chain begins. For this reason, aquatic
environments are important research media from both regional and global environmental
viewpoints.
‘3’ This slide describes the characteristics of water samples for mercury research and analysis.
Firstly, for water samples, it should be noted that the mercury concentrations in background areas
without local contamination are very low in comparison with those of other environmental media.
The concentration varies due to regional and environmental factors, but a background aquatic
environment survey should allow the system to be accurately analysed at a level of approximately
one ng/L. For this purpose, the collected samples need to be concentrated during the analyticalprocedure or very sensitive analytical instruments should be used. Furthermore, the blank values
from the laboratory environment, reagents, etc. become significant when analysing low
concentration samples. Thus, the reduction of the operation blank level is more important than inother media. Another concern for mercury is its instability in water, which is a major difference fromother metallic elements. As a result, mercury loss occurs relatively easily. Other metallic elements
are not usually lost from collected water samples, but mercury may be reduced and vaporised undercertain environmental conditions or penetrated through the surfaces of containers made of certain
materials. Therefore, special attention must be paid to selecting the container type and to stabilizing
mercury after sampling. Water samples are often larger in volume and heavier than samples in othermedia, partly because of the low mercury concentration. In addition, due to the instability of mercury

103and the risk of damage and leakage, the transportation and storage of water samples is often
challenging.

Section 2: Water sample collection‘4’ In this section, the procedure for collecting water samples using a water sampler is explained.
‘5’ When sampling water, a clean pail can be used, for example, for collecting drainage of water tanks
in the facility or surface water in rivers, sea, etc. However, collecting water at a specific depth
requires a specific water sampler. The photo shows a water sampler called a Niskin bottle, which isoften used for this purpose. There are several other types of water samplers for different purposes.
These water samplers are usually lowered into water with open lids, and once the target depth isreached, the lids are shut by a sinker, called a messenger, released by the operator.
‘6’ This slide explains how the Niskin bottle works. This device is actually submerged in water during
operation, but the video is taken in air as the movement under water is not clearly visible. In the
Niskin bottle, any part in contact with the sample water is made of resin, which is suitable forcollecting water samples for surveys of metals such as mercury. As is common for many water
samplers, the Niskin bottle is slowly lowered into a body of water with both the upper and lower lids
open. Once the device reaches the depth for sample collection, a sinker, called a messenger, isplummeted along the wire. With the messenger hits the sampler, the lids shut and the water inside
is trapped. Finally, the sampler is pulled out of the body of water to retrieve the collected water.
‘7’ This slide describes the container materials that can be used for mercury surveys. Unlike manyother metals, mercury can permeate the surfaces of containers made of certain materials. Glassand fluoropolymers are suitable materials to avoid mercury permeation. Although glass is not
usually a suitable material for metal surveys as it may elute the metals of interest, it can be used for
mercury surveys because mercury is not contained in glass. On the contrary, containers made ofpolyethylene or polypropylene are not suitable as mercury permeation is relatively easy. To reducethe blank level elution from the container, it is recommended that the containers are soaked in acidsolution during storage, and then cleaned with deionized water and dried on the day before
sampling. It is important to mention that regardless of the container material, mercury in the water
sample will be reduced and volatilised. Thus, stabilisation to prevent mercury volatilisation is always
needed.
‘8’ The actual operation of water sample collection is explained here. Water samples are usually
collected from a bridge or boat. The sampler is gradually lowered into the water with the top andbottom lids open. After submerging the sampler to the target depth for sampling, the messenger is104

plummeted along the wire. It takes some time for the messenger to hit the sampler. After waiting
for the messenger to hit the sampler, the sampler is pulled up with the wire.
‘9’ Once the sampler is retrieved, the sampling cock on the sampler is opened to transfer the water
into the water container. The remaining water is placed in a beaker or another receptacle to measure
the water temperature and pH. Although the water temperature and pH are not necessary to analyse
mercury concentration, these parameters should be measured as much as possible because they
provide very important information for understanding the condition of the survey site at the time ofsampling. As mercury in water samples is unstable, mercury is effectively stabilised by adding astabilisation reagent, such as hydrochloric acid, immediately after collection. If it is not possible todo this on site, the samples should be brought back to the laboratory as soon as possible forstabilisation. Finally, the collected samples are put in plastic bags and then transported and stored
under cool and dark condition.
‘10’ After sampling, the status of survey is recorded. The recording should be done at the sampling
site, unless prevented by the weather or other conditions. The more time that passes after sampling,
the more difficult accurate recording becomes. The information to be recorded includes the
sampling date and time, operator, name and coordinates of the sampling point, sampling depth,
sampler used, sampled volume, container used, water temperature, and pH. It is convenient toalways use the same format for the on-site recording of the collection status for later reference. As
water and sediment samplings are often carried out at the same location at the same time,developing a format that accommodates information about both water and sediment samples
provide additional convenience.
‘11’ Another water sampling method using a bucket is explained here. A bucket can be used tocollect near-surface water but not water in the middle or bottom layers. There are some tricks tocollecting water using a rope and bucket. If the bucket is slowly lowered from a bridge or boat to thewater, the bucket sits on the water surface and cannot easily scoop water. Instead, water sample
can be easily collected by dropping the bucket upside down, straight onto the water. Care must be
taken not to collect floating objects such as litter or oil when collecting surface water. Such objects
exist only on the very surface of the water; therefore, at sample mixed with these objects may not
represent the actual condition of the surface water at the sampling site. If litter or oil is identified on
the surface of the water, it should be prevented from entering the bucket during water collection. As
with water samplers, processes such as stabilisation and measuring the temperature and pH should
also be performed.

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Section 3: Total mercury analysis for water sample‘12’ This section describes total mercury analysis for water samples applicable for both freshwaterand sea water. The method of extracting and concentrating mercury as a dithizone complex is
introduced here.
‘13’ This diagram outlines the analysis of total mercury in water samples. High-sensitivity measuring
devices such as an atomic fluorescence spectrometer, AFS, are sensitive enough to measure
background-level environmental water samples. When cold vapour atomic absorption spectrometer,
CVAAS, is used for water samples in the general environment, mercury cannot be detected unlessthe sample is concentrated before analysis. Firstly, mercury in soluble and suspended forms is
separated by filtration as the method only applies to dissolved mercury. Suspended matter isanalysed separately as a solid. All mercury in the filtrated water sample is oxidized with potassium
permanganate. Then, potassium permanganate remaining in the solution, which interferes with theprocess, is reduced with hydroxylamine. Mercury in the sample is extracted as a dithizone complex
into a small amount of toluene. After evaporation, the complex is digested with nitric acid, perchloric
acid and sulphuric acid, as is done for solid samples, and then mercury is analysed with reduction
aeration CVAAS.
‘14’ The reagents used in the analysis are shown on this slide.
‘15’ As explained here, 20 normality sulphuric acid is prepared by gradually adding 60 mL ofconcentrated sulphuric acid into 35 mL of deionized water. Since concentrated sulphuric acid is
added to a small amount of water, a significant heat of solution is generated, which may lead toboiling if prepared at room temperature. The solution is cooled in an ice water bath to avoid boiling,and sulphuric acid is added gradually to minimise the generated heat of solution.
‘16’ Sodium hydroxide does not dissolve easily when water is added all at once. It is firstly dissolvedin a small amount of water to generate a heat of solution. Then, the concentration of dissolved
sodium hydroxide is adjusted by adding the remaining water.
‘17’ This slide describes the preparation of a dithizone-toluene solution. Dithizone is weighed anddissolved in toluene. Then, this solution is extracted once with a 0.1 normality sodium hydroxide
solution. As dithizone is a weak organic acid, it moves into the aqueous phase under alkalineconditions. After that, the solution in which dithizone is dissolved is acidified with hydrochloric acid.
Under acidic conditions, dithizone becomes soluble into toluene, which enables its extraction into
toluene again. Dithizone can be purified by applying this process repeatedly. As dithizone is easily
decomposed, it is prepared before each analysis and kept in dark conditions when not in use.

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‘18’ The analysis operation is explained here. Firstly, the water sample is placed in a separatory
funnel. Then, 20 normality sulphuric acid and potassium permanganate solution are added tooxidize the mercury in the sample. The sample is left for five minutes to allow mercury to reactcompletely.
‘19’ After five minutes, the sample is neutralised with the sodium hydroxide solution. Then,hydroxylamine is added to reduce and decompose permanganate. If the purple colour of
permanganate does not disappear, more hydroxylamine should be added, as this indicates that theamount of hydroxylamine is insufficient.
‘20’ After the purple colour of permanganate disappears completely, an EDTA solution is added.
Then, 10 mL of dithizone-toluene solution is precisely measured and added with a whole pipette.
The sample is shaken well for one minute and then, left until toluene and water are separated.
‘21’ Once extraction with dithizone-toluene is complete, and the toluene and water phases are
separated, the toluene phase is transferred from the separatory funnel into a test tube. Water still
exists in the toluene phase despite the extraction process; thus, the sample is centrifuged toseparate water completely. Then, exactly seven mL of the toluene solution is collected using a pipet.
The solution is concentrated with a rotary evaporator to completely remove toluene, as any toluene
remaining in the sample interferes with the subsequent acid digestion treatment. The concentration
process should be continued until the liquid is completely gone.
‘22’ After extracting mercury with dithizone-toluene and removing the toluene completely, thesample is digested with acid by adding one mL of deionized water, two mL of a one-to-one mixtureof nitric acid and perchloric acid, and five mL of sulphuric acid. The acid-added sample is digested
by heating at 200 to 230 °C. If a hot plate is used, the temperature may not be sufficiently high fordigestion. It is recommended that the actual temperature of the hot plate surface is measured toconfirm that it is sufficient for the digestion. After digesting for 30 minutes, heating is stopped andthe samples are left to cool to room temperature. Once the samples have cooled sufficiently, thevolume of each sample is adjusted to 50 mL for analysis.
‘23’ In this analysis method, the standard solutions for preparing the calibration curve are extracted
and digested in the same manner. When placing a sample in the separatory funnel, the same amountof deionized water is added. The numbers of the water samples prepared corresponds to the points
needed for the calibration curve. Then, the standard solution is added to each separatory funnel at
the amount corresponding to the concentration level of the calibration curve. An operation blank,
containing only deionized water without added standard solution, is also prepared. After that, thesame treatment as done for the collected samples is performed to prepare standard solutions forthe calibration curve.

107‘24’ Once the analytical operation has been performed, the details of the operation should berecorded immediately. The necessary information includes the pre-treatment status of the samples,that is, the date and time of treatment, the operator who performed the treatment, the amount ofsample used, the amount of standard solution used, the amount of toluene used for extraction, theduration of digestion, and the final preparation volume. For later reference, it is beneficial if therecord form is prepared in advance. In addition, an entry field for special notes is useful to record
special situations that occur during the operation.
‘25’ Once the extraction and digestion operations are complete, both the samples and standard
solutions are analysed with a reduction aeration atomic absorption spectrophotometer. A sample isplaced in the reaction vessel, whose lid is closed soon after injecting the sample, and then tin
chloride is added. Mercury in the sample solution in the instrument is reduced by tin chloride,
vapourised and introduced into the detector. These operations differ in different types of
instruments, many of which perform this process automatically. Therefore, the details should be
confirmed using the instruction manual of the instrument being used. The analysis is performed in
the following order: operation blank, standard solutions for the calibration curve, and collected
samples. If the number of samples exceeds 10, a standard solution with a moderate concentrationin the calibration curve should be analysed every 10 samples. This step is to confirm that thesensitivity of the instrument is not fluctuating. After analysing the samples, a calibration curve iscreated based on the data obtained for the standard solutions and the concentrations of thesamples are calculated.

Section 4: Quality control - Reducing operation blank level‘26’ In this section, some means for reducing the operation blank values, which is a very importantfactor for quality control of the analysis of low-concentration water samples, are explained.
‘27’ Efforts should always be made so that the operation blank has the lowest value in all analyses,
but this is especially important for analysing total mercury in environmental water as the mercury
concentration is usually very low. If a low concentration sample such as environmental water isanalysed under an analytical condition with a high operation blank, a valid value will not be obtained,
and the collected sample will be lost. To avoid wasting the efforts made for sample collection andanalysis, the operation blanks for the laboratory analysis must be confirmed before analysing thesamples. Even if the operation blank is sufficiently low, efforts to further reduce the operation blankvalue should always be performed to prevent accidental increases and to improve the quality of thedata. Such efforts include: reliably cleaning the sample containers and glassware used for the
analysis and reagent management to prevent the use of old or potentially contaminated reagents.

108‘28’ This slide explains the method for cleaning glassware. Cleaning with a potassium
permanganate solution is effective for reliably removing mercury from glassware used for total
mercury analysis. The glassware used or to be used for analysis is immersed in a potassium
permanganate solution. If possible, it is more effective to perform ultrasonic cleaning while theglassware is immersed in the potassium permanganate solution. After cleaning with the potassium
permanganate solution, the glassware is rinsed with deionized water and dried in a clean
environment.
‘29’ Another method for lowering the operation blank is to treat the tin chloride used in the reducing
aeration atomic absorption spectrophotometer. Commercially available tin chloride contains a trace
amount of mercury, which affects the analytical results. This mercury can be removed relatively
easily by blowing with nitrogen after preparing the solution. The 10 percent tin chloride solution used
for the analysis is prepared by dissolving tin chloride in hydrochloric acid and then diluting with
deionized water to an appropriate concentration. After that, nitrogen gas is blown into the solution
to expel mercury. Blowing for approximately 30 minutes can significantly decrease blank value, but
this process is more effective if done for a longer time.

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5.6 Lecture 5: Human biological sample
analysis‘0’ This lecture explains the analysis of hair, blood, and urine, which are the media related to humanhealth. The analysis of these media is particularly useful for the risk assessment of vulnerable
populations such as children and women of child-bearing age, or high-risk groups with vocational
mercury exposures.

Section 1: Key characteristics of human biological samples‘1’ Mercury is an element with many unique physicochemical properties, and its behaviour in thehuman body differs from that of other organic and inorganic chemical substances. This section
introduces the characteristics of mercury in the human body. These unique characteristics areimportant factors for conducting mercury surveys in the human body.
‘2’ Hair is the most typical monitoring medium for mercury surveys. Hair can take up methylmercury
during growth. The methylmercury level in hair is much higher than that in other parts of the body;therefore, hair is a very good indicator for evaluating the exposure to methylmercury. Since hairsampling is non-invasive, it does not burden the person subject to the survey very much. However,the survey should be very carefully planned, as some people or groups have cultural or customary
intolerance against cutting hair. Because hair itself is a stable medium and most mercury in hair isin the form of methylmercury, samples are relatively easy to transport and store. In addition, as hair
grows, the past exposure information is recorded toward the tip of the hair. Thus, analysing mercury
in hair from the root to the tip can provide information about the historical methylmercury exposureof the individual.
‘3’ This slide describes the characteristics of blood samples. Blood plays an important role in themetabolism of many chemical substances in the human body, including mercury in both organicand inorganic forms. For this reason, blood can be a good indicator of both inorganic mercury andmethylmercury. However, it should be noted that the level of inorganic mercury in the blood of thegeneral population is usually low as their exposure is low. Blood sampling is an invasive means ofsampling, so the risk to the person subject to blood collection is higher than the risk during hair or
urine collection. Therefore, the hygienic conditions for sample collection must be properly managed.
Another important aspect of mercury in blood is that most methylmercury exists in red blood cells
and most inorganic mercury exists in plasma. This feature is particularly important when analysing
mercury in samples other than whole blood.

110‘4’ The characteristics of urine are explained in this slide. Elemental or inorganic mercury taken into
the body by inhalation of mercury vapour is not accumulated in hair but mostly excreted in urine. For
this reason, urine is a very good indicator for exposure to elemental or inorganic mercury. Similar tohair sampling, urine sampling is non-invasive and can be done relatively easily without much healthrisk to the person subject to the survey. Although sample collection is rather easy, urine samples
need particular care when handling after collection. Most mercury in urine is in the form of inorganic
mercury, which is unstable and easily evaporated; therefore, the collected samples should be
promptly frozen or otherwise treated. If on-site stabilisation is not possible, the samples should besent to the laboratory as soon as possible at the lowest possible temperature, and then treated using
an appropriate method, such as freezing. Another important aspect, which is not limited to mercury,is that the concentration of chemical substances in urine significantly varies due to the amount ofwater excreted. The mercury concentration also varies in each excretion, so it is evaluated against
the creatinine concentration, which is stable throughout the day. The concentrations of mercury andcreatinine are analysed separately, and the body burden for the person subject to the survey isevaluated based on these concentrations.

Section 2: Hair sample collection‘5’ In this section, the procedure for collecting hair sample, which is unique to mercury surveys, isexplained.
‘6’ This video shows the actual collection scene for hair samples. Firstly, approximately 20 threadsof hair are grabbed and tied near the root with adhesive tape. The bundle of hair is then cut from theroot with scissors so as not to injure the scalp. The collected hair is put in a container fortransportation to prevent scattering and keep it away from dust. Small envelopes are suitable forthis purpose. Hair sample collection itself is easy, but some care needs to be taken to avoid improper
handling that will spoil the credibility of the data. It should be ensured that the hair is collected fromthe root so that the recent exposure status at the time of collection can be evaluated. Additionally,
the hair should be securely bundled so that the bundle does not fall apart after collection. The bundle
should indicate either root or tip end of the hair. It is recommended that hair is tied at the root end
to confirm the direction of growth.
‘7’ After taking the collected hair back to the laboratory, the sample is cut to the required length forthe purpose of the evaluation. For a person subject to methylmercury exposure, 20 threads of hairwith three cm are sufficient to evaluate the exposure environment over approximately three months.
After cutting the hair to the required length, it is washed with detergent to remove dust on the surface.

111

Then, it is rinsed well with deionized water, dried with acetone, put in a glass container such as apetri dish, and shredded into fine pieces with scissors.

Section 3: Total mercury analysis for human biological sample‘8’ The analysis of total mercury in biological samples can be performed using either acid digestionreduced aeration atomic absorption spectrophotometer or thermal decomposition atomic
absorption spectrometer. This section explains the former methodology.
‘9’ This operation flow involves the acid digestion-reduction aeration cold vapour atomic absorption
spectrometry, CVAAS, analysis method. Firstly, a sample is digested with nitric acid, perchloric acid,and sulphuric acid in an open vessel. After digestion, mercury in the sample solution exists in adivalent oxidized form, which is highly soluble in water. Once mercury is reduced with tin chloride toelemental mercury, which has low water solubility, it is vaporized and introduced into the CVAAS
instrument for measurement.
‘10’ Firstly, the collection of analytical samples is explained. Before measuring the actual sample,
the working condition of the analytical balance is confirmed. Specifically, weights or otherreferences are measured before using the balance every day to ensure that the correct value isdisplayed. Then, shredded hair is mixed thoroughly in a container, and approximately 10 mg of thesample is placed in the acid digestion vessel using tweezers or a spatula. In this video, a 50 mL
volumetric flask is used for digestion, as the shape is suitable for recirculating the digestion liquid.
The collected hair often adheres to the wall of the digestion vessel by static electricity. Hair adheredon the upper side of the digestion vessel is not digested sufficiently during the operation, so it should
be ensured that the sample is settled at the bottom of the vessel. The use of static remover isbeneficial.
‘11’ For blood and urine samples, approximately 0.5 g or two mL of sample is collected using apipette. Attention should be paid to the formation of clots in blood or precipitates in urine, which
compromise the homogeneity of the sample. The sample for analysis should be mixed well andused in a homogeneous condition.
‘12’ When collecting samples, standard solutions for calculating the sample concentrations are also
prepared. Amounts of mercury corresponding to those required to create the calibration curve aretaken from the standard stock solution with a syringe and placed in digestion vessels. An operation
blank without any additions, that is, neither standards nor samples, is also prepared. The preparedstandards are digested as done for the collected samples and analysed using CVAAS.

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‘13’ To confirm the reproducibility of the analysis, that is, the difference in results for analysing thesame samples, duplicate analysis should be performed at a certain frequency. Analysing the same
sample twice or more is recommended approximately once in every 10 samples. The reproducibilityof the analysis within a day can be evaluated by duplicate analysis. It is also effective to compare
the results between different days. For this purpose, it is recommended that a reference material of
the same type is analysed to confirm the variation for such reference materials on a regular basis.
Certified reference materials with traceable certified values given by national or international
standards are commercially available for human bio-samples. By analysing these certified referencematerials in the laboratory, the accuracy of the analysis can be evaluated.
‘14’ After preparing the samples, they are digested with acid. A piece of zeolite boiling stone isplaced in each sample and then one mL of deionized water, a one-to-one mixture of nitric acid andperchloric acid, and sulphuric acid are added. Then, the sample is heated and digested at
approximately 200 to 230 °C. Deionized water should not be added to urine samples. After digestingfor 30 minutes, the heating is stopped and the samples are left to cool to room temperature. Then,the volume of each sample is adjusted to 50mL. As soon as the digestion is conducted, theoperation details should be recorded. The necessary information for this pre-treatment operation
includes date and time, operator, sample amount, duration of digestion, and final preparation volume.
‘15’ After acid digestion, the sample is analysed using reduction aeration CVAAS. Firstly, the sample
is placed in the reaction vessel and the lid is closed. Then, tin chloride solution is added to the vessel.
Mercury in the sample solution in the instrument is reduced by tin chloride, vapourised, andintroduced into the detector. These operations may differ in different instruments, many of which
operate automatically, so reference should be made to the instruction manual of the instrument
being used. The analysis is performed in the order of operation blank, standard solutions for thecalibration curve, and then the samples to be analysed. If the number of samples exceeds 10, it isrecommended that a standard solution from the middle of the calibration curve is analysed every
10 samples to confirm that the sensitivity of the instrument has not drifted. Human exposure tomercury differs substantially depending on the living environment and diet, and even a person living
in a non-contaminated environment may sometimes have mercury levels beyond the range of thecalibration curve. In this case, the sample should be diluted and analysed again to ensure that theconcentration falls within the range of the calibration curve. After analysis of the samples, acalibration curve is prepared using the analytical results for the standard solutions to calculate theconcentrations of the samples.
‘16’ This slide explains the external factors that may affect the mercury levels in hair both positively
and negatively. Hair is a very good indicator for surveying people subject to methylmercury exposure.

113

In some cases, however, mercury may adhere to the outside of the hair. This may occur when aperson is exposed to air containing high concentrations of mercury at gold mining sites or in
mercury-using facilities. This may also be the case if a person is using a personal care product that
contains mercury as an active ingredient. These cases may result in a high level of elemental or
inorganic mercury adhered to the hair surface. Since mercury adhered to the surface is not causedby the digestion of methylmercury, it should not be assessed to evaluate the actual exposure andthe risk of methylmercury. Therefore, special care must be taken when assessing hair samples withhigh mercury concentrations on the external surface. On the other hand, hair bleaching andpermanent treatments can remove some of the methylmercury in hair. Therefore, the same careshould be taken when assessing the actual methylmercury exposure. Such supplementary
information can be obtained from the person subject to the survey using a questionnaire, which will
provide useful information.
‘17’ The importance of infection prevention during the handling of human bio-samples is explainedin this slide. Human samples such as blood may be contaminated with infectious bacteria, viruses,
etc. Therefore, great care must be taken to avoid direct contact with the sample. Gloves must be
used at all times when handling human specimens. The tools or devices use for analysing biologicalsamples may cause infectious diseases if they are left unattended after use. The pipette tips andempty containers used for collecting blood samples should be disposed of as infectious waste. The
glassware used for blood analysis should be soaked in a sodium hypochlorite solution for a while
and then washed.

114

5.7 Lecture 6: Methylmercury analysis‘0’ This lecture explains the analysis of methylmercury. There are several methods for analysing
methylmercury. The method found in the Mercury Analysis Manual in Japan is described here.

Section 1: Key features of methylmercury surveys‘1’ This section explains the key features of methylmercury survey.
‘2’ The biological effects of methylmercury are briefly addressed in this slide. Compared to inorganic
mercury, methylmercury has a longer half-life in living organisms, which makes it highly bioaccumulative. Methylmercury is known for its strong toxicity to the central nervous system.
Therefore, methylmercury in the environment is accumulated in the ecosystem and exhibits highloading levels and toxicity in humans and other organisms particularly in high trophic levels. For thisreason, analysing methylmercury is sometime more relevant than analysing total mercury.
‘3’ This slide highlights key features for the research and analysis of methylmercury in biota. The
toxicity and bioaccumulation ability of methylmercury is significantly higher than those of otherforms of mercury. The proportion of organic and inorganic mercury accumulated in the bodies ofliving organisms varies among species and individuals. Some species and individuals have arelatively low proportion of organic mercury in the body. Thus, assessing the methylmercury
concentration in the target species is an effective means of understanding the behaviour of mercury
in the ecosystem. Assessing methylmercury levels in food items is also relevant for evaluating theeffect on humans accurately. The Codex Guidelines, which define food safety standards, setguideline values for methylmercury in some fish species.
‘4’ When surveying human hair, it is sometimes important to know the level of methylmercury. As
hair only accumulates methylmercury in the body, all mercury in the hair should be methylmercury;
however, some elemental or inorganic mercury may adhere to the hair surface if the hair is exposed
to high concentrations. For example, atmospheric mercury at gold mining sites or mercury-using
facilities and personal care products containing mercury are possible sources of such mercury.
Mercury adhering to the surface is not accumulated by means of internal exposure tomethylmercury; thus, analysing total mercury including this surface portion will provide misleading
evaluation results. To assess the mercury exposure of the person subject to the survey property,
methylmercury in the hair samples should be analysed if the adsorption of elemental or inorganic
mercury is expected.

115Section 2: Methylmercury analysis‘5’ The actual analysis procedure for methylmercury is explained using fish as an example. The
process employs alkaline digestion, dithizone extraction and finally analysis by gas chromatography,
GC, with an electron capture detector, ECD.
‘6’ This slide shows the entire process of alkaline digestion, dithizone-toluene extraction, and
GC/ECD analysis. The principle of this method is to digest the sample with an alkaline solution, andthen to extract methylmercury into toluene as a dithizone complex. Organic substances other thanmethylmercury, which are also extracted in this method, will interfere with the analysis. The trick ofthis method is to remove most of the other organic substances coexisting in the sample by repeatedextraction and back extraction at different pH values to refine methylmercury. The operation flow
involves many steps, but this pre-treatment is normally completed in one to two days. The analysis
is then performed using a GC/ECD instrument, which is cheaper than a mass spectrometer and has
high sensitivity for specific substances such as methylmercury.
‘7’ The actual operations are described in videos. There are many steps in this analytical process,but similar operations are involved, which will be explained together. Firstly, a sample is weighed,and a solution of potassium hydroxide in ethanol is added. Then, the sample vessel is capped anddigestion proceeds in an oil bath heated for one hour at 100 °C. As alkali decomposes proteins very
well, almost no solids remain after digestion. Deliberate care should be taken in handling the alkaline
ethanol solution at high temperatures, which can cause severe burns.
‘8’ After alkaline digestion of the sample, the pH is adjusted to the acidic range to extract
methylmercury into the aqueous phase and separate it from coexisting lipids. Hydrochloric acid andhexane are added to the sample, which is then shaken and centrifuged to separate the hexane andaqueous phases. Then, the upper hexane phase is removed.
‘9’ After removing lipids by cleaning with hexane, the sample is extracted with a dithizone complex.
An EDTA solution and a precise amount of dithizone-toluene solution are added to movemethylmercury back into the toluene phase. After shaking, the sample is centrifuged to separate thephases completely, and the lower aqueous phase is removed.
‘10’ After extracting the methylmercury in the sample into toluene phase, the following steps are
performed: cleaning with alkaline aqueous solution, back extracting with sodium sulphide, cleaning
with toluene, acidifying and re-extracting, cleaning with alkaline aqueous solution, acidifying, andtransferring to a measuring vial. These steps remove co-existing matrices by back-extracting into
the aqueous phase and re-extracting into toluene. These individual operations are similar to the116previous steps. Finally, the sample is prepared in a small amount of toluene and analysed by
GC/ECD.
‘11’ The sample digested by alkali and refined by extraction is analysed by GC/ECD. GC/ECD
instruments are cheaper than mass spectrometers and have lower maintenance costs. In thismethod, a packed column is used for separating large amounts of sample to lower the detection
limit.

Section 3: Methylmercury analysis for human hair samples‘12’ In this section, the analysis of methylmercury in hair is explained.
‘13’ To analyse methylmercury in biological samples such as fish, a long pre-treatment involving
digestion and extraction is required to remove interfering components before the sample is analysed
by GC/ECD. For hair samples, methylmercury can be efficiently extracted by hydrochloric acidwithout digestion. Therefore, the analysis of methylmercury in hair can be conducted with a very
simple operation procedure as shown in the flow.
‘14’ This slide explains the actual analytical process for analysing methylmercury in hair. Firstly,
approximately 10 mg of hair is collected, and one or two drops of ethanol is added. Then, three mLof two-normality hydrochloric acid is added, and methylmercury is extracted into hydrochloric acidby heating for five minutes at 100 °C. After extraction, one mL of hydrochloric acid solution is takenfrom the sample, and toluene is added to transfer the methylmercury into the toluene phase. The
toluene solution of extracted methylmercury is analysed by GC/ECD in the same way as othersamples. Clearly, very few steps and a short time are required for hair analysis.

1175.8 Lecture 7 Mercury monitoring and theMinamata Convention‘0’ This lecture explains the legally-binding provisions of the Minamata Convention on Mercury
particularly the Articles that are relevant to mercury monitoring in multiple media.

Section 1: Outlines of the Minamata Convention‘1’ This section explains the backgrounds and scope of the Minamata Convention on Mercury.
‘2’ The Minamata Convention on Mercury is a multilateral legally-binding environmental agreement
aiming to protect the human health and the environment from anthropogenic emissions andreleases of mercury and mercury compounds. The text was adopted in October 2013 and iscomposed of a preambular text, 35 articles, and 5 annexes. The Convention entered into force on
16 August 2017, on the 90th day after the deposition of the 50th instrument of ratifications,
acceptance, approval, or accession.
‘3’ In its preamble, the Convention recognises the substantial lessons of Minamata disease, inparticular the serious health effects resulting from the mercury pollution, and makes aware of thehealth concerns to women, children, and future generations. The Convention sets out a range ofmeasures throughout the entire life cycle of mercury to meet its objective. Articles 3 to 12 relate tothe operational provisions describing the Parties’ obligations to reduce emissions and releases, with
controls throughout their life cycle, which include measures to control the supply and trade of
mercury, mercury-added products, manufacturing processes in which mercury or mercury
compounds are used, as well as artisanal and small-scale gold mining, ASGM. The text also includes
the articles on emissions and releases of mercury, environmentally sound interim storage, mercury
waste, and contaminated sites. Articles 13 to 21 facilitate the implementation of these measures
including provisions related to support for the Parties, information, awareness raising, and reporting.
Articles 22 to 35 cover the overall management of the Convention. Annexes A and B list the mercuryadded products and manufacturing processes to be controlled by the Convention. Annex C sets theitems to be included in the national action plans for ASGM. Annex D lists the point source categories
for emission control.
‘4’ The Convention covers all forms of mercury as element and mercury compounds. Specificmercury compounds are subject to control in Article 3, supply and trade, and Article 10, interim
storage. Article 4 specifies mercury-added products to be phased out or phased down by the Parties.

118Section 2: Measures to reduce mercury risks‘5’ This section explains the measures stipulated in the Convention to reduce mercury risks tohuman health and the environment.
‘6’ Article 4 Mercury-added products: Each Party shall not allow the manufacture, import or exportof mercury-added products listed in Part I of Annex A after the phase-out date, which is 2020 for the
products originally listed. Each Party also shall take measures to phase down the use of mercuryadded products listed in Part II of Annex A, which is dental amalgam. Each Party shall take measures
to prevent the incorporation of mercury-added products into assembled products and discourage
the manufacture and distribution of new mercury-added products. The Secretariat shall collect andmaintain information on mercury-added products and make it publicly available. The Conference of
the Parties, COP, shall review Annex A and may consider amendments. The first amendment was
adopted by the COP at its fourth meeting in 2022, which sets the phase-out for those newly listed in
2025.
‘7’ Article 5 Manufacturing processes in which mercury or mercury compounds are used: Each Party
shall not allow the use of mercury or mercury compounds in the manufacturing processes listed inPart I of Annex B, and shall take measures to restrict the use of mercury or mercury compounds inthe process listed in Part II of Annex B. Each Party shall also take measures to address emissions
and releases of mercury or mercury compounds from these facilities. Each Party shall not allow theuse of mercury or mercury compounds in new facilities and shall discourage their use of mercury
or mercury compounds in new processes. The Secretariat shall collect and maintain information on
processes using mercury or mercury compounds and make it publicly available. The COP shallreview Annex B and may consider amendments.
‘8’ Article 7 Artisanal and small-scale gold mining: Each Party with ASGM in its territory shall takesteps to reduce, and where feasible eliminate, the use, emissions and releases of mercury and its
compounds. Each Party with more than insignificant ASGM in its territory shall notify the Secretariat
and develop and implement a national action plan, which shall be submitted to the Secretariat within
three years after the development of the plan. Thereafter, a review of the progress made shall be
conducted every 3 years.
‘9’ Article 8 Emissions: A Party with relevant sources shall take measures to control emissions fromsources listed in Annex D. Each Party shall require the use of best available techniques, BAT, andbest environmental practices, BEP, to control emissions for new sources within five years after
becoming a Party and implement one or more measures for existing sources within 10 years after
becoming a Party. Each Party shall also establish and maintain an inventory of emissions. The COP
adopted the guidance on BAT/BEP, including goals and emission limit values for existing sources,

119the guidance on criteria to identify source categories, and methodology for preparing inventory. The
BAT/BEP guidance was adopted by the COP at its first meeting in 2017.
‘10’ Article 9 Releases: Each Party shall identify the relevant point source categories, which are notaddressed in the other provision of the Convention, no later than three years and on a regular basis
thereafter. Each Party shall take measures to control releases, and establish and maintain an
inventory of releases. The COP shall adopt guidance on BAT/BEP and methodology for preparing
inventories.
‘11’ Article 11 Mercury wastes: Mercury wastes means substances or object consisting of,containing or contaminated with mercury or mercury compounds in a quantity above the relevant
thresholds defined by the COP. Each Party shall take measures to manage mercury waste in anenvironmentally sound manner. Each Party shall also ensure that the recovery, recycling,
reclamation or direct re-use of mercury waste is for an allowed purpose or for environmentally sounddisposal only. For the Party to the Basel Convention, mercury waste shall not be transported acrossinternational boundaries except for the purpose of environmentally sound disposal. The COP shalldefine relevant thresholds for mercury wastes.
‘12’ Article 12 Contaminated sites: Each Party shall endeavour to develop appropriate strategies for
identifying and assessing sites contaminated by mercury or mercury compounds. Actions to reduce
the risks shall be performed in an environmentally sound manner. The COP adopted guidance onmanaging contaminated sites in its third meeting in 2019.

Section 3: Provisions facilitating the implementation of measures‘13’ This section explains the provisions of the Conventions that facilitate the Parties implementing
the measures to fulfil the objective of the Convention.
‘14’ Article 16 Health aspects: Parties are encouraged to promote the development andimplementation of strategies and programmes to identify and protect populations at risk. They arealso encouraged to promote the development and implementation of science-based educational
and preventive programmes on occupational exposure to mercury and mercury compounds, and topromote appropriate health-care services for prevention, treatment, and care for populations
affected by the exposure to mercury or mercury compounds. Furthermore, they are encouraged toestablish and strengthen the institutional and health professional capacities for the prevention,
diagnosis, treatment, and monitoring of health risks related to the exposure to mercury and mercury
compounds.

120‘15’ Article 18 Public information, awareness, and education: Each Party shall promote and facilitate
the provision to the public of available information, and education, training and public awareness
related to the effects of exposure to mercury and mercury compounds.
‘16’ Article 19 Research, development and monitoring: Parties shall endeavour to cooperate todevelop and improve inventories of use, consumption, and anthropogenic emissions and releasesof mercury. The cooperation also includes modelling and monitoring of mercury in vulnerable
populations and in environmental media, assessments of the impact of mercury on human healthand the environment, in addition to social, economic, and cultural impacts, information on theenvironmental cycle, transport, transformation and fate of mercury, information on commerce andtrade in mercury and mercury-added products, and information and research on the technical andeconomic availability of mercury-free products and processes and on BAT/BEP to reduce andmonitor emissions and releases of mercury. Additionally, Parties should build on existing monitoring
networks and research programmes.

Section 4: Overall management of the Convention‘17’ This section explains the provisions of the Conventions that provide overall management of theConvention particularly evaluating the effectiveness of measures to achieve the objective of theConvention.
‘18’ Article 22 Effectiveness evaluation: The COP shall evaluate the effectiveness of the Convention,
beginning no later than six years after entry into force and periodically thereafter. To facilitate theevaluation, the COP shall initiate the establishment of arrangements for providing itself withcomparable monitoring data on the presence and movement of mercury in the environment, andtrends in levels of mercury observed in biotic media and vulnerable populations.
‘19’ The evaluation shall be conducted on the basis of available scientific, environmental, technical,
financial and economic information including reports and other monitoring information, national
reports submitted, information and recommendations on compliance provided, and reports andother relevant information on the operation of the financial assistance, technology transfer andcapacity-building arrangements.

Section 5: Contribution of mercury monitoring to the Convention‘20’ This section describes the value of mercury monitoring for the effective implementation of the
Minamata Convention.

121‘21’ The Minamata Convention explicitly and implicitly refers to the monitoring required for its
effective implementation. Mercury monitoring facilitates the implementation of some measures.
The levels of mercury in environmental media or in products indicate the mercury risks to be reduced.
Geographical and temporal profiles of mercury levels are key data for evaluating the overall
effectiveness of the Convention.
‘22’ The mercury contents of products such as batteries, lamps, cosmetics, and pesticides can beused for import and export control as well as domestic market surveys. Skin whitening cosmetics
are still widely used by many women in the societies where lighter coloured skin is preferred. The
same information can also be used to estimate mercury stock in society and to forecast mercury
waste generation. Emissions and releases can be monitored to assess the environmental impactsof mercury source facilities. Contamination surveys of environmental media can provide importantdata for public information and awareness. Mercury monitoring is also essential for the soundmanagement of mercury waste.
‘23’ The human health concerns of mercury are twofold, namely health and safety in the workplaceand environmental health for vulnerable population such as pregnant women. As methylmercury,
inorganic mercury, and elemental mercury exhibit different toxicities in humans, mercury speciation
is important for proper risk assessments. From a scientific perspective, mercury monitoring isessential for research activities that provide improved knowledge about the fate and transport ofmercury as well as mathematical models for forecasting future trends. Additionally, the presence
and movement of mercury in the atmosphere as well as trends in biotic media and vulnerable
populations, such as children and women of child-bearing age, are useful for evaluating theeffectiveness of the Convention.

1225.9 Lecture 8: Quality management‘0’ This lecture explains the quality management of analytical data by referring to the definitions
provided by the International Organization for Standardization, ISO.

Section 1: Outlines of TQM, QA, and QC.
‘1’ This section outlines total quality management, TQM, quality assurance, QA, and quality control,
QC. QA and QC are often confused. These explanations also include some terminology.
‘2’ This slide shows the general principle of TQM. In fact, there is no clear definition of TQM provided
by ISO, or others. The general principle can typically be understood as an "all embracing discipline
to ensure the organization’s output".
‘3’ This slide shows the seven principles of quality management defined in ISO 9000. They are
customer focus, leadership, engagement of people, process approach, improvement, evidencebased decision making, and relationship management. These principles are described in ISO 9000,
but this idea applies universally across the management systems issued by ISO, including ISO/IEC
17025, where the system requirements are defined using the same philosophy.
‘4’ ‘Quality improvement’ is included in the configuration of TQM. It has often been questioned why
quality must be continuously improved, as quality beyond the current criteria would be excessive.
This criticism is refuted by the following explanation. Among industrial products with the same
performance specifications, products of good quality are sold at a high price. Analytical data is not
a commercial commodity per se, but high-quality data could create great value. For example, highly
accurate data can provide qualified information to the subject with fewer samples. Thus, improving
quality may offer new knowledge that was not previously understood.
‘5’ This slide explains the important points of a quality management system for an organization.
These are not the exact terms defined by ISO or others, but could be summarised by the sevenprinciples in the requirements of the ISO 9000 series and ISO/IEC 17025. They are clarified policy
and objectives of the system, documented protocol for the purpose, clear framework of the system,
properly obtained evidence, and appropriate resource management of human, material, budget, time,and information necessary for system operation. In a quality management system, it is importantthat these elements are clearly documented, properly implemented, and securely recorded.
‘6’ This slide indicates the necessary check items for quality management. Are the policy andobjective clear? Is the procedure appropriate? Are the rules and procedures fully documented? Are
the resources managed appropriately? Is the process conducted correctly? Is there sufficient123evidence? Is the quality of the products adequate? Are there sufficient check procedures andevidence? It is necessary to check these items and correct them, if they are insufficient, throughout
the system design and implementation. The first four are particularly important in system design,and the last two are important in system operation.
‘7’ It is important to keep in mind that quality management has its own purpose, which is not for thesake of obtaining ISO accreditation. The quality management process can be cumbersome as it
requires more steps. However, the quality management process clarifies the quality of laboratory
data, that is, accuracy, and makes it comparable with other data. Maintaining and continuously
improving the quality of data is the real value of quality management. It is emphasized that highquality data creates new value, such as discovering new knowledge; thus, the improvement in data
quality can be considered an improvement in the capacity of the laboratory.

Section 2: SOP and record: Process clarity‘8’ This section explains the items relevant to QC. There are two important components for processclarity: a standard operating procedure, SOP, and a record.
‘9’ ISO defines the term QA as the "part of quality management focused on providing confidence
that quality requirements will be fulfilled". QC is defined as the "part of quality management focusedon fulfilling quality requirements". Both QA and QC are considered part of overall quality
management.
‘10’Firstly, the meaning of the ‘quality’ in terms of analysis should be clarified. Since the obtained
data is the product of analytical activity, the quality of the analysis can be referred to as the qualityof data itself. How should the quality of data be measured? The quality of analytical data means thedegree of accuracy. Therefore, error in analytical data is the most important quality management
component. In general, errors are divided into bias from the true value and the uncertainty of theresult. The quality management of analysis is an activity to evaluate the magnitude of these errors
and to reduce such errors continuously.
‘11’ This slide explains how the quality of analytical data can be ensured. The quality of analytical
data should be ensured from two aspects: the adequacy of the process employed and the result
obtained. The adequacy of the process is ensured by a set of documents, including a clearly refined
SOP, evidence of correct operation that records that the operation was performed correctly
according to the SOP, and evidence of schedule control that ensures that the activities in the analysis
were appropriately done. The adequacy of the result is also ensured by a combination of several
types of information, including the results of QC test samples such as operation blanks, duplicate

124analysis, standards reference materials, evaluations of the experimentally obtained limit ofdetection, limit of quantification, and uncertainty, and the results of proficiency tests conducted
between laboratories.
‘12’ This slide explains the roles and effects of an SOP, which is an important document for
determining the analytical process. The key role of the SOP in quality management is to clarify theprocess of operation to avoid different operations being performed on different occasions or bydifferent operators. The documented SOP enables people outside of the system to objectively
confirm the operations being performed. The SOP in written form is an effective means of preventingchanges that may affect the results during the analytical operation, which tends to drift gradually
over time or with the replacement of operators. Other benefits of having an SOP include the easy
education and training of operation staff, and easy technology transfer to other laboratories.
‘13’ The key considerations for preparing an SOP are explained in this slide. Firstly, different frommanuals, SOPs are developed from the viewpoint of facilitating the actual operations in a laboratory.
The descriptions of the operations should be simple enough to be understood easily when
performing the operations. Additionally, the operational tips and warnings should be put on the same
page or close to it for easy reference instead of summarised on a separate page. On the other hand,
while keeping the descriptions as simple as possible, the SOP should include all factors that affectthe analytical data, such as the amount of sample to be used, the amounts of reagents, and thereaction temperature and duration. Without clear instructions on these elements, the quality of data
may vary on different operation dates or with different operators; therefore, these elements should
be addressed in the SOP. If some of the operation parameters in an SOP have been changed due toimprovements of the analysis method, such changes should be reflected in the SOP and theeffective date should be indicated.
‘14’ This slide shows a few more tips for developing an SOP. To make it simple and easy tounderstand, it is recommended that figures and photos are used effectively. When the contents of
the SOP are revised, the effective date will be very important when later checking the data. Thus,
whenever the SOP is revised, the effective date should be indicated, and the old version should be
removed promptly to prevent misuse. SOPs for sample management, such as sample naming, ID
assignment, classification, transportation, and storage, should be developed in addition to theanalytical operations to clarify the process of sample management. This is very important as
failures due to improper sample management frequently occur. Sometimes, preparatory tests may
have been carried out to determine some parameters, such as the amounts of reagents used in the
SOP. Attaching these test data to the SOP will be very useful when verifying analysis results or
improving the operations.

125‘15’ The record is another important factor for ensuring the analysis process. An SOP is developed
to clarify the operation of the analysis, but the actual analysis must be performed accordingly. A
record is essential evidence to prove that the analytical operations were performed according to the
SOP. Detailed records are not only very useful for proof of operation but also for proper datacollection. Analytical data may sometimes exhibit anomalies with values outside the normal data
range or different trends from past data series. In such cases, the detailed record from the time ofanalysis will help to determine whether the cause of the anomaly was an analytical error or a valid
reason due to the situation of the survey location or sample. In addition, the accumulation of past
analysis records can provide a reference of similar examples when analysing a special sample or areference for considering appropriate countermeasures based on the analysis situation of normal
samples.
‘16’ This slide explains the key considerations when deciding the contents of the record. In actual
analytical operations, many items, such as the amount of reagent to be added and, the heating time.,
rarely change and do not seem to differ in each analytical operation. Although it may seem
meaningless to record these items for each operation, it is actually useful to ensure correct
operations; thus, such information should be recorded each time, to the extent possible. It is
Important to note that the record is not the end product but is the information to be referred to at alater time. Therefore, a record form should be prepared for easier reference in the future. It is also
important to assign a unique ID to each analytical samples and enter it in the record to identify the
samples referred to in the record. The date and time of analysis, the operator, and the laboratory
room, if there are more than one, are some easily forgotten but important information for quality
management. The record form should be prepared to accommodate this information. During theanalytical operations, some abnormal situations may occur. A remark column in the record form canaccommodate such observations, which will benefit future analysis.

Section 3: QA/QC analysis of samples: Result validity‘17’ In this section, the use of operation blanks, duplicate analysis, and standard samples forevaluating the validity of analytical data are explained.
‘18’ The operation blank has great impact on the accuracy of analysis and the detection limit, so its
level must be minimised. Mostly, the operation blank level in chemical analysis comes fromcontamination of the air in the laboratory, elution from materials or residues of previous samples on
the glassware, accidental spillage of the target substances from other samples or standard
solutions during operation, or contamination of the initial reagents. For mercury analysis, the air inthe laboratory usually does not affect the blank, except in the case of ultra-trace analysis of samples

126

such as ocean water. Therefore, other factors, such as contamination of the apparatus or reagentsand contamination from other samples, need to be considered. The glassware must be thoroughly
cleaned after use so that no mercury from the sample remains. Soaking in acid, even in dilute
solutions, is an effective means of cleaning. Additionally, droplets of a sample solution are often
inadvertently dropped into other samples, blanks, or standard solutions. The analytical operation
should be carefully performed to avoid the mixing of such droplets, known as cross-contamination.
‘19’ Cross-contamination from the sample container or apparatus used for analysis can be avoided
by thorough careful cleaning. On the other hand, the effect of trace mercury in reagents is not easy
to eliminate. The best and simplest solution is to switch the reagent for mercury-free one. If this is
not possible, the analysis must be undertaken with a certain blank level. It is assumed that theamounts of reagents used for an analysis are usually the same for all samples and standard
solutions; thus, all the samples and standard solutions might be affected by the reagent to more orless the same degree. If the deviation of the operation blank is estimated in advance and proven tobe sufficiently smaller than the actual sample concentration, the effect of the blank can beeliminated by subtracting the value from the analysed concentrations of the samples and standard
solutions. The deviation of the operation blank is also related to the detection limit, which affects
the accuracy of analysis and the detection limit to a great extent. It may not be possible to obtaindata that meets the purpose of the survey if the blank value is larger than expected. It is particularly
important to estimate the level and deviation of the operation blank prior to the actual analysis toensure that the analytical operation meets the purpose of the survey.
‘20’ Duplicate analysis involves multiple analyses of the same samples. It is performed to check the
reproducibility of the analysis. The same samples are analysed more than twice with the sameprocedure and the differences are compared. To understand the general situation in the analysis,
the sample to be duplicated for analysis should be selected from among the samples with typical
properties. Additionally, a sample with a concentration that is sufficiently higher than the detection
limit should be selected to verify the differences among the analytical results. In some cases, theamount of sample is not sufficient for multiple analyses. Duplicate analysis may also be performed
with another sample with similar properties prepared for that purpose and analysed together withthe analytical samples.
‘21’ The reproducibility of the analysis within the same day can be assessed using the duplicate
analysis information, but the most effective way to confirm the reproducibility of the analysis
between different days is to analyse the same samples on every day of analysis. For this reason, it
is recommended that the same sample is analysed and the results are compared for eachprocessing batch for analysis, usually daily. Certified reference materials, CRMs, which have been127

evaluated jointly by many analytical institutions and given a certified value, are commerciallyavailable for use in the laboratory as a standard material. CRMs can be used to assess the
reproducibility of the analysis. Since the certified value is traceable to the national or international
standard, CRM analysis is a very useful method for understanding the level of bias in the analytical
data of the laboratory. CRMs are expensive materials for use in daily analysis, but it is recommended
that such as analysis is performed on a regular basis, if possible.
‘22’ As the name implies, CRMs are standard materials with certified values. The certified value isusually obtained through joint experiments by multiple analytical institutions, so that the traceabilityof the analysis is guaranteed and the uncertainty is estimated. The number after the plus-minus signin the certified value is sometimes misunderstood. The numerical value described as zero-point yy
is the uncertainty of the given certified value, that is, the degree of accuracy of the certified value. It
should be noted that this number is not the value obtained by the actual analysis of the CRM. Instead,the uncertainty of CRM is estimated from multiple analysis data, and not all analysis results fallwithin this range. Therefore, using this range to control the CRM analysis may disqualify laboratory
results that were actually completed properly. It should be noted that the criteria of the CRM analysis
should consider both the uncertainty of the certified value and the uncertainty of the analysis
conducted in the laboratory.
‘23’ The use of limit of detection, LOD, and limit of quantification, LOQ for QA/QC is explained here.
If the LOD of the analysis exceeds the concentrations of most of the samples, the survey may not
fulfil its purpose as these samples will be classified as “not detected”. To ensure that sufficient
analytical data is obtained to fulfil the purpose of the survey, the lowest value that is detectable in
the laboratory should be estimated prior to the analysis. The LOD and LOQ may change when theanalysis situation is changed due to the replacement or repair of analytical instruments, or otherreasons. In such cases, the values should be re-evaluated.
‘24’ The LOD and LOQ of the analysis need to be estimated from two perspectives. One is the limit
at which the measurement signal of the sample can be certainly detected, which is a judgment
based on the sensitivity of the instrument. The other is the reliability of the data obtained in theanalysis, which is a judgment based on the quantification of the results. For the sensitivity of the
instrument, the fluctuation of the baseline without a sample signal is considered noise; thus, thesignal of mercury must be sufficiently larger than the noise to detect the mercury in the sample. In
many cases, the signal is considered detectable when it is at least three times larger than the noise.
The results are considered quantifiable when the variation in the analytical results for a sample issufficiently smaller than the analytical value of the sample. This is determined by repeated analysisof the operation blank or the sample with the lowest possible concentration, ideally close to the128expected LOD. The analytical value that are sufficiently larger than these deviations are estimatedas the LOD and LOQ. Several methods have been proposed in various manuals and surveys tocalculate the LOD and LOQ from repeated analyses. One example proposes that the LOD isestimated as three times the standard deviation and the LOQ as 10 times the standard deviation for
repeated analyses. Another method calculates these values from the t value of the analysis results.
‘25’ A frequently asked question is, "How should the criteria be determined?". It is not possible todetermine absolute criteria for QA/QC sample data without considering the objective or
circumstances of the survey or analysis. The acceptable quality of data differs depending on theobjective of the survey or analysis. The QA/QC sample criteria must consider the objective of theanalysis normally performed in the laboratory. For example, the criteria for the operation blankshould be determined with the required LOD, and the criteria for duplicate analysis must consider
the acceptable uncertainty. The reference material criteria should also take into account theacceptable bias and the uncertainty of the laboratory analysis. The QA/QC criteria described inmanuals are determined based on the quality expected when the analysis operation is performed
properly.

Section 4: Quality of data: Bias and uncertainty‘26’ The most important factors for data quality are their errors, biases and uncertainties. Thissection outlines two of these factors: bias and uncertainty.
‘27’ Firstly, the text of Article 22 of the Minamata Convention on Mercury is shown here. The article
mentions the establishment of arrangements for providing itself with comparable monitoring dataon the presence and movement of mercury and mercury compounds in the environment as well as
trends in levels of mercury and mercury compounds observed in biotic media and vulnerable
populations. It refers to comparable data, but what does comparable data mean?
‘28’ By its nature, data is always compared with something. For example, it can be compared inchronological order with past or future data, compared with points that are spatially, geographically,
hydraulically, or meteorologically relevant, or compared with administrative standards or health risks.
In this sense, the data is retrieved for comparison. In many cases, the data is compared with dataobtained by many other institutions. This is especially significant when the purpose of the dataacquisition includes global environmental studies, such as the effectiveness evaluation of the
Minamata Convention. Therefore, data comparability is a very important concept.
‘29’ The importance of data comparability was emphasized but not defined in the Minamata
Convention. The important factors for data comparability are objectivity, reproducibility, and129

robustness. The following items are relevant for ensuring the comparability of data: the procedure
is obvious, the method has been verified, an external audit verification has been performed, and theuncertainty and bias have been verified.
‘30’ This slide illustrates data bias and uncertainty schematically. The centre of the circular target inthis figure indicates the true value, and the + marks indicate the obtained analysis data. The target
on the left has a small bias but a large uncertainty, that is, good accuracy but bad precision. The +marks are scattered around the centre of the target. On the other hand, the target on the right has alarge bias but a small uncertainty, that is, good precision but bad accuracy. The + marks areconcentrated in a small area away from the centre of the target. As efforts should be made to
improve both accuracy and precision in the analysis, properly evaluating the bias and uncertainty ofthe obtained data is a very important factor for understanding and comparing the data.
‘31’ The accuracy and precision can also be described statistically. The blue line in the figure
indicates the relationship between the data value and frequency. Bias is the difference between theanalysed average value and the true value, that is, the accuracy. As the true value cannot be obtained
analytically, an accurate bias value cannot be determined for the analytical data. If the analytical
data is obtained using a traceable system calibrated with national or international standards, thebias of the data can be evaluated against these standards, and the data can be precisely comparedwith other data evaluated in the same manner. Uncertainty is the degree of data variability when asample is analysed, that is, the precision. The uncertainty of an analysis can be estimatedexperimentally and analytically. The comparison of analysed data with other data becomes possible
through the evaluation of the bias and uncertainty of the analysis.

Section 5: Bias of data‘32’ This section describes traceability as a means of assessing data bias against standards.
‘33’ The term traceability is defined as the "property of a measurement result whereby the result canbe related to a reference through a documented unbroken chain of calibrations, each contributing
to the measurement uncertainty". Therefore, the fact that traceability is guaranteed means that thebias of data from the national or international standards is accurately estimated. For data securedby traceability in alignment with a standard, the bias against each other can be evaluated throughthe standard, even if the true value of the analysis cannot be known.
‘34’ A comparative test between laboratories or a proficiency test is also effective for evaluating thebias between laboratories. This test simply organizes multiple laboratories to analyse the same
parameter in the same sample and compares the results. Participating laboratories can see the130differences from other laboratories or standard laboratories, from which they can obtain information
about data bias between their own and other laboratories.

Section 6: Uncertainty‘35’ Another important factor, uncertainty, is explained in this section.
‘36’ The term uncertainty is defined as "non-negative parameters characterizing the dispersion of
the quantity values being attributed to a measurand based on the information used". Uncertainty isa value obtained by testing and calculation, which is referred to as "based on the information used".
‘37’ The process for estimating the uncertainty is explained here. Firstly, the analytical operations
are examined to extract possible factors affecting the data uncertainty for evaluation. A schematic
figure called a cause-and-effect diagram or fishbone chart is used for quality management. In thiscase, the diagram contains possible uncertainty factors involved in total mercury analysis with aciddigestion. The fishbone chart relates elements that are possible factors that may affect theuncertainty and puts them in their respective places. This chart helps in developing logicaldiscussions. It cannot directly estimate the uncertainty but serves as an effective tool to identify
relevant points for quality management including the uncertainty, and to discuss improvement
measures.
‘38’ Once the factors affecting the uncertainty of analysis are identified, the contribution of eachfactor to the uncertainty is estimated. In the “Guide to the expression of uncertainty inmeasurement”, GUM in short, two approaches for the evaluation of uncertainty are described. TypeA is a method deriving uncertainty from actual measured values statistically, and type B is a method
deriving uncertainty by other means than type A.
‘39’ The uncertainty assessment using the Type A approach is described here. The idea of Type A israther simple. The standard deviation is calculated from actual measurements conducted multiple
times. For example, the uncertainty in the amount of standard solution added is evaluated byactually collecting the standard solution multiple times with a pipette or syringe and measuring themass to calculate the standard deviation. The uncertainty of operation by Type A is the standard
deviation obtained from the measurements. It is not commonly practised in analytical operations
but if the average value of multiple operations is used, the uncertainty is the standard deviation
divided by the square root of the number of measurements.
‘40’ Type B applies to all information obtained by methods other than Type A. For example, acalibration report for an analytical instrument, the manufacturer’s specifications, the guaranteedvalue of the product, reference data taken from handbooks, or data from manuals and textbooks.

131Some of these data sources, such as calibration reports, describe the uncertainty itself, but in manycases, the uncertainty is not directly reported. In such cases, the uncertainty needs to be evaluated,for example, by assuming a probability distribution for the data.
‘41’ The uncertainty evaluated from the guaranteed value is used as an example of the Type B
approach. When assessing the volume uncertainty of a pipette or volumetric flask, which haveguaranteed volume values, uncertainty cannot be calculated because it is unclear how the actual
values are distributed. In this case, the uncertainty can be estimated by assuming a probability
distribution. If the data is assumed to be distributed to the normal distribution, the approximate
uncertainty can be obtained from a triangular distribution, as shown on the right side of the slide. If
the data is assumed to be distributed uniformly within the guaranteed value range, the uncertainty
can be calculated by assuming a rectangular distribution.
‘42’ Once the uncertainty of each element contributing to the uncertainty of the analysis is estimated,
they are combined to obtain an overall uncertainty. As shown in the formula, the squared values ofindividual uncertainty elements are used due to the propagation law of uncertainty and thensummed to estimate the overall uncertainty. There are many elements affecting uncertainty inanalytical operations as was shown in the fishbone chart. The magnitude of each element needs tobe considered, but it is not necessary to estimate and calculate the values for all of them. As shownin the formula, the individual uncertainty elements are squared, thus there is little contribution fromthe individual uncertainty elements that are less than one tenth of the maximum value. For thisreason, the elements that are sufficiently smaller than the maximum value do not need to be
included in the calculation. The uncertainty is calculated this way, but in many cases, the extended
uncertainty is obtained by multiplying the uncertainty by a factor to increase the range ofprobabilities that the uncertainty covers. As shown at the bottom of the slide, the expanded
uncertainty is calculated by multiplying the uncertainty by a coverage factor, to which a value of two
is usually assigned. The uncertainty is based on the standard deviation, so double the standard
deviation covers approximately 95% of the probability distribution.
‘43’ A frequently asked question is, “How much uncertainty is sufficient?” This depends on theobjective of the survey or experiment. Analyses are performed with various objectives, such asverifying the compliance of standard values, monitoring spatial or temporal trends, or evaluating thesignificance of differences between target groups. When evaluating the groups with small
difference, uncertainty of the analysis must be reduced. On the other hand, a relatively higher
uncertainty of analysis might be sufficient if there are larger differences between the subjects to beevaluated.

132‘44’ High-quality data has greater value and one of the factors affecting quality is uncertainty. When
judging the difference between target populations as being statistically significant, an analysis
operation with higher uncertainty may not be able to conclude that there is a difference, even though
the subjects might have verifiable differences. Additionally, when analytical data is used forparameters such as in environmental models, the uncertainty of analysis directly affects theprecision of the model.
‘45’ This slide provides an example of data uncertainty affecting the judgment of data reading. Boththe red and yellow plots are dispersed with the same variability around the lines. Although both
gradually decrease to the right, the trend in the red plot is obscured due to the uncertainty of thedata. The trend in the yellow plot is obvious despite the data uncertainty because the decreasing
trend is large enough.
‘46’ This slide provides an image of the significant differences between different case scenarios. As
shown in the figure on the left, a significant difference can be determined if the difference between
the targets is sufficiently large, even though the variation of the cases is large. If the difference
between the cases becomes smaller while the variation remains large, as is shown in the centre, it
may not be possible to conclude that the difference has significance. On the contrary, even if thedifference between the targets is small, it may be judged that the difference is significant if thevariation becomes sufficiently smaller. In real cases, the uncertainty of analysis does not always
affect significant differences, as target populations also have internal variation. Nevertheless,uncertainty must be managed appropriately as it may affect the interpretation of the data.

1335.10 Lecture 9: Laboratory safety andenvironmental management‘0’ This lecture explains safety and environmental management in the laboratory, which is notdirectly related to survey analysis. These items are basic but important for workers’ safety andreducing environmental impacts., so they should be well understood.

Section 1: Safe laboratory operation‘1’ This section describes basic precautions when handling hazardous reagents such as acids.
‘2’ Protective goggles should be worn if reagents may be scattered by heat digestion or otheroperations. When transferring samples or reagents, a safety pipette filler should always be usedinstead of sucking with the mouth. Operations generating hazardous fumes, such as acid digestion,
should be performed in a fume hood.
‘3’ Despite having safety measures put in place, accidents sometimes happen. If an acid or otherhazardous reagent adheres to the skin, it should be washed off immediately with plenty of water.
Even when wearing protective goggles, droplets of a reagent could possibly get into the eyes
through the gaps. An eye washing bottle is effective for washing reagents out of the eyes.

Section 2: Safe handling of hazardous reagents‘4’ This section identifies reagents that are highly hazardous and require safe handling, especiallythose that are often used in mercury analysis. These reagents have their own unique properties.
Understanding their properties is very important in laboratory safety management.
‘5’ Hydrochloric acid is a strong acid and vapour at room temperature. An aqueous solution ofhydrochloric acid is used as a reagent, which is prepared by dissolving hydrogen chloride in water.
Hydrochloric acid itself is a vapour, and due to this property, it gradually evaporates from its
concentrated solution. Therefore, a safety mask should be worn to avoid inhaling the vapour whenhandling this acid. Hydrochloric acid is classified as a strong acid, but it is weaker than sulphuric
acid. The mixing of hydrochloric acid with sulphuric acid results in the release of hydrochloric acidvapour into the atmosphere. Therefore, hydrochloric acid should never be mixed with a sulphuricacid solution. Hydrochloric acid is reduced in the presence of strong oxidants, and reduced chlorineions form chlorine gas; thus, mixing hydrochloric acid with an oxidant is extremely dangerous. For

134example, potassium permanganate, a strong oxidant used for mercury analysis, should never bemixed with a solution containing hydrochloric acid
‘6’ Sulphuric acid is explained in this slide. Many people believe that sulphuric acid is very dangerous;
however, this fear often arises from a poor understanding of its properties, which leads to it not
being handled correctly. Understanding the properties of sulphuric acid and handling it as shown on
this slide will lead to safe laboratory operation. Sulphuric acid is, of course, a very strong acid andcorrodes many metals. It is a non-volatile acid, meaning that it is not volatilized into the atmosphere,
unlike hydrochloric acid. Therefore, if dilute sulphuric acid solution adheres to skin or clothes, it
becomes more concentrated as water evaporates, which causes skin burns. Sulphuric acid also hasa very strong dehydration capacity. Concentrated sulphuric acid shows a strong digestive ability formany organic substances, as it affects hydrogen and oxygen in organic substances. A few otherimportant properties include a high heat of solution in water and the strong oxidizing capacity of hotconcentrated sulphuric acid. Another important note for handling sulphuric acid is that it oftencauses almost no pain to the skin in contract to hydrochloric acid or nitric acid. Thus, laboratory
workers can experience skin burns without having noticed that sulphuric acid was adhered to theirskin or clothes. If there is any possibility of contact with sulphuric acid, the affected part should be
washed with plenty of water. One should also be mindful to keep paper, cloth, metal, etc. away whenhandling sulphuric acid. As sulphuric acid has a high heat of solution, explosive boiling may occur
when adding water for dilution. When diluting sulphuric acid, it should be added into water little bylittle. If it is necessary to dissolve sulphuric acid in a small amount of water, for example, to prepare
20 normality solution, the process should be conducted under cooling conditions with ice water tolimit the increase in temperature.
‘7’ Nitric acid is explained in this slide. Different from hydrochloric acid and sulphuric acid, nitric acidis both a strong acid and an oxidant, with the oxidizing potential being maintained regardless of its
concentration. Due to this property, nitric acid corrodes many metals. When heated, it produces
nitric acid vapour and nitrogen oxide gas as a decomposition product, both of which are toxic tohumans. Additionally, it may be noted that nitrogen is a nutrient for plants and may lead theblooming of phytoplankton, although this is not relevant to the laboratory safety. Nitric acid should
be handled cautiously to avoid inhalation of and dermal contact with the toxic vapour generated
during heating operations. In addition, as nitric acid has an oxidizing capacity, it is dangerous,
particularly in the event of fire. Thus, nitric acid should be stored away from strongly reactive
substances, particularly metals, combustibles, and reducing agents.
‘8’ Perchloric acid is explained in this slide. Perchloric acid is a strong acid and has a very strongoxidizing potential, which makes it highly reactive and explosive on some occasions. However,135perchloric acid in aqueous solution is relatively stable and often used in acid decomposition. Thisis very useful for sample digestion due to the high reactivity of perchloric acid. Nevertheless, there
is a risk of explosion if handled incorrectly; thus, correct handling procedures should be put in place.
When conducting heat digestion with perchloric acid, nitric acid should always be used together
with perchloric acid. Additionally, the treated samples should never be dried, as perchloric acidbecomes unstable without water and can easily explode. Perchloric acid also generates a hazardous
gas containing hydrochloric acid during digestion operations. It should be handled cautiously to
avoid inhalation of and dermal contact with its toxic vapour.
‘9’ This slide explains the special precautions required for basic or alkaline solutions such as sodiumhydroxide. The hazardous properties of basic solutions seem to be less recognized than those ofacids. In fact, strong alkalis are very hazardous to humans. They have a strong ability to digest
proteins, which results in severe burns and can especially cause serious damage to the eyes.
Alcohol solutions of alkalis are more permeable to the skin, which risks more serious burns. Basicreagents such as sodium hydroxide have high heats of solution in water, which may cause a finealkaline mist to be emitted into the air when preparing an aqueous solution. As explained, strong
alkaline solutions are very harmful, similar to acids and other harmful reagents. Thus, the same levelof protective measures should be taken, such as wearing gloves and protective goggles whenhandling alkaline solutions. Mists of strong alkalis generated during operations should not be
inhaled.
‘10’ The handling of organic solvents is explained in this slide. The analysis of mercury does not very
often require the use of organic solvents but small amounts of organic solvent, such as toluene,
hexane, and ethanol, may be used for some analyses. These three solvents are volatile with relatively
low boiling points, which may cause an inhalation risk during handling. The flash points are also low,
and these solvents may ignite at room temperature. Needless to say, when handling organic
solvents, gloves and other protective gear should be used to minimize exposure. In addition,
sufficient ventilation should be provided in the handling area and operations should be performed
in a location free from fire.

Section 3: Apparatus and equipment safety‘11’ In this section, safety management for handling glassware and equipment is explained.
‘12’ Glassware is the most common cause of injury in chemical laboratories. Glassware in its proper
shape will not cause injures very often. Injuries are caused by fragments of broken or chipped136glassware. Broken glass is sharp and can sometimes pierce deeply. If the glassware breaks during
a forced operation, it can pierce even deeper into the skin.
‘13’ As glassware is used in laboratory, the edge is occasionally chipped. There are many injuriescaused by the edge of glassware. Such glassware should not be used or the chipped edge should
be repaired using a burner. Many injuries are also caused by picking up pieces of glassware that
was accidentally broken. A broom or other tools should be used for collection, or if picking by hand,
thick gloves should be used. As the appearance of glassware does not when heated, burns causedby hot glassware or injuries caused by dropping hot glassware are also common. Deliberate careshould be taken when handling apparatus that may still be hot after heat digestion.
‘14’ Sometimes, the lid sticks to glassware and cannot be removed. In such a case, forcibly removing
the lid may result in breakage and injury; therefore, the lid should not be twisted by force or withtools. It is also not recommended that glassware is heated to remove the lid, as this may damage
the glassware and cause serious injury. Boiling water or fire should never be used to remove the lidof glassware. If the lid cannot be removed, the area around the lid should be repeatedly tapped to
unscrew it gradually and patiently. It is also effective to use an ultrasonic bath.
‘15’ Fire is the most important concern when using electric appliances. Reagents such as acids usedin the laboratory can damage the electric wires, plugs, and outlets of electrical appliances, which
may cause a fire due to high temperatures or electric sparks. When using electric appliances, thecondition of the wires, plugs, and outlets should be examined, and damaged parts should be
repaired or replaced. It is safer to connect the plug of an electric appliance only when the apparatus
is in use and to disconnect it after use. If power outlets are located near the floor, the plugs or outlets
of electrical appliances may get wet. When using outlets located near the floor, water use in thelaboratory should be carefully controlled.

Section 4: Environmental management‘16’ In this section, environmental management in the laboratory including wastewater and exhaustgas management are explained.
‘17’ Even when a laboratory is working on environmental issues, it also impacts the environment
during operation. For example, laboratory activities constantly consume resources such as
reagents, electricity, water, and paper. Laboratory activities also result in the generation ofwastewater, exhaust gases, and solid waste. Although it may not be possible to eliminate theseissues completely, efforts to reduce the environmental impact must continue.

137

‘18’ Wastewater that is hazardous to the environment must be collected and treated properly andmust not be released directly into the environment. Besides wastewater containing hazardous
substances such as heavy metals, strongly acidic or alkaline wastewater must also be collected,
regardless of whether it contains hazardous substances. In some cases, acidic or alkaline
wastewater may be neutralized to remove its harm and then released if no other hazardous
substances remain in the wastewater. Usually, most laboratories outsource the treatment ofcollected wastewater. When outsourcing treatment, wastewater should be collected and kept
separately based on the type of substances it contains. To facilitate subsequent treatment, thedifferent types should not be mixed altogether. The type of wastewater and the contained
substances should be indicated on the container for safety and proper management during storage.
‘19’ Analytical operations that generate harmful gases, such as acid digestion, should be performed
in a fume hood. The air discharged from the hood contains acid gas or vapour, which must be
removed before release into the atmosphere to avoid environmental impact. Since the exhaustcannot be collected and stored, the acid in the exhaust from the fume hood should be removed bya gas scrubber. There are several types of gas scrubbers that can be installed indoors or outdoors.
The choice of a suitable scrubber depends on the laboratory situation. If a large amount of organic
solvents is used in a fume hood, which is not often the case with mercury analysis, the generatedorganic gas is not removed by standard gas scrubbers. When a fume hood is used for this purpose,an activated carbon filter or other device that removes organic gas is required.

Section 5: ISO 14001 environmental management standard‘20’ A standard for environmental management systems, ISO14000, is briefly introduced in thissection.
‘21’ The ISO 14000 series, including ISO 14001, is a standard for developing environmental
management systems. The difference from other quality standards such as ISO 9001 or ISO/IEC
17025 is that the ISO 14000 series covers all the activities of an organization to manage theenvironmental impact of the organization instead of focusing on specific activities. The
environmental impact of each activity of the organization are extracted and evaluated. A
documented environment management system based on the evaluated information is created. The
system is implemented, the outcome is confirmed, and the system and activities are continuously
improved. This flow is the same as the PDCA cycle in quality management systems. This meansthat the environmental management system is similar to the quality management system.

138‘22’ The benefits of introducing the ISO 14001 system have been explained in many places, including
by ISO itself. The benefits particular to the analytical laboratory are discussed and explained here.
Firstly, the environmental impact of the laboratory is systematically clarified and evaluated.
Laboratory activities are complex and use many chemicals, so some environmental impact might
be forgotten or neglected. Systematic environmental impact assessments help reduce suchoversights. Thus, the planning of environmental impact assessments facilitates easier
management. The operational advantage of the environmental management system in ISO 14000
is its similarity to the quality management system. As it belongs to the same family of ISO standards,
it is understandable to the analytical staff of the laboratory and relatively easy to introduce andimplement. Although it is not always necessary to obtain ISO 14001 certification, this series isnevertheless a very useful system regardless of having certification. Assessing the environmental
impact in alignment with ISO 14000 and managing the laboratory accordingly will reduce theenvironmental impact. Therefore, it is recommended that analytical laboratories incorporate thissystem into their management.

139

6 LIST OF ANNEXES
Annex A

Lecture 1: Physical and chemical properties, usage, and environmental behaviours(PowerPoint)

Annex B

Lecture 2: Atmospheric survey and analysis (manual active sampling method)(PowerPoint)

Annex C

Lecture 3: Solid sample (soil, sediment, and biota) survey and analysis (PowerPoint)

Annex D

Lecture 4: Water sample survey and analysis (PowerPoint)

Annex E

Lecture 5: Human biological sample analysis (PowerPoint)

Annex F

Lecture 6: Methylmercury analysis (PowerPoint)

Annex G

Lecture 7: Mercury monitoring and the Minamata Convention (PowerPoint)

Annex H

Lecture 8: Quality management (PowerPoint)

Annex I

Lecture 9: Laboratory safety and environmental management (PowerPoint)

140

UNEP
2022

UNEP (2022). Training package for mercury monitoring to enhance national
capacity to generate internationally comparable scientific data, Users’ manual,version 1.0. Bangkok: UNEP.

United Nations Environment Programme
Regional Office for Asia and the Pacific
The United Nations Building
Rajdamnern Nok Avenue, Dusit
Bangkok 10200, Thailand
Email: japanmercuryproject@un.org